final summer report kushal alacatel

A PROJECT REPORT ON

“Implementation of BSS Local Switching in Alcatel 5020 Spatial Atrium”

FOR

ALCATEL LUCENT INDIA LIMITED

UNDER THE GUIDANCE OF

MAHESH TRIVEDI ENGINEERING MANAGER

TOWARDS PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF

MASTER OF BUSINESS ADMINISTRATION (TELECOM MANAGEMENT)

SUBMITTED BY

KUSHAL GUPTA

Symbiosis Institute of Telecom Management Pune 411 016

2008-10

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PREFACE

Telecommunications industry is one of the fastest growing industries in the world. Two major factors responsible for the growth of telecommunications industry are use of modern technology and market competition. And with the advent of 3G technology, this growth seems to be unending. If we talk about Indian cellular industry in particular then as the year 2008 ended, India‘s mobile service providers boasts of nearly 347 million connections, a year-on-year increase of nearly 50 percent. In the first 2 months of 2009 alone, the mobile operators activated more than 28 million additional connections. However, the pace of this growth is now slowing down as saturation is coming in the market. In case of India, the urban markets are now on the verge of saturation as the teledensity in the urban sector has reached more than 86%. But the case is not same for Indian rural market where the teledensity is just about 15%. According to C. K. Prahalad, it‘s the Indian rural market which should now be the focus of the industry. Indian telecom industry is now eyeing the rural market for growth and expansion. The current technology however makes it unprofitable for the industry to expand in the faraway rural areas. This report deals with the new technology called ―BSS Local Switching‖ which can be implemented in Alcatel‘s Spatial Atrium. It deals how this new feature can be implemented in the already existing network. Thus with this new technology industry can now move on to the rural market for their growth and expansion. This would not only provide new means of revenue to the industry but the rural people can also now enjoy the benefits of this new technology.

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ACKNOWLEDGEMENT

The summer project at the Research & Development Centre of Alcatel-Lucent offered me both a learning experience, as well as, a glimpse into the daily management functions of an organization. During the tenure of this project, I was fortunate to have interacted with people, who in their own capacities have encouraged and guided me. I would like to express my gratitude to the management team at Symbiosis Institute of Telecom Management for giving me this chance. For their unstinted and invaluable guidance, I wish to express my heartfelt gratitude to my mentor Mr. Mahesh Trivedi, Engineering Manager, and my guide Mr. Ajay Mishra, Team Leader without whom this project could not have been realized. I would also like to express my sincere thanks to Mr. Ankur Kalra, Senior Engineer and Mr. Vijay Panchal, Engineer, for their expert guidance and constant cooperation. It was a privilege working with them and I sincerely thank them for advising us whenever the road map seemed blocked, despite of their busy schedule. I would also like to thank Mr. Senthil Kumar, Senior Engineer for giving me an opportunity to understand the laboratory functions at Alcatel. I would also take the opportunity to thanks all the members of the Integration Team who gave their constant support for the completion of the project and for sharing their insights and knowledge, derived from their years of experience in their particular areas of expertise. I would also like to express my deepest gratitude towards all those who have helped me in anyway. Finally, I would like to express my deepest gratitude towards the company, especially Mr. Chiradeep Roy (HR Dept.) and Mr. Vipin Kohli (Admin Dept.) for treating me in the most professional manner and catering to all my requirements.

Kushal Gupta

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OBJECTIVES

The title of this report is “Implementation of BSS Local Switching in Alcatel 5020 Spatial Atrium”. The report covers the following objectives: Understanding Alcatel 5020 Spatial Atrium and the services provided.

Understanding BSS Local Switching and its working.

Studying Software Development Life cycle at Alcatel Lucent

and finally, To implement the feature of BSS Local Switching in the

Spatial Atrium WSS. This report covers all about the network, its functioning, new needs and the development of new technologies to cater to these needs. It starts right from network architecture of Spatial Atrium to the implementation of a new feature i.e. BSS Local Switching in it. Thus the report is comprehensive in all aspects.

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COMPANY PROFILE

Alcatel-Lucent is a global telecommunications corporation, headquartered in Paris, France. It provides telecommunications solutions to service providers, enterprises and governments around the world, enabling these customers to deliver voice, data and video services. The company focuses on fixed, mobile, and converged broadband networking hardware, IP technologies, software, and services. It leverages the technical and scientific expertise of Bell Labs, one of the largest innovation and R&D houses in the communications industry. Alcatel-Lucent has operations in more than 130 countries. The company is under the leadership of Chief Executive Officer Ben Verwaayen and the non-executive Chairman of the Board is Philippe Camus. Alcatel-Lucent was formed when Alcatel merged with Lucent Technologies on December 1, 2006. However, the company as a whole has been a part of telecommunications industry since the late 19th century. The formation of Alcatel-Lucent created the world‘s first truly global communications solutions provider, with the most complete end-to-end portfolio of solutions and services in the industry. Alcatel-Lucent combined two entities — Alcatel and Lucent Technologies — which shared a common lineage dating back to 1986. That was the year Alcatel‘s parent company, CGE (la Compagnie Générale d‘Electricité), acquired ITT‘s European telecom business. Nearly 60 years earlier, ITT had purchased most of AT&T‘s manufacturing operations outside the United States. Lucent Technologies was spun off from AT&T. The Alcatel-Lucent Vision, Mission and Values form the cornerstones of company. These statements set the tone for the way the company operates. Vision - Definition of future success To enrich people‘s lives by transforming the way the world communicates. Mission - Purpose and path to realize the vision To use unique capabilities to ensure that customers thrive, businesses grow and enrich the personal communications experience for people around the world. Values - A system of shared beliefs that are at the heart of everything done - customer‘s first, innovation, teamwork, respect, accountability. With a strong focus on complete solutions maximizing value for customers, Alcatel-Lucent is organized around four business groups and three geographic regions. The Application Software Group focuses on developing and maintaining innovative software products for its global customer base. The Carrier Product Group serves fixed, wireless and convergent service providers with end-to-end communications solutions.

http://en.wikipedia.org/wiki/Ben_Verwaayen

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The Enterprise Product Group focuses on meeting the needs of business customers as well as the Industry & Public Sector. The Services Group designs, deploys, manages and maintains networks worldwide. The company's geographic regions are the Americas; Europe, Middle East, and Africa; and Asia Pacific and China. Alcatel-Lucent is one of the largest innovation powerhouses in the communications industry, representing an R&D investment of Euro 2.5 billion, and a portfolio of more than 26,000 active patents spanning virtually every technology area. At the core of this innovation is Alcatel-Lucent‘s Bell Labs, an innovation engine with researchers and scientists at the forefront of research into areas such as multimedia and convergent services and applications, new service delivery architectures and platforms, wireless and wireline, broadband access, packet and optical networking and transport, network security, enterprise networking and communication services and fundamental research in areas such as nanotechnology, algorithmic, and computer sciences. Market share highlights (2008)

#1 in Broadband Access with 40,6% of DSL market share (1) and 46.4% of GPON (1)

#1 in Optics (Terrestrial and Submarine) with 22.2% of market share (2) #1 in CDMA with 42.4% of market share (1) #1 in Western Europe Enterprise Telephony with 17% of market share #2 in IP/MPLS Service Edge Routers with 19% of market share (2) #3 in GSM/GPRS/EDGE Radio Access Networks with 10.8% of market

share (1) #3 in W-CDMA with 14.6% of market share (1)

Alcatel-Lucent Noida centre is a Research & Development centre where new software or their features are released as and when demanded by the customers. The centre employs a full-fledge laboratory for end-to-end testing.

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EXECUTIVE SUMMARY

Indian Telecommunications industry is at its pace now adding about 9 million customers per month. Earlier, the focus was on the urban customers but now the urban teledensity has reached almost 86% whereas the overall teledensity is 36%. So the focus has now shifted to rural areas where the teledensity is just 15%. But the companies are not fully ready to spread their reach in the rural areas, where on one hand the ARPU (Average Revenue per User) is quite low and on the other hand the technological restrictions do not allow them to expand in the faraway places. But as now the only way to maintain this pace is to expand so industry is now looking at the new technological innovations which would allow them to expand in the rural market in a cost effective way. This new technology is termed as the BSS Local Switching. In this technology, if the calling and the called parties are from same BSC/BTS then BSC will conduct the local switching for the services. As the BTSs can be quite far away from the BSCs, so Cell&Sat equipments are deployed which will send the voice and data from the virtual satellite link where the cost will be proportional to the traffic only and so the transmission cost be lowered for the operators which will enable the operator to provide the services in rural areas in cost effective ways. Now the operator already has the MSC employed in its place. As the new equipments are now installed and the switching needs to be done, so the MSC now needs to be configured in a way so as to be enable BSS Local Switching. So the next step is to configure the WSS (which actually acts as the MSC). The changes are to be made in the software of the hardware so the process followed is the Software Development Life Cycle. It has various phases viz. Feasibility study, Requirement analysis, Design, Coding & Unit testing, Implementation & System testing and Maintenance. The software is configured in a way which thus enables the BSS Local Switching in the Atrium WSS. This report thus deals with all the aspects of the Alcatel 5020 Spatial Atrium including the working of WSS and WMG. It deals with the necessities of the BSS Local Switching, what it is actually and how it will be embedded in the already present hardware. The report is thus comprehensive in all aspects and provides a detailed knowledge to the reader.

Kushal Gupta

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TABLE OF CONTENTS UNIT 1………………………………………………………………………………..10

Chapter 1 ................................................................................................................... 11 1.0 Introduction ..................................................................................................... 11

2.0 Today’s Architecture ....................................................................................... 12 3.0 DMSC Network Solution ................................................................................ 13 4.0 DMSC Technology Implementation in Existing Networks ............................ 15 5.0 Requirements of DMSC .................................................................................. 17 6.0 Introduction to Spatial Atrium ........................................................................ 18

7.0 Alcatel Spatial Atrium DMSC Features .......................................................... 20 8.0 Economic Advantages ..................................................................................... 22

Chapter 2 ................................................................................................................... 24 1.0 Introduction ..................................................................................................... 24 2.0 Atrium DMSC Nodes ...................................................................................... 24

3.0 Spatial Atrium System Architecture ................................................................ 25 4.0 Spatial Atrium Hardware System .................................................................... 28


2.0 Wireless Softswitch Hardware System ........................................................... 30 3.0 Capacity & Scalability ..................................................................................... 39

4.0 Netra Wireless Soft Switch System ................................................................. 42 Chapter 4 ................................................................................................................... 48

1.0 Introduction ..................................................................................................... 48

2.0 Wireless Media Gateway Hardware System ................................................... 48 3.0 WMG SuperSlots Design ................................................................................ 49

4.0 WMG Mid Plane ............................................................................................. 50

5.0 Control Module Card (CM) ............................................................................. 52

6.0 Service Matrix Card (SM) ............................................................................... 54 7.0 Packet Matrix Card .......................................................................................... 57

8.0 Voice Server Cards .......................................................................................... 57 9.0 Channelized Interface Card ............................................................................. 58 10.0 ATM Interfaces ............................................................................................. 61


2.0 Wireless Element System ................................................................................ 66

UNIT 2………………………………………………………………………………..70 Chapter 1 ................................................................................................................... 70

1.0 Introduction ..................................................................................................... 70

2.0 Bottom of the Pyramid (BoP) .......................................................................... 70 3.0 Indian Telecommunication Scenario ............................................................... 72

4.0 The limits of Traditional GSM ........................................................................ 74 5.0 About TTSL .................................................................................................... 75 TTSL to invest Rs 1K cr in rural expansion .......................................................... 76


2.0 Transmission costs .......................................................................................... 79 3.0 Traditional Solution ......................................................................................... 80 4.0 Broadband IP Satellite GSM Backhaul ........................................................... 80 5.0 Operational Scenarios ...................................................................................... 82

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6.0 Other Options: ................................................................................................. 84

7.0 Cost Savings by Creative Solutions ................................................................ 85 Chapter 3 ................................................................................................................... 88

1.0 Introduction ..................................................................................................... 88 2.0 Software Development Life Cycle (SDLC) .................................................... 88 3.0 Feasibility Study .............................................................................................. 88 4.0 Requirement Analysis and Specification ........................................................ 89 5.0 Design .............................................................................................................. 90

6.0 Coding and Unit Testing ................................................................................. 91 7.0 Integration and System Testing ....................................................................... 91 8.0 Maintenance .................................................................................................... 92

Chapter 4 ................................................................................................................... 95 Introduction ........................................................................................................... 95

Chapter 5 ................................................................................................................... 97

1.0 Introduction ..................................................................................................... 97

2.0 FEATURE DESCRIPTION ............................................................................ 98 3.0 System Level Design ..................................................................................... 102 4.0 Process Level Design .................................................................................... 104 5.0 UT TEST coverage ........................................................................................ 110

6.0 Deployment & Maintainability ..................................................................... 111 7.0 Future enhancements ..................................................................................... 112

Chapter 6 ................................................................................................................. 114

1.0 Introduction ................................................................................................... 114 2.0 Test Environment .......................................................................................... 115

3.0 Test Cases ...................................................................................................... 116

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Need of DMSC UNIT 1

Chapter 1

1.0 Introduction

The Problem: Although wireless telecommunications has been one of the true technology success stories of the past decade, the news hasn‘t been entirely good for wireless operators. While subscriber numbers are growing rapidly and wireless minutes are an ever increasing proportion of total telecommunications usage, revenues aren‘t growing as rapidly. Carriers are earning less revenue per user (ARPU), in large part due to price-based competition in which increasingly large buckets of minutes are offered for a flat monthly fee, so that users can make virtually unlimited calls without the carrier earning any additional revenue. Carriers are already starting to price data services in the same way, so there‘s little hope of increasing profitability through data offerings. At the same time, many carriers have curtailed capital expenditures in the past few years. As a result, carriers are now at a point where they have to add infrastructure in order to serve a growing number of customers, whether or not those customers are particularly lucrative. Operators are trying a variety of methods for cutting operating expenses, including network consolidation and operational centralization. What was once a patchwork of historically smaller operators has consolidated through mergers, acquisitions and partnerships to a smaller group of national and pan-national networks. These operators need to find a way to create a national-level nerve center for their mobile networks so they can offer national — or pan-national — service in a seamless way from a centralized operation. Other industry trends only add to the pressure. Mandates for Mobile Number Portability (MNP) will increase the number of non-revenue-generating calls as calls for subscribers who have changed providers will still have to go through their original home MSCs before being transferred to the new provider. Most operators face a complete overhaul of their entire network in order to evolve to 2.5 or 3G technologies. Any capital investments they make now must be made with this evolution in mind. Investing in legacy technology that has no future would be an expensive mistake. Operators also must consider how they plan to migrate to next-generation access technology. It will be a massive investment, so operators must make the evolution in an innovative way that can turn it into a competitive advantage.

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A Distributed Mobile Switching Center (DMSC) solution will help operators meet these challenges.

2.0 Today’s Architecture

An MSC originates and terminates wireless calls, with ongoing call control responsibility. It also performs mobility management functions, handling the complex process of correctly identifying the network location, appropriately allocating resources and directing traffic to and from subscribers as they move from cell to cell throughout the network. Today‘s mobile switching centers are based on wireline switches. Vendors added mobility functions to Class-5 switches to create mobile switching centers. This approach has numerous drawbacks for a mobile network. Traditional MSCs make it difficult and expensive to grow a mobile network. The traditional MSC is expensive to purchase and operate, requiring a dedicated technical support staff, so it often isn‘t economical to locate these switches close to subscribers, especially in more remote areas with lower subscriber densities. MSCs must be located centrally, with traffic backhauled over long-distance links from the remote locations. As a result, operating costs remain high because they must also factor in high backhaul costs. The traditional MSC is not a service-based environment, while mobile telephony is dependent on services. Customers are likely to make more use of a network when there are more services to use, and customers may even change providers in order to have access to the services they want. Installing new software to provision new services is cumbersome in the traditional switching environment, as each individual switch must be reconfigured any time there is any change in the network. Because MSCs are typically based on proprietary technology, vendors have to develop new services themselves rather than rely on third-party development. This makes service development and introduction a costly, time-consuming process. In this environment, it‘s difficult for carriers to keep up with market demand for new services, and that cuts into profits. The addition of data services to existing voice offerings makes the mobile network even more complex. To incorporate data offerings in a traditional architecture, new network nodes are needed because the existing voice nodes cannot handle data traffic. That means placing additional boxes at each point in the network, requiring more personnel, time, effort and expense to manage. Carriers must make these expenditures in order to offer any data services, even if subscribers aren‘t yet using these services enough to make the data equipment profitable.

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Solution: Alcatel 5020 Spatial Atrium supporting DMSC technology provides solution to the problems of today‘s network operators gearing for the future technologies.

3.0 DMSC Network Solution

The Distributed Mobile Switching Center (DMSC) is a departure from traditional telecommunications technology. It‘s based on an open platform, which offers numerous advantages over traditional switches. An open platform solution takes advantage of advances in the industry at large, from computing platforms to operating systems and protocol stacks. This architecture separates call control from the physical bearer path. Because the intelligence and complexity of this architecture reside in the call server, the media gateways that can be distributed throughout the network are less expensive and easier to maintain. The call server allows for centralized network management, which is ideal for the consolidated networks of today. Operators can concentrate their technical staff at the central network nerve center for better network control and better service transparency on a national level. This puts open platform developers ahead of the industry power curve because they can focus their development efforts on wireless service logic while relying on the best technology in the industry for other platform elements. In contrast, developers of proprietary legacy solutions must build everything themselves, from the ground up. As the industry moves toward an IP-based infrastructure, this becomes even more crucial, for it is difficult to keep up with advances in the huge libraries of IP stacks for protocols such as HTTP, SIP and PARLAY that have been developed for open platforms. In next-generation IP networks, services will be increasingly important, so it is crucial that there be IP-based APIs for developing these services. Distributed Mobile Switching Architecture is shown in the figure below:

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Central call server with distributed media gateways

Significant OPEX and CAPEX savings, Simplified operations, Long distance savings, IP-based services

Figure 1. Distributed Mobile Switching Architecture

Developers of distributed mobile switching solutions based on open platforms can achieve great economies of scale because they can leverage the development work already done for hardware and software by the computing industry at large, resulting in a lower per-port cost that lowers capital expenditures for operators. Open-platform development also allows a significant time-to-market advantage for the technology and for additional services. That means new services, features, functions and upgrades can be delivered more rapidly on an open platform than on a proprietary platform. The next-generation architecture of the DMSC also allows carriers to share network resources between data and voice services. The same network nodes can handle both data and voice traffic, simplifying the network and allowing carriers to more fully utilize network resources. The Traditional Circuit Switch MSC Network Configuration is shown below. As the traffic in the network increases then transport-related OPEX also increases. The next section describes how DMSC solution can be implemented in the existing network to reduce transport-related costs.

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Figure 2. Traditional Circuit Switch MSC network configuration

4.0 DMSC Technology Implementation in Existing Networks

One key application for the DMSC is switching within a region. In today‘s networks with traditional legacy switching technology, most operators don‘t deploy an MSC to a region until that region generates about 10,000 Erlangs of traffic —approximately 250,000 subscribers. Below this level, an MSC and the related operating costs and support staff needs are not cost-effective. There are, however, high ongoing operating costs associated with backhauling traffic from the region to a centralized MSC. Operators pay long-distance transport costs to and from the MSC, even for calls that are placed to numbers within that region. These costs add up, as up to 80 percent of all traffic is sent within the region. The majority of traffic, therefore, has to be sent unnecessarily across long-distance links. Only when traffic surpasses 10,000 Erlangs does it become reasonable to locate an MSC in a region, but even so there are high capital and operating costs involved. The switch itself is expensive, and there are associated real estate and power costs. An MSC requires a staff of at least six skilled engineers to keep it operational.

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Figure 3. Traditional MSC Network growth

In contrast, a media gateway connected to a centralized call server has been proven to be cost effective at 100 Erlangs of traffic — about 2,500 subscribers. The gateway itself is about a third of the cost of an MSC, has a smaller footprint and lower power and cooling requirements and, as a "dumb box" requires less technical support. This means an operator can begin switching calls regionally and saving significantly on transport costs far sooner than would be feasible with a legacy MSC. Operators building out a network and expanding into new regions can save themselves significant capital costs, as well as ongoing operational costs, by using the DMSC architecture in new service areas. The DMSC architecture helps keep growing networks from becoming more complex as they get larger. Adding a single call server and its subtending media gateways to the network is equivalent to adding just one additional switch to the network, no matter how many gateways controlled by the call server are ultimately deployed. For example, with 30 legacy switches and a new call server controlling 40 new media gateways, it is the same as managing a network with 31 switches. In addition to being used as an MSC substitute in new implementations, DMSC architecture can also be introduced gradually into networks as a supplement to legacy MSCs. Because it can convert TDM signals into packets, it allows operators who own their own packet backbone networks to bypass long-distance or inter-exchange networks. This is especially helpful when users are roaming and every call requires multiple long-distance trunks. As a network overlay, the distributed architecture also supports the introduction of IP-based services on an existing network. Transitioning to DMSC architecture allows carriers to cap their legacy investments so that all future capital purchases are prepared to support future

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needs, even as they‘re equipped to handle current network needs. W ith a distributed architecture in place, carriers are prepared for a seamless evolution to 3G access.

Figure 4. DMSC Network Solutions

5.0 Requirements of DMSC

Distributed network architecture introduces a new set of requirements for core network infrastructure. With a centralized control and distributed bearer arrangement, switching capacity requirements must expand to systems supporting millions of subscribers, with heightened reliability and quality of service (QoS) assurances. Specific requirements include:

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Massive system scalability – A central call server function demands a system that is scaleable to support subscribers on a network-wide basis, rather than just regionally. This may demand a system scaleable to many millions of users.

System reliability – Absolute reliability is a given with current switching

networks. The same is expected of distributed platforms and packetized networks. This becomes even more important as systems grow larger and single control functions are emphasized. Systems must be enhanced to protect operators from either system malfunction or building and/or natural disasters.

Footprint – A distributed architecture, with bearer path switching

elements placed in regional proximity to customers, is much more effective with dense hardware configurations. It is important that these overlay implementations do not require a significant amount of real estate or disrupt existing central office configurations.

Efficient switching for both TDM and IP – In most implementations, it will

be essential to have an efficient means to switch legacy TDM trunks alongside voice over IP (VoIP) or voice over ATM (VoATM) implementations.

Low cost – New systems must show significant capital cost

improvements that are commensurate with the introduction of new technology advances. Any additional CAPEX elements added to the network should be well offset by ongoing annual OPEX savings in resources, transport and facilities costs.

Enhanced services – There is a growing concern about the use of point

solutions for introducing new services. The proliferation of systems for different applications and services is quickly becoming unmanageable. Mobile operators are looking for single platforms in their network that can take on multiple personalities, with software upgrades. A DMSC is ideally situated in the network to perform a wide variety of innovative new voice and data service functions.

Evolution – One key benefit of a next-generation DMSC implementation

that is backward compatible to a 2G network is that the legacy investment can be capped and all new core network growth can be accomplished with investment in 3G network platforms. Any system introduced must be able to evolve to 2.5G, 3G or all-IP systems with only software upgrades.

These requirements have been fulfilled by Alcatel 5020 Spatial Atrium.

6.0 Introduction to Spatial Atrium

The Alcatel 5020 Spatial Atrium is a next-generation mobile switching product that bridges the voice and data signaling protocols of 2nd and 3rd generation

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mobile networks with intelligent networking. It provides packetized and channelized interfaces for interconnecting service provider‘s Mobile Switching Centers as well as interfaces that enable connection to external public telephone systems. Spatial Atrium may be used as Mobile Switching Center (MSC) with industry leading capacity utilizing the smallest footprint relative to today‘s networks. The platform is architected with very modular software and hardware enabling operator‘s to deploy only those elements needed for any particular application or network deployment. Spatial Atrium Distributed MSC is shown in the figure 5 below:

Figure 5. Spatial Atrium Distributed MSC

Spatial Atrium is capable of supporting

TDM Trunking (MF, ISUP), Multimedia Mobile Access, VoPacket Transport, Fully Integrated SS7.

As shown in the diagram above, it provides connectivity to the radio network and serves as the core network element for circuit domain services. On the backend, Spatial Atrium interfaces with today‘s network elements such as HLR, SMSC, and SCPs. Extensible in future to work with IP application servers such as VoXML, SIP and Parlay, the product fully supports an open Media Gateway Controller interface based on MEGACO, which allows for geographically distributing a call controller and the media gateways they control.

Distributed

Media

Gateways

Spatial

Atrium

WSS

WMG

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7.0 Alcatel Spatial Atrium DMSC Features

Superior density and scalability The Alcatel Spatial Atrium DMSC delivers a massively scaleable call processing system, supporting up to 500,000 subscribers per rack. Its system scalability from 50,000 to 5 million BHCA is unmatched in the industry. Each media gateway can simultaneously support more than 40,000 TDM DS0s and more than 20,000 ATM/IP ports. In addition, each call server can support up to 64 media gateways. Proven carrier grade reliability The Alcatel Spatial Atrium DMSC combines a carrier grade (99.99945% availability) redundant architecture with a platform proven through numerous commercial deployments. The call server is fully redundant with no single point of failure. A mated hot standby card backs each active processor card in the call server. Active and standby cards communicate over Ethernet and can be deployed in different geographic locations. Time to market The Alcatel Spatial Atrium DMSC is commercially available now. Geographic redundancy A high-speed wide-area Ethernet can be provided between two locations to support inter-processor communication. In such a deployment, the failure of one switch location will not jeopardize the call processing capability of the network, and any calls that have reached stable state will not be dropped. Any-any IP/ATM/FR/TDM switching (including native TDM-TDM) The Alcatel Spatial Atrium DMSC wireless media gateway has a unique architecture that supports packet (IP, ATM or frame relay) switching as well as native switching of TDM-TDM. A native TDM-TDM switching capability means network processing power doesn‘t have to be used to convert TDM to packet and back to TDM within the media gateway. Some solutions require GSM TDM signals to be converted back and forth between TDM and packet signals, but the Alcatel Spatial Atrium DMSC contains two separate switching fabrics, so TDM signals and services can remain within the TDM realm. Integrated Element Management System The Alcatel Spatial Atrium DMSC wireless Element Management (WEM) system offers fully integrated OAM&P of the call server and media gateway. Provisioning and monitoring of both elements can be managed from the WEM, eliminating potential inconsistencies and errors between call servers and media gateways. This significantly reduces the operational burden and eliminates unnecessary system management complexity. Flexible media gateway support and integration The Alcatel Spatial Atrium DMSC supports both H.248 (MEGAGO) and MCGP standards. Its integrated OA&M framework allows for the seamless integration of not only the Spatial Atrium media gateway, but also any media gateway that

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supports these open standards. This affords the greatest choice of performance, functionality and configuration flexibility for the operator. QoS Management QoS is critical to the success of these solutions and is a key consideration in all Alcatel Spatial Atrium DMSC design elements. Alcatel provides a pervasive framework that supports a comprehensive range of differentiated classes of service with different and manageable levels of QoS guarantees. Performance relating to codec and conformance, echo cancellation, delay, delay jitter or variation, and cell/packet loss is state-of-the-art. The result is a next-generation switch that maintains the same premium grade of voice quality that is the hallmark of the traditional TDM circuit switch, while also migrating voice services to packet-based networks. Multi-modal call model Alcatel Spatial Atrium DMSC integrates the voice, data and applications call/session management models and provides a central controlling function for all forms of voice and data communication (whether based on ISUP, IP, GTP/MIP or SIP), monitoring the sessions to allow seamless switching back and forth. The platform also provides a service creation environment and an API, and a set of predefined commands to simplify development of revenue-generating multi-modal ("mixed" voice and data) services. Alcatel‘s service solutions are also the first in the industry to support both voice calls and data sessions between non-IP 2/2.5/3G mobile and SIP (IP multimedia) capable appliances and work with SIP-based application servers, a unique multi-protocol capability. TDMA/GSM service transparency The Alcatel Spatial Atrium DMSC call server has a full CS-2 call model with CAMEL Phase II triggers. Coupled with the ANSI 41 signaling capability, it provides the operator with the ability to serve GSM overlays of TDMA networks and deliver GSM value added services (including prepaid) to TDMA subscribers. Multi-vendor interoperability The Alcatel Spatial Atrium platform has also undergone extensive multi-vendor interoperability tests, having been integrated into networks that use the HLRs, MSCs, GSNs, PDSNs, SMSCs, BSSs of most major switching, radio and applications infrastructure companies. Alcatel has also achieved SS7 integration with both ETSI and ITU ISUP based networks. Ready for the future As access networks and handsets evolve from 2G to 2.5G to 3G all-IP, Alcatel‘s Spatial Atrium solution requires only software upgrades on the same hardware platform to provide the network and service enhancements brought on by higher bandwidth and all-IP.

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8.0 Economic Advantages

So now we can summarize the advantages of Spatial Atrium over the Legacy Networks. If we particularly talk about the Economic Advantages of the DMSC solution then they are given below:

It allows a simplified network that requires less long-distance

backhaul. It requires fewer trained people to operate and has a smaller

footprint, with reduced power and cooling requirements. The equipment itself has a lower price per port than a legacy MSC,

offers IP and ATM interfaces on the media gateway so no additional hardware is required, and has IP service interfaces on the call server.

The open architecture allows rapid time-to-market for new services — in as little as three months time from concept to implementation

Other advantages which DMSC infrastructure offers are:

Operational & capital savings opportunities for wireless carriers, Operators building out network in new areas can reduce operational

& capital costs. DMSC architecture helps growing network from becoming complex

as they get larger, Adding a single call server and its subtending media gateway to the

network is equivalent to adding just one additional switch to the network e.g. with 30 legacy switches and a new call server controlling 40 media gateways, its same as managing a network with 31 switches,

DMSC architecture can be introduced gradually into network as a supplement to legacy MSCs,

It converts TDM signals into packets so the operators who own their own packet backbone network can now bypass long-distance or inter-exchange network. This is helpful in nationwide roaming where every call requires multiple long distance trunks,

It also supports introduction of IP-based services on an existing network.

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Alcatel 5020 Spatial Atrium UNIT 1

Chapter 2

1.0 Introduction

In the 1st chapter, an overview of the problem faced by telecom operators and its solution by the way of DMSC technology has been provided. In this chapter, the hardware of Spatial Atrium is provided to give an idea about how it actually functions.

2.0 Atrium DMSC Nodes

The Spatial Atrium comprises of three major building block elements:

The Wireless Softswitch (WSS) – the Softswitch,

The Wireless Media Gateway (WMG) – the Media Gateway and,

The Wireless Element Manager (WEM) – the Element Management

System

Figure 6. Spatial Atrium

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Alcatel simplified architecture encompasses all the functions required in a DMSC on three platform elements:

1. Wireless Softswitch (WSS) – The Wireless Softswitch (WSS) call server incorporates the media gateway controller, signaling gateway, element management, and call server into a single powerful integrated computing platform built on industry-standard computing elements. It is designed in line with 3GPP Release 4 standards. It supports GSM/UMTS network signaling interfaces (A, RANAP and MAP) legacy PSTN signaling interfaces (SS7 ISUP and MF), and EGCP interface (a binary variant of the emerging H.248/Megaco standard) for communicating with subtending media gateways.

2. Wireless Media Gateway (WMG) – The Wireless Media Gateway (WMG) is a high density, multi-service media gateway with voice and data bearer interfaces (TDM, IP, ATM, and RTP/RTCP). It is capable of performing any-to-any switching with a unique architecture that not only supports TDM-Packet switching, but also native TDM-TDM (with high quality, high capacity and capital efficiency). The WMG includes centralized media server resources (for conference bridging, tones, announcements, DTMF and Legal Intercept) so no external media servers are required. It communicates with the WSS using the EGCP interface.

3. Wireless Element Management System (WEM) – The Wireless Element Management (WEM) offers fully integrated OAM&P and an FCAPS GUI for both the WSS and WMG. Provisioning and monitoring of both elements can be managed from the WEM, thus eliminating potential inconsistencies and errors. It communicates with the call server and media gateways‘ using SNMP v2 interface and offers SNMP v2 and Command Line (CLI) interfaces for communicating with external NMS/OSSs. Open SNMP and CLI (via CORBA 2.3) interfaces permit carriers to exchange Atrium OAM&P information with other network operations systems. This support of open northbound interface protocols ensures maximum flexibility when integrating the Spatial Atrium system.

Spatial Atrium‘s Wireless Softswitch (WSS) is built upon commercially available hardware platform to provide a highly reliable carrier grade architecture. Spatial Atrium is a fully redundant system. A protected card backs every active processing card in an Atrium. The active and standby cards communicate via Ethernet over a highly reliable managed service network, thus enabling the geographical separation of active and standby processing elements.

3.0 Spatial Atrium System Architecture

The Spatial Atrium offers a unique architecture intended to facilitate the migration of circuit-domain services from the traditional legacy solution to a flexible architecture based on packet protocols and open standards.

26

The Wireless Softswitch (WSS) interworks the circuit-based, narrowband call signaling protocols with the signaling protocols of the packet network and vice versa. The Wireless Media Gateway (WMG) is the underlying voice and packet switching element in the Spatial Atrium. Spatial Atrium functionalities include:

Wireless Softswitch: o MSC/VLR: location updates, call handovers, mobile call handling,

carrier selection, Short message handling, Supplementary Services, Call Independent Supplementary Services (CISS) handling, etc.

o Gateway MSC: HLR query for call delivery, carrier selection, etc o Signaling Directory Routing: E.164, E.212, NANP, etc o Signaling Gateway: SS7 SSP such as Multiple Point Code,

PC+SSN and GTT routing, etc o Network Services: Supplementary services, IN services, Prepaid

services, Mobile Number Portability services, etc

Integrated WEM server for FCAPS capability of Alcatel WSS and Media Gateways: o Fault o Configuration o (Accounting) Billing capture o Performance o Security

Media Gateway: o Connectivity via: TDM, IP, ATM AAL2 SVC including any-to-any

combinations o TDM Bearer Interfaces: T1, E1, DS-3, OC-3 and STM-1 o ATM Bearer Interfaces: DS-1, DS-3, OC-3c, STM-1c, OC-12c,

and STM-4c

System Performance: o 64 Media Gateways per WSS

The figure showing Spatial Atrium System Architecture is shown below:

27

Figure 7. Spatial Atrium System Architecture

The WSS part of Spatial Atrium comprises of the following functional components: Signaling Interface Module (SIM), Data Distribution Module (DDM), System Administration Module (SAM) and Call Control Module (CCM). The functions of each module are outlined in subsequent subsections. Spatial Atrium Wireless Soft Switch is made up of a group of processors that have been architected to be highly scalable and distribute the various functional loads on an MSC. All SS7 signaling, including MAP, CAP, ISUP, BSSAP and RANAP enter the system through a Signaling Interface Module (SIM). The SIM cards are n+1 redundant for scalability and high availability. The SIMs receive messages from MSCs, HLRs, SCPs, SMSCs, BSCs, RNCs, STPs, WSSs and other SS7 network elements, such as International Gateways or PSTN end office switches. The SIM process the MTP1, MTP2, MTP3, SAAL, MTP3b and SCCP portions of all SS7 messages. The SIM card is responsible for distributing the messages to the Data Distribution Modules (DDM). The Data Distribution Module (DDM) is responsible for load balancing messages to the appropriate Call Control Module (CCM). When a mobile subscriber initially registers on the MSC, it will be assigned to a particular CCM by the DDM, after which all messages associated with that subscriber will continue to be routed to the CCM responsible for handling that subscriber. The CCMs contain all the VLR entries, and are responsible for mobility management, call/connection and feature processing. The System Administration Module (SAM) provides the facility management, managing status (availability) of the various media connections available within the media gateway, in addition to overall Operations, Administration, Maintenance and Billing responsibility.

28

PDU

WSS

Chassis

84 inches

28.5 inches

34 inches

10.5 in.

Figure 8. Spatial Atrium Hardware System

4.0 Spatial Atrium Hardware System

The Spatial Atrium product is comprised of the following physical subsystems and components: Wireless Soft Switch (WSS) subsystem Wireless Media Gateway (WMG) subsystem Wireless Element Manager (WEM) subsystem Power Distribution Unit (PDU)

Each component viz. WSS, WMG, WEM etc. are explained in the further chapters of this report.

30

Wireless Soft Switch UNIT 1

Chapter 3

1.0 Introduction

A softswitch is a central device in a Telecommunication network which connects calls from one phone line to another, entirely by means of software running on a computer system. This work was formerly carried out by hardware, with physical switchboards to route the calls. A softswitch is typically used to control connections at the junction point between circuit and packet networks. A single device containing both the switching logic and the switching fabric can be used for this purpose; however, modern technology has led to a preference for decomposing this device into a Call Agent and a Media Gateway. Typically the larger access devices will be located in a building owned by the telecommunication company near to the customers they serve. Each end user can be connected to the IAD by a simple pair of copper wires. The medium sized devices and PBXs will typically be used in a business premises and the single line devices would probably be found in residential premises. In more recent times (i.e., the IP Multimedia Subsystem or IMS), the Softswitch element is represented by the Media Gateway Controller (MGC) element, and the term "Softswitch" is rarely used in the IMS context, but another word of AGCF(Access Gateway Control Function).

2.0 Wireless Softswitch Hardware System

As introduced in the previous section, the WSS platform hosts the Call Server, Media Gateway Controller, Signaling Gateway and Wireless Element Manager, all on a single platform. The WSS platform provides extreme flexibility and a high economic scalability in system deployment across the range of small, medium or large networks. In small installations, all of these applications may be hosted on a single WSS chassis. As network expands additional processing modules or WSS chassis can be added to accommodate the extra traffic load. The chassis can accommodate up to 12 boards. All boards in a WSS chassis plug into a backplane that distributes power to all modules. The physical components that comprise the WSS chassis are listed below, followed by the description of each of the component:

31

a) Processing modules to support various functionalities (SIM, DDM, CCM, AIM, and SAM) b) Power Supply Modules (PSM) c) Peripheral devices d) Ethernet Switch Module (ESM) Figure 10 shows the Wireless Soft Switch Hardware platform followed by the description of each individual component.

Figure 10. Wireless Soft Switch Hardware Platform

32

2.1 Signaling Interface Module (SIM)

Hardware Features

650 MHz Ultra Sparc IIe with on chip cache

1 GB RAM

Three Ethernet ports

Inter host IPMI System Management bus

Hot Swap capability

Daughter (SS7 Link) card

30 GB IDE Hard Disk

2 Serial, 2 USB ports Figure 11. SIM

Software Features

Solaris 5.8

Dynamic reconfiguration (CPU, Memory, Disks)

Different Scheduling Priorities including RT

Diskless boot support and NFS logging

All signaling physical links terminate on the SIM and each module terminates up to 2 DS1 or E1 links with individual links speeds of 56 kbps or 64 kbps. There are pre-defined sets of links attached to each SIM and is responsible for distributing signaling loads among DDMs. The SIM operates in a load-shared mode at the factor of N+1, it can send signaling information to any of the DDM modules within the switching complex. The signaling links (T1/E1) terminate on a SS7 daughter card that resides on the SIM card. The module powered by an Ultra SPARC-2E processor operating at 650MHz, and has 1GB RAM on board.

33

2.2 Data Distribution Module (DDM) Hardware Features


1 GB RAM


30 GB IDE Hard Disk


Hot Swap capability Figure 12. DDM

2 Serial, 2 USB ports Software Features

Solaris 5.8



Diskless boot support and NFS logging The DDM is responsible for distributing signaling messages among CCMs. Each DDM hosts a distribution process that implements unique message distribution logic. The purpose of the logic is to keep the particular call instance on one CCM process for the complete duration of the call for a specific subscriber. DDM knows which Call Processing card to send the signaling information based on in memory data structures mapping different signaling types to CCMs. The module has an Ultra SPARC-2E processor operating at 650MHz, the on board memory is 1GB expandable up to 2GB. All the DDMs in the WSS work in a load-shared fashion with N+1 redundancy.

34

2.3 Call Control Module (CCM) Hardware Features


1 GB RAM


30 GB IDE Hard Disk


Hot Swap capability Figure 13. CCM

2 Serial, 2 USB ports Software Features

Solaris 5.8




The CCM provides Call processing for voice and data, Mobility management, VLR functionality, signaling gateway, billing and OAM. Mobility management is for keeping the users mobile (updating location, handoffs from one cell to another, etc), the VLR is a database for information on subscribers currently using the system resources while the signaling gateways are protocol translators. These cards operate in a load-shared mode with N+N redundancy (active-standby) for applications requiring connection management/processing. The number of CCM cards in a chassis depends on the message processing capacity of each card. The module has an Ultra SPARC-2E processor operating at 650MHz, the on board memory is 1GB expandable up to 2GB.

35

2.4 System Admin Module (SAM)

Hardware Features

Four 450 MHz Ultra Sparc II UPA Modules

4 GB RAM

Quad Ethernet ports

Four High Performance SCSI Hard Disk

Six available PCI slots

Hot Swap capability Figure 14. SAM

Upbeat middleware component for failure detection and fail over control

Software Features

Solaris 5.8




The SAM performs OAM functionality of WEM, with billing, a persistence database to store the system configuration data and a repository for CDRs (Call Detail Records). The SAM is also responsible for interfacing to the external devices, such as, tape drive, disk drive, CD ROM. The box has four 450MHz Ultra SPARC- II UPA modules, with 4GB memory and operates in an active-standby mode.

36

2.5 Power Supply Module (PSM)

Hardware Features

500 Watt

Dual Feed

Alarm/Standby Power Fuse

Input –42VDC to –56VDC

Temperature -5 C to 50 C (Operating)

Humidity 5% to 90% Relative Humidity Figure 15. PSM

The PSMs distribute power to various modules within each chassis. At least 2 power supply modules are required for each fully loaded chassis. There are three PSMs in a chassis providing 2+1 redundancy. All 3 modules operate in load sharing fashion. Each of the PSM provides –48VDC at a rating of 500 W.

37

2.6 Ethernet Switch Module (ESM) 10Base- T/ 100Base- TX, and 1000Base- T ports in the following modes:

Hardware Features

10Base- T full- duplex mode

10Base- T half- duplex mode 100 Base- TX full- duplex mode

100Base- TX half- duplex mode

Auto- sensing mode

LEDs: Front panel, Power, Pull, Link, Activity & Swap

Hardware Features, Electrical:

16W of + 3.3Vdc maximum power consumption Mechanical

CompactPCI 6U, 1 slot (4HP)

- 5 º C to 50 º (Operating) Humidity Figure 16.

ESM

5% to 90% relative humidity, non-condensing

Spatial Atrium includes a redundant pair of 24- port Ethernet switches, each providing 10/ 100Base-T Local Area Network (LAN) connectivity for connection and communication between the components of the Spatial Atrium. ESM is also used for communication between WSS chassis.

38

Hardware Features

4 front, 4 rear

Fan capacity 102 CFM

Minimum Airflow Front 300 LFM

Minimum Airflow Rear 150 LFM

Dual input power feed

Status LED

Power feed LED

Alarm indicator

Hardware Features DDS- 2, DDS- DC, DDS type Read/ write compatibility

Sustained transfer rate (native) 33 Mbytes/ min

Sustained transfer rate (compressed) 66 Mbytes/ min

Max burst transfer rate (synchronous) 600 Mbytes/ min

Max burst transfer rate (asynchronous) 420 Mbytes/ min

Average access time (max capacity) 40 Seconds

Default buffer (cache) size 1,000 Kbytes

Hardware Features Up to 36GB

Telcordia NEBS GR- 63- CORE Level 3 compliance

Telcordia NEBS GR- 1089- CORE Level 3 compliance

One activity LED per bay

Ultra- Wide SCSI- 2 Bus; 40MB/ s Capable

Power (Per Disk) 20W Idle

Electromagnetic Compatibility (EMC) FCC Class A

Disk Drive Tape Drive

Rear view

Front view

Fan Tray

2.7 Peripheral Devices Peripheral devices are hard disks, CD ROM and and tape drive. There are two hard disks in the system for redundancy. The pair works in mirrored fashion loading the software in parallel for application and OS, thereby reducing the booting time. Each of the hard disk is 36GB. A tape drive attached to the system can be used for data storage.

Figure 17. Peripheral Devices

39

2.8 Alarm Indication Module (AIM) The AIM is responsible for indicating alams and faults generated by any of the modules within the WSS chassis. The subsystem uses green LEDs to indicate normal operation and amber LEDs to indicate fault conditions. 2.9 Mid Plane The mid-plane of the compact PCI chassis provides the power and ground to call cards in the chassis. It also provides Ethernet connectivity as well as connections to the rear transition modules.

3.0 Capacity & Scalability

The distributed architecture of the Alcatel product allows the system to support highly scalable call capacity. At capacity each component is loaded less than 80% of its full load. On the other hand a fully loaded WMG configured with DS3 can support up to 56k DS-0 ports. Alcatel product is engineered with varying number of WSS and WMG chassis depending on the application and traffic load. 3.1 WSS Scalability The following diagram illustrates the overall call processing architecture (patent pending) that allows the system to scale almost linearly. The SIM module provides SS7 interface to the other elements in the network. The ESM module provides IP connectivity to the Media Gateway for EGCP (H.248 call control), and the SAM module provides IP connectivity for FCAPS and Billing. The SIM module selects one DDM module to send the very first incoming message of a call or transaction. The DDM, which works as an internal router, routes the message to one CCM module and the related subsequent messages to the same CCM module. Figure 18 below shows the WSS Scalability and how it is done.

40

Figure 18. WSS Scalability

The current Atrium release supports up to 38 cards in a single system providing a capacity of roughly 400K BHCA. 3.2 SIM Module Scalability The SIM module has all the SS7 signing links terminating to it, each module is capable of supporting up to 48 DS0 channels (up to 2 T1s of physical links) or 64 DS0 channels (up to 2E1s of physical inks). Provisioning of the Alcatel system ensure balancing of load on the SIM modules in the system (load shared redundancy), thus additional SIM modules will dimension the system to handle more traffic , as shown in figure 19 below:

41

Redundant Communications Backbone

Communications Backbone

Data

Distribution

Module - NData

Distribution

Module

Additional card will scale

the system upwards

stanby card, but load

sharing, for the N+1 load

shared redundancy

Figure 19. SIM module distribution

3.3 DDM Module Scalability Each DDM hosts a distribution process that implements unique message distribution logic to process and distribute signaling messages to CCMs. Scalability is achieved by adding more DDMs to support the increase in capacity requirement, illustrated in Figure-20.

Figure 20. DDM module distribution

3.4 CCM Module Scalability The Call Control Module (CCM) has Call processing responsibility for both voice and data along with Mobility Management, VLR functionality and



SignalingInterface

Module - N

T1/E1

T1/E1

T1/E1

T1/E1

Additional card will scale

the system upwards

standby card, but load

sharing, for the N+1 load

shared redundancy

Signaling

Interface

Module

T1/E1

T1/E1

42



Additional cards in

a protection group

will scale the

system upwards

protection group -1 protection group -2 protection group -3

Call

Processing

Module - N

Call

Processing

Module - N

Call

Processing

Module - N

stanby card, but not load

sharing, for the 1+1

redundancy

Signaling Gateway (ISUP) functions. These modules operate in active or standby mode with N+N redundancy. For scaling the call processing function, protections groups will have to be added to increase the capacity.

Figure 21. CCM module scalability

The system is modeled taking into account the characteristics of each component used in the system. The theoretical model is then populated with lab measurement data for model calibration. Once the system model is calibrated then the typical call model and traffic profile is used to determine each component capacity as well as the system capacity. Each component in the system is provisioned for 80% of its full load.

Under normal operating condition, each component of the system is provisioned to a maximum of 80% of its full load. The overload condition triggers when the CPU exceeds 80% of its full load. The overload condition trigger is configurable.

4.0 Netra Wireless Soft Switch System

The Netra-based system uses the Sun Microsystems Netra 240 server to provide more memory and processing speed than the standard 500/650 MHz package. Currently, Alcatel provides three models of the Netra-based system: Model A, Model B, and Model C. These models differ in the number of SIM cards and Netra pairs they contain. The proceeding sections provide more information about the Sun Netra 240 server as well as the different model configurations.

43

Note: All discussion of card types, descriptions, and scalability that are discussed in Section 2.0 & 3.0 above are also valid for the Netra system. 4.1 Netra 240 Server Specifications Netra 240 Hardware Specs

Operating System: Solaris 8

Processor: Up to two 1.28-GHz

UltraSPARC IIIi processors

Main Memory: 4 GB DDR-1 SDRAM

(PC2100) 128-bit plus ECC memory

Network: Four 10/100/1000-Mbps BaseT

Ethernet ports Figure 22. Netra 240

Server

DVD R/W Drive

Internal disk: Up to two 3.5-in. x 1.0-in., 15K RPM, 73-GB Ultra160

SCSI hot-swappable drives

Telecom Environment Certification: Telcordia GR-63 CORE, GR-1089-

CORE, SR 3580 NEBS Level 3

Dry contact relay alarms with alarm indicators

ALOM (Advanced Lights Out Manager) enables you to monitor and

control your server over either a serial connection (using the SERIAL

MGT port), or Ethernet connection (using the NET MGT port).

Cooling blowers and a replaceable air filter

Expansion bus: Three 64-bit PCI 2.2-compliant expansion slots

One 33-MHz or 66-MHz full-length slot

Two 33-MHz half-length slots

44

4.2 Netra Model A Configuration

The model A configuration is primarily used in lab environments for minimum traffic scenarios. The current model A configuration uses 2+1 SIM cards, 1+1 DDM Netras, 1+1 CCM Netras, and 1+1 SAM Netras. Please see below for more information about this configuration.

Figure 23. Model A Netra Configuration

2 SAM Netras (Shelf 5 and 6)

2 DDM Netras

(Shelf 7 and 8)

2 CCM Netras

(Shelf 18 through 19)

Terminal Server

(Shelf 4)

WSS Chassis

Intake

PDU –48VDC

A and B Feed

3 SIM

Cards

(Shelf 1)

Fan

2 Cisco Ethernet

Switches

(Shelf 2 and 3)

45

4.3 Netra Model B Configuration The model B configuration is used in medium traffic scenarios. The current model B configuration uses 5+1 SIM cards, 1+1 DDM Netras, 3+3 CCM Netras, and 1+1 SAM Netras. Please see below for more information about this configuration.

Figure 24. Model B Netra Configuration

2 SAM Netras

6 SIM

Cards Fan

6 CCM Netras

2 DDM

Netras

Intake

WSS Chassis

Terminal Server

PDU –48VDC

A and B Feed

2 Cisco Ethernet Switches

46

4.4 Netra Model C Configuration

The model C configuration is used in commercial or heavy traffic scenarios. The current model C configuration uses 7+1 SIM cards, 2+1 DDM Netras, 5+5 CCM Netras, and 1+1 SAM Netras. Please see below for more information about this configuration.

Figure 25. Model C Netra Configuration

This was all about the WSS. As shown, WSS is the central device and controls all the other devices. WMG and WEM are discussed in further chapters.

8 SIM

Cards

Fan

2 Cisco Ethernet

Switches

PDU –48VDC A and B Feed

Intake

Terminal Server

2 SAM

Netras

10 CCM

Netras

WSS Chassis

3 DDM Netras

48

Wireless Media Gateway UNIT 1

Chapter 4

1.0 Introduction

Till now we have discussed about the WSS of the Spatial Atrium. Actually, it is the WSS which controls the WMG. WMG devices are generally installed close to the user‘s area and WSS is the central device. This can be seen in the diagram given in the 1st chapter. Now the project we are talking about i.e. installing BSS Local Switching is actually done in the WSS part and not in the WMG. WMG only acts as the transporter which sends the data to the WSS for further transmission. In this chapter we will study about the WMG as it forms an important part of the concerned product Spatial Atrium.

2.0 Wireless Media Gateway Hardware System

The Wireless Media Gateway (WMG) provides physical network access for bearer. The WMG switching fabric is optimized for ATM, IP and time division multiplex (TDM) interworking. It provides transparent capabilities and supports different signaling protocols, such as ATM User Network Interface (UNI), IMA and PNNI.

Front View Rear ViewFront View Rear View

Figure 26. WMG Unit, Front & Rear view

Access resources, such as echo cancellation, are integrated into the WMG hardware as pooled resources. The control interface is entirely standards based. The figure above shows a front and rear view of the WMG unit The figure below shows a close-up view of the rear of the WMG BITS clock and alarm connections. Figure 27. Alarm & Timing source

T1/E1

Bits Clock

AlarmsT1/E1

Bits Clock

Alarms

49

The Spatial Atrium supports a number of TDM interfaces, including: a) E1 b) STM-1 c) T1 d) DS-1 e) DS-3 f) OC-3

ATM-based interfaces include:

a) DS-1 (Inverse Multiplexing over ATM) b) DS-3 c) OC-3c d) STM-1c e) OC-12c f) STM-4c

3.0 WMG SuperSlots Design

The Spatial Atrium provides capacity increases through the use of SuperSlots. Each board connected through the mid-plane has a SuperSlots design to permit numerous configurations. Channelized interface cards, which reside in the rear slots (21-27 and 34-40), can accommodate two SuperSlot cards and the ATM interface cards (slot 28+29 and 32+33) can accommodate four SuperSlot cards. The SuperSlot cards connect to the channelized and ATM interface cards, which in turn connect directly to the mid-plane. System cards, which include data server and Voice Server cards, and control cards, which include the Control Module, Packet Matrix and Service Matrix reside in slots 1 - 20. WMG Cards & Slot Assignment The WMG is designed so that the boards are serviceable from both the front and rear. WMG slot assignment shows the slot assignments of each board and how they connect to the mid-plane in the center of the WMG. Slots 1-20 connect to the front of the mid-plane and slots 21-40 connect to the rear of the mid-plane. The dimensions for boards in slots 1-20 are 400cm x 400 cm; the dimensions for boards in slot s 21-40 are 200cm x 400cm. They are multi-layered to ensure they are firm for insertion and ejection. Each board has two LEDs to indicate the board status and board faults. Figure below shows the WMG Slot Assignments.

50

Control Cards

CM – Control Module

PM – Packet Matrix

SM – Service Matrix

CI

(r)

CI CI CI CI AI

(a)

AI

(a)

AI

(r)

CIor

AI

(r)

CI CI CI CI CI

VS

orDS

VS

orDS

VS

orDS

VS

orDS

(a)

CM

(a)

PM

(a)

PM

(a)

SM

(r)

SM

(r)

PM

(r)

PM

(r)

CM

VS

orDS

VS

orDS

VS

orDS

VS

orDS

CIor

AI

(r)

CIor

AI

(a)

CIor

AI

(a)

(r)

2140AI

(a)

AI

(r)

AI

(r)

VS

orDS

VS

orDS

VS

orDS

VS

orDS

21 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

222324252627282930313233343536373839

Mid-Plane

System/Common Cards

DS – Data Server Card

VS – Voice Server Card

Interface Cards

CI – Channelized Interface

AI – ATM Interface

Control Cards




CI

(r)

CI CI CI CI AI

(a)

AI

(a)

AI

(r)

CIor

AI

(r)

CI CI CI CI CI

VS

orDS

VS

orDS

VS

orDS

VS

orDS

(a)

CM

(a)

PM

(a)

PM

(a)

SM

(r)

SM

(r)

PM

(r)

PM

(r)

CM

VS

orDS

VS

orDS

VS

orDS

VS

orDS

CIor

AI

(r)

CIor

AI

(a)

CIor

AI

(a)

(r)

2140AI

(a)

AI

(r)

AI

(r)

VS

orDS

VS

orDS

VS

orDS

VS

orDS

21 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

222324252627282930313233343536373839

Mid-Plane

System/Common Cards



Interface Cards



Control Cards




CI

(r)

CI CI CI CI AI

(a)

AI

(a)

AI

(r)

CIor

AI

(r)

CI CI CI CI CI

VS

orDS

VS

orDS

VS

orDS

VS

orDS

(a)

CM

(a)

PM

(a)

PM

(a)

SM

(r)

SM

(r)

PM

(r)

PM

(r)

CM

VS

orDS

VS

orDS

VS

orDS

VS

orDS

CIor

AI

(r)

CIor

AI

(a)

CIor

AI

(a)

(r)

2140AI

(a)

AI

(r)

AI

(r)

VS

orDS

VS

orDS

VS

orDS

VS

orDS

21 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

222324252627282930313233343536373839

Mid-Plane

System/Common Cards



Interface Cards



Figure 28. WMG Slot Assignments Each board has two LEDs to indicate the board status and board faults. The WMG is comprised of the following cards/ boards:

Mid-plane Up to 12 data server cards (DS)

Control cards: Interface cards: 2 Control Modules (CM) Up to 14 channelized interfaces (CI) 2 Service Matrixes (SM) Up to 4 ATM interfaces (AI) in 10GB

system 2 Packet Matrixes (PM) Up to 12 Voice Server cards (VS)

4.0 WMG Mid Plane

All boards on the WMG plug into the mid-plane. The mid-plane provides connectivity and power and ground to all cards in the WMG. The mid-plane‘s primary functions are to provide point-to-point connectivity, power, and logic and physical grounds for all control and Network Interface Cards (NIC). Many extra connection paths are also provided, which enable the various board level redundancy schemes employed by the WMG. The mid-plane has 40 card slots. The slots are numbered from left to right (either facing the front or facing the rear), 1 to 20 across the front and 21 to 40 across the rear. Each slot supports a certain type of WMG card, with each slot designed to hold a specific card or card type. The front of the mid-plane (slots 1-20) provides the slots for the Spatial Atrium control cards and common cards, while the rear (slots 21-40) provides the slots for the interface cards.

51

MidplaneMidplane

Mid-Plane

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

AI

(a)

2.5Gb

AI

(a)

2.5Gb

AI

2.5Gb

CI

AI

4K2.5K

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS CM SM SM CM

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

CI

AI

4K2.5K

CI

AI

(a)4K

2.5K

CI

AI

(a)4K

2.5K

(r)(r)

AI

2.5Gb

(r) (r)(r)

PM PM PM PM

40 39 38 37 36 35 34 3233 30 29 28 27 26 25 24 23 22 21

2019181716151413121110987654321

31

Mid-Plane Slot Capacities for 10 GB Configuration

Mid-Plane

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

AI

(a)

2.5Gb

AI

(a)

2.5Gb

AI

2.5Gb

CIAI

4K2.5K

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

8K622Mb

VSor

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8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS CM SM SM CM

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

CIAI

4K2.5K

CIAI

(a)4K

2.5K

CIAI

(a)4K

2.5K

(r)(r)

AI

(a)

2.5Gb

AI

2.5Gb

AI

2.5Gb

(r)(r)

4K622Mb

VSor

DS

4K622Mb

VSor

DS

4K622Mb

VSor

DS

4K622MB

VSor

DS

(r)(r)

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Mid-Plane

CI

8K

CI

8K

CI

8K

CI

8K

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(a)

2.5Gb

AI

(a)

2.5Gb

AI

2.5Gb

CI

AI

4K2.5K

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS CM SM SM CM

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS

CI

AI

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AI

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31


Mid-Plane

CI

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CI

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CI

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CI

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2.5Gb

AI

(a)

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AI

2.5Gb

CIAI

4K2.5K

CI

8K

CI

8K

CI

8K

CI

8K

CI

8K

8K622Mb

VSor

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8K622Mb

VSor

DS

8K622Mb

VSor

DS

8K622Mb

VSor

DS CM SM SM CM

8K622Mb

VSor

DS

8K622Mb

VSor

DS

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VSor

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4K2.5K

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2.5Gb

(r)(r)

4K622Mb

VSor

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VSor

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VSor

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VSor

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(r)(r)

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40 39 38 37 36 35 34 32 3133 30 29 28 27 26 25 24 23 22 21

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Mid-Plane

CI

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CI

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CI

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AI

(a)

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2.5Gb

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AI

4K2.5K

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CI

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CI

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VSor

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VSor

DS

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DS CM SM SM CM

8K622Mb

VSor

DS

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VSor

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VSor

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VSor

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AI

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31

Mid-Plane

CI

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CI

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Mid-Plane

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Mid-Plane

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Figure 29.WMG Cutaway view

These slots are specifically configured for interface cards so that all interface cabling is in the rear of the machine, leaving the front of the WMG unobstructed. As shown in the figure below, some slots support more than one type of card. The WMG can be configured as a 10-GB system. The figure shown below depicts the Mid-Plane Slot Capacities for 10 GB Configurations. In the later sections, various cards are discussed in detail.

Figure 30. Mid-Plane Slot Capacities for 10 GB Configuration

52

5.0 Control Module Card (CM)

The Control Module is responsible for managing and controlling resources within the WMG and communicating with the WSS for call control, maintenance, and configuration instructions. It is a redundant pair and resides in slots 7 and 14 of the mid-plane. Figure 31. Control Module Card

The Control Module supports three configurations. In addition to the base configuration, the Spatial Atrium supports SuperSlots, which increase the Control Module‘s capabilities. 5.1 Basic Configuration The Control Module‘s basic configuration includes the following:

a) Motorola 755/500 MHz based five-processor system

b) 672 HDLC channels for PRI and GR-303 signaling CPU Configuration The Control Module‘s basic configuration provides five central processing units (CPUs) that perform specific system functions. These CPUs include:

c) Master CPU d) Facility CPU e) Connection/Resource CPU f) Narrowband Signaling CPU g) Broadband Signaling CPU

Each of the five dedicated CPUs has its own persistent flash memory and the

software runs on top of the pSOS operating system. Master CPU The master CPU is responsible for the following functions:

h) Communicating directly with the WSS i) Performing OA&M validations j) Decoding SNMP requests

53

k) Routing messages between ATM (broadband signaling)- and voice-connecting (Narrowband Signaling) CPUs

Along with providing the OA&M management functionality for the WMG, the Master CPU is also the point of communication between the WMG and the WSS. All messages from the WSS to the WMG are distributed through the Spatial Atrium‘s Ethernet switch to the correct WMG destination (such as signaling, configuration and management) by the Master CPU. The Master CPU communicates with all of the CPUs. Connection/Resource Manager CPU The connection/resource software provides the WSS the ability to manage specific subscriber connections within a call. The connection/resource manager is responsible for the following functions:

Allocating some resources Establishing physical connection types for each call

The WSS communicates with the connection/resource manager. The connection/resource manager allocates physical resources (at the DS-0 level) as specified by the WSS. It receives instructions from the Control Module and then instructs the facility manager to allocate the appropriate resources. The connection/resource manager also determines where to route the signaling for the connection. If the connection is TDM, the connection/resource manager instructs the facility manager to forward the information to the narrowband signaling CPU. If the signal is ATM, the connection/resource manager connects the signaling cells to the Broadband signaling CPU. The connection/resource manager also communicates directly with the Voice Server and data server cards to create paths between TDM and ATM terminations. Facility CPU The Facility CPU is responsible for the following functions:

Managing Service Matrix Managing network interface cards Controlling tone, announcements, caller ID, echo cancellation,

bridges, and MF/DTMF receiver DSPs Managing ATM interface tasks Monitoring interface ports for errors and some transmission

alarms The facility manager communicates with the Service Matrix and the network interface cards. It sets up paths for narrowband signaling and contains the digit maps to set up single connections for narrowband signaling.

54

5.2 Control Module Configuration The Control Module‘s basic configuration supports 672 HDLC channels. When one SuperSlot is added to the Control Module, it can support an additional 1,344 HDLC channels, providing a total of 2,016 HDLC channels per WMG. The figure below illustrates how the CPUs communicate between each other, the other components of the WMG and the WSS. Figure below provides an overview of the WMG Card.

Figure 32. WMG Card Overview

6.0 Service Matrix Card (SM)

The Service Matrix is the Spatial Atrium switch‘s TDM fabric. Its primary responsibility is to provide switching functionality for the DS-0s. Following figure shows the Service Matrix board.

55

Figure 33. Service Matrix Card

The Service Matrix is a redundant pair and resides in slots 10 and 11. Each Service Matrix is bus-connected to all Control Modules, channelized interface slots, Voice Server cards and data server cards. This design provides redundancy and load sharing for quick switchover and recovery. The Service Matrix has a capacity of 128,000 DS-0s. The DS-0s are managed in a single stage, fully cross-connected matrix. All switching through the Service Matrix is performed at the DS-0 level. The Service Matrix DS-0 buses are allocated to specific mid-plane slots, with 4,000 or 8,000 DS-0s allocated to every channelized interface card slot and 4,000 DS-0s allocated to every Voice Server card slot. The Service Matrix also provides the following shared resources using three SuperSlots:

Service Matrix Resource

Resource Maximum Value

DTMF/ MF Receivers

1,280 receivers (256 MF and 1024 DTMF)

Three- Way Bridges

1, 000 three- way bridge circuits

Announcements 1,024 announcements (the Spatial Atrium provides 66 default announcements scripts) The SDRAM supports 2097 seconds (34.95 minutes). The speech segments must be an integer multiple of 2048 DS- 0s in length. Any DS- 0 locations not filled by the speech segment are filled with silence and that portion of the announcement storage space is lost.

Caller ID 512 channels

Tones 256 channels

Echo Cancellation 1,536 channels

56

6.1 Echo Cancellation Echo cancellation is performed by system hardware and is accessed by the system as a pooled resource. Echo cancellers are available on the Service Matrix for three-way calls. Echo cancellation schemes supported by the Spatial Atrium include:

G.168 – ITU-T standards for digital network echo cancellers G.165 – ITU-T standards for echo cancellers V.25 and V.8 – ITU-T recommendations specifying tone disable

characteristics V.8 bis – low-speed series of V-modems that do not send echo

canceller disable tone Echo cancellation features supported by the Spatial Atrium include:

Control and Test per DS-0 ERLE (Echo Return Loss Enhancement) ERL (Echo Return Loss) Convergence less than 150 ms Double Talk Detection Noise Matching 128 ms Tail Delay

6.2 System Testing The Service Matrix is also responsible for the Spatial Atrium‘s clocking references. Clock synchronization source inputs to the system are through building integrated timing supply (BITS) timing or from a synchronous transmission facility connected externally. The primary reference source is BITS. The Spatial Atrium switch also has a secondary BITS reference source, an OC-3 tertiary reference source, and uses a stratum-3 network clock as its emergency timing source. The Spatial Atrium supports timing from the following external interfaces:

Channelized DS-3 interface card T1, E1, OC-3, or STM-1 facilities designated as timing synchronization

spans Multiple timing facilities are located in the WMG. The WMG with the timing spans is designated as the master WMG for synchronization purposes.

Each WMG has a stratum-3 network clock. Each clock in the Spatial Atrium is synchronized to the same stratum clock.

57

7.0 Packet Matrix Card

The Packet Matrix is the Spatial Atrium‘s ATM fabric. It is responsible for directing the flow of packetized traffic (both voice and data) through the Spatial Atrium switch. Following figure shows the Packet Matrix board. Figure 34. Packet Matrix Card The Packet Matrix is a redundant pair that resides in slots 8 and 9 (actives) and 12 and 13 (redundant s). Each pair of cards switches 10 GB. The Packet Matrix has paths to Control Module card slots, all Server card slots, and all ATM interface card slots. The redundant SuperSlots card types must be the same card types as the active SuperSlots. All SuperSlots are field upgradeable and can be replaced without affecting other SuperSlots.

8.0 Voice Server Cards

Voice server cards are responsible for translating between channelized voice data and cell-based voice data. Following figure shows the Voice Server board.

Figure 35. Voice Server Card

58

Voice server cards, which are load sharing, are configured for N + 1 redundancy. The redundant card is configured so it can assume the processing duties in the event either Voice Server cards fails. Load sharing is controlled by the Control Module, which sets up the path between the Voice Server cards and the Service Matrix. Every Voice Server slot has a path to the Control Module, Service Matrix and Packet Matrix. The Voice Server cards support ATM adaptation layers 2 (AAL-2) for voice services and uses AAL-5 service to communicate with the Control Module. The Voice Server card‘s basic configuration supports 2,000 AAL-2 channels by using the appropriate VS card, e.g. VSM2 or VSM3. Echo cancellers are available on the Voice Server card for voice calls. The base configuration supports 480 channels of ADPCM voice compression and 1,056 channels of echo cancellation. The expanded Voice Server card configuration supports 1,536 channels of echo cancellation.

9.0 Channelized Interface Card

The Spatial Atrium switch supports the following channelized interfaces:

E1 T1 STM-1 DS-3 OC-3

The channelized interface cards provide TDM networks with access to the Spatial Atrium switching system. The cards have a bus connection through the Mid-Plane directly to the Service Matrix, which has the responsibility of breaking the signal down to the DS-0 or N x DS-0 and switching the information to its destination. The system supports a 60 T1 or E1 ports interface card with N+1 redundancy. The channelized T1/E1 cards can reside in slots 21-27 and 34-40. The Spatial Atrium provides superior density by supporting DS-3/OC-3 channelized interface adapters. The channelized interface adapters consist of a six-port DS-3 (coaxial) and a two-port OC-3 (single-mode fiber optics). The DS-3/OC-3 channelized interface adapters have two SuperSlots that can support either two DS-3 interfaces or two OC-3 interfaces. The channelized T1/E1 interface card is shown in following figure.

59

Figure 36. Channelized T1/E1 Interface Card

Following figure illustrates the channelized DS-3/OC-3 interface card with the channelized interface DS-3 and OC-3 SuperSlots design.

Figure 37. Channelized DS-3/OC-3 Interface Card and SuperSlots

A channelized interface adapter cannot host both types of SuperSlot interfaces simultaneously. The Spatial Atrium supports 2,016 channels per SuperSlot. With both the channelized SuperSlots, the channelized DS-0 capacity is 4,032. The DS-3 SuperSlot interface card provides the Spatial Atrium switch with high-bandwidth copper connectivity. The DS-3 SuperSlot has three DS-3 links and an overall bandwidth of 2,016 DS-0s per card. Six bayonet locking

OC3 CARD DS3 CARD

OC3 SuperSlot

DS3 SuperSlotDS3/OC3 Interface Card

OC3 CARD DS3 CARD

OC3 SuperSlot

DS3 SuperSlotDS3/OC3 Interface Card

60

connector (BNC) coaxial connectors are housed on each card: a send and receive pair for each DS-3 link. The DS-3 has a 1:1 redundancy scheme at the SuperSlot level, so the backup card is configured exactly like the active card. DS-3 can also be configured with N+1 redundancy. The OC-3 SuperSlot Interface card provides the Spatial Atrium switch with fiber-optic connectivity based on the SONET specification. It hosts one OC-3 slot and provides a channelized capacity of 2,016 DS-0s per card. The redundancy scheme for the OC-3 SuperSlot is 1:1, so the backup card is configured exactly like the active card. Every WMG in the Spatial Atrium provides up to 14 channelized interface card slots. It accommodates any combination of channelized interfaces (T1, E1, STM-1, DS-3, OC-3) in those 14 slots. Following table shows the capacity of each component in WMG.

Capacity of various WMG components

Card Type Capacity Description

CM The CM provides capacity for 2,016 HDLC channels per WMG

SM The SM has a TDM switching matrix with a capacity of 128kx128k DS-0s

PM PM1 supports a fully redundant 10G packet fabric

VS2 Without ADPCM, 2044 AAL2 (G.711) channels with echo.

VS2 With ADPCM, 512 AAL2 (G.711) channels with echo or 1408 AAL2 (G.726) channels with echo.

VS3 With VoIP, 2044 channels with echo.

VS4 With AMR and Iu User Plane procedure support for UMTS.

ES Echo Server (ES) modules provide echo cancellation of 4,032 channels

CI DS-1 CI module supports a capacity of up to 1,440 DS-0s E1 CI module supports a capacity of up to 1,920 DS-0s DS-3 CI module supports a capacity of up to 4,032 DS-0s OC-3 CI module supports a capacity of up to 4, 032 DS-0s

AI The maximum capacity of an ATM interface module is 2.5 Gbps

Ethernet Each Ethernet switch has 24 ports

61

9.1 Optical Ports The optical ports are 1310 nm SC duplex intermediate reach (IR) receptacles. The single mode fiber cable must have SC connectors on the equipment side. Figure 38. Fiber optic cable

10.0 ATM Interfaces

ATM interface cards provide the Spatial Atrium switch with access to ATM networks and have 1 + 1 redundancy. ATM networks include user access devices such as digital subscriber line access multiplexers (DSLAMs) (which use ATM UNI), as well as network connectivity with other ATM UNI and ATM PNNI data streams. ATM interface cards interact directly with the Packet Matrix. Four ATM interface slots are available on each WMG, with two being active and two being redundant. The maximum capacity of an ATM interface card is 2.5 Gbps. The ATM interface cards reside in slots 28 to 33 across the rear of the mid-plane. Slots 28, 29, 32 and 33 are optional for either ATM or channelized interface cards. The ATM interface cards are hosted by an ATM interface adapter card, which resides in the ATM interface slots on the mid-plane. Following figure shows the ATM interface card configured with DS-3, OC-3c, STM-1c, STM-4c and OC-12c SuperSlot interface cards. Figure 39. ATM Interface Card

DS-3 SuperSlot

Interface Card

OC-3c SuperSlot

Interface Card

OC-12c SuperSlot

Interface Card

OC-12c SuperSlot

Interface Card

62

Each ATM interface card has four SuperSlots to accommodate SuperSlot Interface cards, which provide interface capabilities to:

a) DS-3 – 16 port counts b) OC-3c – 16 port counts c) OC-12c – 4 port counts

The ATM interface card supports a mixed configuration of SuperSlots. For example, an ATM interface card can accommodate two OC-3 SuperSlots and two DS-3 SuperSlots. The DS-3 SuperSlot interface card supports four DS-3 interfaces. Up to four DS-3 SuperSlot Interface cards can reside in a single ATM interface card, which provides the Spatial Atrium with up to 16 DS-3 interfaces per ATM interface card. The OC-3c SuperSlot interface card supports four OC-3c interfaces. Up to four OC-3c SuperSlot interface cards can reside in a single ATM interface card, which provides the Spatial Atrium with up to 16 OC-3c interfaces per ATM interface card. The OC-12c SuperSlot Interface card supports one OC-12c. Up to four OC-12c SuperSlot interface cards can reside in a single ATM interface card, which provides the Spatial Atrium with up to four OC-12c interfaces per ATM interface card. Each ATM interface card can be configured with any combination of SuperSlot interface cards. The Spatial Atrium supports up to 8 active SuperSlot interface cards residing in up to two active ATM interface cards. The Spatial Atrium supports up to two redundant ATM interface cards that must be configured with the identical combinations of SuperSlot interface cards as their active counterparts. For example, the redundant ATM interface card in slot 28 must be configured exactly like the active ATM interface card in slot 33. 10.1 Optical Ports The optical ports are 1310 nm LC duplex intermediate reach (IR) receptacles with clock and data recovery (CDR). The single mode fiber cable must have LC connectors on the equipment side. Figure 40. Fiber optic cable with LC Connector

11.0 Bearer Traffic Flow The figure below shows how traffic flows between the boards on the WMG.

63

Figure 41. Inter CPU Communication

The TDM data passes through the channelized interface card, which unbundled the information at the DS-0 level. The channelized interface card then passes it to the Service Matrix for further switching. If the information has a TDM destination, the Service Matrix switches the data and returns it to the appropriate TDM interface. If the data has an ATM destination, the Service Matrix switches the data and forwards it to the Server card. The Server card translates the TDM data to ATM packetized data, and then forwards it to the Packet Matrix, which provides virtual circuit connectivity and switching. The data is then delivered to the ATM interface cards, which in turn sends it to the data network and on to its destination. If the IP traffic has a TDM destination, the AI card routes the call to the PM card. The PM card converts IP traffic to TDM traffic and routes it to the VSM. The VSM sends the call to the TDM network where it is routed to its final destination. VoIP or ATM traffic, or data with an ATM source and destination, passes through the ATM interface board to the Packet Matrix. The Packet Matrix routes the ATM information. The Packet Matrix returns the data to the appropriate ATM interface for delivery.

64

Calls with an ATM source and a TDM destination flow through the WMG in the reverse order of the TDM-origination to ATM-destination flow. The data is switched by the Packet Matrix, and then is forwarded to the voice server card, which translates the data to TDM. The typical flow for ATM to TDM for a UMTS call scenario is shown below:

Figure 42. Bearer flow ATM to TDM (UMTS Scenario)

Now this was all about the WMG. WMG (many in fact) is connected to the central WSS. These WMGs are towards the distant areas and connected to WSS to provide connectivity.

TDM

NIC

TDM

NIC

Packet

Matrix

VoIP

AAL2

AAL1DSP

TSI

VoIP

AAL2

AAL1DSP

TSI

TDM

NIC

TDM

NIC

ATM

NIC

Packet

Matrix

VoIP

UMTS

VoATM

DSP

TSI

VoIP

UMTS

VoATM

DSP

TSI IPNIC

DTMF

CALEAAnnounce-

ments

Conference

Bridging

Voice Server Cards

Matrix

TDM

VoIP/MPLS

VoIP/ATM

VoATM

VoIP

TDM

NIC

TDM

NIC

Packet

Matrix

VoIP

AAL2

AAL1DSP

TSI

VoIP

AAL2

AAL1DSP

TSI

TDM

NIC

TDM

NIC

ATM

NIC

Packet

Matrix

VoIP

UMTS

VoATM

DSP

TSI

VoIP

UMTS

VoATM

DSP

TSI IPNIC

DTMF

CALEAAnnounce-

ments

Conference

Bridging

Voice Server Cards

Matrix

TDM

Matrix

TDM

VoIP/MPLS

VoIP/ATM

VoATM

VoIP

Spatial Media Gateway

ATM-to-TDM

66

Wireless Element Management UNIT 1

Chapter 5

1.0 Introduction

The Alcatel Spatial Atrium DMSC Wireless Element Management (WEM) system offers fully integrated OAM&P of the call server and media gateway. Provisioning and monitoring of both elements can be managed from the WEM, eliminating potential inconsistencies and errors between call servers and media gateways. This significantly reduces the operational burden and eliminates unnecessary system management complexity. All the details of Alcatel WEM are provided in the subsequent sections.

2.0 Wireless Element System

The Alcatel WEM is the Element Management System application and provides the interface for the FCAPS (Fault, Configuration, Accounting, Performance and Security) functionality of the complete Alcatel solution. The WEM design is based on client/server architecture. The Alcatel WEM consists of two main components one the WEM server and the WEM client. The WEM server is the Element Management System application that resides in the WSS to provide the FCAPS services to the mobile operator‘s OSS. The WEM client is the GUI and runs on a UNIX or Windows 2000 platform. The WEM GUI serves as the primary interface for operators to control and monitor the Alcatel Platform. The GUI can be connected to the WEM server locally or remotely. Figure 43 shows the Alcatel WEM Architecture. Citrix Metaframe creates a centralized and managed environment for WEM client access. Administrators configure Citrix to have WEM clients shared, so users do not have to install WEM client on their own workstations. Users do not have do worry about the installation problem and requirement of WEM clients; instead, users can access WEM client via Citrix client and leave installation issues to administrators. Administrators manage WEM clients easily in a centralized Citrix server. Whenever WSS or WEM client software changes, administrators make the adjustments only on the Citrix server. Another advantage of the Citrix server is that the server maintains user information and user directory on disk space of server.

67

Figure 43. Alcatel WEM Architecture

Command Line Interface (CLI) to the WEM enables the user to configure the Spatial Atrium system by a executing a few commands bypassing all the steps in the GUI. CLI incorporates changes directly in the databases. Alcatel WEM provides following functionalities:

Fault management – Provides the user with the information needed to troubleshoot and maintain the Alcatel system. It supports displaying, filtering and querying alarms and events.

Configuration management – Allows the user to make sure that all

resources are in the appropriate administrative state and processing calls as designed. It can lock and unlock modules, modify resource configurations and provides procedures that are important for system maintenance.

Secure

SAM Module

Java

RMI

CLI over

CORBA v2.3

SNMP v2

WSS Platform

DB

WEM (OAM&P) Service

Logic

CCM-n

WMG-n …

…

WMG-2

WMG-1

SIM-n

SIM-1

ESM-2

ESM-1

PSM-3

PSM-2

DDM-n

DDM-1

CCM-2 CCM-1

PSM-1

TCP/IP

SNMP

GUI Client

CLI Client

NMS

CORBA

Operator’s

OSS

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Accounting management – Allows the user to query and manage CDRs and ensures that billing functions are operating as designed.

Performance management – Allows the user to monitor system

statistics to ensure that the system is operating with optimum effectiveness. The user can view the system components‘ performance information and quality of service.

Security management - Allows a security administrator to establish

and configure settings for the Alcatel system. Permits administration of various levels of security for users who have access to the WEM GUI, setting user‘s authentication parameters (passwords, user groups and user profiles).

NOC Interface: Spatial Atrium sends SNMP Traps on the northbound systems in real time. The Traps provide information about the severity, cause, corrective action, and description of the Alarm. Additionally, the Northbound systems can query the Spatial Atrium on a periodic basis to pro-actively get its Status. Spatial Atrium has the MIB definitions for the Trap MIBs that can be integrated in the Northbound system. Spatial Atrium can also send the performance measurement data collected on a periodic basis to Northbound OSS systems. The frequency of these data transfers can be configured through WEM for different measurements. It also supports collection of these measurements on a real time basis through SNMP queries. Spatial Atrium provides SNMP based Configuration capabilities that the Northbound Systems can take advantage of to provision Spatial Atrium. These messages are typically SET and GET requests. Spatial Atrium has a set of MIBs for integration with the Northbound systems. Security: The WEM application allows none / read / read-write permission to be granted for all major functional areas. System access can be restricted to prevent a service affecting access level user from gaining access to system administration and security profiles.

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Fortune @ Bottom of the Pyramid UNIT 2

Chapter 1

1.0 Introduction

In economics, the bottom of the pyramid is the largest, but poorest socio-economic group. In global terms, this is the four billion people who live on less than $2 per day, typically in developing countries. The phrase ―bottom of the pyramid‖ is used in particular by people developing new models of doing business that deliberately target that demographic, often using new technology. This field is also often referred to as the "Base of the Pyramid" or just the "BoP".

The phrase ―bottom of the pyramid‖ was used by U.S. president Franklin D. Roosevelt in his April 7, 1932 radio address, The Forgotten Man, in which he said ―These unhappy times call for the building of plans that rest upon the forgotten, the unorganized but the indispensable units of economic power...that build from the bottom up and not from the top down, that put their faith once more in the forgotten man at the bottom of the economic pyramid.‖ The more current usage refers to the 4 billion people living on less than $2 per day, as first defined in 1998 by Professors C.K. Prahalad and Stuart L. Hart. It was subsequently expanded upon by both Prahalad in 2004 in The Fortune at the Bottom of the Pyramid and by Hart in 2005 in Capitalism at the Crossroads. Prahalad proposes that businesses, governments, and donor agencies stop thinking of the poor as victims and instead start seeing them as resilient and creative entrepreneurs as well as value-demanding consumers. He proposes that there are tremendous benefits to multi-national companies who choose to serve these markets in ways responsive to their needs. After all the poor of today are the middle-class of tomorrow. There are also poverty reducing benefits if multi-nationals work with civil society organizations and local governments to create new local business models.

2.0 Bottom of the Pyramid (BoP)

The distribution of wealth and the capacity to generate incomes in the world can be captured in the form of an economic pyramid. At the top of the pyramid are the wealthy, with numerous opportunities for generating high levels of income. More than 4 billion people live at the BOP on less than $2 per day. This can be depicted in the form of a pyramid which Prahalad has incorporated in his book. The pyramid has 4 blocks (can be more or less depending upon the interpretation) each representing a different class of the society from rich to the very poor. In context of India, this pyramid is shown below:

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Rich 100m

n

Middle Class

400 mn

Poor Class 350 mn

“BoP”

Below Poverty Line-No buying capacity

400-500 mn

mn=million

Target Class

Figure 47. Bottom of Pyramid

The above pyramid is a depiction of Prahalad‘s Bottom of Pyramid. Following are the interpretations of this model:

Rich people constitute the 100mn population of the society. Middle class constitutes the 400mn population of the society. Poor class constitutes the 350 mn population of the society which is

actually the Bottom of the pyramid. Rest population of 400-500 mn people lives below poverty line so

doesn‘t have any buying capacity It is this Poor class of 350 million people that Prahalad is referring. According to him, if the companies can provide the products in the buying capacity (small shampoo sachet etc.) of poor, then they can actually earn revenue and expand their market. If we talk about the telecom companies, then to start service in a region requires huge amount of money. Companies invest because they expect a huge return on investment (ROI). However companies do not invest in rural India because people cannot pay much for these services though they feel a demand for it. Now as other areas are facing saturation, companies have no option but to look at this bottom. So there is a need of innovation in terms of investment so that cost can come down and services could be provided

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benefiting both the company and the people. It is this innovation that is discussed in this unit.

3.0 Indian Telecommunication Scenario

As with the other sectors, Telecommunications sector is also facing the falling revenues. So, as the developed mobile markets all over the world approach saturation, the industry has begun to consider ‗the next billion‘ users. These are the rural populations living beyond the reach of traditional communications networks of any kind. Rural India is a prime example of the opportunity as shown below:

A huge population – Over 1000 million people in 630,000 villages across 3.2 million square miles.

A massive economy – over 50% of India‘s total GDP. There are almost same number of middle to high income households in rural areas (21.16 mn) as urban India (23.22 mn).

A parallel economy – with the same needs as developed markets but a reduced ability to pay.

The rural consumer in India cannot pay the $50 per month typical of London, Tokyo and Sydney. Nor can they pay the $7-10 per month typical of Delhi and Mumbai. But research and experience shows that they can and will pay around $2 per month today – even before the impact of communications increases their ability to pay. The challenge is to deliver a mobile service to rural users that can not only be viable, but be profitable at these low levels of Average Revenue Per User (ARPU). Currently, the mobile phone population in India is growing by 13 million phones per month. The overall teledensity is 35.65%. Urban teledensity is 86.18% but rural teledensity on the other hand is just 14.36% (source: Feb 2009 release, Department of Telecommunications, GOI).

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The reason for such a large difference in the number of urban & rural teledensity is simple: current mobile technology cannot reach the hundreds of millions of people ready to embrace it. 3.1 The Obstacles

Rural India has a massive pent-up demand for mobile services; a limitless supply of low-cost labour to help deploy them; and a large entrepreneurial class ready to deliver services at the local level. Cheap handsets are available and, unlike urban locations, space for Base Stations is plentiful. As powerful as these market drivers may be, the inhibitors are even more formidable. The obstacles to providing profitable mobile services to rural India (and similar rural populations all over the world) come from two main sources: the inherent constraints of the market – its geography, economy and skill levels; and the inherent limitations of current GSM technology, processes and models. The Challenges of Rural India: There are four main difficulties in serving rural communities, each one of which has appeared insurmountable: Power challenges – Most of rural India is not served by the power grid. Some areas may get ‗agricultural power‘ – two hours in the morning and evening – but even this is the exception. When fuel can be afforded and delivered, power tends to come from diesel generators. The combination of poor fuel quality and poor generator maintenance severely limits the life of any generator. Revenue challenges – Rural India can pay for mobile services, but only around $2 per month. The cost base of any solution has to be geared to these ARPU levels. Skills challenges – There are no trained telecom engineers and few people can read or write. This makes the installation and maintenance of GSM networks highly challenging. Access challenges – These are extremely remote communities, served by poor roads and no other significant infrastructure. Despite these challenges, other complex services have profitably been delivered to rural India (including cable television). Unfortunately, the mobile systems in use all over the world today seem to have been designed to maximize vulnerability to these four challenges. Today’s GSM is not ready to serve rural India.

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4.0 The limits of Traditional GSM

GSM was designed for urban and suburban locations in developed markets. It‘s a general-purpose network not suited to the unique challenges of serving rural and remote areas. The gulf between GSM challenges and the opportunities in the rural sector is quite wide. There are certain demands of traditional GSM which the rural sector cannot fulfill. These are listed below; Deployment demands – The typical GSM Base Station includes three refrigerator-sized cabinets, mains power supply, large battery backup, dual air conditioning units, a tower or roof site and backhaul capability. All this is housed in some kind of building – either existing or built for purpose. Just getting all of this equipment to a rural community multiplies the cost of deployment – before provisioning, civil engineering, radio planning, testing and maintenance is factored in. Power demands – Power was clearly not an issue when GSM was conceived. A conventional Base Station site alone requires about 5000W to run – not including any Base Station Controller (BSC) or Mobile Switching Center (MSC). Due to power availability constraints even in urban settings, the current GSM networks in India are estimated to burn about 2 billion litres of diesel each year. Fuel quality, transport challenges and the demands of generator maintenance make this power source unsustainable for rural GSM deployments. Skills demands – A typical GSM Base Station deployment process takes around three months from planning to commissioning, and involves dozens of people including radio network planners, site acquisition teams, site engineers, civil engineers, equipment vendor installation professionals and commissioning teams from the operator. This supply chain can barely meet the demands of the urban mobile infrastructure. It could never scale for the rural opportunity even if it could do so cost-effectively (a clear impossibility). The workforce in rural India has none of the skills necessary to deploy and maintain today‘s GSM. Cost demands – A typical GSM Base Station alone costs in the region of $100,000, before BSC and MSC costs are factored in. Funding this capital expenditure requires the kinds of population densities and ARPU levels found only in urban areas. Rural communities simply do not justify the cost of today‘s GSM infrastructure – and no government subsidy can fill the gap. Taken together, the challenges inherent to the rural opportunity and the limitations and demands of traditional GSM create a circle that is impossible to square. Asking traditional GSM to serve the population of rural India is like getting an elephant through the eye of a needle. We need to take another approach.

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So due all these constraints, the industry today is in dilemma about how to provide services to those in need and earn revenue at the same time. One way companies are doing this is by reducing their cost instead of charging high to the customers. This project report deals with TTSL (Tata Teleservices Limited) project which is implementing a new solution which would lower the cost of transmission of voice & data from village BTSs to faraway BSCs. This would reduce the capex & opex of the company and it would thus enable the company to provide services in the rural sector at a lesser rate thus earning revenue at the same time and doing corporate social responsibility on the other.

5.0 About TTSL

Tata Teleservices is part of the INR Rs. 2,51,543 Crore Tata Group that has over 80 companies, over 3, 30,000 employees and more than 3.2 million shareholders. With a committed investment of INR 36,000 Crore (US$ 7.5 billion) in Telecom (FY 2006), the Group has a formidable presence across the telecom value chain. Tata Teleservices spearheads the Group‘s presence in the telecom sector. Incorporated in 1996, Tata Teleservices was the first to launch CDMA mobile services in India with the Andhra Pradesh circle. Beginning with its acquisition of Hughes Telecom (India) Limited in December 2002 [now renamed Tata Teleservices (Maharashtra) Limited], which provides services in the Mumbai and Rest of Maharashtra telecom circles, the company has swung into expansion mode and currently has a pan-India state-of-the-art network. Having pioneered the CDMA 2000 technology platform in India, Tata Teleservices has established a 3G-ready robust and reliable telecom infrastructure in partnership with Motorola, Ericsson and Lucent. The company has also received the license from the Department of Telecommunications to launch GSM services as well. With this launch set for early 2009, TTSL is on the threshold of emerging as a true-play dual technology telecom operator. In November 2008, Tata Teleservices entered into an agreement with Japanese telecom major NTT DOCOMO, as part of which the Japanese company acquired a 26% stake in TTSL for USD 2.7 billion. The transaction marks a key step in the strategic evolution of Tata Teleservices, as it moves towards a pan-India dual network presence. On a broader level, the transaction is also expected to mark the beginning of a relationship of broader co-operation between Tata companies and the Nippon Telegraph and Telephone Corporation (NTT).

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The potential benefits and synergies from the alliance with DOCOMO cut across marketing, handset development and technical support, all of which are expected to create new opportunities for both companies. The alliance will also accelerate Tata Teleservices‘ GSM plans and help the company penetrate the market with advanced technology and new VAS offerings. Tata Teleservices‘ bouquet of telephony services includes mobile services, wireless desktop phones, public booth telephony and wireline services. Other services include value-added services such as voice portal, roaming, post-paid Internet services, 3-way conferencing, group calling, Wi-Fi Internet, USB Modem, data cards, calling card services and enterprise services. Some of the other products launched by the company include prepaid wireless desktop phones, public phone booths, new mobile handsets and new voice and data services such as BREW games, voice portal, picture messaging, facebook, M commerce applications, polyphonic ring tones, interactive applications like news, cricket, astrology, etc 5.1 TTSL in rural domain According to a news article in Hindustan Times:

TTSL to invest Rs 1K cr in rural expansion

Tata Teleservices Ltd (TTSL) plans to invest about Rs 1,000 Crore for its rural thrust that will include setting up of specialized 3,000 base stations in difficult terrains in rural parts of the country. The company has plans to launch a sub Rs 1,500 mobile handset models for the rural market. The roll out of the base station would be enhanced particularly in Uttar Pradesh, Bihar, Orissa and West Bengal. TTSL is confident that it would be able to ride on the code division multiple access (CDMA) technology to offer not only voice data services but also other such high-end services to its customers.

Speaking to Hindustan Times, Darryl Green, chief executive officer (CEO) TTSL said, "A large part of India still does not have network coverage and our endeavor is to provide connection to those remote parts of the country." While, the company plans to expand its reach in rural areas, it also plans to introduce new high-end products during the year, which will be targeted at enterprise and small and medium enterprises (SMEs) segments.

"The aim is to provide enterprise and SMEs the technology advantage using the CDMA platform. We would like to offer the latest products available in CDMA to enhance the productivity of these segments," said Green. Refusing to discuss the subscriber linked allocation of spectrum Green said, that there is a need for introspection on part of the policy makers, as to why operators would make investments in technology that would yield low performance, when enhanced technologies are available in the country.

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So this shows that TTSL is keen to expand its network in the rural sector. This report deals with the solution Alcatel-Lucent has provided to TTSL along with a 3rd party, company called Cell&Sat. It is called BSS Local Switching which is discussed in the subsequent sections of this report.

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BSS Local Switching UNIT 2

Chapter 2

1.0 Introduction

GSM is growing rapidly worldwide. As the number of GSM users continues to increase steadily and competition grows fiercer, most operators are spending much more time and money trying to expand their network capacity. Meantime however, most newly-added GSM users are low-end users (as discussed in the previous chapter that urban teledensity has reached about 86% so now rural market is being targeted), which results in a steadily decreasing ARPU. In order to increase revenues, operators are eagerly seeking effective ways to reduce TCO (Total Cost of Ownership) while at the same time ensuring service quality. As GSM penetration has almost reached the saturation point in most developed areas, GSM is now expanding in less developed areas (emerging markets). In these areas, the telecom infrastructure is extremely underdeveloped and transmission equipment required for deploying a mobile network constitutes a very large investment, thus transmission becomes a big challenge. With backhaul still one of the most formidable barriers faced by telcos in emerging markets wanting to extend coverage to rural villages, satellite has been touted for some time as the most efficient way to connect remote base stations to the PSTN. One problem: space segment links are costly, and even with costs coming down in certain regions, a 2-Mbps satellite link still costs as much as $10,000 a month. So, a new solution “BSS Local Switching” is employed to overcome these problems and help telcos to expand and earn.

2.0 Transmission costs

Operators have noticed that, in a TCO model of the emerging market, the transmission cost represents a large portion of the total costs, and therefore, any savings that can be made in terms of the transmission cost is also a key to lowering the TCO of the mobile network. In general, an average of 30% of all the calls processed by a base station controller (BSC) is local calls. Billing analysis of China Mobile shows that the number of local calls amounts to about 50% in some areas. The number is even higher in Latin American and in some African countries. For example, billing analysis of an operator in Colombia shows that BSC local calls accounts for about 60% of all calls made.

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Moreover, in some densely populated areas and in a few remote areas, most calls (both for calling parties and the parties being called) are processed by an independent BSC, or by a group of BTSs. According to present GSM protocol, all calls must be switched by MSC, even when two parties are talking face to face. Thus operators have to pay expensive toll call transmission fees for local calls. This transmission fees for toll call can be reduced by employing BSS Local Switching.

3.0 Traditional Solution

The traditional solution for GSM Abis backhaul by satellite is shown below:

Figure 48. Traditional GSM solution

The traditional solution is to provide dedicated satellite resources: • E1 (or T1) circuit interface • Most utilized solutions are with (costly) ―IBS-IDR‖ modems • Permanent resources are reserved on satellite: even for low traffic BTS! • Possible capacity savings with ―Abis compressors‖ for silence removals • Overall: OPEX about 1350 $ per BTS (1TRX) per month

4.0 Broadband IP Satellite GSM Backhaul

New solution is to utilize broadband IP satellite solutions to backhaul GSM Abis: • Low cost satellite terminals • E1 / IP multiplexers • Compression / silence removal Low cost solution for low traffic BTS: • About 300$ per Erlang per month (Full Rate) • Half Rate reduces by factor 2

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4.1 Broadband IP satellite GSM backhaul

Figure 49. Existing IP based solution

4.2 Cell&Sat Proposal-benefit from low cost broadband IP satellite + optimize for GSM Abis transport:

Figure 50. Broadband IP satellite backhaul + optimization

Cell&Sat cost optimization: Benefits of IP broadband: One central hub serves many low-cost Sat+BTS in Villages Cost is only proportional to actual traffic: ideal for low traffic areas

Dedicated equipment to improve quality & reduce cost: «CST / CSG» provides E1 / IP translation + compression «CSO» analyses signalling on interface, «CSM» provides central

management

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Satellite resource allocation is optimized for GSM traffic backhaul Local mobile to mobile calls do not use any satellite resources (no double

hop) Adaptable to any satellite solution and GSM network: Cell & Sat optimizers are transparent to GSM equipment Cell & Sat optimizers are adaptable to all satellite network solutions

Ideal solution for low cost GSM in remote villages: 200$ per Erlang per month (Full Rate),i.e. < 2 cents per minute inter-

villages Local calls for free intra-village

Cell&Sat Traffic Optimization & QoS monitoring: CST/ CSG /CSO measure the quality provided by the Satellite + IP link: Every BTS is equipped with low-cost CST collecting traffic and QoS

statistics CSG and CSO also collecting data at Hub and BSC locations

CSM is the central Operation and Maintenance platform: Collecting all performance data and verifying SLA commitments

– Can also be linked to Satellite Hub NOC – Can interface with GSM operator Operation & Maintenance Centre Providing high level Operator interface for IP Satellite backhaul

configuration – Defining detail parameters for traffic / cost optimization Reporting alarms:

– Faulty equipments, congestion, end-to-end performance degradation CSO implements traffic optimization functions based on detailed GSM and satellite information: Patented algorithms based on GSM signalling message analysis More than just IP backhaul: optimized broadband satellite backhaul!

5.0 Operational Scenarios

Step 1: introduce IP transport – CST & CSG multiplexers Step 2: provide optimisation and high level monitoring functions – CS0 and CSM introduction The architecture is shown in the following diagrams in 2 steps:

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Figure 51. Introduction of IP backhaul

Figure 52. Cell&Sat Optimization

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5.1 Several options for Cell & Sat in the value chain Customer is cellular operator

Partner is satellite solution provider

Cell & Sat defines the IP satellite backhaul solution adapted to GSM operator requirements

Operational options:

1) The cellular operator remains in charge of transmission operation interfacing directly with Satellite operator Cell & Sat can provide QoS SLA monitoring & optimisation services

2) Cell & Sat + Satellite partner operate Abis link: charged per Erlang per month

3) Cell & Sat + partners becoming « Village roaming operator »: GSM voice calls charged per minute

6.0 Other Options:

Figure 53. Full BSC option

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Figure 54. Roaming Operator Option

7.0 Cost Savings by Creative Solutions

Integrated BSC solution: The integrated BSC solution introduced by Alcatel-Lucent adopts some of the advantages associated with a highly integrated BSC, wireless media gateway (WMG) and Transcoder (TC). In the solution, the BSC, WMG, and TC are built into one cabinet. This solution primarily applies to a local area where the number of subscribers is less than 100,000 and there is a high local call ratio. The integrated BSC solution should meet the following conditions: The core network uses a mobile softswitch; the BSS and NSS in the entire network are provided by the same vendor. If the preceding two conditions are met, then the solution may help operators save about 60% in their transmission cost, and another 50% in equipment space.

BSS Local Switching: The BSS local switching can be free from the core network. If the calls for calling parties and called parties belong to the same BSC/BTS, then the BSC will conduct local switching for the services. In the BSS local switching, the BSC directly switches the subscriber data. Alcatel-Lucent‘s BSS local switching is also transparent in relation to the core network (CN), so it doesn‘t require any modification of the core network. In a normal GSM network, when BSC forwards calls to CN for the switching, all the voice calls should go through the TC, because the coding system used by GSM BSS and CN are different. Moreover, before voice calls reach the CN, TC needs to encode or

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decode the voice calls. In the BSS local switching, however, there is no need to encode or decode the voice calls, because the local call data is switched directly on local. Hence, Alcatel-Lucent‘s BSS local switching solution is able to enhance the voice quality. Alcatel-Lucent‘s BSS local switching can reduce the transmission cost between the BSS and CN. Under special circumstances such as, at a grand ceremony of some kind, or in the case of a temporarily-expanded site, BSS local switching can help to provide temporary coverage or emergency communications, which will eventually reduce the use of transmission resources. BTS group and BTS Local Switching In the current GSM network, all the BTSs are connected to the BSC. If each BTS uses an independent link to connect to the BSC, then transmission efficiency is usually quite low, which is usually the case with a microwave or satellite network. In this instance, the HUB BTS solution will be able to help operators to overcome this problem. In HUB BTS networking, several neighboring BTSs are connected to a HUB BTS, as the distance is shorter when comparing it to the connection to the BSC. Then the HUB BTS is connected to the BSC. This in turn will decrease the number of transmission links needed to connect each BTS to a BSC, and thus, will lead to a reduction of more than 20% in the transmission resource on Ater and Abis interfaces. BTS group can also be used to achieve local switching. The BTS group switches the voice traffic of the calls that are initiated between the BTS and the HUB BTS. In areas where there is insufficient transmission equipment such as, in a desert, on isolated islands, in mining districts, or in oil fields, it is ideal for the implementation of BTS local switching or the HUB BTS.

So using BSS Local Switching the telcos can reduce their cost and thus can provide cost effective services to the rural population while earning revenue at the same time.

Now in the subsequent sections we will discuss about adding this feature in the already existing hardware- Spatial Atrium and how it will actually work.

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SDLC UNIT 2

Chapter 3

1.0 Introduction

Now in the previous chapter we have studied about the benefits of installing Cell&Sat proposal. In this chapter we will see how to implement this new feature in the already existing Alcatel-Lucent network hardware setup used by TTSL. TTSL is currently employing the Spatial Atrium 5020 of Alcatel-Lucent and wants to start BSS Local Switching feature in its network. As such no changes will be made in the hardware part (except from installing new Cell&Sat equipments) but changes in the operating system of the hardware (which is a software) will be made. MSC of Alcatel-Lucent should be able to recognize the Cell&Sat equipments and should be able to work in synchronization with them. This chapter will deal in implementing this new solution in the hardware part by making changes in the software part. We will study SDLC (Software development Lifecycle) and see how the process of implementing a new feature is carried out.

2.0 Software Development Life Cycle (SDLC)

A software lifecycle model is a descriptive and diagrammatic representation of the software lifecycle. A lifecycle model represents all the activities required to make a software product transit through its lifecycle phases. It also captures the order in which these activities are to be undertaken. In other words a lifecycle model maps the different activities performed on a software produced from its inception to retirement. The first stage in the lifecycle of any software product is usually the Feasibility study stage. Commonly, the subsequent stages are: Requirement analysis and specification, Design, Coding, Testing and Maintenance These stages are defined step by step in the subsequent parts of this chapter.

3.0 Feasibility Study

The main aim of the feasibility study activity is to determine whether it would be financially and technically feasible to develop the product. It involves the

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analysis of the problem and collection of all relevant information relating to the product such as the different data items which would be input to the system, the processing required to be carried on these data, the output data required to be produced by the system, as well as the various constraints on the behaviour of the system. The collected data are analyzed to arrive at the following:

An abstract problem definition considering only the important requirements and ignoring the rest.

Formulation of different solution strategies. Analysis of alternative solution strategies to compare their benefits

and shortcomings. This analysis requires estimates of the resources required, cost of development, and development time for each of the options. These estimates are used as the basis for comparing the different solutions.

Once the best solution is identified, all later phases of development are carried out as per this solution. Thus, during the feasibility study, most of the high-level architectural designs are made. Therefore, feasibility study is considered to be a very important stage. During this study, it may come to light that none of the solutions is feasible due to high cost, resource constraints, or some technical reasons. This scenario would of course lead to the project been abandoned.

4.0 Requirement Analysis and Specification

The aim of the requirement analysis and specification phase is to understand the exact requirements of the customer and to document them properly. This phase consists of two distinct activities, namely requirements gathering and analysis and requirement specification. Requirement gathering and analysis The goal of this activity is to collect all relevant information from the customer regarding the product to be developed with a clear understanding of the customer requirements and removing incompleteness and inconsistencies in these requirement. The activity begins by collecting all relevant data regarding the product to be developed from the users of the product and from the customer through interviews and discussions. After all ambiguities, inconsistencies, and incompleteness (depending upon the personal views of the respondents) have been resolved and all the requirements properly understood, the requirements specification activity can start. During this activity the user requirements are systematically organized into a Requirement Description Sheet. Requirement specification The customer requirements identified during the requirement gathering and analysis activity are organized into a RDS document. The important components of this document are the functional requirements, the

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nonfunctional requirements and the goals of implementation. The RDS document is written using the end-user terminology. This makes the RDS document understandable by the customer. It serves as a contract between the development team and the customer. The RDS document produced at the end of this phase is called the ―black-box‖ specification of the problem. In other words, the requirement analysis and specification phase concentrates on what needs to be done and carefully avoids the solution (how to do) aspects.

5.0 Design

The goal of the design phase is to transform the requirements specified in the RDS document into a structure that is suitable for implementation in some programming language. Or we can say that during this phase the software architecture is derived from the RDS document. 2 different design approaches are available: the traditional design approach and the object-oriented design approach. Traditional design approach Traditional design consists of two different activities; first a structured analysis of the requirement specification is carried out where the detailed structure of the problem is examined. This is followed by a structured design activity. During structured design, the result of the structured analysis is transformed into the software design. Structured analysis involves preparing a detailed analysis of the different functions to be supported by the system and identification of the data flow among the different functions. Each function required by the customer is studied carefully and is decomposed into various subfunctions. Data flows among the processes or the functions are identified. Data flow diagrams are used to perform the structured analysis and to document the results. Structured design is undertaken once the structured analysis activity is complete. Structured design consists of the 2 main activities: architectural design (also called high-level design) and detailed design (also called low-level design). High level design involves decomposing the system into modules and representing the interfaces and the invocation relationships among the modules. A high level software design is sometimes referred to as software architecture. During detailed design, internals of the individual modules are designed in greater details e.g. the data structures and algorithms of the modules are designed and documented. Object-oriented design approach Object-oriented design (OOD) is a relatively new technique. In this technique, various objects that occur in the problem domain and the solution domain are

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first identified and the different relationships that exist among these objects are identified. The object structure is further refined to obtain the detailed design. The OOD approach has several benefits such as lower development time and effort, and better maintainability of the product.

6.0 Coding and Unit Testing

Testing a program consists of subjecting the program to a set of test inputs (or test cases) and observing if the program behaves as expected. The purpose of the coding and unit testing phase is to translate the software design into source code. It is sometimes called implementation phase. Each component of the design is implemented as a program module. The end-product of this phase is a set of program modules that have been individually tested. During this phase each module is unit tested to determine the correct working of all the individual modules. It involves testing each module in isolation as this is the most efficient way to debug the errors identified at this stage. Another reason behind testing a module in isolation is that the other modules, with which this module has to be interfaced, may not be ready. Unit testing also involves a precise definition of the test cases, testing criteria, and management of test cases.

7.0 Integration and System Testing

Integration of different modules is undertaken once they have been coded and unit tested. During the integration and system testing phase, the modules are integrated in a planned manner. The different modules making up a software product are almost never integrated in one shot. Integration is normally carried out incrementally over a number of steps. During each integration step, the partially integrated system is tested and a set of previously planned modules are added to it. Finally, when all the modules have been successfully integrated and tested, system testing is carried out. The goal of system testing is to ensure that the developed system conforms to its requirements laid out in the RDS document. System testing usually consists of three different kinds of testing activities.

α- testing: It is the system testing performed by the development team;

β- testing: It is the system testing performed by a friendly set of customers.

acceptance testing: It is the system testing performed by the customer himself after the product delivery to determine whether to accept or reject the delivered testing.

System testing is normally carried out in a planned manner according to the system test plan document. The system test plan identifies all the testing-related activities that must be performed, specifies the schedule of testing, and allocates resources. It also lists all the test cases and the expected outputs for

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each test case. Immediately after the requirements specification phase, a system test plan can be prepared which documents the plan for system testing. It is possible to prepare the system test plan just after the requirements specification phase, solely based on the RDS document. The results of integration and system testing are documented in the form of a test-report. The test report summarizes the outcome of all the testing activities hat were carried out during this phase.

8.0 Maintenance

Maintenance of a typical software product requires much more effort than the effort necessary to develop to develop the product itself. Many studies carried out in the past confirm this and indicate that the relative effort of development of a typical software product to its maintenance is roughly in the 40:60 ratio. Maintenance involves performing any one or more of the following three kinds of activities:

Correcting errors that were not discovered during the product development phase that is called corrective maintenance.

Improving the implementation of the system, and enhancing the functionalities of the system according to the customer‘s requirements which is called perfective maintenance.

Porting the software to work in a new environment is called adaptive maintenance.

However, in the practical development environments, the engineers commit a large number of errors in almost every phase of the life cycle. The source of the defects can be many: oversight, wrong assumptions, use of inappropriate technology, communication gap among he project engineers, etc. These defects usually get detected much later in the life cycle. For example, a design defect might go unnoticed till the coding or testing phase. Once a defect is detected, the engineers need to go back to the phase where the defect had occurred and redo some of the work done during that phase and the subsequent phases to correct the defect and its effect on the later phases. So, feedback paths are present in this model from every phase to its preceding phases as shown in figure below to allow for the correction of the errors committed during a phase that are detected in later phases. Though errors are inevitable in almost every phase of development, it is desirable to detect these errors in the same phase in which they occur. Figure below shows the process how the process actually works:

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Feasibility Study Requirement analysis and specification Design Coding and Unit testing Integration and System testing Maintenance

Figure 55. Software Development Life Cycle (SDLC) at Alcatel-Lucent

The errors should be detected as early as possible. For example, if a design problem is detected in the design phase itself then this problem can be taken care of much more easily than if it is detected at the end of the integration and system testing phase. In the later case, it would be necessary not only to rework the design, but also to appropriately redo the coding and the system testing, thus incurring higher cost. The principle of detecting errors as close to their points of introduction as possible is known as phase containment of errors. This is an important software engineering principle. The later chapters of this report will deal with the RDS, HLD, Test plan, etc. required for BSS Local Switching.

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RDS for BSS Local Switching UNIT 2

Chapter 4

Introduction

Now that the software development part has been discussed, in this chapter we will study the first part of the software development i.e. Requirement Description Sheet (RDS). RDS deals with all the requirements of the client and the description about how the requirements would be fulfilled. Given below is the RDS of BSS Local Switching. Till now we have discussed about the current product of Alcatel-Lucent i.e. Spatial Atrium 5020 being employed by TTSL. To overcome the cost barriers which are preventing TTSL to provide transmission in rural areas (cost of transmission cannot be high as the ARPU in the rural areas is quite low), a new solution is being deployed by setting up 3rd party‘s product i.e. Cell&Sat. Cell&Sat products will be deployed along with the Spatial Atrium to lower the cost of transmission. Now as Spatial Atrium is already with TTSL so it wants some changes in the working of Spatial Atrium so that along with the Cell&Sat products, it can enable the BSS Local Switching. The changes will be made in the software which will be shown in the next releases as required by the company. So RDS document is made from the side of Alcatel-Lucent to clearly understand the needs of TTSL and also to show how the solution will be finally implemented. RDS is finalized after a long series of discussion with the TTSL employees. After it is approved by TTSL, work on the designing and coding part will start (as shown in the chapter titled SDCL). This report deals with the implementation phase as it was the part of the project in developing test plan and understanding various phases of the software development life cycle.

*** The documents viz. RDS, HLD, Test Plan etc. are strictly the property of Alcatel-Lucent. No part of these documents may be photocopied, reproduced, or translated to another language without prior written consent of Alcatel-Lucent. The information contained herein has been prepared by Alcatel-Lucent, its employees, agents and customers. Dissemination of the information and/or concepts contained herein to other parties is prohibited without the prior written consent of Alcatel-Lucent.

Attached now is the official RDS of the BSS Local Switching.

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HLD for BSS Local Switching UNIT 2

Chapter 5

1.0 Introduction

The purpose of this document is to describe the high level design of the software modules required to implement feature F3212 RDS11765 <BSS Local Switching>. The document will be used as reference and guideline for implementation and testing.

SCOPE

This feature is applicable to A5060 Wireless Call Server (WCS). This feature will be implemented in Release R5.0. The Implementation of this feature is limited to GSM and A over TDM transport. This implementation of this feature is limited to ALU BSS and 3rd party (Cell&Sat) products.

1.1 Assumptions

Exception and Incompliance

In ETC scenarios to an SRF, the WCS will send a CONNECT message

to the calling party before the called party picks up the call if the WCS is requested to set up a both-way through connection between the UE & the SRF. In this case, the WCS will not be able to relay any User-User IE that may be received afterwards from the called party. This should remain very rare scenarios.

Support of local switching in MSC pool configuration will require, in

addition, to send the User-User signaling through ISUP, BICC, SIP-I (and possibly even in SIP if used to interconnect MSC-S). This will not be supported, as MSC pooling is not deployed yet.

Hardware and Software Constraints

Solution restricted to ALU BSS and 3rd party (Cell&Sat) Products For CSD calls the BSS Local switching functionality is not supported. The BSS does not apply local switching if different speech codecs are

used at calling/called accesses. RELEASE AVAILABILITY

In the deliverables for Release 5.0 of WCS include support of ―BSS Local Switching‖ with ALU BSS & 3rd Party (Cell&Sat) Products. Requirements Traceability

This section maps each requirement to sections within this document that realize the requirement. Use cross-references for easy updating.

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Requirement Description Section(s)

RDS11765: R001 User-User signaling support 0,0

RDS11765: R002 Interaction with Call Forwarding 0,0

RDS11765: R003 'BSS local switching' option 0,0

RDS11765: R004 Protocol Discriminator of BSS inserted User-User IE 0,0

REFERENCES

External Reference

3GPP TS 23.002 Network Architecture 3GPP TS 23.018 Basic Call Handling 3GPP TS 24.008 Mobile radio interface layer 3 specification; Core

Network Protocols-Stage 3 http://www.cell-sat.com/ http://3gsm.converve.com/p_cat_par_3gsm.php?page=3&detail=320

Internal references

RDS 11765 v3.2 BSS Local Switching

ACRONYMS

BTS Base Transceiver Station BSC Base Station Controller CST Cell & Sat Terminal CSO Cell & Sat Optimiser CSG Cell & Sat Gateway CSM Cell & Sat Manager IDU Indoor Unit ODU Outdoor Unit WCS Wireless Call Server WSS Wireless Softswitch

2.0 FEATURE DESCRIPTION

2.1 FEATURE OVERVIEW Figure below shows how this feature will be implemented. It shows the place where Cell&Sat equipments will be required to provide this service.

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Figure 56. BSS System Level View

The current Atrium WSS does not support User-User Signaling IE inserted by UE/BSS. If the feature ―BSS Local Switching‖ is enabled by the operator the WCS will be able to support for User-User Signaling IE in the connect message inserted by BSS. The WCS will support a User-User IE received in the CONNECT message from the called mobile, and it will be forwarded in the CONNECT message to the calling mobile to trigger local switching in BSS when the BSC <-> BTS links (Abis1) are carried through satellite.

The implementation of this feature is to Support local call switching in BSS for OPEX saving (to save transmission costs) in network configurations where the BSC <-> BTS links (Abis) are carried through satellite. In addition, local switching may also allow improving the speech call quality and provide Cost effective solution for rural GSM.

1 When the BSS consists of a Base Station Controller (BSC) and one or more Base Transceiver Stations

(BTS), this (Abis) interface is used between the BSC and BTS to support the services offered to the GSM users and subscribers. The interface also allows control of the radio equipment and radio frequency allocation in the BTS.

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Figure 57. Interfaces between BTS & BSC

The Solution is based on ALU BSS and 3rd party (Cell&Sat) products (CST, CSO, CSG) connected on the Abis interface to the BTS and BSC, requiring the MSC-S to support relaying of User to User signaling IE to trigger local switching.

In each CONNECT message from the called mobile (speech calls only), the BSS (CSO) inserts a User-User IE including certain identifiers and time-stamp. The BSS (CSO) also analyses each downlink CONNECT message to calling mobiles (speech calls only). If a User-User IE is found in a downlink CONNECT message, with same value as previously inserted in a previous uplink CONNECT, both CONNECT messages are assumed to pertain to the same call and the BSS is able to locally switch the user plane of that call. To Support the above mechanism, the WSS (MSC-S) needs to support relaying the User-User Signaling IE.

2.2 Scenarios and Message flows

Mobile-to-Mobile calls. Supplementary services – Call Forward, Call wait, Call Hold, ECT CAMEL

2.3 External Protocols and Messages The DTAP message connect is modified, the User-User IE is inserted in the DTAP connect message by BSS.

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2.4 User Feature Interactions N/A. 2.5 System FEATURE Interworking

System Features Impacted (Y)

CALEA Y

CAMEL Y

SS Y

2.5.1 Call Forwards User-User IE is received in the CONNECT message from the called party. So the interaction with Call Forward is the receipt of a User-User IE from a forwarded-to party and its transmission to the calling party, in the same conditions as those specified 0 2.5.2 Camel interactions The requirement to forward the User-User IE will be supported even with CAMEL interactions. 2.5.3 ECT The interaction with ECT is the receipt of a User-User IE from a transferred party and its transmission to the calling party, in the same conditions as those specified 0 2.5.4 Calea

The WCS upon receipt of User-User IE in connect message will check if the call is intercepted if yes then WCS will increment the four-bit mode field of the User-User information field. The four-bit mode field will be treated as a binary encoded integer in the range 0 to 15, and will be incremented by 1 modulo 16 (when to be incremented). Bits 5 to 8 of octet 4 and octets 5 to N will be transmitted unmodified by the WCS.

Note :-If both subscribers are LEA subjects the four-bit mode field will be incremented twice. 2.5.5 Interaction with 2nd call and with Call Waiting In "Call Hold + new call" (A calls B, A puts B on hold, A calls C) and Call Waiting scenario (A and B in a call, C calls A), the User-User IE will be transferred in CONNECT between A & C, in the same conditions as those specified in 0 2.5.6 Billing N/A

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2.6 Access Technology impacts Solution limited to GSM and A over TDM transport. 2.7 MGCF IMPACTS N/A

3.0 System Level Design

3.1 Software Architecture 3.1.1 BSS Local Switching option The WCS will support a WCS-wide parameter allowing the operator to enable or disable this feature. When disabled, the WCS behaves as per existing implementation (no User-User IE transferred). Default value for this parameter will be: 'disabled'. 3.1.2 Protocol discriminator of U-U IE inserted by BSS The WCS will support receipt of the User-User IE in the CONNECT message received from the called party if the BSS Local switching option is enabled. The WCS will be able to identify whether the User-User IE received in the CONNECT message was inserted by BSS or sent by UE based on the protocol discriminator field configured in the WCS. The WCS will support a WCS-wide parameter (‗BSS UU PD‘) allowing the operator to configure the Protocol Discriminator of User-User IE inserted by the BSS. Range: 0 to 255 Default value: 16 (i.e. PD '00010000') If the User-User IE is sent by UE it will be ignored and not relayed, as per existing WCS implementation. 3.1.3 Mechanism for BSS Local Switching

The BSS will monitor the signalling messages on the Abis interface, if the BSS detects of time correlation between SETUP and PAGING RESPONSE messages in the local switching area it then inserts User-User IE into the subsequent uplink CONNECT message (from the called mobile).

The WCS on receipt of the Connect message from the called mobile with User-User IE inserted in it by BSS will check if WCS wide office parameter BSS local Switching is enabled - a) If the value of the feature parameter is disabled then WCS will ignore

the User-User IE and the existing WCS behavior will be applicable.

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b) If the value of the WCS-wide office parameter is enabled then WCS will obtain the value of Protocol discriminator field from database and check-

The User-User IE is inserted by BSS & If the call is local to the WCS If the above conditions are met WCS will check if the call is intercepted

if yes then WCS will increment the four-bit mode field of the User-User information field.

The WCS will then relay/forward this User-User Signalling IE in the connect message to the calling mobile.

The four-bit mode field of User-User IE will be incremented twice if both subscribers are Lea subjects.

If BSS finds a User-User IE in a downlink CONNECT message, with same value as previously inserted in a previous uplink CONNECT, then both CONNECT messages are assumed to pertain to the same call and the BSS is able to locally switch the user plane of that call. Intercepted calls will not be locally switched or will be switched with a half-loop

3.1.4 User-User Signaling IE

The purpose of the user-user information element is to convey information between the mobile station and the remote ISDN user. There are no restrictions on the content of the user-user information field.

8 7 6 5 4 3 2 1

User-user IEI octet 1

Length of user-user contents

octet 2

User-user protocol discriminator

octet 3

Four-bit mode field octet 4* User-user information octet N*

Figure 58. User-User Signaling IE format

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Figure 59 User-User IE Octet 3 bits

The user-user is a type 4 information element with a minimum length of 3 octets and a maximum length of either 35 or 131 octets. In the SETUP message the user-user information element has a maximum size of 35 octets in a GSM PLMN. In the USER INFORMATION, ALERTING, CONNECT, DISCONNECT, PROGRESS, RELEASE and RELEASE COMPLETE messages the user-user information element has a maximum size of 131 octets in a GSM PLMN. In other networks than GSM PLMNs the maximum size of the user-user information element is 35 or 131 octets in the messages mentioned above. The evolution to a single maximum value is the long-term objective; the exact maximum value is the subject of further study. NOTE: The user-user information element is transported transparently through a GSM PLMN.

3.2 Inter-process messages

No new inter-process messages are added. . 3.3 Impacted Subsystems/areas

BSS and NSS subsystems impacted.

4.0 Process Level Design

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Processes Impacted (Y)

Application CpCallm Y EMS Y

Database Y

4.1 Impacted common areas None 4.2 Impacted processes 4.2.1 CpCallm Following changes will be done in internal signals

S.No. Signal Change

1. Mate_connect To transfer the user-user IE in basic call user-user IE will be sent in this signal

2 Ccp_ss_request To transfer the user-user IE from one trio to another in case of SS user-user IE information will be sent in this request from Ohcp to ccp

3 ccp_ss_notification User-User IE will be sent in ccp_ss_notification signal to ohcp/Thcp

Following flowchart explains the logic for transferring User-User IE in CONNECT message from called to calling party at CpCallm end.

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Figure 1 Logic for transferring User-User IE in CONNECT message

Existing implementation will be applicable

Start

Check if BSS local Switching feature option is enabled?

Increment the four-bit mode field of U-U IE

Check if the called party subscriber is a LEA subject?

Send the User-User IE in Connect message to calling party BSS

THCP receives UU IE in the connect message of called party

Obtain the value of Protocol Discriminator (PD) field of U-U IE from database

Compare PD value = WCS-

wide BSS UU PD

Relay the U-U IE to OHCP

Check if the calling party subscriber is a LEA subject?

Increment the four-bit mode field of U-U IE

Stop

No

No

Yes

Yes

No

Yes

No Yes

4.2.1.1 Changes for SS and Camel scenario

Call Forward

Figure 60 Transfer of U-U IE incase of Call Forward Scenario

Note: - The above call flow is also applicable for Camel scenario. For both Scenarios (Call forward & Camel) the U-U IE needs to be transferred from one trio to another. 4.2.2 EMS

4.2.2.1 New parameters [BSS Local Switching & BSS UU PD]

Two new system level configurable parameters are introduced for this feature

1. BSS Local Switching

2. BSS UU PD

These two parameters are added in the WCS wide parameter group of Call Manager Tab. Below diagram is to select the above two option

Spatial Atrium | | + System Parameters [Tree List] | | + Call Manager [Tab Button] | |

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+ WCS wide parameter [Group Box] | |

+a) BSS Local Switching +b) BSS UU PD

The first parameter ‗BSS Local Switching‘ will be configurable by selecting enable /disable from a drop down list. The default value of this parameter will be disable.

The second parameter ‗BSS UU PD‘ will be configurable by setting any number between 0 to 255.This parameter is dependent on ‗BSS Local Switching‘, means if BSS Local Switching‘ is in disable mode user will not able to edit the value of BSS UU PD parameter, and in enable condition user can assign a value to ‗BSS UU PD‘ in range [0-255]. Default value of this parameter will be 16.

Dynamic update is required for this parameter.

4.2.2.2 Database Changes

Following new System Level Configuration Parameter need to be added in SYS Database table: SPATIAL.CONFIGPARAMS

Field Description for BSS Local Switching

Table: SPATIAL.CONFIGPARAMS

Field Name Type Value

*NODENAME CHAR (15) NOT NULL CPSNodes

*SUBSYSTEMNAME CHAR (31) NOT NULL Call Processing

*MANAGERNAME CHAR (31) NOT NULL CallProcesing

*PARAMNAME CHAR (31) NOT NULL bsslocalswitching

PARAMTYPE CHAR (15) NOT NULL Integer

PARAMLENGTH INTEGER 1

PARAMDESCRIPTION CHAR (63) BSS Local Switching

PARAMVALUE CHAR (31) NOT NULL 0

DEFAULTVALUE CHAR (31) 0

LOWVALUE CHAR (31) NULL

HIGHVALUE CHAR (31) NULL

ISMODIFIABLE TINYINT NOT NULL 1

MANAGERLIST CHAR (128) NULL

Field description for BSS UU PD

Table: SPATIAL.CONFIGPARAMS

Field Name Type Value

*NODENAME CHAR (15) NOT NULL CPSNodes

*SUBSYSTEMNAME CHAR (31) NOT NULL Call Processing

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*MANAGERNAME CHAR (31) NOT NULL CallProcesing

*PARAMNAME CHAR (31) NOT NULL Useruserie

PARAMTYPE CHAR (15) NOT NULL Integer

PARAMLENGTH INTEGER 1

PARAMDESCRIPTION CHAR (63) BSS UU PD

PARAMVALUE CHAR (31) NOT NULL 16

DEFAULTVALUE CHAR (31) 16

LOWVALUE CHAR (31) 0

HIGHVALUE CHAR (31) 255

ISMODIFIABLE TINYINT NOT NULL 1

MANAGERLIST CHAR (128) NULL

Attached diagram shows how parameter will be shown in WEM GUI. New feature is shown in red color eclipse.

Figure 61 EMS provisioning of BSS Local Switching WCS wide parameters

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5.0 UT TEST coverage

5.1 UT PLAN FOR CPCALLM For unit testing of CpCallm, following tools will be used. UTT for CsFm, MM and other process Egcp Simulator for 7540 MGW.

S.No. TEST CASE CHECK POINT

1 Enable the WCS office wide parameter for BSS local switching and with matching PD & no interception, execute a Mobile to Mobile call

WCS shall relay UUIE unmodified.

2. Disable the WCS office wide parameter for BSS local switching and execute a Mobile to Mobile call

The WCS shall not relay UUIE.

3 Enable the WCS office wide parameter for BSS local switching with ‗BSS UU PD‘ field value set to 16 for UU IE and execute a Mobile to Mobile call by setting a PD value not matching the PD value of office wide parameter

The WCS shall not relay the UU IE.

4 Call Forward Scenario Check if WCS relays the UU IE.

5 Call Wait Scenario Check if WCS relays the UU IE.

6 ECT during Alerting Check if WCS relays the UU IE.

7 Enable the WCS office wide parameter for BSS local switching with matching PD & both subscribers being Lea Subjects, execute a Mobile to Mobile call

WCS shall increment the four-bit mode field twice and relay UUIE.

8 Scenario with CAMEL Interaction Check if WCS relays the UU IE.

9 Enable the WCS office wide parameter for BSS local switching with matching PD & interception on forwarding party, execute a call-forwarding scenario with mobile subscribers.

WCS shall relay UUIE incremented by 1

10 Call Hold + New call Check if WCS relays the UU IE.

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6.0 Deployment & Maintainability

6.1 Guidelines for provisioning 6.1.1 BSS local switching feature option

The WCS will support a WCS-wide parameter allowing the operator to enable or disable this feature. When disabled, the WCS behaves as per existing implementation (no User-User IE transferred). Default value: 'disabled'

6.1.2 Protocol Discriminator of BSS inserted User-User IE

The WCS will support a WCS-wide parameter allowing the operator to configure the Protocol Discriminator of User-User IE inserted by the BSS. Range: 0 to 255 Default value: 16 (i.e. PD '00010000') The operator will not be able to edit this parameter if the BSS Local switching feature parameter is disabled.

6.2 Guidelines for Dimensioning and Capacity Describe how the feature can impact system capacity and provide the guidelines for dimensioning. 6.3 Installation requirements Describe any installation requirements including the creation/modification of installation scripts and tools. 6.4 Feature deployment path for a live customer network How to migrate from current network feature implementation to this feature

implementation when applicable?

The WCS will support a WCS-wide parameter BSS local switching feature option allowing the operator to enable or disable this feature. When disabled, the WCS behaves as per existing implementation (no User-User IE transferred). Default value: 'disabled' Should/Will this feature have the ability to be disabled?

Yes

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6.5 Guidelines for external documents Describe the impacts on customer documents for system config parameters, billing, Alarm& event, WEM GUI & WEM CLI, etc., EMS GUI will have two new WCS-wide office parameters one for the feature functionality & other for the protocol discriminator. 6.6 Debug capability N/A

7.0 Future enhancements

It is possible to introduce mechanism to determine at WCS the number

of calls locally switched. It is possible to identify and record information in CDR if the call was

locally switched or not. Support Local switching functionality on AOIP Support of local switching in MSC pool configuration

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Test Plan for BSS Local Switching UNIT 2

Chapter 6

1.0 Introduction

1.1 Feature Description

Figure 62 BSS System Level View

The current Atrium WSS does not support User-User Signaling IE inserted by UE/BSS. If the feature ―BSS Local Switching‖ is enabled by the operator the WCS will be able to support for User-User Signaling IE in the connect message inserted by BSS. The WCS will support a User-User IE received in the CONNECT message from the called mobile, and it will be forwarded in the CONNECT message to the calling mobile to trigger local switching in BSS when the BSC <-> BTS links (Abis2) are carried through satellite.

The implementation of this feature is to Support local call switching in BSS for OPEX saving (to save transmission costs) in network configurations where the BSC <-> BTS links (Abis) are carried through satellite. In addition, local switching may also allow improving the speech call quality and provide Cost effective solution for rural GSM.

2 When the BSS consists of a Base Station Controller (BSC) and one or more Base Transceiver Stations (BTS), this

(Abis) interface is used between the BSC and BTS to support the services offered to the GSM users and subscribers.

The interface also allows control of the radio equipment and radio frequency allocation in the BTS.

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Figure 63 Interfaces between BTS & BSC

The Solution is based on ALU BSS and 3rd party (Cell&Sat) products (CST, CSO, CSG) connected on the Abis interface to the BTS and BSC, requiring the MSC-S to support relaying of User to User signaling IE to trigger local switching.

In each CONNECT message from the called mobile (speech calls only), the BSS (CSO) inserts a User-User IE including certain identifiers and time-stamp. The BSS (CSO) also analyses each downlink CONNECT message to calling mobiles (speech calls only). If a User-User IE is found in a downlink CONNECT message, with same value as previously inserted in a previous uplink CONNECT, both CONNECT messages are assumed to pertain to the same call and the BSS is able to locally switch the user plane of that call. To Support the above mechanism, the WSS (MSC-S) needs to support relaying the User-User Signaling IE.

1.2 Feature Testing Scope The objective of this document is to test relay of U-U IE from WCS.

2.0 Test Environment

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2.1 Lab Configuration

Figure 64 Test Configuration 2.2 Test Equipment

1. WCS 2. EAST

3.0 Test Cases

3.1 EMS

WSS as Transit MSC

EAST ORIGINATING SIDE

(2G/3G)

TERMINATING

SIDE

(2G/3G/ISUP/BICC)

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3.1.1 Verify that a new parameter BSS Local Switching is added to System Parameters under Call Manager with default values.

TEST NUMBER: 6.1.1

PURPOSE: To verify that parameter BSS Local Switching is added to System Parameters

under Call Manager with default values.

REFERENCE: SR Number:

REGRESSION:

VERSIONS: HW - SW - EMS -

CONFIGURATION:

PRECONDITION: The load on WCS >= release 5.0

TEST DESCRIPTION:

Select Call Manager tab under System Parameters on EMS

Verify that under WCS wide parameter following fields are present - BSS Local Switching drop down is present with default value as Disabled. - Protocol Discrimination field is present with default value of 16 and is un-editable.

MESSAGE FLOW:

PASS/FAIL CRITERIA: The test case passes if:

Under WCS wide parameter following fields are present - BSS Local Switching drop down is present with default value as Disabled.

- Protocol Discrimination field is present with default value of 16. and is un-editable.

RESULT: TESTER: DATE:

PRT NUMBER:

ECR/COMMENTS:

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3.1.2 Verify that a Protocol Discriminator field can have values in range of 0-255

TEST NUMBER: 6.1.2

PURPOSE: Verify that Protocol Discriminator can have values in range of 0-255.


REGRESSION:


CONFIGURATION:

BSS local switching is enabled


TEST DESCRIPTION:


Verify that under WCS wide parameter following - Protocol Discrimination field can have values in range of 0-255. - Protocol Discrimination field doesn‘t accept values apart from 0-255 e.g. -1, 256.

MESSAGE FLOW:

PASS/FAIL CRITERIA: The test case passes if: - Protocol Discrimination field can have values in range of 0-255. - Protocol Discrimination field doesn‘t accept values apart from 0-255.


PRT NUMBER:

ECR/COMMENTS:

119

3.1.3 Verify that a Protocol Discriminator value cannot be modified when BSS local switching is disabled.

TEST NUMBER: 6.1.3

PURPOSE: Verify that Protocol Discriminator value cannot be modified when BSS local

switching is disabled.


REGRESSION:


CONFIGURATION:

BSS local switching is disabled


TEST DESCRIPTION:


Verify that under WCS wide parameter following - Protocol Discrimination field is un-editable.

- Protocol Discrimination field has default value of 16

MESSAGE FLOW:

PASS/FAIL CRITERIA: The test case passes if: - Protocol Discrimination field is un-editable.

- Protocol Discrimination field has default value of 16


PRT NUMBER:

ECR/COMMENTS:

120

3.2 Basic Calls 3.2.1 MS(2G)- MS(2G). Verify that WCS successfully relays U-U IE

TEST NUMBER: 6.2.1

PURPOSE: MS (2G) - MS (2G). Verify that WCS successfully relays U-U IE.


REGRESSION:


CONFIGURATION:

BSS local switching is enabled & PD =16


TEST DESCRIPTION:

2G Mobile originates a call to a 2G Mobile.

BSS inserts U-U IE with PD =16 in the connect message from called party.

Call gets connected successfully

Call is released successfully.

Verify that WCS relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16.

MESSAGE FLOW:


WCS relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16.


PRT NUMBER:

ECR/COMMENTS:

121

3.2.2 MS(2G)-MS(2G). Verify that WCS doesn’t relay U-U IE.

TEST NUMBER: 6.2.2

PURPOSE: MS(2G)-MS(2G). Verify that WCS doesn‘t relay U-U IE.


REGRESSION:


CONFIGURATION:

BSS local switching is disabled & PD =16


TEST DESCRIPTION:





Verify that WCS doesn‘t relay U-U IE to BSS in Connect message towards calling party.

MESSAGE FLOW:


No U-U IE in Connect message towards calling party from WCS.


PRT NUMBER:

ECR/COMMENTS:

122

3.2.3 ISUP-MS(2G). Verify that there is no change in ANM message

TEST NUMBER: 6.2.3

PURPOSE: ISUP-MS(2G). Verify that there is no change in ANM message.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

ISUP originates a call to a 2G Mobile.



Call is released successfully

Verify that there is no change in ANM message.

MESSAGE FLOW:


There is no change in ANM message.


PRT NUMBER:

ECR/COMMENTS:

123

3.2.4 MS(2G)-MS(2G). Verify that WCS doesn’t relay U-U IE.

TEST NUMBER: 6.2.4



REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:






MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

124

3.2.5 MS(2G)-MS(2G). Verify that WCS doesn’t relay U-U IE

TEST NUMBER: 6.2.5



REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:






MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

125

3.2.6 MS(3G)-MS(2G). Verify that WCS ignores U-U IE.

TEST NUMBER: 6.2.6

PURPOSE: MS(3G)-MS(2G). Verify that WCS ignores U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:





Verify that WCS ignores U-U IE to RNC in Connect message towards calling party.

MESSAGE FLOW:


WCS ignores U-U IE to RNC in Connect message towards calling party.


PRT NUMBER:

ECR/COMMENTS:

126

3.2.7 MS(2G)-MS(2G,TCSI DP12). Verify that WCS successfully relays U-U IE.

TEST NUMBER: 6.2.7

PURPOSE: MS (2G) - MS (2G,TCSI DP12). Verify that WCS successfully relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:





Verify that WCS relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16.

MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

127

3.2.8 MS(2G)-MS(2G) ETC call. Verify that WCS doesn’t relay U-U IE.

TEST NUMBER: 6.2.8

PURPOSE: MS (2G) - MS (2G) ETC call. Verify that WCS doesn‘t relay U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:


WCS sends a connect message to MSa for ETC.





MESSAGE FLOW:


WCS doesn‘t relay U-U IE to BSS in Connect message towards calling party.


PRT NUMBER:

ECR/COMMENTS:

128

3.2.9 MS(2G)-MS(2G) CSD call. Verify that WCS doesn’t relay U-U IE.

TEST NUMBER: 6.2.9

PURPOSE: MS (2G) - MS (2G) CSD call. Verify that WCS doesn‘t relay U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

2G Mobile originates a CSD call to a 2G Mobile.





MESSAGE FLOW:


WCS doesn‘t relay U-U IE to BSS in Connect message towards calling party.


PRT NUMBER:

ECR/COMMENTS:

129

3.3 Calea Scenarios 3.3.1 MS(2G, Calea)-MS(2G). Verify that WCS successfully relays U-U IE with increment in four bit mode field of U-U IE .

TEST NUMBER: 6.3.1

PURPOSE: MS(2G, Calea)-MS(2G). Verify that WCS successfully relays U-U IE with

increment in four bit mode field of U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

2G Mobile originates a call to a 2G Mobile

LEA termination of originator gets connected successfully.




Verify that WCS increments four bit mode field of U-U IE & relays U-U IE in Connect message towards calling party.

MESSAGE FLOW:


WCS increments four bit mode field of U-U IE & relays U-U IE in Connect message towards calling party.


PRT NUMBER:

ECR/COMMENTS:

130

3.3.2 MS(2G)-MS(2G,Calea). Verify that WCS successfully relays U-U IE with increment in four bit mode field of U-U IE.

TEST NUMBER: 6.3.2

PURPOSE: MS(2G)-MS(2G, Calea). Verify that WCS successfully relays U-U IE with

increment in four bit mode field of U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:


LEA termination of terminator gets connected successfully.





MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

131

3.3.3 MS(2G,Calea)-MS(2G,Calea). Verify that WCS successfully relays U-U IE with twice increment in four bit mode field of U-U IE

TEST NUMBER: 6.3.3

PURPOSE: MS(2G,Calea)-MS(2G, Calea). Verify that WCS successfully relays U-U IE with

twice increment in four bit mode field of U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:


LEA termination of originator & terminator gets connected successfully.




Verify that WCS increments four bit mode field of U-U IE twice & relays U-U IE in Connect message towards calling party.

MESSAGE FLOW:


WCS increments four bit mode field of U-U IE twice & relays U-U IE in Connect message towards calling party.


PRT NUMBER:

ECR/COMMENTS:

132

3.3.4 MSa(2G)-MSb(2G)(CFNRy)-MSc(2G,Calea). Verify that WCS successfully relays U-U IE with increment in four bit mode field of U-U IE

TEST NUMBER: 6.3.4

PURPOSE: MSa(2G)-MSb(2G)(CFNRy)-MSc(2G,Calea). Verify that WCS successfully

relays U-U IE with increment in four bit mode field of U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates a call to a MSb.

MSb is subscribed with CFNRy to MSc.

LEA termination of terminator gets connected successfully.

BSS inserts U-U IE with PD =16 in the connect message from MSc.




MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

133

3.3.5 MSa(2G,Calea,ECT during alerting)-MSb(2G)-MSc(2G). Verify that WCS successfully relays U-U IE with twice increment in four bit mode field of U-U IE

TEST NUMBER: 6.3.5

PURPOSE: MSa(2G,Calea,ECT during alerting)- MSb(2G) -MSc(2G). Verify that WCS

relays U-U IE with twice increment in four bit mode of U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. LEA termination of MSa gets connected successfully

WCS increments four bit mode field of U-U IE & BSS inserts U-U IE with PD =16 in the connect message from MSb.

Call gets connected successfully to MSb.

MSa holds MSb & calls MSc

MSa invokes ECT during alerting to MSc

LEA termination of MSa gets transferred.

WCS increments four bit mode field of U-U IE & BSS inserts U-U IE with PD =16 in the connect message from MSc.

Call gets connected successfully to MSc.


Verify that WCS increments four bit mode field of U-U IE twice & relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16

MESSAGE FLOW:


WCS increments four bit mode field of U-U IE twice & relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16


PRT NUMBER:

ECR/COMMENTS:

134

3.4 Supplementary Service Scenarios 3.4.1 MSa(2G)- MSb(2G)(CFB)-MSc(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.1

PURPOSE: MSa(2G)- MSb(2G)(CFB)-MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. MSb is subscribed to CFB to MSc.


Call gets connected successfully to MSc


Verify that WCS relays unmodified U-U IE to BSS in Connect message towards calling party with PD =16

MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

135

3.4.2 MSa(2G)- MSb(2G)(CFNRy)-MSc(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.2

PURPOSE: MSa(2G)- MSb(2G)(CFNRy)-MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. MSb is subscribed to CFNRy to MSc.





MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

136

3.4.3 MSa(2G)- MSb(2G)(CFNRc)-MSc(2G).Late Forwarding. Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.3

PURPOSE: MSa(2G)- MSb(2G)(CFNRc)-MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. MSb is subscribed to CFNRc to MSc.





MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

137

3.4.4 MSa(2G)- MSb(2G)(CFNRy)-MSc(2G)(CFB)-MSd(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.4

PURPOSE: MSa(2G)- MSb(2G)(CFNRy)-MSc(CFB)-MSd(2G). Verify that WCS relays U-U

IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. MSb is subscribed with CFNRy to MSc.

MSc is subscribed with CFB to MSd


Call gets connected successfully to MSd



MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

138

3.4.5 MSa(2G)(CH)- MSb(2G)-MSc(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.5

PURPOSE: MSa(2G)(CH)- MSb(2G) -MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:

MSa originates call to MSb. BSS inserts U-U IE with PD =16 in the connect message from MSb.



MSa hold MSb.

MSa calls MSc.





MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

139

3.4.6 MSa(2G)(CH,CW)- MSb(2G)-MSc(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.6

PURPOSE: MSa(2G)(CH,CW)- MSb(2G) -MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:




MSc calls MSa

MSa hold MSb & answers MSc.

BSS inserts U-U IE with PD =16 in the connect message from MSa.




MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

140

3.4.7 MSa(2G)(ECT)- MSb(2G)-MSc(2G). Verify that WCS relays U-U IE.

TEST NUMBER: 6.4.6

PURPOSE: MSa(2G)(ECT)- MSb(2G) -MSc(2G). Verify that WCS relays U-U IE.


REGRESSION:


CONFIGURATION:



TEST DESCRIPTION:



MSc calls MSa

MSa hold MSb & answers MSc.

BSS inserts U-U IE with PD =16 in the connect message from MSa.


MSa invokes ECT. MSb & MSc are talking.



MESSAGE FLOW:




PRT NUMBER:

ECR/COMMENTS:

142

CONCLUSION

Thus the report has discussed everything right from the Spatial Atrium to developing the test plan for BSS Local Switching. It starts with the introduction of the Spatial Atrium and then discusses the individual components i.e. WSS, WMG & WEM. The whole report is divided in 2 units- Unit 1 & Unit 2. Unit 1 tells about the Spatial Atrium and Unit 2 deals with the need and the details of the BSS Local Switching.

143

REFERNCES

www.alcatel-lucent.com www.cellnsat.com All the referred documents are from the internal sources of Alcatel-Lucent and due to the company policies the source of the documents has not been disclosed. However, all the documents are provided here, only there source is not.

http://www.alcatel-lucent.com/

http://www.cellnsat.com/

final summer report kushal alacatel

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