01 rn31551en10gla0 warming up

8/13/2019 01 Rn31551en10gla0 Warming Up

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Warming Up

1 Nokia Siemens Networks RN31551EN10GLA0

3GRPLS (RN3155) - Module 1


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At the end of this module, you will be able to

Name the structure of UTRAN specific signalling interfaces

Understand the RAB QoS parameters

Objectives



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In December 1999, the first UMTS Release was frozen. This release is commonly called UMTS Release 99.In the specification phase, two main objectives had to be met:

New radio interface solutionCore Network (CN) evolution

Mobile communication became a big business case in the 90s with unexpected growth rates.

In some areas, this imposed capacity problems. There were not enough radio resources available to supplythe subscribers in a satisfying way.

The 2nd generation mobile communication systems were still optimised for speech transmission.

UMTS Release 99


Also in the 90s, there was an unprecedented growth in data communications. This was mainly caused by theintroduction of user friendly GUIs, the browsers, to serve in the net, and by the steadily dropping costs forcomputer and router.


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Therefore, during the standardisation process, one major focus lay on the radio interface solution.

It had to be more efficient to serve more subscribers in one geographical area, resp. to allow higher datarates.On the other hand, more flexibly was required, too, so that all kinds of present and future multimediaapplications could be served.

CDMA was selected as multiple access technology for the radio interface solution. The UMTS radiointerface solution is often called WCDMA, because CDMA is used on 5 MHz.Two duplex transmission solutions are available with UMTS Release 99, one based on the TDD and onebased on the FDD mode.The introduction of a new radio interface solution required a new design of the whole radio accessnetwork, which is called UTRAN.

UMTS Release 99 (cont.)


CN evolutionThere are more than 500 GSM operators worldwide. So one requirement to UMTS Release 99 was to enablea smooth evolution from 2G to 3G. Therefore, the UMTS Rel99 CN is an enhanced GSM NSS.


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3GPP Release 4

3GPP Release 4 is a further enhancement of 3GPP Release 1999.

3GPP Release 4 contains, but is not limited to

UTRA FDD repeater function

low chip rate TDD option

700 MHz support for GERAN, e2e transparent packet streaming service

Tandem Free Operation

Transcoder Free Operation

IP transport of CN protocols

(Adopted from TR 21.902)


bearer independent CS core network CAMEL enhancements and OSA enhancements.

The 3GPP Release 4 was functionally frozen in March 2001.


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3GPP Release 5

3GPP Release 5 is a further enhancement of the previous releases.

3GPP Release 5 contains, but is not limited to,

High Speed Downlink Packet Access (HSDPA)

Initial phase of the IP Multimedia Subsystem (IMS) Wideband AMR

Location Services enhancements

UMTS in 1800/1900 MHz bands (release independent)

IP transport in the UTRAN



UTRAN sharing in connected mode and security enhancements.

The 3GPP Release 5 was functionally frozen in March 2002 and the remaining part in June 2002.


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3GPP Release 6

Release 6 (frozen 09/2005) . contains, but is not limited to

FDD Enhanced Uplink (HSUPA)

FDD Enhanced Uplink - Physical Layer

FDD Enhanced Uplink - Layer 2 and 3 Protocol Aspects

FDD Enhanced Uplink - UTRAN Iub/Iur Protocol Aspects FDD Enhanced Uplink - RF Radio Transmission/ Reception, System Performance Requirements and

Conformance Testing

Location Services enhancements 2

WLAN-UMTS Interworking Rel-6



Security

WLAN charging

USIM enhancements for WLAN Interworking

IMS Phase 2

Multimedia Messaging (MMS) enhancements

Multimedia Broadcast/Multicast Service (MBMS)

AMR-WB extension for high audio quality Push Services and Presence

Network Sharing

NOTE: Nokia/NSN RAN releases (RAN1.5, RAN04, RAS05, RAS 06, RU 10..) do not follow strictly the 3GPPreleases


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3GPP Release 7

Release 7 (closed 10/2007) with HSPA+ features:

Higher order Modulation 64QAM for the DL; 16QAM for the UL larger Peak Data rates & Capacity

MIMO Antennas: 2x2 MIMO larger Peak Data rates & Capacity

Network Architecture Improvements: Improved latency & efficiency; lower OPEX / CAPEX WLAN charging Direct Tunnelin

(Adopted from Work_plan_3gpp_rel7)


Continuous Packet Connectivity CPC / VoIP higher efficiency; more capacity; less UE battery consumption

Enhanced UE Receiver more capacity; higher UE throughput

Enhanced Cell_FACH higher throughput in Cell_FACH

L2 / RLC Optimisation less L2 overhead; higher net throughput


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3GPP Release 8 & 9

Release 8 (closed 12/2008)

Enhancements for HSPA+ evolution

64QAM & 2x2 MIMO simultaneously

Peak Rates up to 42 Mbps

. Long Term Evolution (LTE) as new radio access system

and 3GPP System Architecture Evolution (SAE) /Enhanced Packet Core EPC for GERAN, UMTS and non3GPP access

(Adopted from Work_plan_3gpp_rel8)


.

Release 9 (expected to be closed 12/2009)

LTE-Advanced (LTE-A)

3GPP proposal for IMT-Advanced (4G)

Max. Peak Rate (low Mobility) 1 Gbps DL and up to

500 Mbps (UL) Max. Peak Rate (high Mobility) 100 Mbps UL & DL

Bandwidth of up to 100 Mbps expected

Advanced MIMO-antenna systems expected


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UMTS Release 99

UMTS Release 4

UMTS Release 5

UMTS CN = enhanced GSM NSS

UTRAN & WCDMA

Bearer independent CS domain Low chip rate TDD mode UTRA repeater MMS

High Speed Downlink Packet Access (HSDPA) Wideband AMR Initial phase of the IP Multimedia Subsystem IP transport in the UTRAN Location Services enhancements

1999

2001

2002


UMTS Release 6

FDD Enhanced Uplink (HSUPA) IMS Phase 2 Wireless LAN/UMTS Inter-working Multimedia Broadcast/Multicast Service (MBMS) Push Services and Presence.

2006

UMTS Release 7

UMTS Release 8

2007

2008

HSPA+ (MIMO & Higher Order Modulation)

Enhanced UE Receiver Direct Tunneling

HSPA+ Enhancements LTE + SAE/EPS

UMTS Release 9

2009/10 LTE-A: IMT-Advanced (4G) proposal


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UMTS Release 99 Network Architecture

The UMTS CN can be organised into two main domains:CS domain

This domain offers Circuit Switched (CS) bearer services.

The CS domain is nowadays mainly used for real time data services, including speech and faxtransmission.

The network entities MSC, GMSC and VLR can be found here.

PS domain

This domain offers Packet Switched (PS) bearer services.

It is based on the GSM feature GPRS. Originally, this domain was developed for non-real timepacket switched applications, such as file transfer, email, access to the Internet.


s use o ay ma n y or . u ere are en enc es o mprove s o ere o , so a

real time services can be offered, too.The SGSN and GGSN are located in the packet switched domain. Other specified PS domainentities are the BGF and the CGF, which are often offered as stand alone devices.

There are also some network elements, which are shared by the packet switched and circuit switched domain.The common network elements comprise the HLR, AuC and EIR.

A set of network elements were specified for application provisioning, which can be also found in the CN.

Examples are the Camel Service Environment and WAP. Some service solutions affect the access network,too. See for instance LCS.


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CN (Core Network)

circuit switched (cs) domain

commoncs & ps

GERAN

PSTN/ISDN

MSC/VLR GMSC

EIRHLR

UMTS Release 99 Core Network


Packet Switched (PS) domain

elementsUTRAN WAP

corporatenetworks

PDNIP-

backbone

CGF

Billing

Centre

BGF

Inter-PLMN

Network

SGSN GGSN


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UMTS Release 4 core network

In the 3GPP R4 Core Network the MSC evolves to the MSC Server and the MGW.

The MSC Server is responsible e.g. for signalling, paging and collecting charging information while the MGWis doing a switching.

MSC Server contains a communication management functionality and is also responsible for a mobilitymanagement.

The MGW (Multimedia Gateway) main functions are:

To adapt a conventional signalling between the MSC Server or the GCS (Gateway Control Server) anddifferent network interfaces

To connect a user data from an ATM/IP backbone into the RAN or circuit switched networks


To do a transcoding and signal processing for a user plane when it's needed


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UMTS Release 4 core network



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UTRAN

The UMTS Terrestrial Radio Access Network (UTRAN) is the access network, which was developed withUMTS.

The access network is organised in Radio Network Subsystems (RNS).

Each RNS has one radio resource control unit, called Radio Network Controller (RNC).

The tasks of a RNC can be seen on one figure on the following pages.

In each RNS, there is at least one Node B active, which is connected to its Controlling RNC (CRNC)


A Node B is the 3G base station.

One or several cells can be activated with one Node B.

The main features of a Node B can be seen on one figure of the following pages.


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UTRAN

With UTRAN, four new interfaces were specified:

Iu

Iu connects UTRAN with the CN. A distinguishing is drawn between the Iu connection to the PS domain, which is labelled Iu-PS, and to the

CS domain, which is called Iu-CS.

In both cases, ATM is used as transmission network solution. Please note, that there are differences in the protocol stacks on the Iu-CS and Iu-PS interface.

Iub

This interface is used between the Node B and its controlling RNC.Iur


s s an n er- n er ace, connec ng wo ne g our ng .

It is used among others in soft handover situations, where a UEs active cells are under the control of morethan one RNC.

One RNC is responsible for the UE; it is called Serving RNC (SRNC). The remaining RNCs in a connectionare called Drift RNC (DRNC).

Uu

Uu is the acronym for the WCDMA radio interface.

On the interfaces Iu, Iur, and Iub, ATM is used for the transport of user data and higher layer signallinginformation.


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CN

circuitswitched

(cs)

domain

UTRAN

Radio Network Subsystem (RNS)

Iub Iu-CS

Uu

Uu

UE

MSC/VLR

RNC

UTRAN


packet

switched(ps)domain

Radio Network Subsystem (RNS)

Iub

Iur

Iu-PS

UE

SGSNRNC


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WCDMA radio resource managementAdmission Control, Packet Scheduling,Load Control, Power Control, Handover

Control, Resource Manager. Telecom functionality

incl. Location & connection management(Transport Manager), ciphering, Iu and Iub

RNC Tasks and Functions


c anne managemen , sw c ng anmultiplexing

Maintenanceincl. Fault localisation and reconfiguration

Operation

incl. RNC and Node B parametermodification


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Uu InterfaceWCDMA

O&M Processing.Interfacing with NMSand RNC for alarm

and control

(Operations andMaintenance)

functions.

Radio Channel functions.Transport to physical channelmappings. Encoding/Decoding Spreading/Despreading user

traffic and signalling.

Node B Tasks and Functions in Rel 99


Iub InterfaceATM

Cellular Transmission managementManaging ATM switching andmultiplexing over the Iub interface.Control of AAL2/AAL5 connections.Control of the physical transmission

interfaces E1, PDH, SDH ormicrowave.

Air Interface management.Controlling Uplink andDownlink radio paths on the UuAir Interface. Baseband to RF

conversion. Antenna multi-coupling.


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Two radio interface solutions were specified with UMTS Release 99:

FDD mode(high chip rate) TDD mode

The used carrier frequency band is 5 MHz.

The radio interface is organised in 10 ms frames, which are divided into 15 timeslots.72*10 ms frames represent one hyperframe, which was introduced for UMTS-GSM Handovers.

The information bearing stream is spread with the so-called spreading code.The spreading code consists of 3.84 Mcps.

Key WCDMA Facts


The spreading code is a composition of two codes, Scrambling codes and channelisation codes

Different types of handovers are supported: soft handover (FDD only) , softer handover (FDD only), and hardhandovers.

Hand handovers can be classified into intra-frequency, inter-frequency, and inter-RAT handovers.

The modulation is QPSK in UMTS Release 99.


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Scrambling CodesThe scrambling codes are derived from the Gold code family.They represent pseudo noise sequences.As a consequence, if there is multi-path propagation in the system, the individual multi-paths can bedetected due the scrambling codes.There are 512 primary scrambling codes defined for the downlink transmission.Uplink, several million scrambling codes are available.A scrambling code repeats with every 10 ms frame.

Channelisation CodesThe channelisation code are used for channel separation within one multi-path.

Key WCDMA Facts


e c anne sa on co es are or ogona co es.

They repeat with each information bit, which has to be transmitted. Data rates and channelisation codesare consequently related.Uplink, user data and control data are code multiplexed on one physical channel.Downlink, they are time multiplexed.


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Duplex Transmission Modes: Frequency Division Duplex (FDD) Time Division Duplex (TDD)

Multiple Access: Code Division Multiple Access (CDMA)

Modulation Quadrature Phase Shift Keying (QPSK)

Spreading Spreading codes =

channelisation codes scrambling codes Chip rate: 3.84 Mchips

Channelisation codes = orthogonal codes,length: depends on spreading factor

Scrambling codes = pseudo noise codes(derived from Gold code family)length: 38400 chips (10 ms)

Key WCDMA Facts in Rel 99


-

Bandwidth 5 MHz

Time Organisation: 10 ms per radio frame 15 time slots per frame 72 radio frames per hyperframe 2560 chips per timeslot

Spreading Factors (FDD mode): UL: 4, 8, 16, 32, 64, 128, 256 DL: 4, 8, 16, 32, 64, 128, 256, 512The spreading factor can be changed every

TTI (10, 20, 40, or 80 ms).

Handover types: Soft & Softer HO (FDD only),Hard Handover;


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Strata were introduced to group protocols related to one aspect of service. In this course, especially theAccess Stratum is of importance.

The Access Stratum (AS) comprises infrastructure and protocols between entities of the infrastructurespecific to the applied access technique. In UMTS it offers services related to the data transmission via theradio interface. It also allows the management of the radio interface on behalf of other parts of the network.

Two access strata are defined in UMTS:

UTRAN MTThe protocols in use between UTRAN and the mobile phone specify in detail radio interfacerelated information. AS signalling is used to inform the UE about how to use the radio interface inthe UL and DL direction.

Access Stratum


UTRAN CN

The CN requests the access network to make transmission resources available. The interactionbetween UTRAN and the CN is hereby independent of the interaction between the UTRAN andthe UE. In other words, the UTRAN CN access stratum is independent of the used radiointerface technology.

In this course, we focus our interest mainly on the transmission of signalling information and related

parameters via the radio interface. Consequently, the access stratum between the UE and UTRAN will bediscussed in detail. But also Non Access Stratum (NAS) signalling will be outlined. NAS signalling isexchanged between the UE and the serving network. In this course material, this signalling is regarded aspart of the non-access stratum.


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UTRAN

UE CN Iu edge node

NAS signalling and User datai.e. MM, PMM & CC, SS, SMS, SM

AS and NAS Signalling


Access Stratum Signalling(Uu Stratum)

RRC

Access Stratum Signalling(Iu Stratum)

RANAP


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When a subscriber requests a network service, he expects to get and is willing to pay for a specific end-to-end quality of service.

In a peer-to-peer communication, the QoS has to be provided between the two participating terminals. TheQoS of an end-to-end bearer service has to be described. Parameter such as minimum bit rate, guaranteedbit rate, and end-to-end delay can be used.

An end-to-end bearer service may be made available by several operators. This is the situation displayed in

the figure on the right hand side. The UMTS provider offers the UMTS bearer service, a service establishedbetween the UE and a CN edge node (GMSC, GGSN). The UMTS bearer service and its QoS depends on the underlying bearer services:

The CN bearer service and the Radio Access Bearer (RAB) Service. The signalling protocols RANAP between the CN Iu edge node (MSC/VLR, SGSN) and the RNC is used

among others to establish, maintain, modify and release the Iu Bearer Service, which is required to

UMTS QoS Architecture


establish the RAB between the CN Iu edge node and the S-RNC. Between the S-RNC and the UE, the

signalling and control protocol RRC is used to establish Radio Bearer (RB) Services, which is also requiredto establish a RAB Service.

The RRC is used peer-to-peer between the UE and the S-RNC. There are two intermediate devices, whichalso have to be informed about the bearer management: The Node B and during a soft handover the D-RNC. The management of the Iub resources to offer adequate QoS to higher layer bearer services is donewith the NBAP. This protocol is also used to inform the Node B about the transmission and reception of

common and dedicated information on the radio interface Uu. The RNSAP is used between neighbouringRNCs for features such as inter-RNC soft handovers and S-RNC relocation.


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TE TECN

GatewayMT UTRANCN Iu

edge node

End-to-End Service

TE/MT LocalBearer Service

ExternalBearer Service

UMTS Bearer Service = UMTS QoS



CNBearer Service

Radio AccessBearer Service

BackboneBearer Service

RadioBearer Service

IuBearer Service

UTRA FDD/TDDService

PhysicalBearer Service

(adopted from TS 23.107)


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TE ext. networkCN GatewayMT UTRAN CN Iu edge node

UMTS BSManager

UMTS BSManager

UMTS BSManager

RAB

Subscr

Control

Adm/

Cap.

Control

Adm/

Cap.

Control

Trans-

lation

Adm/

Cap.

Control

Adm/

Cap.

Control

Trans-

lation

QoS Management Functions in the Control Plane


Manager

CN BS

Mana-

ger

Iu BS

Mana-

ger

Ext. BS

Mana-

ger

CN BS

Mana-

ger

Iu BS

Mana-

ger

RadioBS

Mana-

ger

RadioBS

Mana-

ger

LocalBS

Mana-

ger

BB NS

Mana-

ger

Iu NS

Mana-

ger

BB NS

Mana-

ger

Iu NS

Mana-

ger

UTRA

ph. BS

Mana-

ger

UTRA

ph. BS

Mana-

ger

(adopted fromTS 23.107)


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3G-MSC/VLR

UE Node BRNC

RNS

RRC

UTRAN Specific Signalling and Control Protocols


3G-SGSN

RNCRNS

Iur: RNSAP


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In UMTS, four QoS classes have been defined: Conversational class

is the QoS class for delay sensitive real time services such as speech telephony. Streaming class

is also regarded as real-time QoS class. It is also sensitive to delays; it carries traffic, which looks realtime to a human user. An application for streaming class QoS is audio streaming, where music files are

downloaded to the receiver. There may be an interruption in the transmission, which is not relevant forthe user of the application, as long as there are still enough data left in the buffer of the receivingequipment for seamless application provision to gap the transmission time break.

Interactive classis a non-real time QoS class, i.e. it is used for applications with limited delay sensitivity (so-calledinteractive applications). But many applications in the internet still have timing constraints, such as http,



ftp, telnet, and smtp. A response to a request is expected within a specific period of time. This is the

QoS offered by the interactive class. Background class

is a non-real time QoS class for background applications, which are not delay sensitive. Exampleapplications are email and file downloading.

A set of UMTS bearer attributes have been defined to specify the UMTS service. They are listed on the righthand side. When a UMTS bearer is established, modified or released, aspects such as the UE capabilities,

subscription profiles and network specific QoS profiles have to be taken under consideration.


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Backgroundclass

Interactiveclass

Streamingclass

Traffic class

Maximum bit rate

SDU formatinformation

SDU error ratio

Delivery order

Maximum SDU size

Conversationalclass

UMTS Bearer Attributes


Residual biterror ratio

Delivery oferroneous SDUs

Transfer delay

Guaranteed bit rate

Traffic handlingpriority

Allocation/Retentionpriority

(adopted from TS 23.107 chap. 6.4.3.3)


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Services and traffic class

Different services and applications set different requirements for the connection over the radio access network(RAN), i.e. radio access bearer (RAB)

Minimum bit rate

Delay

Error protection

These different quality requirements can be met by selection of traffic classConversational class The most well known use of this scheme is telephony speech (e.g. GSM). But with Internet and multimedia a

number of new applications will require this scheme, for example voice over IP and video conferencing tools.Real time conversation is always performed between peers (or groups) of live (human) end-users. This is theonly scheme where the required characteristics are strictly given by human perception.

(adopted from TS 23.107)


ream ng c ass

When the user is looking at (listening to) real time video (audio) the scheme of real time streams applies.The real time data flow is always aiming at a live (human) destination. It is a one way transport. This schemeis one of the newcomers in data communication, raising a number of new requirements in bothtelecommunication and data communication systems. It is characterised by that the time relations (variation)between information entities (i.e. samples, packets) within a flow shall be preserved, although it does nothave any requirements on low transfer delay.

Interactive class When the end-user, that is either a machine or a human, is on line requesting data from remote equipment

(e.g. a server), this scheme applies. Examples of human interaction with the remote equipment are: webbrowsing, data base retrieval, server access. Examples of machines interaction with remote equipment are:polling for measurement records and automatic data base enquiries (tele-machines).

Background class When the end-user, that typically is a computer, sends and receives data-files in the background, this

scheme applies. Examples are background delivery of E-mails, SMS, download of databases and receptionof measurement records.


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Traffic classBackground

classInteractive

classStreaming

classConversational

class

Speech

Streaming audio

Video call

Streaming video

Services/applications and traffic class


Email

Email (background)

VoIP

Gaming

Presence

Initially 3G networks do not support all traffic classes and services are implemented with lowerquality connections.


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The general protocol model for UTRAN interfaces can be seen in the figure on the right hand side.It is organised in horizontal and vertical planes.

There are two main vertical layers:The control plane is used for signalling and control.

UTRAN specific signalling protocols had been developed, such as the RNSAP. This is oneexample of an application protocol, as denoted in the figure.Each signalling and control protocol requires a signalling bearer.The signalling bearers in UMTS are based on standard bearer protocols (e.g. ATM).

The user plane describes the user data transport.The data streams are transmitted via data bearers.

General Protocol Model for UTRAN Interfaces


Within the transport network layers, there are vertical transport network user and control planes.

A transport network control plane is responsible for the transport of higher layer data.The transmission resources for the control plane are made available by operation and maintenance.The Transmission resources for the user data streams can be made available on demand. On someinterface, ALCAP is used.It is a transport network control plane specific signalling protocol to establish, maintain, modify, andrelease data bearers. It is for instance in use on the Iu-CS interface, but not on the Iu-PS interface. The

signalling bearers for ALCAP are always set up by operations and maintenance.


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Control Plane User PlaneRadioNetworkLayer

TransportNetworkLayer

ApplicationProtocol

DataStreams

Transport NetworkControl Plane User Plane

Transport Network

User Plane

Transport Network



Physical Layer

(copied from TS 25.401 chap. 11.1.1)

SignallingBearer(s)

SignallingBearer(s)

DataBearer(s)


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The figure on the right hand side shows the Uu access stratum protocols as implemented in the UE.

The UE protocol stack can be divided into a control and a user plane.

The L3 protocol RRC is used to inform the UE about the use of the uplink and downlink radio resources.

The RRC protocols peer entities are the RNC and the Node B.

The receiving entity has to configure the L2 (MAC, PHY, PDCP, and BMC) protocol entities in accordance tothe received commands.

MAC: Medium Access Control



PHY: Physical layer

PDCP: Packet Data Conversion ProtocolBMC: Broadcast/multicast control

The protocol stacks for signalling and user data transfer can be seen with the two figures, which follow thenext one.


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RLC Layer

Control Plane Signalling User Plane Signalling

RRC Layer

RLCRLC

RLCRLC

BMC

PDCP

PDCPPDCP

RBs

controlcontrol

control

controlcontrol

Radio Interface Protocol Architecture (in UE)


MAC Layer

PHY Layer

(copied from TS 25.301 chap. 5.1)

TrCHs

RLC RLC

PhyCHs

LogCHs


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For this course module, following 3GPP specifications were used:

TR 21.902, Evolution of 3GPP system TS 23.002, Network architecture TS 23.101, General UMTS Architecture TS 23.107, Quality of Service (QoS) concept and architecture TS 25.301, Radio interface protocol architecture TS 25.308, UTRA HSDPA; Overall description; Stage 2 TS 25.401, UTRAN overall description TR 25.876, MIMO in UTRA TS 25.308, HSDPA Overall Description TS 25.309, FDD Enhanced Uplink (HSUPA) Overall Description

References


TS 36.300, E-UTRA and E-UTRAN Overall Description

TR 36.913, LTE-Advanced

TS Technical SpecificationTR Technical Report

Remark:

Most of these Specifications are available in different versions, mainly depending on the 3GPP Release.HSDPA is only available starting with Release 5; therefore, HSDPA is only contained in Version 5 or laterspecifications. Release 99 is referred to as Version 3. Modifications within one release are possible,resulting in running numbers.

Example: TS 25.401 V3.10.0 gives an overall description of UTRAN based on Release 99. 10.0 refers to 10(by 3GPP) approved versions with minor corrections.

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