network function virtualization (nfv): conception, present and … · verizon selected the european...

Network Function Virtualization (NFV): Conception, Present and Future

Rashid MijumbiUniversitat Politecnica de Catalunya, Barcelona, Spain

[email protected]/rashid

Telecommunications Software and Systems Group (TSSG)Waterford, September 2015

mailto:[email protected]

http://www.maps.upc.edu/rashid

Outline

Motivation for NFV

NFV Timeline

Concept / Definition

Expected gains

Examples / Use cases

NFV Architecture

Relationship with SDN

State-of-the-art

Research Challenges

Motivation for NFV

40

60

80

100

120

140

160

180

2014 2015 2016 2017 2018 2019

Exab

ytes

per m

onth

Source: Cisco VNI Global IP Traffic Forecast, 2014–2019. May 2015.

1 exabyte = 1 000 000 000 gigabytes

Expand/Change Networks’ proprietary equipment

1

2

Increased CAPEX and OPEX

Continuously increasing user requirements:

- rapidly changing service demands require short development cycles

- even more data, Global IP Traffic Trend

Motivation for NFV (2)

Increased competition among each other and from O-T-T providers

Limited possibility to raise subscription fees

Continuous reduction in ARPU, PROFITABILITY

13 Operators Call for Action

A joint operator call for the Telecom and IT industry to take advantage of advances in virtualization to increase service

agility, network flexibility and reduce CAPEX and OPEX

October 2012

http://portal.etsi.org/NFV/NFV_White_Paper.pdf

ETSI responds to Call

- AT&T, BT, Deutsche Telekom, Orange, Telecom Italia, Telefonica andVerizon selected the European Telecommunications Standards Institute(ETSI) to be the home of the Industry Specification Group for NFV

- Now 270 individual companies including 38 of the world’s major serviceproviders as well as representatives from both telecoms and IT vendors

November 2012

- 1st Phase of work ended at end of 2014, 11 documents: architecturalframework, descriptions of the infrastructure, management andorchestration, security and trust, resilience and service quality metrics.

http://www.etsi.org/news-events/news/864-2015-01-press-etsi-network-functions-virtualisation-completes-first-phase-of-work

So, what is NFV ? http://portal.etsi.org/NFV/NFV_White_Paper.pdf

NFV Concept

Leverage advances in virtualization to decouple network functions from Hardware

Anticipated Benefits- Reduced capital expenses (CAPEX)

- Due to economies of scale and more efficient use of resources

(scale up/down),

- Reduced operation expenses (OPEX)

- Power/energy, space, update/upgrade/maintenance

- Flexible, faster deployment, reducing time to market

- Minimizing typical operator innovation cycle. Automated, standard

deployment

1

2

3

Some examples: Customer Premises Equipment

Evol

ved

Pack

etCo

re

Access Network (E-UTRAN)

User Equipment

Evolved Packet Core (EPC)

eNodeB eNodeB

S-GW MME

PCRF P-GW

External Networks


User Equipment

VNFs

eNodeB eNodeB

S-GW

MME

PCRF

P-GW

External Networks

Data Centers


User Equipment

Evolved Packet Core (EPC)

eNodeB eNodeB

S-GW MME

PCRF P-GW

External Networks

Presenter

Presentation Notes

Virtualizing the Evolved Packet Core (EPC) is another example of NFV that has attracted a lot of attention from industry. The EPC is the core network for Long Term Evolution (LTE) as specified by 3GPP [8]. On the left side of Fig. 3, we show a basic architecture of LTE without NFV. The User Equipment (UE) is connected to the EPC over the LTE access network (E-UTRAN). The evolved NodeB (eNodeB) is the base station for LTE radio. The EPC performs essential functions including subscriber tracking, mobility management and session management. It is made up of four NFs: Serving Gateway (S-GW), Packet Data Network (PDN) Gateway (P-GW), Mobility Management Entity (MME), and Policy and Charging Rules Function (PCRF). The EPC is connected to external networks, which may include the IP Multimedia Core Network Subsystem (IMS). In the current EPC, all its functions are based on proprietary equipment. Therefore, even minor changes to a given function may require a replacement of the equipment. The same applies to cases when the capacity of the equipment has to be changed. On the right side of Fig. 3, we show the same architecture in which the EPC is virtualized. In this case, either all functions in the EPC, or only a few of them are transferred to a shared (cloud) infrastructure. Virtualizing the EPC has the potential to lead to better flexibility and dynamic scaling, and hence allow TSPs to respond easily and cheaply to changes in market conditions. For example, as represented by the number of servers allocated to each function in Fig. 3, there might be a need to increase user plane resources without affecting the control plane. In this case, VNFs such as a virtual MME may scale independently according to their specific resource requirements. In the same way, VNFs dealing with the data plane might require a different number of resources than those dealing with signaling only. This flexibility would lead to more efficient utilization of resources. Finally, it also allows for easier software upgrades on the EPC network functions, which would hence allow for faster launch of innovative services.

NFV Reference Architecture

Physical Resources

Virtual Resources

Virtual Network Functions

Computing, Storage, Network Resources

Computing, Storage, Network Resources

Network Function Virtualization InfrastructureNFV

Management &

Orchestration

(NFV MANO)

VNF 1 VNF 2 VNF 3 VNF N

1

2

3. . .

Software Defined Networking

Distributed Control and Middleboxes

(e.g. Firewall, Intrusion Detection, etc.) in

Traditional NetworksLogical Layers in a Software

Defined Network

NFV SDN

Decouples control plane from data plane to enable faster innovation,

network flexibility and holistic management

Decouples functions from hardwareto reduce network operator CAPEX

and OPEX, and increase service agility

Service/Function Abstraction Networking Abstraction

Automation

Agility

Isolation

OpenFlow de-facto standard

Multiple Control Protocols (e.g NETCONF, SNMP)

Mainly Telecom service providers

Mainly networking software and hardware vendors

NFV and SDN are highly related and complimentary, combining them may lead to greater value. BUT they are not dependent on each other

Relationship between SDN and NFV

State-of-the-art (1): Standardization Activities

There is sufficient involvement of standards bodies in NFVactivities.

While many of them work in liaison with the ETSI, some ofthem such as ATIS and 3GPP SA5 have identified and areworking on specific aspects of NFV that have not yet beensufficiently developed by the ETSI.

What remains to be seen is whether the output in terms ofstandards will match with the speed at which vendors andTSPs propose NFV solutions.

State-of-the-art (2): Collaborative Projects

It is interesting to observe that all the three industrial projects(ZOOM, OPNFV and OpenMANO) are focused on MANO. Thisunderlines the importance of MANO in NFV.

MANO is a critical aspect towards ensuring the correctoperation of the NFVI as well as the VNFs.

Like the decoupled functions, NFV demands a shift fromnetwork management models that are device driven to thosethat are aware of the orchestration needs of networks with bothlegacy equipment and VNFs.

State-of-the-art (3): Commercial Products

Although NFV is gaining momentum, it is still an emergingtechnology and solutions based on final specifications, andwidespread deployments for end-users may take a few years toappear.

Many organizations/vendors/operators are investing in and arewilling to test NFV-based solutions.

It can be observed from these early implementations andplatforms, that two aspects re-appear in a big number of them:

(1) the high focus on open source, and(2) the ability of current SDN and cloud technologies tosupport NFV.

A lot of progress, yet many challenges and questions open for research . . .Management and Orchestration

Standardization

Efficient resource allocation

Energy efficiency

Efficient Resource Allocation

Architectural design

Information and data modeling

PerformanceManagement of SDNInter-operability

Presenter

Presentation Notes

Even with all the anticipated benefits, and despite the immense speed at which it is being accepted by both academia and industry, NFV is still in early stages. There still remain important aspects that should be investigated and standard practices which should be established.

References[1] Rashid Mijumbi, Joan Serrat, Juan-Luis Gorricho, Niels Bouten, Filip De Turck, Raouf Boutaba, “Network Function Virtualization:

State-of-the-art and Research Challenges”. IEEE Communications Surveys and Tutorials. Accepted September 2015

[2] Rashid Mijumbi, Joan Serrat, Juan-Luis Gorricho, Niels Bouten, Filip De Turck, Steven Davy, “Design and Evaluation of Algorithms

for Mapping and Scheduling of Virtual Network Functions”, IEEE Conference on Network Softwarization (NetSoft). University

College London. 13-17 April 2015

[3] Rashid Mijumbi, Joan Serrat, Juan-Luis Gorricho, ”Self-managed Resources in Network Virtualization Environments”, IFIP/IEEE

International Symposium on Integrated Network Management (IM), Ottawa Canada, May 2015. Dissertation Digest Paper.

[4] Rashid Mijumbi, Joan Serrat, Juan-Luis Gorricho, Javier Rubio-Loyola and Steven Davy, “Server Placement and Assignment in

Virtualized Radio Access Networks”, IEEE/IFIP CNSM, International Workshop on Management of SDN and NFV Systems,

Barcelona, Spain. Accepted September 2015

network function virtualization (nfv): conception, present and … · verizon selected the european...

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