Service Function Chaining in Mobile NetworksStatus draft-haeffner-sfc-use-case-mobility

IETF 89 London, 3 March 2014Service Function Chaining WG

Walter Haeffner - walter.haeffner@vodafone.com, Jeff Napper - jenapper@cisco.comMartin Stiemerling - mls.ietf@gmail.com, Diego R. Lopez - diego@tid.es

IETF 89 - London, UK - 3 March 2014 1

draft-haeffner-sfc-use-case-mobilityacknowledgement

IETF 89 - London, UK - 3 March 2014 2

We thank Linda Dunbar

Ron Parker

Wim Hendericks

Alla Goldner

Dave Dolson

Peter Bosch

Praveen Muley

Carlos Correia, ...... for valuable comments

caches

protect network & privacy – FW, IDS, ACL, ...optimize transport & payload – TCP Opt., Video Opt., ...

functions required for technical reasons – GC-NAT, DPI, LB, ...merge signaling information into data flow - HTTP header enrichment, ...

network-based value added services – parental control, malware protection, ...

draft-haeffner-sfc-use-case-mobility1 – context

IETF 89 - London, UK - 3 March 2014 3

3GPP Mobile Network > SFC <P-GW

PCRF

DCAppl.

@Appl.

per userpolicy and charging

enforcement

• YouTube• bing• iTunes

• IPTV• eMail• VoIP

Mobile network operators need to implement a complex array of single- (or few-) function devices ( a.k.a. SFC) to control data traffic such that they can achieve their business goals.

draft-haeffner-sfc-use-case-mobility2 - objectives

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Understand importance of Service Function Chaining formobile network operators - Influence to their business

Discuss Service Function Chains (SFC) in the context of mobilenetwork architectures – exemplary state of the art use cases

Work out potential weaknesses in current environments andderive operator requirements to support SFC WG objectives

Compare with activities of other standard bodies, especially clarify interaction between 3GPP and IETF SFC approach

A possible dream SFC environment from an operator’s point of view based on NFV, SDN, reflecting abstraction levels ....

draft-haeffner-sfc-use-case-mobility3 – status draft

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Draft-00 issued 29 Jan. 2014 Service chains supplement 3GPP policy and charging control architecture

PCC and SFCs play a significant role in mobile service specifications

SFCs often a sequence of “little” proprietary SFC implementations

Therefore typically a hierarchy of inspections & classifications in place

Discussed simple classification and flow steering schemes

Sketched use case “video optimization” (L7) and “TCP optimization” (L4)

Discussed weakness of current solutions and requirements to SFC WGs Draft-01 issued 14 Feb. 2014

Added 3GPP R11 Traffic Detection Function (TDF) [3GPP TS.23.203]

Allows for fine grained classification schemes and feedback to PCC

draft-haeffner-sfc-use-case-mobility3 – status draft - basics of a video optimization SFC

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Functional view of a model video optimizer SFC

DPI VideoOpt.

DPI VideoOpt.

P-GW LB LB FWNAT @

classified“web service”

classified“port 80”

“non-port 80”

classified“video”

“port 80 no video”

CrtlDPI

VideoOpt.

e.g. VoIP

Cache

Draft-00 & draft-01 shows flow steering based on HTTP redirections

draft-haeffner-sfc-use-case-mobility4 – outlook draft-02 to be published end of March

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Discuss impact of re-classification and chains of value added services.

GW

PCRF

4G (LTE)

3G (UMTS)

moveVideo

SFC

RAT

RAT = 4G : opt .offRAT = 3G : opt. on

@

DPI

MalwarePrevention

Port 80

Action/Forwardingbased on NW Load

@

Load

VAS

draft-haeffner-sfc-use-case-mobility5 – outlook draft-02 to be published end of March

IETF 89 - London, UK - 3 March 2014 8

Grown multi-vendor structures may become very complex, inefficient, hard to understand and hard to manage

P-GW

PCRF

FWNAT @Web

APN

classified port 80

LBDPI

Analytics

Web

APN

LBDPI

MalwarePrev.

ParentalControl

Web

APN

classified port 80, non-video

CRTLDPI

VideoOpt.

LB

TCPOpt.

classified video

classified non-port 80

re-classify RAT

vendor a vendor cvendor b

VideoCache

does not reflect wiringand actual packet flow!

draft-haeffner-sfc-use-case-mobility5 – Weaknesses and Requirements

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Weaknesses in current deployments Per APN service chaining, in almost any case classification too coarse grained Means traffic often unnecessarily traverses a service function, no offloading Often ad hoc sequence of individual mini-chains, each with its own classification Results in multiple, individual DPI inspection systems, multiple LB batteries Is expensive, complex, inflexible, hard to modify/extend with reduced performance Possible solutions Mobile network MUST exchange context with the IETF SFC classifier function SFC classifier MUST tag packets such that these enter only the SFs required Means bi- and unidirectional flows MUST be allowed Individual SFs MUST participate in multiple, different SFCs Creation/modification of SFCs including their branching rules SHOULD be done

in a simple to use SFC editor. Mapping onto the underlay MUST then be automatic.

draft-haeffner-sfc-use-case-mobility6 – IETF SFC interactions with 3GPP PCC architecture

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How to exchange 3GPP user & control plane metadata with IETF SFC?

Subscription Profile Repository

PCRF

ApplicationFunctions

Access NetworkGateway P-GW

PCEFBBERF

OnlineCharging System

OfflineCharging System

IETFSFC-1

Metadata Exchange ?

IETFSFC-n

3GPP PCCIETF SFC

Sp

GxGxx Gy

SyRx

Sd

BBERF: Bearer Binding and Event Reporting Function

IETFSFC

Classifier[DPI]

“3GPP Classifier”

TDF

IF ?

draft-haeffner-sfc-use-case-mobility7 – outlook draft-IETF 90

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Listed all use case classes required to verify universalityof SFC WG architecture and design paradigms for mobile.

Isolate input to requirements and functional specifications.

SFCs for fixed networks (xDSL, Cable) are typically a subsetof what is seen in mobile. List synergies w.r.t. FMC scenarios.

Analyse requirements for the interaction between the 3GPPand the IETF SFC classification schemes.

Initiate a discussion to clarify how to proceed in case of encrypted traffic (IETF 88 resolution).