Service Function Chaining in Mobile Networks Status draft-haeffner-sfc-use-case-mobility IETF 89 London, 3 March 2014 Service Function Chaining WG Walter Haeffner - Jeff Napper - Martin Stiemerling - Diego R. Lopez - IETF 89 - London, UK - 3 March 20141
draft-haeffner-sfc-use-case-mobility acknowledgement IETF 89 - London, UK - 3 March We thankLinda 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-mobility 1 – context IETF 89 - London, UK - 3 March GPP Mobile Network> SFC < P-GW PCRF DC Appl. per user policy and charging enforcement YouTube bing iTunes IPTV 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-mobility 2 - objectives IETF 89 - London, UK - 3 March Understand importance of Service Function Chaining for mobile network operators - Influence to their business Discuss Service Function Chains (SFC) in the context of mobile network architectures – exemplary state of the art use cases Work out potential weaknesses in current environments and derive 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-mobility 3 – status draft IETF 89 - London, UK - 3 March Draft-00 issued 29 Jan 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 Added 3GPP R11 Traffic Detection Function (TDF) [3GPP TS ] Allows for fine grained classification schemes and feedback to PCC
draft-haeffner-sfc-use-case-mobility 3 – status draft - basics of a video optimization SFC IETF 89 - London, UK - 3 March Functional view of a model video optimizer SFC DPI Video Opt. DPI Video Opt. P-GWLB FW classified “web service” classified “port 80” “non-port 80” classified “video” “port 80 no video” Crtl DPI Video Opt. e.g. VoIP Cache Draft-00 & draft-01 shows flow steering based on HTTP redirections
draft-haeffner-sfc-use-case-mobility 4 – outlook draft-02 to be published end of March IETF 89 - London, UK - 3 March Discuss impact of re-classification and chains of value added services. GW PCRF 4G (LTE) 3G (UMTS) move Video SFC RAT RAT = 4G : opt.off RAT = 3G : opt. DPI Malware Prevention Port 80 Action/Forwarding based on NW Load VAS
draft-haeffner-sfc-use-case-mobility 5 – outlook draft-02 to be published end of March IETF 89 - London, UK - 3 March Grown multi-vendor structures may become very complex, inefficient, hard to understand and hard to manage P-GW PCRF FW Web APN classified port 80 LB DPI Analytics Web APN LB DPI Malware Prev. Parental Control Web APN classified port 80, non-video CRTL DPI Video Opt. LB TCP Opt. classified video classified non-port 80 re-classify RAT vendor avendor cvendor b Video Cache does not reflect wiring and actual packet flow!
draft-haeffner-sfc-use-case-mobility 5 – Weaknesses and Requirements IETF 89 - London, UK - 3 March 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-mobility 6 – IETF SFC interactions with 3GPP PCC architecture IETF 89 - London, UK - 3 March How to exchange 3GPP user & control plane metadata with IETF SFC? Subscription Profile Repository PCRF Application Functions Access Network Gateway P-GW PCEFBBERF Online Charging System Offline Charging System IETF SFC-1 Metadata Exchange ? IETF SFC-n 3GPP PCC IETF SFC Sp GxGxxGy SyRx Sd BBERF: Bearer Binding and Event Reporting Function IETF SFC Classifier [DPI] “3GPP Classifier” TDF IF ?
draft-haeffner-sfc-use-case-mobility 7 – outlook draft-IETF 90 IETF 89 - London, UK - 3 March Listed all use case classes required to verify universality of SFC WG architecture and design paradigms for mobile. Isolate input to requirements and functional specifications. SFCs for fixed networks (xDSL, Cable) are typically a subset of what is seen in mobile. List synergies w.r.t. FMC scenarios. Analyse requirements for the interaction between the 3GPP and the IETF SFC classification schemes. Initiate a discussion to clarify how to proceed in case of encrypted traffic (IETF 88 resolution).