1. 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 - walter.haeffner@vodafone.com, Jeff Napper - jenapper@cisco.comwalter.haeffner@vodafone.comjenapper@cisco.com Martin Stiemerling - mls.ietf@gmail.com, Diego R. Lopez - diego@tid.esmls.ietf@gmail.comdiego@tid.es IETF 89 - London, UK - 3 March 20141

2. draft-haeffner-sfc-use-case-mobility acknowledgement IETF 89 - London, UK - 3 March 20142 We thankLinda Dunbar Ron Parker Wim Hendericks Alla Goldner Dave Dolson Peter Bosch Praveen Muley Carlos Correia,...... for valuable comments

3. 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 2014 3 3GPP Mobile Network> SFC < P-GW PCRF DC Appl. @ Appl. per user policy 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.

4. draft-haeffner-sfc-use-case-mobility 2 - objectives IETF 89 - London, UK - 3 March 20144  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....

5. draft-haeffner-sfc-use-case-mobility 3 – status draft IETF 89 - London, UK - 3 March 20145  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

6. draft-haeffner-sfc-use-case-mobility 3 – status draft - basics of a video optimization SFC IETF 89 - London, UK - 3 March 20146 Functional view of a model video optimizer SFC DPI Video Opt. DPI Video Opt. P-GWLB FW NAT @ 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

7. draft-haeffner-sfc-use-case-mobility 4 – outlook draft-02 to be published end of March IETF 89 - London, UK - 3 March 20147 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. on @ DPI Malware Prevention Port 80 Action/Forwarding based on NW Load @ Load VAS

8. draft-haeffner-sfc-use-case-mobility 5 – outlook draft-02 to be published end of March IETF 89 - London, UK - 3 March 20148 Grown multi-vendor structures may become very complex, inefficient, hard to understand and hard to manage P-GW PCRF FW NAT @ 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!

9. draft-haeffner-sfc-use-case-mobility 5 – Weaknesses and Requirements IETF 89 - London, UK - 3 March 20149 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.

10. draft-haeffner-sfc-use-case-mobility 6 – IETF SFC interactions with 3GPP PCC architecture IETF 89 - London, UK - 3 March 2014 10 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 ?

11. draft-haeffner-sfc-use-case-mobility 7 – outlook draft-IETF 90 IETF 89 - London, UK - 3 March 201411  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).