=============================== Service Function Chaining (SFC) IETF 103 - Bangkok Thursday, November 8, 2018 13:50-15:50 (UTC+07:00) Meeting Minutes =============================== SFC WG chairs: Joel Halpern, Jim Guichard SFC secretary: Tal Mizrahi Meeting minutes: Tal Mizrahi Chair Slides ------------ Presenter: Joel Halpern Slides: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-sfc-chairs-slides-00 Summary: - Note well applies. - The agenda for the current session was presented. - WG progress was presented. - RFC 8459 was published. - The multi-layer OAM document was adopted. That work needs to be aligned with the OAM framework. NSH Encapsulation for In-situ OAM Data (Frank Brockners) -------------------------------------------------------- Drafts: https://tools.ietf.org/html/draft-ietf-sfc-ioam-nsh-00 https://tools.ietf.org/html/draft-ietf-sfc-proof-of-transit-01 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-nsh-encapsulation-for-in-situ-oam-data-00 Summary: - IOAM over NSH: the draft is pretty stable. - Looking for any last comments before requesting WG LC. - Proof of transit: draft changed based on discussion in IETF 102. Now includes in-order preservation. - We have the SSSS with order preservation, and we have the HMAC. There is a question of whether we should have both, or define only one. - We will take it to the list. Discussion: - Greg mirsky: no point in having both options. - Kent liang: what is the value of being in order. This will help understand what we want. Home much value is there in option 2? - Frank: with SSSS (Shamir's Secret) you are not forced to do the order-preservation trick. In some cases we do not need order preservation, and can save the trouble. - Joel: if it is not expensive, you can receive order preservation. Active OAM for Service Function Chains in Networks (Greg Mirsky) ---------------------------------------------------------------- Draft: https://tools.ietf.org/html/draft-wang-sfc-multi-layer-oam-12 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-active-oam-for-service-function-chains-in-networks-00 Summary: - The name of the draft has changed, since it was adopted. - An overview of the changes was presented. Discussion: - Adrian Farrel: two scenarios: O-bit is clear and the protocol is OAM, or O-bit is set and protocol is not OAM. Which of these scenarios is an error? - Greg: we need to consider for each case whether we consider this an error or not. - Adrian: I believe the second should be considered an error. - Frank Brockners: if the next protocl tells you that you have OAM, what is the value of setting the O bit or not? - Joel: the way we define it, SFF should not look beyond the network service header. That is what the O bit is for. - Frank: got it. Performance Measurement with Alternate Marking (Greg Mirsky) ------------------------------------------------------------ Draft: https://tools.ietf.org/html/draft-mirsky-sfc-pmamm-06 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-performance-measurement-with-alternate-marking-00 Summary: - Draft now suggests to use a single marking bit, replacing a bit that is currently not used in the NSH. - Would like to request working group adoption. Hybrid Two-Step Performance Measurement Method (Greg Mirsky) ------------------------------------------------------------ Draft: https://tools.ietf.org/html/draft-mirsky-ippm-hybrid-two-step-02 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-hybrid-two-step-performance-measurement-method-00 Discussion: - Sumandra Majee: follow-up packets - does it mean the packet has to be kept by the devices? - Greg: there can be only one outstanding packet at any given time. - Sumandra: the follow-up must follow the trigger packet immediately? - Greg: you cannot guarantee that it is immediately, but shortly afterwards. Network Service Header (NSH) Explicit Congestion Notification (ECN) Support (Donald Eastlake) --------------------------------------------------------------------------------------------- Draft: https://tools.ietf.org/html/draft-eastlake-sfc-nsh-ecn-support-01 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-network-service-header-nsh-explicit-congestion-notification-ecn-support-00 Summary: - Quick overview, since this was presnted in the last IETF meeting. Discussion: - Jeff Tantsura: I support adoption. - Joel: authors should send an email to the list and request adoption. Geneve applicability for service function chaining (Sami Boutros) ----------------------------------------------------------------- Draft: https://tools.ietf.org/html/draft-boutros-nvo3-geneve-applicability-for-sfc-02 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-geneve-applicability-for-service-function-chaining-00 Summary: - The draft was presented. Discussion: - Kent Liang: you mentioned two options. One of the options was to function as SFF. - Sami: actually NVEs will act as SFF in both options. In a service topology in NVO3 domain. NVE is actually an SFF. NVE is mapped to a service function. Two levels of encapsulation. - Jim: first option you use the NSH header for forwarding decision. Second option - not. - Joel: same tradeoff as always: state is in the device, or state is in the header. From and SFC perspective we do not care how the table gets populated. - Kent: you have hop by hop information. But you don't have to use SPI/SI. - Joel: if the transport has enough information, you can use the transport header to take the forwarding decision. SFC Path OAM (Ting Ao) ---------------------- Drafts: https://tools.ietf.org/html/draft-ao-sfc-oam-return-path-specified-02 https://tools.ietf.org/html/draft-ao-sfc-oam-path-consistency-03 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-sfc-path-oam-00 Summary: - Authors are requesting WG adoption. Discussion: - Joel: send your request to the list. Service Function Chaining: Subscriber and Policy Identification (Dirk Von-Hugo) ------------------------------------------------------------------------------- Draft: https://tools.ietf.org/html/draft-sfc-serviceid-header-01 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-service-function-chaining-subscriber-and-policy-identification-00 Discussion: - Joel: I thank the authors for this significantly improved version of the document. I would like to see more discussion on the mailing list. Name-Based Service Function Forwarder (nSFF) component within SFC framework (Debashish Purkayastha) --------------------------------------------------------------------------------------------------- Draft: https://tools.ietf.org/html/draft-trossen-sfc-name-based-sff-01 Presentation: https://datatracker.ietf.org/meeting/103/materials/slides-103-sfc-name-based-service-function-forwarder-nsff-component-within-sfc-framework-01 Discussion: - Joel: the interaction between nSFF and NR is a new protocol that you are inventing? - Debashish: yes. Adjourned at 15:14.