IS-IS/OSPF WG Agenda IETF-100 Time Slot (150m): Thursday, November 16, 2017 09:30-12:00 (GMT+8) Scribe: Ayan Banerjee (ayabaner) * Intro, Adminastriva, Document Status o Presenter: IS-IS Chairs and OSPF Chairs (Acee Lindem , Abhay Roy , Christian Hopps , Hannes Gredler ) Discussion of merging WGs: Chris Hopps: Let's discuss merging the two WGs. Acee: Initially against merger but now doesn't feel it is that bad due to advances in OSPFv3 TLV encoding and OSPFv2 prefix/link attributes. Chris Bowers: Thinks having IS-IS and OSPF together will have long-term benefits. Document Status: Chris Bowers: June changes removed ERO and binding SID. Binding SID is needed. Jeff Tantsura: What about OSPF? Alia Atlas: ERO was not specified and didn't relate to SPRING working documents. Behavior and archiecture were not specified. Chris Hopps: Are we aligned? Jeff Tantsura: What is Chris worried about? Chris Hopps: The SR Binding TLV is needed to support context mirroring which is implmented. Jeff Tantsura: Binding SID could be published with use cases. Ketan Talaulikar: Whatever usage of ERO is removed so binding SID could also be removed. Shraddha Hedge: The binding SID TLVs are not implemented right now. There is a use case that could be added in a separate draft. Acee: Usage of Binding SID for context mirroring is sub-optimal. If required, we will define an OSPF Sub-TLV and SID for this purpose. Alia Atlas: OSPFv2 Segment Routing will be sent to the IESG with other SPRING documents. Chris Hopps: Is IS-IS YANG model in sync with OSPF? Acee: Some updates needed - will discuss with co-authors. * OSPF Graceful Restart Enhancements o Presenter: Acee Lindem o Document: https://datatracker.ietf.org/doc/draft-basavaraj-ospf-graceful-restart-enhancements/ Shraddha Hedge: If you generalize the first, you need to handle the case where the peer router is slow forming an adjacency. Acee: Could defer convergence if any neighbors are in Exchange or greater state. * OSPF LLS Extensions for Local Interface ID Advertisement o Presenter: Ketan Jivan Talaulikar o Document: https://datatracker.ietf.org/doc/draft-ietf-ospf-lls-interface-id/ Acee Lindem: Does anybody have any reservations to requesting early IANA allocation for this draft? No objections in the room. * ISIS Segment Routing Flexible Algorithm o Presenter: Shraddha Hedge o Document: https://datatracker.ietf.org/doc/draft-hegdeppsenak-isis-sr-flex-algo/ Chris Hopps: Why are user defined algorithms needed? Shraddha: Constraints cannot be standardized. Dhruv Dhody: PCE has object types for metric types. Maybe metric types in PCE could be used. Ville Hallivuori: One algorithm conflict disable an algorith in the domain? Shraddha: If there is a chance of looping, you must revert to default behavior. Chris Hopps: This a misconfiguration and we don't need to optimize. Bruno: In theory, you need topology ID as well. With SR, we have two algorithms and these cannot be redefined. Shraddha: We don't use standard algorithms for user defined. Metric types are also standardized. Bruno: Standardized algorithm with user defined metric? Shraddha: If you have an algorithm that needs to be standarized, can go to IANA. Ketan: It is possible to define strict SPF with TE metric type. Stephane: This is not an algorithm, it is contraints for SPF. Shraddha: There are Sub-TLVs with contraints. Stephane: Constraints can be independent of algorithms. Shraddha: We will look at decoupling the algorthm and constraint specifications. Chris: MRT algorithms could be defined as standard algorithms. Constraints can be used with standard algorthims. Bruno: Could add standard algorithm field to existing TLVs. Stephane: Maybe could be made flexible by reusing TE objects. Acee: Need to handle case where multi-homed prefix is advertised with different algorithms by different routers. Acee: IPR exists on draft. Dhruv: Please push IPR declaration to the Working Group. * IS-IS TE Attributes per application o Presenter: Acee Lindem for Les Ginsberg o Document: https://datatracker.ietf.org/doc/draft-ietf-isis-te-app/ Chris Bowers: Flex Algorithm should not be referenced since it is not a WG document. Chris Bowers: There are differences between explicit and implicit enablement. * Enablement Discussion Chris Hopps goes through history of draft and his perspective on the adoption of the enablement draft. Chris Hopps: Will discuss enablement in next topic. Chris Hopps: Do we need explicit enablement decoupled from attribute advertisement? Acee: It is dependent on algorithm. For all but TE, it is clear that it is not necessary. Chris Bowers: With both documents WG documents, it is a difficult question. I see need for enablement draft. Solves immediate problem. Alia Atlas: How does enablement related to TEAS and GMPLS? Ketan: Application specific values is a problem that we need to solve. Shraddha: There are sometimes different solutions to the same problem in IETF. Chris Bowers: WG adopted IS-IS TE attributes draft didn't address enablement. Could adopt both drafts. Bruno: Application specific information is theoretical. Stephane: Application specific attributes could be complex. Chris Hopps: It is not that complex that it can't be implmented. Chris Bowers: Could be deployment complexities. Chris Hopps: We are not going to decide this today. Acee: There are much bigger issues in OSPF than IS-IS with the number of LSAs required for non-TE applications. In the case of OSPF, this is more important than how TE enablement is handled. * More Merging Workgroups Chris Hopps: Alia Atlas: Polling of who would only attend OSPF or IS-IS but not both> None Name for New WG: LSR - Link State Routing IGP-LS - IGP - Link State LaSeR - Link State Routing