IS-IS Meeting Minutes - Monday, July 20th, 2015 1520-1720 CDT Chairs: Chris Hopps and Hannes Gredler Scribe: Acee Lindem (acee@cisco.com) - Intro, Adminastriva, Document Status Presenter: Chairs (Christian Hopps, Hannes Gredler) - IS-IS Path Computation and Reservation (IEEE 802.1Qca) Presenter: János Farkas Document: https://datatracker.ietf.org/doc/draft-farkas-isis-pcr/ * See slides. Acee: Any implementations? Janos: Yes - Avaya has implementation and others have prototypes. Chris Hopps: No objections to WG Last Call. - IS-IS Prefix Attributes for Extended IP and IPv6 Reachability Presenter: Les Ginsberg Document: https://datatracker.ietf.org/doc/draft-ginsberg-isis-prefix-attributes/ * See slides - New co-authors. WG last call requested. Chris: Any objections to WG last call? None Chris: Support WG last call: Significant Chris: Take to list but expect last call. Chris: Early allocation of code points done - was extremely easy. Les: we are requesting last call on two documents: draft-ietf-isis-prefix-attributes-01.txt draft-ietf-isis-route-preference-01.txt The latter document hasn't changed in the last two IETFs - but has a dependency on the prefix-attributes draft and has been on hold until the prefix-attributes draft was ready for last call. - Advertising L2 Bundle Member Link Attributes in IS-IS Presenter: Ahmed Bashandy Document: https://tools.ietf.org/html/draft-ginsberg-isis-l2bundles-00 * See slides. Uma Chunduri: Prefer it would be existing Sub-TLV in TLV 22. Les Ginsberg: Information doesn't impact L3 topology. Would bloat TLV 22 significantly. Isolate L3 topology changes from L2 attributes. Ahmed: Agrees with Les. Stephane Litkowski: Why not just use L3 bundles? Ahmed: Would expose the L3 view to all the protocols running on the links - not just IS-IS. Jen Linkova: Loves the draft. Wants to keep L2 bundles rather than L3 bundles. Hannes: Why not run unnumbered on the parallel links? Ahmed: Unnumbered doesn't work on LANs while this does. Less bloating. Acee: Why not limited the identifier to a link identifiers. No IP addresses. Les: Wanted to leave the door open to define an IPv6 address per link. George Swallow: This is useful and we have this already in MPLS. Chris: (in resoponse to eariler assertion early allocation had been done) Early allocation not done yet. - IS-IS Extensions for Segment Routing Presenter: Stefano Previdi Document: https://datatracker.ietf.org/doc/draft-ietf-isis-segment-routing-extensions/ * See slides. Chris Bowers: Does the algorithm 1 allow an LFA policy? Stefano: Algorithm 0 is whatever has been supported by IS-IS forever? LFA always is a different path. Chris: Text not clear. Acee: What do you mean by no local policy for algorithm 1? Stefano: It only applies within scope of IS-IS? Uma: Add clarifying text on changes. Stefano: Will add. Shraddha Hegde: Can you advertise a separate SID for different algorithm? Stefano: Yes - each algorithm can advertise a separate SID. Bruno: What do you mean by right or wrong MS entry? Stefano: How can you choose when there are conflicts? Bruno Decraene: You can pick one without conflict. Needs to be consistent. Peter Psenak: Why can't one use mapping server for prefixes from prefix-aware routers as well? Stefano: Agress this a good idea. Hannes: Impossible to come up with tie breaking scheme? Stefano: Don't have consensus on tie breaker. Chris: Discuss this on list. Stefano: ALL routers in the domain must behave the same with the respect to SID conflicts. - IS-IS Autoconf Document: https://tools.ietf.org/html/draft-liu-isis-auto-conf-01 Presenter: Bing Liu * See slides. Bing: Asks for WG adoption. Chris: Believes it is progressing. Anyone object to adoption. Chris: No objections and some support for adoption. Chris: Do we even want to do authentication? Acee: We have a simple key configuration option for OSPFv3 authentication. This could be reused in this draft. - IS-IS Extensions for Flow Specification Presenter: Jianjie You Document: https://tools.ietf.org/html/draft-you-isis-flowspec-extensions-01 * See slides: Acee: IS-IS is not defined as an IETF PE-CE protocol. Jianjie: Can remove use case. Hannes: Knows of at least one implementation of IS-IS as a PE-CE protocol. Jianjie: Working group adoption? Uma: Remove section on PE-CE protocol. Jianjie: Will remove. Jeff Haas: How do you limit these flow spec to rules in the routing domain? Jianjie: Will need to define. Chris: Take discussion to mailing list. - Advertising Encapsulation Capability Using IS-IS Presenter: Xiaohu Xu Document: https://tools.ietf.org/html/draft-xu-isis-encapsulation-cap/ * See slides: Jianjie: Requests WG Adoption? Hannes: Objections for WG adoption? None. Chris: Support for WG adoption? Considerable amount. - IS-IS LSP lifetime corruption - Problem Statement Presenter: Bruno Decraene Document: https://tools.ietf.org/html/draft-decraene-isis-lsp-lifetime-problem-statement-00 * See slides. Uma: This problem is discussed in the IS-IS KARP analysis. Is there a proposed solution? Bruno: We can talk of solutions. Chris: You must accepted the packet so the neighbor must have been authenticated. Bruno: Could be man-in-the-middle attack where lifetime is modified in authenticated packets since it is not protected. Chris: Someone would need a box physically placed in the network. Les: Security loophole in IGP begs question of how the attacker got in the network in the first place. George Swallow: Corruption can occur without attacker. For example, via gamma rays. Les: Believes the focus is on attacks rather than corruption. Bruno: Corruption is possible. Les: Cypto authentication will catch corruption. Bruno: Can discuss solutions. Chris: Discussion will continue on the list. - IS-IS Point-to-Multipoint Operation Presenter: David Lamparter Document: https://tools.ietf.org/html/draft-lamparter-isis-p2mp-00 * See slides. Acee: Did you consider a hybrid approach with hellos still multicast? Chris: Multicast is VERY unreliable. Want to assure hellos are reliable once adjacency is established. Donald Eastlake: Why not represented as a mesh of P2P links? David: Link is seen as a broadcast network. Donald: IEEE 802 is defining P2P mesh for broadcast networks. David: Need to solve the problem for existing technologies and hardware. Donald: Why not use association? David: Described in draft. Les: Why do you need a new PDU? David: LAN Hellos used for discovery and P2P Hellos for adjacency maintenance. Les: You can use existing P2P hellos, instead of LAN hellos. Chris: Why not? David: Several use cases where we need to use LAN hellos. Les: Worst thing that could happen is that a router is stuck in INIT state. Only need to change destination addresses. Juliusz Chroboczek: How much do multicast hellos cost? Agress that multicast hellos for discovery and for validation of link layer. Les: LSPs and CSPs cannot be multicast due to the possibility of the lack of transitive connectivity. Hannes: In favor of anything that gets rid of psuedo-nodes. Acee: Even though this is a layer 2 problem, IS-IS P2MP is a good alternative in the immediate time frame. - IS-IS over IPv6 Presenter: Christian Franke Document: https://tools.ietf.org/html/draft-franke-isis-over-ipv6-00 * See slides. Les: There was a draft 15 years ago. One of the strengths of IS-IS is that it runs over layer 2. Problems with requiring IPv6 up prior to running IS-IS. 25 years of history says we don't need this. Mikael Abrahamsson: There are devices on which the Layer 2 packet I/O APIs are not accessible or are hard to use. We need this to promote IS-IS implementation. Chris: I believe the pressure for this is coming from a few folks in homenet. Do we technically need this, or is it just to make some folks happy? Hannes: Have you considered interoperability? Christian Franke: Is is configured per circuit. Possible to handle both encapsulations on same link but there are problems. Hannes: What about MTU compatibility? Christian: Could do IPv6 fragmentation. Jen: IS-IS allows blackholing since it doesn't run over IPv6. Chris: Problem addressed with BFD. - IPv6 Source/Destination Routing using IS-IS Presenter: David Lamparter Document: https://tools.ietf.org/html/draft-baker-ipv6-isis-dst-src-routing-03 * See slides. Chris: How many read? David: Now would be the time to read? Chris: Take discussion to the list.