Re: [Isis-wg] Benoit Claise's No Objection on draft-ietf-isis-sbfd-discriminator-02: (with COMMENT)

["Alvaro Retana (aretana)" <[e-mail]>]

On 11/18/15, 11:05 AM, "Isis-wg on behalf of Les Ginsberg (ginsberg)"
<[e-mail] on behalf of [e-mail]> wrote:

Les:

Hi!

>I do appreciate that people would like an answer to the question of how
>to map multiple discriminators to use cases - but that is not within the
>purview of this document (or its companion OSPF document). We are simply
>defining how to transport an opaque (to the IGP) value. Anything further
>belongs in the base S-BFD document. I think further discussion on this
>point belongs there. (I have made the same statement in regards to the
>same discussion within the context of
>http://datatracker.ietf.org/doc/draft-ietf-ospf-sbfd-discriminator/ .)

I think we're in a situation where we have documents/assumptions pointing
at each other.  While you may be right[*], I think we need to settle
before going forward.

Note that the base S-BFD document reads in Section 3. (Seamless BFD
Overview):

   An S-BFD module on each network node allocates one or more S-BFD
   discriminators for local entities, and creates a reflector BFD
   session.  Allocated S-BFD discriminators may be advertised by
   applications (e.g., OSPF/IS-IS).  Required result is that
   applications, on other network nodes, possess the knowledge of the
   mapping from remote entities to S-BFD discriminators.


This text reads to me that S-BFD is expecting the mapping to be somehow
provided by the "applications (e.g., OSPF/IS-IS)".  There's no other
explicit discussion about the mapping in that document.

Right after sending this e-mail I'm going to put a DISCUSS on this draft
to hold it so we (including the BFD WG, etc.) can answer who is expected
to do what.

Thanks!

Alvaro.


[*] I know the same point was brought up by Acee in the OSPF list, and the
l2tpext draft also takes on the same solution approach.