[Idr] Early allocation request for draft-ietf-idr-segment-routing-te-policy

["John G. Scudder" <[e-mail]>]

Hi WG,

Over a month ago we had a request for early allocation of the code points in draft-ietf-idr-segment-routing-te-policy. I think that means the TBD code points listed in section 8.3, the Preference, Binding SID, and Segment List sub-TLVs, since all the rest have been properly allocated by IANA already. The draft appears to fulfill the requirements for early allocation, with one possible exception.

RFC 7120 says 

   c.  The specifications of these code points must be stable; i.e., if
       there is a change, implementations based on the earlier and later
       specifications must be seamlessly interoperable.

On the face of it the current version of the spec fulfills this requirement. I'm slightly concerned that up through draft-previdi-idr-segment-routing-te-policy-02, there were specific values given for 

   o  new sub-TLVs in the registry "BGP Tunnel Encapsulation Attribute
      sub-TLVs":

         Suggested         Description            Reference
            Value
          -----------------------------------------------------
              6           Preference sub-TLV       This document
              7           Binding SID sub-TLV      This document
              8           Segment List sub-TLV     This document

These values conflict with values allocated for other uses in the IANA registry. This was corrected quite some time ago, in -03 published December of 2016, which lists the values as "TBD" just as the current version does, so maybe there's no problem at all. 

I presume that if we proceed forward with early allocation, any pre-standard implementations will be updated to use whatever values IANA actually allocates -- which are sure not to be 6, 7 or 8 since those are already in use. If that's so, then fine. If not, then we may need to have a discussion about whether we really meet the "stability" requirement.

This begins a one-week period for discussion of the early allocation, which time period may be extended if conversation warrants it. For completeness, here's my evaluation of the full list of RFC 7120 criteria:

   a.  The code points must be from a space designated as "RFC
       Required", "IETF Review", or "Standards Action".  Additionally,
       requests for early assignment of code points from a
       "Specification Required" registry are allowed if the
       specification will be published as an RFC.

Yes.

   b.  The format, semantics, processing, and other rules related to
       handling the protocol entities defined by the code points
       (henceforth called "specifications") must be adequately described
       in an Internet-Draft.

Yes.

   c.  The specifications of these code points must be stable; i.e., if
       there is a change, implementations based on the earlier and later
       specifications must be seamlessly interoperable.

Tentatively yes but see above.

   d.  The Working Group chairs and Area Directors (ADs) judge that
       there is sufficient interest in the community for early (pre-RFC)
       implementation and deployment, or that failure to make an early
       allocation might lead to contention for the code point in the
       field.

Yes.

Thanks,

--John