Re: [Idr] WG LC on draft-ietf-idr-large-community-03.txt (10/17/2016 to 10/31/2016)

[David Farmer <[e-mail]>]

On Mon, Oct 24, 2016 at 12:10 PM, John G. Scudder <[e-mail]> wrote:

> Hi Everybody,
>
> There has been a fair amount of debate about this sentence in the draft:
>
> "   Global Administrator:  A four-octet namespace identifier.  This
>      SHOULD be an Autonomous System Number."
>
> Many of the objections can be summed up by saying "I can't program a
> router to enforce this rule". This is true, but as Brian has pointed out,
> it's hardly the first example of such a thing in a BGP spec. (Indeed, RFC
> 1997 says the equivalent community field "shall be encoded using an
> autonomous system number" but of course provides no enforcement mechanism.)
>
> Other objections seem to be pursuing the question of whether it might be
> possible to revise the proposal to make the rule enforceable. Whether or
> not this is possible in principle seems beside the point since it would
> violate the "small and simple" 1997-equivalent goal of the proposal that
> was part of the consensus when the WG accepted it.
>
> After reviewing the mailing list discussion to date, it's the chairs'
> sense that consensus is trending towards keeping the text as written. As
> always, if you disagree with that consensus and feel you have something new
> to add to the discussion, please do.
>
> Thanks,
>
> --John and Sue
>

I support the consensus as described. However, maybe an alternative to at
least partially address some of the concerns is to discuss the consequences
of the Global Administrator and Local Data Part fields being used
differently than intended. How about something like the following;

   The Global Administrator field SHOULD be an Autonomous System Number
   and is intended to allow different Autonomous Systems to define Large
BGP
   Communities without collision. The meaning associated with the Local
Data
   Part fields are locally defined by each Autonomous System.  Operational
use
   of Large BGP Communities inconstant with this intent could result in
   undesired routing behavior. Implementations MUST allow the operator to
   specify any value for the Global Administrator and Local Data Part
fields.

Thanks.

===============================================
David Farmer               Email:[e-mail]
Networking & Telecommunication Services
Office of Information Technology
University of Minnesota
2218 University Ave SE        Phone: [phone]
Minneapolis, MN 55414-3029   Cell: 612-812-9952
===============================================