Subject: [bess] draft-rosen-bess-pta-flags

From: Eric C Rosen <[email-masked]>
Date: Wed, 11 Feb 2015 15:27:10 -0500

The PMSI Tunnel attribute defined in RFC6514 contains a "flags" octet. 
RFC 6514 only defines a single one-bit flag, "Leaf Information 
Required".  However, the next revision of 
draft-dolganow-l3vpn-mvpn-expl-track is probably going to specify the 
use of a second bit from the flags octet.  And 
draft-rabadan-bess-evpn-optimized-ir specifies the use of 4 bits from 
the flags octet.  Since this particular octet only contains eight bits, 
it is probably a good idea to have an IANA registry for it, to minimize 
the chance that two different drafts will try to allocate the same bit 
for different purposes.

Thus the trivial draft draft-rosen-bess-pta-flags, which, if progressed 
to RFC, would establish this registry.

Given the small number of possible allocations, the proposed 
registration procedure is "Standards Action", which automatically 
includes the possibility of "early allocation".

It might also be worth thinking about whether the interpretation of the 
flags octet should be dependent on the type of route to which the PMSI 
Tunnel attribute is attached.  However, that complication is not 
currently suggested in the draft.

Comments?

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From: "Rabadan, Jorge (Jorge)" <[email-masked]>
Date: Thu, 12 Feb 2015 02:42:49 +0000

Eric,

Thanks for this. It is very much needed.

About this:

"It might also be worth thinking about whether the interpretation of the
flags octet should be dependent on the type of route to which the PMSI
Tunnel attribute is attached.  However, that complication is not
currently suggested in the draft."

As you say, given the small number of possible allocations I think we
should make the allocation specific to the type of route and Tunnel Type.
This is what we added in draft-rabadan-bess-evpn-optimized-ir:

"The definition of the "Flags" octect is specific to PTAs with Tunnel
Types IR (0x06) and AR (TBD). The use of the described flags for
other Tunnel Types is out of the scope of this document."

Thanks.
Jorge

-----Original Message-----
From: Eric C Rosen <[email-masked]>
Date: Wednesday, February 11, 2015 at 12:27 PM
To: "[email-masked]" <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Subject: [bess] draft-rosen-bess-pta-flags

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From: Jeff Tantsura <[email-masked]>
Date: Thu, 12 Feb 2015 06:18:00 +0000

Very useful, support!

Cheers,
Jeff