[83871] in North American Network Operators' Group
Re: Order of ASes in the BGP Path
daemon@ATHENA.MIT.EDU (Tom Sanders)
Mon Aug 29 21:07:21 2005
Date: Tue, 30 Aug 2005 06:30:23 +0530
From: Tom Sanders <toms.sanders@gmail.com>
To: paul@hibernia.jakma.org
Cc: nanog@nanog.org
In-Reply-To: <Pine.LNX.4.63.0508291943200.5384@sheen.jakma.org>
Errors-To: owner-nanog@merit.edu
>=20
> You can *not* merge AS_SET's, as the current BGP specs imply an
> AS_SET has a fixed path-length, hence you should NOT merge the sets
> in:
>=20
> {1 2} [3 4] [5 6]
>=20
> into:
>=20
> {1 2} [3 4 5 6]
>=20
> as the former path has a length of 3, the latter a length of just 2 -
> merging sets could change their meaning. Note though that you're not
> at all likely to see such paths with BGP speakers implementing the
> RFC / draft-ietf-idr-bgp-26.txt draft.
This is one thing that i have always been aware of but dont see it
mentioned in the BGP draft which can be quite confusing to the
newbies. Is it possible to explicitly mention this in
draft-ietf-idr-bgp-26.txt?
Toms.
