[70865] in North American Network Operators' Group
RE: Open Source BGP Route Optimization?
daemon@ATHENA.MIT.EDU (Michael Hallgren)
Sat May 29 07:27:04 2004
From: "Michael Hallgren" <m.hallgren@free.fr>
To: <nanog@merit.edu>
Date: Sat, 29 May 2004 13:26:17 +0200
In-Reply-To: <105301c444d9$10ad95a0$fb00a8c0@office.toastedmedia.net>
Errors-To: owner-nanog-outgoing@merit.edu
>
> Per Gregers Bilse <bilse@networksignature.com> wrote:
> > On May 28, 10:37am, "Sam Stickland" <sam_ml@spacething.org> wrote:
> >> Are there any BGP extensions that would cause a BGP
> speaker to foward
> >> all of it's paths, not just it best? I believe quagga had
> made some
> >> recent attempts
> >
> > It has been discussed and been on wish lists, but:
> >
> >> in this direction. IIRC the problem isn't to do with the route
> >> annoucements, it's the route withdrawals. I believe BGP only
> >> specifies the prefix being withdrawn and not the path, so if it's
> >> advertised multiple paths to a prefix it's impossible to
> know which
> >> has been withdrawn.
> >
> > That is 100% correct, yes. Selective withdrawal is not supported.
> >
> > Another issue is that there isn't much point, as far as regular BGP
> > and routing considerations go. Whichever is the best path for a
> > border router is the best path; telling other routers about
> paths it
> > will not use serves no (or at best very little) point in
> this context.
>
> Well something came up recently on a transit router. It takes multiple
> Tier-1 feeds, but management wanted to sell a just MFN to a
> customer. It's possible to policy route all of their traffic
> to the MFN interface and only advertise their prefixes to
> MFN, but not possible to only feed them the MFN routes
> without starting to use VRFs etc.
>
> Of course this is a great perversion of resources ;)
Indeed. Makes me somehow wonder how come that customer did not think
of buying transit directly from MFN? KISS, that is. Or am I missing
something?
mh
>
> Sam
>
>
>
>
