[c-nsp] BGP Best Practice

[Danny Vernals]

Thanks,

I'm actually after a good document (RFC, Cisco authored etc) that states
this (ignore my IGP comment but some early BGP-4 RFCs do state that intra-AS
communication is acceptable via redistibution into an IGP, although when
written there were significantly less Internet routes!!! :)).

I know all the theory etc but I need to explain it to a Transit customer of
mine and would like to have an offical document to quote rather than just
explaining it myself.

They currently connect to us via eBGP in 2 geographic locations from one
AS.  I need to stop them from removing the physical and associated iBGP
connectivity between these locations leaving a split-AS.

(They're allowing updates in containing their own AS)


Cheers

Danny

On 6/7/06, Kristian Larsson <kristian at spritelink.se> wrote:
>
> On Wed, Jun 07, 2006 at 11:50:05AM +0100, Danny Vernals wrote:
> > Hello all,
> >
> > Does anyone know of a good document that sets out BGP best practice for
> > Internet useage?
> >
> > I'm specifically looking for something that states policy regarding
> intra-AS
> > routing i.e. that all eBGP speakers must be connected together via iBGP
> or
> > at worst some kind of redistribution into and out of an IGP.
> You will probably be best off using fully meshed
> iBGP. If you redistribute to OSPF and then back
> you will loose all community attributes, lpref and
> so on. Also, if you have some switches not capable
> of a 180k table in OSPF you will not be able to
> use those.
>
> I've actually never heard of anyone redisting an
> entire BGP table into IGP..
> If you have a lot of routers, a route reflector
> might be worth considering.
>
> > I've had a brief scan of RFC1771 and 1772 and can't find anything that
> > states this clearly (although it is hinted at in more than one area)
> >
> > ("*The use of the term Autonomous System here stresses the fact that ?
> the
> > administration of an AS appears to other ASs to have a single coherent
> > interior routing plan and presents a consistent picture of what
> destinations
> > are reachable through it"*  from 1771 is the best I could find)
>
> Regards,
>   Kristian.
>
> --
> Kristian Larsson                                   KLL-RIPE
> IPv6 & Peering coordinator             SpriteLink [AS39525]
> +46 704 910401                       kristian at spritelink.se
>