Re: multi-homing fixes

[Iljitsch van Beijnum <iljitsch () muada com>]

On Fri, 31 Aug 2001, Alex Bligh wrote:

> The trouble with using 1 bit to represent 1 prefix is that there is
> a need to move more than 1 bit of information per route between
> AS's (think AS paths for loop detection, communities etc.).

I think it is possible to aggregate this information for a relatively
large number of destinations. That means multihomers wouldn't be able to
set communities for their routes, but at least they'd be reachable and
that has to count for something.

> In iBGP the situation is worse as you have more information
> you want to carry (next hop, localpref), but you seem to
> envisage this only to replace eBGP.

I answered a bit too soon. I meant that the full information should be
carried in iBGP on the originating network (and not in transit networks),
but this is not really necessary either, if you use an IGP. (But some
networks use iBGP rather than an IGP to carry customer routes
internally.)