Re: Multihoming - Resilience or Independence

["Nipper, Arnold" <]

> Read again.  Stephen wrote "SLA on the routing of the address space".
> Global routing of anyone's address space is dependent on the routing
> policies of individual (third-party) ISPs.  Some may be your direct
> peers and you can have agreements with them; many others won't and
> there's no way you can guarantee they'll route your customer's address
> space.  The larger the prefix, the larger the chance of some network
> operator out there filtering it to oblivion.
>

read again: the idea is to put all multi-homing customers in one region into
one prefix (ideally) (MH-pref) and one AS. The prefix should be large enough
to guarantee worldwide routing. E.g. for DE you might have three or four of
these clusters (or maybe only one). All ISP supporting this cluster are
announceing this MH-pref. Internally of course you need a higher resolution.
But that's not the problem.

By covering the whole world with these MH-clusters you obtain 100 (maybe
200, maybe 1000) clusters. So BGP tablesize would be something of current
#ISP + 1000 (or even 10000).

Of course there are still a lot of problems. Mainly cashwise as ISP A could
have to route traffic for customer X though he has no contract with customer
X. And of course MH-AS look very messy. But ...


-- Arnold