Re: Trusting BGP sessions

["Steven M. Bellovin" <smb () research att com>]

In message <20001114202940.19022.cpmta () c004 sfo cp net>, Sean Donelan writes:
> On Mon, 13 November 2000, David Diaz wrote:
> > The cabal makes jokes "Officially there is no cabal."
> > In reality the fact is that peering is a trust event.  You are 
>
> Peering is a business decision.  It is not an engineering decision
> nor a trust event.
>
> Technically, can a peer BGP session do any more or less damage to
> your network than a customer BGP session?  The protocol is identical.

Peer BGP is (often) worse because you can't filter it as aggressively.  
You *know* what prefixes your customers can advertise, and you can 
discard anything else.  But if you have two or more peer sessions, you 
don't in general know which prefixes can legally come from which 
sessions.

                --Steve Bellovin