Re: The trouble with route announcement updates.

[Nigel Titley <]

> On Tue, 10 Oct 2000, Jacques Caron wrote:
> 
> > - for "smaller" peers (up to a few hundred routes), build strict 
> > prefix-lists based on IRR registrations. Update nightly.
> > - for "larger" peers, build as-path filter-list (in the form "permit _AS$") 
> > based on IRR registrations. Update nightly.
> 
> But does everyone update the IRR? I dont think so. I know many companies
> that dont reg all their routes. 

Well, they don't get routing in our network then. Fairly simple.

In practice it doesn't seem to be too much of a problem, and it helps to keep 
the RR up to date.

> 
> > At 13:55 10/10/00, Neil J. McRae wrote:
> > 
> > >We, at COLT, ourselves use max-prefixes to handle inbound announcements
> > >to our network - we did this because coping with the number of
> > >updates, lack of any notification or process for notification
> > >turned this into a full time job. We have atleast 2 or 3 new
> > >routes every day.
> 
> Exodus also does this. We do filter routes for things we know should not
> be announced to us. Some of them might include EP blocks, RFC1918, etc. We
> also filter some of the larger blocks from peers. IE, we know that other
> providers should not be sending us _701_|_1239_|_3561_|_1_|_etc. But if
> you look, providers are usually leaking one or two routes from these
> larger providers. It is usually a customer of a peer.
> 
> One thing we do is filter all customers. Customers are prefix-list
> filtered. This makes sure that no customer can advertise any route to us
> that we dont know about. 
> 
> So, for peers, we deny larger ASes from the peer and max-prefix the
> peer. For customers, we prifix-list filter so they dont leak anything to
> us we dont know about.
> 
> Christian.
> ----
> Network Architect
> BENGI - Exodus
> AS3967 - NA  AS8709 - EU  AS4197 - AP	EXDS
> 
>