John M. Brown wrote:
Why should they, there is no reason for them to. Personally I wonder what would happen if we (the rest of us) started filtering on /19's or /20's :)
Not to rehash, but there are legitimate reasons to advertise /24's. I'd say that filtering at that level would be reasonable. What bothers me is seeing certain networks advertising an aggregate along with all or most subnetworks. Being flexible with one's downstreams is one thing, irresponsible adverts are another.
But then you take UUNET (Alternet) and for example 207.170.32.0 /19 is advertised as a /19 AND a stack of /24's all with the same AS path and from what I can tell no special routes, at least not via nitrous.digex.net But what do I know, I am a lonely little guy... :)
My point exactly :-) -- Brian Wallingford Network Operations Manager Meganet Communications, TCIx, Inc.