On Fri, 14 Nov 2003, Suresh Ramasubramanian wrote:
Stephen J. Wilcox writes on 11/14/2003 12:54 PM:
Yeah maybe but what about where the RIRs have assigned independent /24 space.. or ISPs have subdelegated the IPs to a multihomed customer, was more thinking about where a bunch of routes originating from a single ASN can be aggregated rather than routing bloat in general. There are numerous such examples of people with eg a /19 announcing 32x /24 etc
So how do you deal with one but not with the other?
I think your confusing my point - they're different questions, legitimate announcement of /24s by multihoming corporates is at least in principal okay. But I do regulary see people announcing consecutive prefixes all originating in the same AS and (from my view) having the same policy. Ok look heres one example, looks like these guys have a /20: Broad Band Networks / ESINET BBNESINET-48 (NET-12-5-48-0-1) 12.5.48.0 - 12.5.55.255 Broad Band Networks / ESINET BROAD-BA16-56 (NET-12-5-56-0-1) 12.5.56.0 - 12.5.59.255 BROAD BAND NETWORK SERVICES BROAD-BA927-60 (NET-12-5-60-0-1) 12.5.60.0 - 12.5.63.255 So why do I see this lot from them? 11 routes where only one would suffice (1100% more than needed for anyone mathematically challenged).. * 12.5.48.0/24 6453 1239 5778 12163 i * 12.5.48.0/21 6453 1239 5778 12163 i * 12.5.49.0/24 6453 1239 5778 12163 i * 12.5.50.0/23 6453 1239 5778 12163 i * 12.5.52.0/24 6453 1239 5778 12163 i * 12.5.54.0/23 6453 1239 5778 12163 i * 12.5.56.0/23 6453 1239 5778 12163 i * 12.5.56.0/22 6453 1239 5778 12163 i * 12.5.58.0/24 6453 1239 5778 12163 i * 12.5.59.0/24 6453 1239 5778 12163 i * 12.5.60.0/22 6453 1239 5778 12163 i I'm sure these arent the worst offenders but they were the first I came across in my sh ip bgp ... So who's job is it to clean this up - I dont think proxy aggregation is a good idea as someone suggested, the only people in a position to fix this are the ISP themselves, their upstreams and their peers. Steve