Niels Bakker wrote: > >I have reports that in case (2), some operators (e.g. Rostelecom) > >don't accept the /24 or even /23 prefix on the grounds that it is > >part of a larger /19 route already present in the routing table. > > > >Could they have a reason not to accept these more specific prefixes > >other than a whim? > > If you announce a prefix you must deliver traffic sent to addresses > covered by it. You don't go announcing 0.0.0.0/0 to your peers either. > > If a customer takes a /24 and announces it elsewhere, a transit > provider runs the risk of accepting inbound traffic without having > the possibility to bill their customer for it if it accepts more > specifics from e.g. a peer.
That's all correct from the point of view of the provider annoncing the /19 route, and should be their risk. My question was however from a different perspective. If AS333 receives a /19 from AS111 and a /24 from AS222 (where AS222's /24 is nested within AS111's /19), what reason might AS333 have to ignore the /24? AS333 is not concerned with possible monetary relations between AS111 and AS222. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:[email protected]
