On Mon, 21 Nov 2016, Victor Sudakov wrote:
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.
RIB/FIB bloat. They may figure the least specific route is good enough for getting packets to the destination and assume anything more specific is just the usual pointless deaggregation so commonly seen on the Internet. Maybe they're putting off hardware upgrades required by a current-day unfiltered full table. Maybe there are features that stop working properly on their routers if they load several unfiltered full tables into the RIB. ---------------------------------------------------------------------- Jon Lewis, MCP :) | I route | therefore you are _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________