>> Suppose an Internet-connected network consists of site A and site B. >> 10.1.1.0/24 is advertised from and used by site A while 10.1.2.0/24 is >> advertised from and used by site site B. Both sites advertise >> 10.1.0.0/16. Sites A and B are connected to each other, so if site A >> receives a packet for 10.1.2.1, it will forward it to site B. >> >> If site B should lose its internet connection, packets for 10.1.2.1 >> will follow the covering route via site A and still reach site B. >> Regardless of aggregation. > > This has always been true of any form of aggregation --this draft > doesn't introduce any new risk in this area. When you aggregate at any > level, ever, you always introduce the risk of suboptimal routes and/or > routing black holes. Does this mean all routes advertised into the DFZ > should be /24's, or host routes?
BTW, I agree with Alvaro that the draft intends to leave open the option of how to implement this within an individual provider's network, so the provider could choose to check the entire AS Path before bounding a particular route. We had also removed (for simplicity) the "don't bound" community, but we could easily add it back in if providers want the capability to have a customer mark their routes to never be removed. Would that be useful? :-) Russ _______________________________________________ GROW mailing list [email protected] https://www.ietf.org/mailman/listinfo/grow
