Abstract

In the current Internet, packets are routed according to their destination address only. Source sensitive routing consist in routing packets also considering their source address. This is requiered in some cases in order to route packets correctly. It can also be used to provide alternate paths, leading to better performance. Internal multihomed networks are a good example of both these applications.

Source sensitive routing requires a forwarding table able to match on destination and source address to make its routing decision. This makes it possible for an address to be matched by two different entries such that no one is more specific than the other. In that case, the choice of which entry to use is left to the FIB implementation of the routers, which can lead to inconsistent results on each router, and even to persistent routing loops.

The solution I will present consists in installing additional routing entries in the FIB such that for every address, the set of routing entries matching that address has a most specific one. I will also discuss changes in the routing protocol, especially interoperability problems, and show some results obtained with our implementation in the Babel routing protocol.

Bio: see http://www.pps.univ-paris-diderot.fr/~boutier/