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Thursday March 24th, 2005 - 4:30pm
Computer Laboratory > Research > Systems Research Group > NetOS > Seminars > Thursday March 24th, 2005 - 4:30pm


Tim Griffin

There is a shortage of Internet routing protocols that meet the needs of network engineers. This has led to the Border Gateway Protocol (BGP) being pressed into service as an interior routing protocol, despite the fact that it was designed for exterior routing and that it lacks convergence guarantees. Defining, standardizing, and deploying routing protocols, or even minor changes to existing protocols, is very difficult. I'll present a solution called Metarouting, which is based on the definition of languages that define routing protocols and that can be implemented on routers. Metarouting allows a network operator the freedom to implement and use new routing protocols. The approach is based on three ideas. First, the Routing Algebra framework of Sobrinho [SIGCOMM 2003] is used as the theoretical basis for routing policy languages. Second, we enforce a clean separation of protocol mechanisms (link-state, path-vector, adjacency maintenance, and so on) from routing policy (how routes are described and compared). Third, metarouting employs a Routing Policy Meta-Language (RPML) that allows for the construction of a large family of routing policy languages. I'll present an RPML having the key property that correctness conditions --- guarantees of convergence with respect to the chosen mechanisms --- can be derived automatically for each expression defining a new routing policy language.

This is joint work with Joao Sobrinho (Instituto Superior Tecnico, Portugal)