For readers interested in networking, I note that the SIGCOMM 2009 program is now available.

Also available is Pathlet Routing, our paper with Igor Ganichev, Scott Shenker, and Ion Stoica. Pathlet routing is a new Internet routing architecture which can improve scalability by enabling very small forwarding tables, and can allow senders to choose between multiple paths for improved reliability and path quality. The idea is basically to do source routing over a virtual topology whose nodes are arbitrary virtual nodes (vnodes) and whose links are sequences of vnodes (pathlets). Intuitively, this architecture is highly flexible because vnodes can represent arbitrary granularities, and because pathlets can represent policy constraints on routing while simultaneously enabling a large number of path choices. This is because sources can stitch together pathlets to form an end-to-end route in potentially exponentially many ways.

An interesting property of the design is that it doesn't impose a global requirement on what "style" of routing policy is used, but rather allows multiple styles to coexist. One router could choose to have routes like in today's Internet, with a giant forwarding table specifying only a single allowed route to each destination. And the next router could have a tiny forwarding table that still gives the network owner some control, but provides a high degree of path choice for the senders. I think of this as being very much in the spirit of the principle of designing for variation in outcome advocated by Clark et al. in their Tussle in Cyberspace paper.