Departmental Papers (CIS)

Date of this Version

August 2005

Document Type

Conference Paper


Postprint version. Copyright ACM, 2005. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in Proceedings of the 2005 Conference on Applications, Technologies, Architectures, and Protocols for Computer Communications SIGCOMM 05, Volume 35, Issue 4, August 2005, pages 289-300.
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NOTE: At the time of publication, author Boon Thau Loo was affiliated with the University of California at Berkeley. Currently (March 2007), he is a faculty member in the Department of Computer and Information Science at the University of Pennsylvania.


The Internet's core routing infrastructure, while arguably robust and efficient, has proven to be difficult to evolve to accommodate the needs of new applications. Prior research on this problem has included new hard-coded routing protocols on the one hand, and fully extensible Active Networks on the other. In this paper, we explore a new point in this design space that aims to strike a better balance between the extensibility and robustness of a routing infrastructure. The basic idea of our solution, which we call declarative routing, is to express routing protocols using a database query language. We show that our query language is a natural fit for routing, and can express a variety of well-known routing protocols in a compact and clean fashion. We discuss the security of our proposal in terms of its computational expressive power and language design. Via simulation, and deployment on PlanetLab, we demonstrate that our system imposes no fundamental limits relative to traditional protocols, is amenable to query optimizations, and can sustain long-lived routes under network churn and congestion.


extensible routing, declarative queries, routing languages



Date Posted: 06 March 2007