Dynamic Quarantine of Internet Worms
Proceedings of the International Conference on Dependable Systems and Networks (DSN-2004). Palazzo dei Congressi, Florence, Italy. June 28th - July 1, 2004. Supercedes Carnegie Mellon University Parallel Data Lab Technical Report CMU-PDL-03-108, December 2003.
Cynthia Wong, Chenxi Wang, Dawn Song, Stan Bielski, Gregory R. Ganger
Dept. Electrical and Computer Engineering
Carnegie Mellon University
If we limit the contact rate of worm traffic, can we alleviate and ultimately contain Internet worms? This paper sets out to answer this question. Specifically, we are interested in analyzing different deployment strategies of rate control mechanisms and the effect thereof on suppressing the spread of worm code. We use both analytical models and simulation experiments. We find that rate control at individual hosts or edge routers yields a slowdown that is linear in the number of hosts (or routers) with the rate limiting filters. Limiting contact rate at the backbone routers, however, is substantially more effective -- it renders a slowdown comparable to deploying rate limiting filters at every individual host that is covered. This result holds true even when susceptible and infected hosts are patched and immunized dynamically. To provide context for our analysis, we examine real traffic traces obtained from a campus computing network. We observe that rate throttling could be enforced with minimal impact on legitimate communications. Two worms observed in the traces, however, would be significantly slowed down.
KEYWORDS: Internet worms, modeling, worm throttling, rate limiting