In this paper, we propose a new approach for designing distributed systems to survive Internet catastrophes called informed replication, and demonstrate this approach with the design and evaluation of a cooperative backup system called the Phoenix Recovery Service. Informed replication uses a model of correlated failures to exploit software diversity. The key observation that makes our approach both feasible and practical is that Internet catastrophes result from shared vulnerabilities. By replicating a system service on hosts that do not have the same vulnerabilities, an Internet pathogen that exploits a vulnerability is unlikely to cause all replicas to fail. To characterize software diversity in an Internet setting, we measure the software diversity of host operating systems and network services in a large organization. We then use insights from our measurement study to develop and evaluate heuristics for computing replica sets that have a number of attractive features. Our heuristics provide excellent reliability guarantees, result in low degree of replication, limit the storage burden on each host in the system, and lend themselves to a fully distributed implementation. We then present the design and prototype implementation of Phoenix, and evaluate it on the PlanetLab testbed.
The authors of these documents have submitted their reports to this technical report series for the purpose of non-commercial dissemination of scientific work. The reports are copyrighted by the authors, and their existence in electronic format does not imply that the authors have relinquished any rights. You may copy a report for scholarly, non-commercial purposes, such as research or instruction, provided that you agree to respect the author's copyright. For information concerning the use of this document for other than research or instructional purposes, contact the authors. Other information concerning this technical report series can be obtained from the Computer Science and Engineering Department at the University of California at San Diego, firstname.lastname@example.org.
[ Search ]