The Taub Faculty of Computer Science Events and Talks

The talk will discuss deduplication, a form of compression in which duplicate copies of files are replaced by links to a single copy. Deduplication is known to reduce the space and bandwidth requirements of Cloud storage services by more than 90%, and is most effective when applied across multiple users.

We study the privacy implications of cross-user deduplication. We demonstrate how deduplication can be used as a side channel which reveals information about the contents of files of other users, as a covert channel by which malicious software can communicate with its control center, or as a method to retrieve files about which you have only partial information.

Due to the high savings offered by cross-user deduplication, cloud storage providers are unlikely to stop