Mema Roussopoulos's research interests span the areas of distributed systems, networking, and mobile and wireless computing. She is particularly interested in learning how to build systems from large numbers of autonomous, unreliable, and mutually distrustful entities that provide, with high probability, specified service levels over long periods of time.

We are actively seeking undergraduate research assistants to work on the LOCKSS project. As the Internet and Web become pervasive, publishers of academic journals are migrating to the Web, forcing the libraries that pay for journals to transition from purchasing copies of the material to renting access to the publisher's web site. Rental provides no guarantee of long-term access, and librarians consider it one of their primary responsibilities to provide future readers with access to important documents. LOCKSS is a peer-to-peer system in which libraries around the world participate to preserve reader access to electronic documents. It consists of independent, low-cost web caches that cooperate to detect and repair damage by voting in "opinion polls" on their cached documents. A key component of the success of such a system is the ability to function despite the presence of very powerful adversaries working to subvert the system.

Potential projects for interested students include exploring the space of attacks an adversary might launch on the system, analyzing the scalability of the system, and studying the feasibility of applying a reputation mechanism to the system. One of the cool things about this project is that you get a chance to work on something that will be deployed and have direct impact at libraries around the world. Students should have strong programming skills in Java and Perl, and ideally should have taken undergraduate courses in operating systems and networking.

If you are interested in applying for an undergraduate research assistant position, please email your cv to me at