Lecture

OpenTor: Anonymity as a Commodity Service

Speaker:	Dr Angelos Stavrou, Columbia University
Date:	Tuesday, 17 July 2007
Time:	12:00-13:30
Location:	"Stelios Orphanoudakis" Seminar Room, FORTH. Heraklion, Crete
Host:	Evangelos Markatos

Abstract:

Despite the growth of the Internet and the increasing concern for privacy of online communications, current deployments of anonymization networks depends on a very small set of nodes that volunteer their bandwidth. We believe that the main reason is not disbelief in their ability to protect anonymity, but rather the practical limitations in bandwidth and latency that stem from limited participation. This limited participation, in turn, is due to a lack of incentives. We propose providing economic incentives, which historically have worked very well. In this talk, we present a payment scheme that can be used to compensate nodes which provide anonymity in Tor, an existing onion routing, anonymizing network. We show that current anonymous payment schemes are not suitable and introduce a hybrid payment system based on a combination of the Peppercoin Micropayment system and a new type of ``one use'' electronic cash. Our system claims to maintain users' anonymity, although payment techniques mentioned previously, when adopted individually,provably fail. This is joint work with Elli Androulaki, Mariana Raykova, and Steven M. Bellovin

Bio:

Angelos Stavrou is currently a Research Assistant at the Network Security Laboratory at Columbia University. His research interests are Security using Peer-to-peer and Overlay Networks, Network Reliability, and Statistical Inference. He received his B.S. in Physics with honors from University of Patras, Greece and an M.Sc. in theory of Algoritms, Logic and computation from University of Athens, Greece. He also holds an M.Sc. in Electrical Engineering from Columbia University and he is currently working toward the Ph.D degree at the same university.

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