« Distinguished Lecture Series on Internet and Grid Computing         Peer to Peer Computing Research: A Fad? Thursday, November 14, 2002 10:30am Coffee  ¤  11:00am-12:00pm  ¤  ACES 2.302 (auditorium) The CHORD Distributed Hash Table Friday, November 15, 2002 10:30am Coffee  ¤  11:00am-12:00pm  ¤  Taylor 3.128 Frans Kaashoek     kaashoek@pdos.lcs.mit.edu Professor, Dept of Electric Engineering & Computer Science, MIT                           .   Abstract    Peer to Peer Computing Research: A Fad? Traditionally distributed systems are architected as central servers serving many clients. Recently a number of Internet applications (such as Naptster, Gnutella, and Freenet) have demonstrated the benefits of a peer-to-peer architecture, in which clients cooperatively provide a service, without relying on central servers. This talk will argue that peer-to-peer systems are also a good architecture for building mission-critical distributed services, because they don't have single points of failure. More specifically, this talk will propose peer-to-peer systems based on distributed hash tables (DHTs). DHTs can be made robust in the face of failures, attacks and unexpectedly high loads. They are scalable, achieving large system sizes without incurring undue overhead. They are self-configuring, automatically incorporating new nodes without manual intervention or oversight. They simplify distributed programming by providing a clean and flexible interface. And, finally, they provide a shared infrastructure simultaneously usable by many applications. We sketch an implementation of a DHT based on the Chord distributed lookup system.   Abstract    The CHORD Distributed Hash Table Distributed hash tables are a popular way of constructing peer-to-peer systems in the acadamic community. This talk discusses how to implement a distributed hash table using Chord, which requires log(N) messages and log(N) state per node to lookup a key (where N is the number of nodes). We present Chord's joining, stabilization, and proximity algorithms. We also present a new variant of Chord, de Bruijn lookup, which requires only constant space per node while still achieving logarithmatic lookup. Experimental results from an implementation confirm some of the theoretical properties. Joint work with: Hari Balakrishnan, Frank Dabek, David Karger, David Liben-Nowell, Robert Morris, Ion Stoica, and Emil Sit.   Biography   Frans Kaashoek is a Professor of Computer Science and Engineering in MIT's Department of Electric Engineering and Computer Science and a member of the MIT Lab for Computer Science. Before joining MIT, he was a student at the Vrije Universiteit in Amsterdam, the Netherlands. He received a Ph.D degree ('92) from the Vrije Universiteit for his thesis Group communication in distributed computer systems, under the guidance of Andy Tanenbaum. Frans's research interest is computer systems: operating systems, networking, programming languages, compilers, and computer architecture for distributed, mobile, and parallel systems. The home page for the Parallel and Distributed Operating Systems group describes current projects. In January 1993, Frans was appointed as an Assistant Professor in MIT's EECS department. July 1995 he was awarded the Jamieson Career Development chair. July 1996 he was promoted to Associate Professor. July 1998 Frans received tenure. July 2001 he was promoted to Full Professor. In 1998 Frans cofounded Sightpath Inc, which was acquired by Cisco Systems in 2000. He also serves on the board of Mazu Networks Inc. « 11/7-8 Foster 1/30-31/03 Peterson »