Title: Attacking Kad NetworkSpeaker: Yongdae Kim, Assistant Professor, University of MinnesotaDate: Wednesday August 22, 4:00pm~5:30pm 2007Place: ICP Lecture Room (Science Library Buiding 6F)Abstract: In this talk, we discuss security of a popular loosely-coupled P2P network, called Kad network, which has over 1.5 million concurrent nodes. By exploiting critical implementation weaknesses, we developed an attack on Kad that prevents completion of a significant fraction of all Kad keyword searches with reasonable costs &#8211 a single node with a 100Mbps link could stop 65% of all Kad searches. To my knowledge, this is the first experimental (and surprisingly small) estimation of cost for denial-of-service attack on a live P2P network. Experimental results show that this attack is effective against eMule and aMule (eDonkey Network), the most popular Kad clients. Other consequences of these weaknesses include low-cost disruption of targeted keyword searches and the use of the Kad network to mount distributed denial of service attacks.If time permits, we will discuss relation between the Kad network and the storm worm(http://www.symantec.com/security_response/writeup.jsp?docid=2007-011917-1403-99),which has been one of the worst spam relaying botnets. In particular, we discuss how to discover bots (infected hosts) using Kad network.Bio:Yongdae Kim is an Assistant Professor in the Department of ComputerScience at the University of Minnesota, Twin Cities. He received Ph.D. degree from USC in May 2002 under the guidance of Dr. Gene Tsudik.Before joining to Univ. of Minnesota, he was a research staff at UCIrvine (2001-2002) and ETRI, Korea (1993-1998). His current researchinterests are security issues for networks and distributed systemssuch as storage systems, P2P systems, sensor networks. Dr. Kimreceived the National Science Foundation CAREER Award in 2005, and U.of Minnesota McKnight Land-grant Professorship in 2006.++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++Yongdae Kim (office phone) 1-612-626-7526Assistant Professor, + University of Minnesota - Twin Citieskyd (at mark) cs.umn.edu, + http://www.cs.umn.edu/~kyd +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++