OBJECT LOCATION IN UNSTRUCTURED P2P NETWORKS USING RANDOM WALK Nivedita Kailashnath Advisor: Dr. Minseok Kwon MS Seminar October 28, 2008 Rochester Institute of Technology Department of Computer Science Rochester, NY

Outline Problem Statement Overview Existing Solution Proposed Solution Random Walk Approaches Proposed Solution Project Objective October 28, 2008 MS Seminar

Locating file objects efficiently in unstructured P2P networks Problem Statement Locating file objects efficiently in unstructured P2P networks How do you find a file in unstructured P2P network. Flood the network with search message. Issues Network bandwidth gets wasted. Increase in processing overheads of peers. If flooding is not controlled then network will have duplicate packet. Let us consider this maze as an analogy for the problem on hand. Let center of maze be the peer trying to find a file object. And the exit is the peer the which has that file object. Then how do we get out of this maze Image source: http://krazydad.com/mazes/index.php?fmt=CH October 28, 2008 MS Seminar

Existing Solution Random Walk Referenced Variations Each peer selects the next hop peer randomly. Each of the neighboring peers of a peer has equal probability of being selected. Referenced Variations Random walk with reference pointers Biased random walk Directions to exit October 28, 2008 MS Seminar

Random Walk Approaches Biased random walk Random walk with reference pointers October 28, 2008 MS Seminar

Proposed Solution Hypothesis “Biased random walk with reference Pointers” Hypothesis At each hop high capacity nodes will be selected By installing reference pointers at them, chances of find a file object are increased. October 28, 2008 MS Seminar

Project Objective Aim of the project is to verify the correctness of the hypothesis by performing a comparative study of the three approaches and evaluating them against the following metrics: Number of successful and failed search queries Number of hops for finding the file object location October 28, 2008 MS Seminar

References [1] Chawathe, Y., Ratnaswamy, S., Breslau, L., Lanham, N., and Shenker, S. Making Gnutella-like P2P systems scalable. In Proceeding of ACM SIGCOMM'03 (Karlsruhe, Germany, Aug. 2003). [2] Ferriera, R.A., Ramanathan, M.K., Grama, A., and Jagannathan, S. Efficient Randomized Search Algorithms in Unstructured Peer-to-Peer Networks. [3] Gkantsidis, C.,   Mihail, M.  and Saberi, A. Random walks in peer-to-peer networks. In Twenty third Annual  Joint Conference of the IEEE computer and communications Societies, INFOCOMM 2004. October 28, 2008 MS Seminar

Thank You ! October 28, 2008 MS Seminar