Joint CIAM and Optimization and Systems Theory Seminar
Tuesday, October 23 2007, 11.00-12.00, Room 3721, Lindstedtsvägen 25

John S. Baras, University of Maryland College Park, USA
Institute for Systems Research
Electrical and Computer Engineering Department and Computer Science Department
University Maryland
College Park, USA

Short bio

Dynamic Iterations on Partially Ordered Semirings with Applications to Trust Evaluation in Networks

Within the realm of network security, we interpret the concept of trust as a relation among entities that participate in various protocols. Trust relations are based on evidence created by the previous interactions of entities within a protocol. In this work, we are focusing on the evaluation of trust evidence in Ad Hoc Networks. Because of the dynamic nature of Ad Hoc Networks, trust evidence may be uncertain and incomplete. Also, no pre-established infrastructure can be assumed. The evaluation process is modeled as a path problem on a directed graph, where nodes represent entities, and edges represent trust relations. We develop a novel formulation of trust computation as linear iterations on ordered semirings. Using the theory of semirings, we analyze several key problems on the performance of trust algorithms. We also analyze the resilience to attacks of the resulting schemes by developing sensitivities of paths to edges and nodes.

Calendar of seminars Last update: October 17, 2007 by Marie Lundin.