Jin-Hee Cho & Ananthram Swami , Army Research

Transcript:Jin-Hee Cho & Ananthram Swami , Army Research:
Jin-Hee Cho & Ananthram Swami , Army Research Laboratory Ing-Ray Chen, Virginia Tech A Survey of Trust Management for Mobile Ad Hoc Networks Outline Background Motivation Multidisciplinary Trust Concept Trust, Trustworthiness, and Risk Assessment Trust Properties in MANETs Survey on Trust Management in MANETs Future Research Directions Background Design Challenges in Mobile Ad Hoc Networks: Resource constraints energy, bandwidth, memory, computational power High security vulnerability open medium derived from inherent nature of wireless networks rapidly changing network topology due to node mobility or failure, RF channel conditions decentralized decision making and cooperation (no centralized authority) no clear line of defense Trust: the degree of subjective belief about the behavior of a particular entity. Motivation Trust management is needed in MANETs with the goal of establishing a network with an acceptable level of trust relationships among participating nodes: During network bootstrapping To support coalition operation without predefined trust For authentication for certificates generated by other parties when links are down To ensuring safety when entering a new zone Diverse applicability as a decision making mechanism for: Intrusion detection Key management Access control Authentication Secure routing Many others Trust in Communications & Networking Trust in Communications & Networking A set of relations among entities participating in a protocol based on evidence generated by the previous interactions of entities within a protocol If the interactions have been faithful to the protocol, then trust will accumulate between these entities Context-aware trust: trust is the quantified belief of a trustor node regarding competence, honesty, security, and dependability of a trustee node in a specific context Trust, Trustworthiness, and Risk Assessment Definition (Trustworthiness): Trustworthiness is objective probability by which the trustee performs a given action on which the welfare of the trustor depends Definition (Trust): Trust is the subjective probability by which the trustor expects that the trustee performs a given action on which the welfare of the trustor depends Definition (Risk): risk is defined by the probability and the consequence of an incident. The risk value is given by the function r : P x C -> RV, where P is a set of trust values in [0,1], C is the set of consequence values and RV is the set of risk values. Trust Level [Solhaug et al., 2007] Trust vs. Risk Trust-based decision making: a trust threshold is used to say yes/no yes when t > trust threshold (t2 in the graph) Risk-based decision