Self-organized Security Architecture for MANET

Abstract

An ad hoc Network is a new generation of network offering unrestricted mobility without any underlying infrastructure. In this kind of network, all the nodes share the responsibility of network formation and management. Fundamental characteristics of an ad hoc network, such as open medium, dynamic topology, dynamic cooperation and constrained capabilities lead to vulnerabilities. Unlike wired network, an ad hoc network does not have a clear line of defense, and every node must be prepared for encounters with an adversary. This paper proposes a three-layer security architecture for ad hoc networks, that provides self-organized distributed security, and authenticated, security aware routing. The first layer in the design performs the operation of a certification server such as issuing, renewal and revocation of certificate using the principle of secret sharing and threshold cryptography. Each certificate issued by this layer has a certain period of validity. Nodes should renew their tokens before expiration. Each node also accumulates its credit whenever it renews the token. The second layer provides authenticated and security aware routing using the token issued by the layer 1. Layer 3 consists of a modified version of reverse labeling restriction protocol that effectively handles internal attacks. This model has been simulated and is found to provide security with negligible overhead.