Strongly-Resilient and Non-interactiveHierarchical Key-Agreement in MANETs

摘要

Key agreement is a fundamental security functionality bywhich pairs of nodes agree on shared keys to be used for protecting theirpairwise communications. In this work we study key-agreement schemesthat are well-suited for the mobile network environment. Specifically, wedescribe schemes with the following characteristics:Non-interactive: any two nodes can compute a unique shared secretkey without interaction;Identity-based: to compute the shared secret key, each node onlyneeds its own secret key and the identity of its peer;—Hierarchical: the scheme is decentralized through a hierarchy whereintermediate nodes in the hierarchy can derive the secret keys foreach of its children without any limitations or prior knowledge onthe number of such children or their identities;—Resilient: the scheme is fully resilient against compromise of anynumber of leaves in the hierarchy, and of a threshold number ofnodes in each of the upper levels of the hierarchy.Several schemes in the literature have three of these four properties, butthe schemes in this work are the first to possess all four. This makesthem well-suited for environments such as MANETs and tactical net-works which are very dynamic, have significant bandwidth and energyconstraints, and where many nodes are vulnerable to compromise. Weprovide rigorous analysis of the proposed schemes and discuss implemen-tations aspects.