Survivable key management on WANETs

Key management is an essential service for wireless ad hoc networks. It supports the secure operation of other network services like routing, end-to-end communication, and connectivity that rely on cryptography primitives to create security solutions. Designing key management systems for WANETs is a demanding task due to the self-organization of the network and the lack of a central entity controlling node participation in network services. Furthermore, key management operations should be continuously provided even if the network is partly compromised or experiences failures, attacks, or intrusions. This article gives an overview of existing key management systems for WANETs, highlighting their drawbacks related to survivability. Then it presents SG-PKM, a survivable public key infrastructure for WANETs. SG-PKM uses groups based on users' relationships to increase survivability in the presence of different types of attacks. Finally, it highlights open issues in designing survivable key management systems.