ISDSR+: Improving the Security and Availability of Secure Routing Protocol

In ad hoc networks that allow devices to dynamically configure networks via wireless communication, a secure routing protocol is a technology that guarantees the validity of routing with the use of cryptographic authentication. The secure DSR with ID-based sequential aggregate signatures (ISDSR) is a recently introduced secure routing protocol with “cryptographically compact chain,” where each device signs both the routing information and signatures generated by the previous device without increasing the size of signatures and the ID information propagated via packets can be utilized as a public key. However, ISDSR requires communication with a centralized key generation center (KGC), and thus a new device may experience difficulties in joining the protocol. Moreover, the implementation results of ISDSR have not been presented. In this work, we present ISDSR+, a new secure routing protocol without a centralized KGC that uses distributed key generation and the conventional features of ISDSR. ISDSR+ relies on a novel signature scheme where any node can receive a secret key as long as the number of available KGCs is more than a certain threshold. In other words, even if several KGCs are unavailable, the remaining available KGCs can still provide secret keys. We furthermore show promising results of ISDSR+ via a prototype implementation on Raspberry Pis. The results show the computational time of 0.1 s for both the secret key generation and the round trip time (RTT) of routing information under reasonable settings. The RTT of ISDSR+ is better than that of a naive secure routing protocol with RSA signatures.