An Identity-Based Group Key Agreement Protocol for Low-Power Mobile Devices

In wireless mobile networks, group members join and leave the group frequently, a dynamic group key agreement protocol is required to provide a group of users with a shared secret key to achieve cryptographic goal. Most of previous group key agreement protocols for wireless mobile networks are static and employ traditional PKI. This paper presents an ID-based dynamic authenticated group key agreement protocol for wireless mobile networks. In Setup and Join algorithms, the protocol requires two rounds and each low-power node transmits constant size of messages. Furthermore, in Leave algorithm, only one round is required and none of low-power nodes is required to transmit any message, which improves the efficiency of the entire protocol. The protocol's AKE-security with forward secrecy is proved under Decisional bilinear inverse Diffie-Hellman (DBIDH) assumption. It is additionally proved to be contributory.