Two-round contributory group key exchange protocol for wireless network environments

Abstract

With the popularity of group-oriented applications, secure group communication has recently received much attention from cryptographic researchers. A group key exchange (GKE) protocol allows that participants cooperatively establish a group key that is used to encrypt and decrypt transmitted messages. Hence, GKE protocols can be used to provide secure group communication over a public network channel. However, most of the previously proposed GKE protocols deployed in wired networks are not fully suitable for wireless network environments with low-power computing devices. Subsequently, several GKE protocols suitable for mobile or wireless networks have been proposed. In this article, we will propose a more efficient group key exchange protocol with dynamic joining and leaving. Under the decision Diffie-Hellman (DDH), the computation Diffie-Hellman (CDH), and the hash function assumptions, we demonstrate that the proposed protocol is secure against passive attack and provides forward/backward secrecy for dynamic member joining/leaving. As compared with the recently proposed GKE protocols, our protocol provides better performance in terms of computational cost, round number, and communication cost.

An efficient pairing‐free identity‐based authenticated group key agreement protocol

“…As shown in Table , although the AGKA protocols in cannot provide implicit key authentication, each low‐power node needs higher cost of computation than the proposed AGKA protocol. In the AGKA protocols in , each low‐power node requires higher time cost.…”

“…We analyze the performance of the proposed ID-AGKA protocol in terms of the security property and efficiency. We make the security property and performance comparison with the previous AGKA protocols for imbalanced mobile networks [7,10,13,14,11]. The ID-AGKA protocols consist of five phases: setup phase, key extraction phase, key agreement phase, remove phase, and join phase.…”

“…Compared with the key agreement phase, the remove phase or join phase has the time cost in proportion to the changing ratio of node number. So, we only compare the key agreement phase of the AGKA protocols [7,10,13,14,11] in terms of the size of messages sent from each low-power node, the size of message sent by the powerful node, the computation cost of each low-power node, and the computation cost of the powerful node.…”

“…Recently, Wu et al . proposed a more efficient GKA protocol with the dynamic functionality. However, the protocol does not hold implicit key authentication.…”

“…Then again, the GKA protocol of Wu et al . is vulnerable to the ephemeral key compromise attacks. Islam et al .…”