A Dynamic ID-based Authenticated Group Key Agreement Protocol

Abstract

Abstract. Through the group key agreement, all group members could negotiate a common session key which is used in later secure communication. While simple GKA cannot provide enough security to resist the adversary's attack, and the malicious damage during the agreement makes the authenticated key agreement particularly important. In identity-based authentication, user's unique identity information is used as the public key, which makes it exempt from a series of management of the certification in public-key infrastructure. Thereby, the identity-based key agreement can simplify the key management procedures and reduce the risk of failure at the certification authority.Recently, several identity-based group key agreement protocols have been proposed, however most of them are either vulnerable to impersonation and replay attack or inefficient and unscalable. This paper proposes a novel authenticated group key agreement protocol which is based on bilinear pairings. It needs two rounds to negotiate the session key, and the low computational complexity makes the protocol efficient and scalable. Meanwhile, our protocol also ensures the forward and backward secrecy and the key independence. Under the Decisional Diffie-Hellman assumption, our protocol is proved to be secure against the adversary.

A Blockchain-Based Authentication and Dynamic Group Key Agreement Protocol

“…It can be found from Table 2 that our protocol has the lowest computation costs, and the computation costs of our protocol and the protocol of Zheng et al [ 9 ] are very similar. However, from Figure 8 , it can be found that our protocol consumes less communication resources.…”

“…There are many protocols dedicated to reducing the number of authentications between group members by reducing the number of authentication rounds. The group key agreement protocol proposed by Geng et al [ 23 ] and Zheng et al [ 9 ] divides the entire protocol into two rounds. The first round is mutual authentication between members, and the second round is group key generation.…”

“…We compare our protocol with the protocol of Zheng et al [ 9 ], the protocol of Zhang et al [ 21 ], and the protocol of Gupta et al [ 17 ] in terms of computation costs, energy consumption, communication costs, and security.…”

“…In the protocol of Zheng et al [ 9 ], the total computation cost required to generate the group key is , and each group member needs to send messages of length and receive messages of length . In the protocol of Zhang et al [ 21 ], the total computation cost required to generate the group key is , and each group member needs to send messages of length and receive messages of length .…”

“…In recent years, many researchers have proposed many authentication and group key agreement protocols. However, according to the research of [ 7 , 8 ], we found that most of these protocols have the following defects: (1) performance: before the group key is negotiated, mutual authentication is usually required between group members, which may consume much of the computation and communication costs; (2) scalability: the protocol cannot efficiently handle the joining or leaving of group members, which results in the poor scalability of the protocol; (3) forward or backward secrecy: it is difficult to guarantee the forward or backward secrecy of group members after joining or leaving the group, such as [ 9 ]; (4) single node failure: since most existing protocols store the registration information of all group members in a single node, these protocols are vulnerable to the problem of single node failure. Therefore, these protocols are not suitable for MEC.…”