A Survey of Group Key Agreement Protocols with Constant Rounds

Abstract

Group key agreement (shorten as GKA) protocol enables a group of users to negotiate a one-time session key and protect the thereafter group-oriented communication with this session key across an unreliable network. The number of communication rounds is one of the main concern for practical applications where the cardinality of group participants involved is considerable. It is critical to have fixed constant rounds in GKA protocols to secure these applications. In light of overwhelming variety and multitude of constant-round GKA protocols, this article surveys these protocols from a series of perspectives to supply better comprehension for researchers and scholars. Concretely, this article captures the state of the art of constant-round GKA protocols by analyzing the design rationale, examining the framework and security model, and evaluating all discussed protocols in terms of efficiency and security properties. In addition, this article discusses the extension of constant-round GKA protocols including dynamic membership updating, password-based, affiliation-hiding, and fault-tolerance. In conclusion, this article also points out a number of interesting future directions.