Scalable group key exchange protocol with provable security

The purpose of this paper is to introduce a scalable group key exchange (GKE) protocol with provable security, which is used to establish a confidential channel.

The protocol in this paper uses line structure, rather than formal ring structure or tree structure, to reduce the amount of calculation and communication.

In the protocol, every participant just need send two messages. The security can be proved under the Decisional Diffie‐Hellman (DDH) problem.

Using the protocol provides an efficient and secure method to allow group users to share a common key.