A blockchain based group key agreement protocol (B-GKAP)

Abstract

Group key agreement protocols are crucial in the case of multiple parties agreeing on a common key without a centralized entity. However, the decentralized characteristic of these protocols causes performance challenges where parties need to communicate and verify other participants in the group. To overcome this issue, we propose a new approach to the group key agreement protocols by utilizing Hyperledger Fabric framework as a blockchain platform. To this end, we migrate the communication and verification overhead of the group key agreement participants to the blockchain network in our developed scheme. This paradigm allows a flexible group key agreement protocol that considers resource-constrained entities and trade-offs regarding distributed computation. According to our performance analysis, participants with low computing resources can efficiently utilize our protocol. In addition, the secret parameters of the participants are distributed among the isolated participants that constitute the blockchain network. Thus, the only way for the network participants to compute group keys is to collude maliciously. Furthermore, we have demonstrated that our protocol has the same security features as other comparable protocols in the literature.