A secure group communication (SGC) protocol for a P2P group of peers using blockchain

Abstract

In distributed applications, a group of multiple peer processes (peers) are cooperating with one another by exchanging messages in underlying networks. Here, every message sent by each member peer has to be causally delivered to every member peer. In addition to causally delivering messages, each message has to be securely exchanged among peers in a group. That is, each message is required to be sent by only member peers and received by only and every member peer in a group. In one approach to realizing the secure group communication, only and all the member peers share a group key and exchange messages encrypted by the group key. A group key is obtained among member peers by using the PKI (Public Key Infrastructure). However, a CA (Certification Authority) has to provide each peer with a public key of another peer. The blockchain is now used to securely share data among peers by fully replicating append-only data in a distributed manner, especially in a scalable system. In this paper, we propose an SGCB (Secure Group Communication using Blockchain) protocol for member peers in a group to share public keys and create and share a group key by using the blockchain in a distributed manner without using CA.