Byzantine Consensus Based on Modified Treap Topology

Abstract

In the traditional Byzantine consensus schemes, the efficiency and throughput of the whole topology will be limited by transmission delay in nodes, which depends on the complexity of message and bandwidth constraints. This paper proposes a Byzantine consensus scheme based on weight modified Treap topology that reduces the complexity and delays of message aggregation by quickly constructing and maintaining Treap node tree. We have the master node organize other active nodes into a balanced tree rooted at itself to allocate communication and computing costs. We propose a failure detection mechanism for Treap that makes the master node record the weights of the nodes for each of its direct child nodes. The master node establishes a delay function to set the weight of each node based on the delay between receiving PREPARE message and completing its own calculation to sending its share. With a node's weight over threshold, it is assumed that the node has failed and been marked. The failure detection mechanism of the marked nodes starts to maintain availability by replacing the replication of the marked nodes. It also prevents the parent node from doing evil by authorizing nodes to mark only its direct child node. We only update the Treap topology on a regular basis or in case of failure to reduce the update overhead.