Gossip consensus

Gossip-based consensus protocols have been recently proposed to confront the challenges faced by state machine replication in large geographically distributed systems. It is unclear, however, to which extent consensus and gossip communication fit together. On the one hand, gossip communication has been shown to scale to large settings and efficiently handle participant failures and message losses. On the other hand, gossip may slow down consensus. Moreover, gossip's inherent redundancy may be unnecessary since consensus naturally accounts for participant failures and message losses. This paper investigates the suitability of gossip as a communication building block for consensus. We answer three questions: How much overhead does classic gossip introduce in consensus? Can we design consensus-friendly gossip protocols? Would more efficient gossip protocols still maintain the same reliability properties of classic gossip?