Weighted Voting on the Blockchain: Improving Consensus in Proof of Stake Protocols Proof of Stake (PoS) protocols rely on voting mechanisms to reach consensus on the current state. If an enhanced majority of staking nodes, also called validators, agree on a proposed block, then this block is appended to the blockchain. Yet, these protocols remain vulnerable to faults caused by validators who abstain either accidentally or maliciously.To protect against such faults while retaining the PoS selection and reward allocation schemes, we study weighted voting in validator committees. We formalize the block creation process and introduce validatorsxe2x80x99 voting profiles which we update by a multiplicative weights algorithm relative to validatorsxe2x80x99 voting behavior and aggregate blockchain rewards. Using this framework, we leverage weighted majority voting rules that optimize collective decision making to show, both numerically and analytically, that the consensus mechanism is more robust if validatorsxe2x80x99 votes are appropriately scaled. We raise potential issues and limitations of weighted voting in trustless, decentralized networks and relate our results to the design of current PoS protocols.

ResilientDB: Global Scale Resilient Blockchain Fabric Recent developments in blockchain technology have inspired innovative new designs in distributed resilient database systems. At their core, these database systems typically use Byzantine faulttolerant consensus protocols to maintain a common state across all replicas, even if some replicas are faulty or malicious. Unfortunately, existing consensus protocols are not designed to deal with geoscale deployments in which many replicas spread across a geographically large area participate in consensus. To address this, we present the GeoScale Byzantine FaultTolerant consensus protocol (GeoBFT). GeoBFT is designed for excellent scalability by using a topologicalaware grouping of replicas in local clusters, by introducing parallelization of consensus at the local level, and by minimizing communication between clusters. To validate our vision of highperformance geoscale resilient database systems using GeoBFT, we implement GeoBFT in our efficient ResilientDB blockchain and database fabric. We show that GeoBFT is not only sound and provides great scalability, but also outperforms stateoftheart consensus protocols by a factor of six in geoscale deployments.