StakeCube: Combining Sharding and Proof-of-Stake to build Fork-free Secure Permissionless Distributed Ledgers
This addresses scalability and security issues in blockchain systems for decentralized applications, though it appears incremental as it builds on existing sharding and proof-of-stake concepts.
The paper tackles the problem of building a scalable, secure permissionless blockchain by combining sharding and proof-of-stake to prevent forks with negligible probability, using a distributed hash table for randomized shards and verifiable Byzantine agreements.
Our work focuses on the design of a scalable permissionless blockchain in the proof-of-stake setting. In particular, we use a distributed hash table as a building block to set up randomized shards, and then leverage the sharded architecture to validate blocks in an efficient manner. We combine verifiable Byzantine agreements run by shards of stakeholders and a block validation protocol to guarantee that forks occur with negligible probability. We impose induced churn to make shards robust to eclipse attacks, and we rely on the UTXO coin model to guarantee that any stakeholder action is securely verifiable by anyone. Our protocol works against adaptive adversary, and makes no synchrony assumption beyond what is required for the byzantine agreement.