SSChain: A full sharding protocol for public blockchain without data migration overhead

Blockchain, known as distributed ledger technology, suffers from the scalability problem. A major approach to overcoming this limitation is using sharding, which divides the network into multiple smaller groups, called shards, these shards can work in parallel on disjoint transactions and maintain disjoint ledgers. Existing sharding-based protocols rely on reshuffling scheme to maintain security, however, since each shard only maintains a disjoint ledger, reshuffling the network will cause huge data migration. In this work, we propose SSChain, a novel non-reshuffling structure that supports both transaction sharding and state sharding. Our empirical evaluations suggest that SSChain can process more than 6,500 TPS in a network of 1,800 nodes without any data migration overhead. (C) 2019 Elsevier B.V. All rights reserved.