Secure Regenerating Codes for Reducing Storage and Bootstrap Costs in Sharded Blockchains
This addresses storage and scalability issues for blockchain miners, but it is incremental as it builds on existing sharding and coding techniques.
The paper tackles the high storage and bootstrapping costs in sharded blockchains by proposing the Secure-Repair-Blockchain (SRB) protocol, which uses exact repair secure regenerating codes to achieve lower storage and bootstrapping costs compared to baselines.
Blockchain is a distributed ledger with wide applications. Due to the increasing storage requirement for blockchains, the computation can be afforded by only a few miners. Sharding has been proposed to scale blockchains so that storage and transaction efficiency of the blockchain improves at the cost of security guarantee. This paper aims to consider a new protocol, Secure-Repair-Blockchain (SRB), which aims to decrease the storage cost at the miners. In addition, SRB also decreases the bootstrapping cost, which allows for new miners to easily join a sharded blockchain. In order to reduce storage, coding-theoretic techniques are used in SRB. In order to decrease the amount of data that is transferred to the new node joining a shard, the concept of exact repair secure regenerating codes is used. The proposed blockchain protocol achieves lower storage than those that do not use coding, and achieves lower bootstrapping cost as compared to the different baselines.