Threshold Signatures for Blockchain Systems

Blockchain, introduced as the backbone of the Bitcoin cryptocurrency, is an emerging technology. Abstracting the currency logic away opens Blockchain to endless applications from finance to healthcare and Internet of Things. Asymmetric cryptography and more specifically digital signatures are a key component of the blockchain system. In this work, we introduce threshold signatures for the Hyperledger Fabric, an implementation of a permissioned blockchain system. Threshold signatures enhance the resilience and robustness of the system while preserving the distributed nature of the Blockchain. In particular: (1) we implement two threshold signature schemes, (2) evaluate their performance, (3) discuss their advantages and limitations and (4) introduce a Framework to hide the implementation details and make threshold signatures available to any potential application in Hyperledger Fabric.