Threshold Signature for Privacy-Preserving Blockchain.

Threshold signatures received renewed interest in recent years due to their practical applicability to Blockchain technology. In this article, we propose a novel (n,t)-threshold signature scheme suitable for increasing security and privacy in Blockchain technology. Our scheme allows splitting a Blockchain wallet into multiple devices so that a threshold of them is needed for signing. This increases the security of the transactions, e.g., more devices need to be compromised to recover the key and permits, and the privacy, e.g., the signing is made anonymously on behalf of the group of users sharing the Blockchain wallet. Our experimental results show that the signing algorithm requires less than 10 ms in the cases of 10 devices involved.