EIP-0011: Distributed Signatures

[kushti]

This EIP defines how to implement distributed signatures on top of the Ergo Platform and how implementation is done in the reference protocol client.

Motivating Examples

Alice, Bob and Carol have a joint business and need joint control over business funds. They decide that a 2-out-of-3 quorum is enough to spend the joint funds, so that there is no problem if one of them can not sign because of an illness or a vacation. Thus, they store such funds in boxes protected by 2-out-of-3 threshold signature.

Please note that unlike multi-signatures in Bitcoin, threshold signatures in Ergo preserve zero-knowledge. This leads to interesting applications where actual signers must be hidden but the signing ring is not. For example, it could be desirable to show that union paid to a lawyer, but it is better to hide who approved that spending.