Demystifying Threshold Elliptic Curve Digital Signature Algorithm for MultiParty Applications
Résumé
Elliptic Curve Digital Signature Algorithm (ECDSA) is a crucial authentication component of many modern internet and communication systems. It is used in different domains such as cryptocurrency, IoT, e-health, e-banking, e-governance, etc. Due to the spread of open, distributed and collaborative systems brought by the sharing economy, the surge of interest in generating ECDSA in a distributed manner, i.e. Threshold Signature has grown in recent years. Threshold ECDSA based on multiparty computation (MPC) enables two or more entities of a communication system to generate a signature in a distributed manner. Whereas a subset of t + 1 parties of a group of size n can forge a signature. Any subset of t or less cannot. Threshold ECDSA requires considerable expertise. Thus, in this paper, we provide an overview on how to build a threshold ECDSA scheme in a unified structured way and we describe briefly the different cryptographic building boxes required to provide secure communication between participants, in presence of malicious parties. We also review the state of the art of Threshold ECDSA built by the most recent works and we provide a comparison between the most known schemes that assume a dishonest majority. We finally highlight some challenges and open issues.