Adaptively Secure On-line/Off-line Threshold Signatures

On-line/Off-line threshold signatures are used in a distributed network environment where n entities need to jointly create a signature as soon as possible once the message to be signed is presented. In 2006 and 2007, Crutchfield et al. and Bresson et al. proposed two on-line/off-line threshold signature schemes which are secure only against static adversaries and tolerate up to [n/3] - 1 malicious players. Based on any existing secure threshold signature scheme, we construct an efficient on-line/off-line threshold signature scheme which is adaptively secure and has optimal resilient robustness.