Abstract
AbstractWe propose a new fair exchange protocol that takes advantage of delay encryption and commutative encryption to achieve optimal partial fairness among all protocols involving one-way messages. Our protocol consists of 3 setup messages and $$2N+1$$
2
N
+
1
exchange messages and it is fair against covert adversaries with probability $$1- \frac{1}{2N}$$
1
-
1
2
N
. We prove that this is optimal up to shortening the setup phase which is notably more efficient than existing protocols.
Publisher
Springer Nature Switzerland