Date Added: Dec 2010
The computational soundness of formal encryption is studied extensively following the work of Abadi and Rogaway. Recent work considers the scenario in which secret sharing is needed, and separately, the scenario when key cycles are present. The novel technique is the use of a co-induction definition of the adversarial knowledge. In this paper, the authors prove a computational soundness theorem of formal encryption in the presence of both key cycles and secret shares at the same time, which is a non-trivial extension of former approaches.