International Association
for Cryptologic Research

In this survey, we discuss an emerging concept of decoy-based information security, or security without computational assumptions.

In particular, we show how this concept can be implemented to

provide security against (passive) computationally unbounded adversary in some public-key encryption protocols. In the world of symmetric cryptography, decoy-based security finds a wide range of applications, notably to secure delegation of computation to another party. We single out the scenario where a computationally limited party wants to send an encrypted message to a computationally superior party using the RSA protocol, thereby providing another kind of application of decoy ideas in a public-key setting. With typical RSA parameters, decoy-based method of delegation of computation improves the efficiency for the sender by several orders of magnitude.