A unified approach to a fair document exchange system
This paper aims to propose a solution to unify different approaches to fair document exchange for the development of a flexible, general and secure fair document exchange system capable of guaranteeing strong fairness. The solution caters for a document exchange among any number of parties under various situations. At the heart of this unified solution are methods for a verifiable and recoverable encryption of a symmetric (or conventional) key for document encryption and decryption in a simple and efficient manner. The verifiability means that any party can verify the correctness of a key encrypted without actually viewing the key, and the recoverability implies that the party can be assured that a designated party or a group of designated parties can decrypt the encrypted key to recover the original key. These methods are essential for the unified solution to achieve strong fairness. The main novel contribution of the work presented in this paper is that the proposed unified solution represents the first effort on providing an efficient and unified approach to achieving strong fairness in document exchange under various situations.
fair document exchange telecommunications systems software systems e-commerce