A conference key broadcasting system using sealed locks

摘要

A conference key is a secret common key among a set of users by which one can encrypt and decrypt messages in order to communicate securely with others. This paper proposes a conference key distribution protocol suitable for broadcast messages in networks. A sealed lock is used to lock the key and is constructed such that only the private keys of legitimate users are matched. Therefore, the sealed lock is then put on the public directory, only legitimate users can open it and reveal the conference key. The construction of a sealed lock is straightforward and the revelation of conference key is simple.