A Security Threshold Subliminal Channel Based on Elliptic Curve Cryptosystem

A subliminal channel can combine with a threshold cryptography to form a new scheme, so that a group of users can share the same subliminal message, and t or more users in the group can cooperatively derive the subliminal message. The existing threshold subliminal channel schemes require users to send their private keys to a message sender. But it is dangerous for users to share their private keys with the message sender in an insecurity environment. To improve this defect, we propose a secure threshold subliminal channel, which is based on elliptic curve cryptosystem. The prominent characteristic of our scheme is that all the users do not need to share their private keys with the message sender. Our scheme not only allows users to share secret information, but also avoids the message sender misusing userspsila private keys to protect userspsila privacies. Thus our scheme can satisfy the security requirements in an insecurity environment.