Key Recovery Schemes Of Protocols Based On Subliminal Channel

With the fast development of Internet and information technology, the application of cryptography technology becomes more widely used. It gets involved with many significant fields like e-Business, e-Government and public facilities etc. The keys in typical encryption technology are far beyond the computation ability today, which ensures the security of key information transmission. But on the other hand, the perfect encryption system also protects the illegal people and activities from the monitor of governments.The key recovery technology was proposed in order to provide method to decrypt the cipher text using acceptable resources and time. The first appearance was the EFS (Escrow Encryption Standard) which was considered as controversial later. In order to balance the benefits and privacy between the government, the companies and the public, EFS standard was replaced by the key encapsulation. The famous implementations included TIS key recovery system and IBM key recovery system.Key recovery system available today use additional field adding after the original protocol data. The field contents the encrypted session key information. The implementation is practical but with obvious disadvantage: the illegal user can easily notice the key recovery, and by data package filtering, the key recovery function can be screened. To avoid this fault, the protocol based key recovery scheme using the subliminal channel was proposed. The general idea is: use the TTP's (Trusted Third Party) public key to encrypt the session key. The field hides into the subliminal channel inside...