两类信息隐匿技术安全性的信息论分析方法

信息隐匿技术是信息安全研究的一个新的领域,它与信息加密有着显著的区别.数字签名中阈下信道是一种传送隐匿信息的安全信道,但每次传送的信息量很少.阈上信道是新近提出的一种在通信双方未共享任何密钥情况下的安全信道,利用阈上信道可以防止中间人攻击.阈上信息可做为公钥,用于保护后续的隐匿信息的传送.本文利用信息理论对这两类信息隐匿技术的安全性作了分析,得出了确保隐匿信息安全的条件.

Two Sorts of Information Hiding Technique and the Information Theoretic Security Analyses

Information hiding is a new area in the research of information security.It is significantly distinguished from encryption.Subliminal channel existing in some digital signature schemes is a kind of secure channel used for transmitting hidden information.But the information transmitted through this subliminal channel is very limited.Supraliminal channel is a newly presented secure channel used in the case that the receiver and the transmitter share no key ahead of their communication.Supraliminal channel can avoid man in the middle attack.Supraliminal information may be treated as public key for the protection of the subsequent hidden information.Information theoretic analyses are made for the security of the two sorts of information hiding technique.Some security conditions are given.