【作者】 傅晓彤；

【导师】 肖国镇；

【作者基本信息】 西安电子科技大学 ， 密码学， 2002， 硕士

【摘要】 本文对信息隐匿技术(Steganography)进行了研究。对信息隐匿的基本概念、研究背景与现状进行了介绍；对隐匿技术的常用术语进行了定义，给出了隐匿技术系统的一个具体分类；针对隐匿技术系统的安全性给出了可能存在的一些攻击类型的描述；同时讨论了数字签名技术与信息隐匿技术之间的关联性，即阈下信道技术的研究与发展。最后，作者提出四个改进的安全隐匿技术方案。在描述各方案的同时对它们各自的安全性进行了详细的讨论和证明。本文的主要结果如下：1．基于文献[5]中对普通隐匿技术系统不安全性的证明结果，重新建立隐匿技术方案的模型，不再把安全保证集中于嵌入函数的选取上，而是把它扩展到整个隐匿系统。2．针对秘密钥隐匿技术中通信双方事先约定共享密钥这一假设并不是总可以实现的问题，提出了一个改进的隐匿技术方案，通信双方能够在秘密通信的开始，安全的生成一个双方共享的秘密密钥。3．借助门限方案的思想，提出一类新的安全隐匿技术方案。即使在传输过程中数据有所丢失，只要接收方能够提取到门限方案中要求的最低数目的嵌入信息，仍然能够成功的进行秘密通信。更多还原

【Abstract】 This paper presents some research results in Steganography. The fundamentalconcepts, research background and on going research is introduced; The commonterminology in this field are defined, and classifies different steganography systems;Then the security issue involved in steganography system is further analyzed, and givesexamples of possible attack types. The relationships between digital signaturetechnology and information hiding technology are also discussed, that is, the researchon subliminal channel technology. Finally, four improved steganography schemes havebeen bring forward. Also provided are in-depth discussions of their respective security.The main contributions of this paper are:1.Based on the proofs given in [5], ordinary steganography system is insecure. In thispaper, a new model of steganography scheme is established; the security is not onlyensured by the selection of embedding function, but also in the whole hiding system.2.Observing the problem that the communicating parties aren’t always able to share apredetermined secret key, an improved steganography scheme is brought forward. Inthis technique, at the beginning of the communication, the communicating parties areable to generate a secret key shared only by the two of them.3.Based on the idea of threshold, a new scheme of steganography is discussed. In thisscheme, even some data is lost during the communication, secret communication can bestill succeed if the receiver is able to get enough embedded information (more than thelow limit in the threshold method).更多还原