【作者】 刘晓义；

【导师】 王述洋；

【作者基本信息】 东北林业大学 ， 机械设计及理论， 2010， 博士

【摘要】 参与分布式制造的企业间存在大量的机械工程文件交换,这些文件不仅包括图纸,还包括规范、数控程序、合同,甚至包括软件。目前,企业通常采用廉价、快速的计算机网络进行文件传递,这些机械工程文件普遍涉及专利、商业机密,甚至影响企业的生存安全,需要有效的措施保证其安全传输。目前,面向分布式制造的机械工程文件安全传输技术已经成为分布式制造领域中的一个重要研究课题。本文在黑龙江省科技攻关项目(名称：基于数控设备的数字化,网络化设计与制造系统编号：CC06A129)的支持下,系统地收集并分析了国内外相关的技术文献资料,发现现有面向分布式制造的机械工程文件传输方案,由于没有更多的选择,普遍采用加密的方式进行信息交换。杂乱无章的密文容易引起非法攻击者的注意,暴露通信的机密性,存在严重的安全隐患。为了最大限度地淡化非法攻击者的攻击意识,降低信息被猜测和破译的可能性,本文采取加密技术,结合数字密写技术构建新的传输方案。在加密保护的基础上,由密写技术提供多一层的安全防护,将机械工程文件“伪装”在载体图片中,起到迷惑、欺骗非法攻击者的目的。本文的主要研究内容如下：研究并提出了密写技术结合密码技术的总体方案。确定本系统的实际传输文件为机械工程文件(如：CAD的“.dwg”文件),辅助文件(载体文件)为索引图像和BMP图像。本文研究并提出了最佳效果分配(ORA)密写算法。对比实验表明,该算法在获得比OPA算法更高安全性的同时,获得比OPA改进算法更好的隐藏效果；本文还研究并提出了一种高嵌入量安全BMP图像密写算法。该算法的信息容量大,嵌入过程对图像的直方图影响较小。利用数字图像置乱技术,弥补密写技术无密钥的不足。设计了基于混沌和哈希函数的数字图像置乱算法。算法的时间复杂性较低,满足实际的应用需要。设计面向分布式制造的机械工程文件安全传输系统的构成和操作流程。其中,重点应用本文设计的算法开发了适合分布式制造企业使用的密写软件,成功将机械工程文件隐藏在载体文件中。在黑龙江省机械科学研究院及其合作伙伴间的信息传输实验表明,本系统可以为分布式制造企业提供机械工程文件的传输服务。分布式企业间传递的其它信息(如：对话),如果能够保存成文件,也可以利用本系统进行安全地传输。随着相关技术的深入发展,本方案很有可能成为分布式制造中信息安全传输的必要技术,并扩展新的应用领域。更多还原

【Abstract】 A large number of mechanical engineering files exchange exits between distributed manufacturing enterprises. These files include not only drawings, but also standard, NC program, contracts, and even includes software. At present, the enterprises generally use the inexpensive and fast computer network to carry on the information transmission. Because these manufacture information generally involves patent, commercial secrets, and sometimes is also deciding enterprise’s destiny, an effective measures is needed to guarantee the safety of information transmission. At present, secure transmission of mechanical engineering files facing distributional manufacture has become one of the important research directions in information security transmission domain.This subject is funded by Science-Tech Key Project of Heilongjiang Province(Title: Digital & network design and manufacturing system based on numerical control equipment, ID: CC06A129), and is the result of overall and systematically collected and deeply studied the searched data at home and abroad about information security transfer technology of distributed manufacturing system and digital steganography technology. Found that existing Methods of file transfer program, as the absence of more choices, widely used encryption method to exchange information. Chaotic ciphertext easily lead to attention of unlawful attackers, exposed the confidentiality of communications, has serious security risks.In order to maximize water down the illegal attackers’consciousness, reduce the possibility of speculation and deciphering, this paper has studied and proposed a new method of information security transfer combination the advantages of cryptographic technology and digital steganography technology. On the basis of encryption protection, steganography provides a more layer of security protection, mechanical engineering files can be "disguised" in the carrier image, played a purpose of confused, deceiving illegal attacker. The main results achieved of this paper are as follows:This article identifies the overall program combination of Steganography and Cryptography technology, analysis the selection principles of carries files for Steganography, and take this as the basis, identifies this article’s main research carriers are the index images and the BMP images. As index image, this article designed a new algorithm named optimal result assignment (ORA) algorithm to write secret information into index images. Comparison experiments show that the algorithm can guarantee the security, meanwhile gain a higher image quality than optimal parity assignment (OPA).As BMP images, studied and proposed a high-volume embedded security BMP Image Steganography Algorithm, the algorithm has higher embedding rate, has less affect of the image histogram in the course of embedding, and has higher security.Digital image scrambling technology was used to compensate the lack of non-key steganography technology. A digital image scrambling algorithm is designed based on hash function and chaotic. The algorithm has lower time complexity, high security, to meet the needs of practical application.Developed a steganography software for distributed manufacturing enterprises, achieved ORA, high-density BMP images steganography, scrambling algorithm of Chaos and hash function. After scrambling the carrier of the input file, called ORA or high-volume embedded BMP Image Steganography Algorithm according to the type of input image. Hidden the ciphertext into the scrambled carrier image, and then applied the inverse Scrambling algorithm, gained the carrier images hidden Mechanical engineering files, experiment between Mechanical Sciences in Heilongjiang Province and its partners shows that the system could provide mechanical engineering file transfer service for distributed manufacturing enterprises.Other information (such as:dialogue) passing between distributed enterprises can also be transmitted securely use this system if we can save these information into a file. With the deepening development of relevant technologies, the program is likely to become necessary technology to secure transmission of information for distributed manufacturing, and expand new fields of application.更多还原