Study On Content Security Of Remote Sensing Image In Cloud Computing

With data sharing services for remote sensing image (RSI) and its applications are increasing, the security of remotely sensed data sharing services is attracting more and more attention in an open network environment. With respect to the sensitivity and particularity of RSI, its security requirements are higher level than the common digital media. RSI as a specific digital media, has not only characteristics of digital image, but many distinct characteristics that different from digital image. Therefore, the study of content security of RSI is essential. Remote Sensing Images belong to the typical "big data". Traditional technology has been unable to achieve data sharing and processing of a large scale of RSIs. But advanced Cloud Computing technology can provide these services. Meanwhile, cloud computing platform itself exsits special security issues. Therefore, study on content security of remote sensing image in Cloud Computing becomes a key subject, which solves not noly the security issues of cloud computing, but also the content security of RSI. However, the study of content security of RSI in cloud computing is in the initial stage, the theories and methods are not mature. Thus, this study is very necessary and has the important theoretical significance and practical value.In this paper, we first construct a basic method of a provable secure CEW (Commutative Encryption and Watermarking) based on orthogonal decomposition. On the basis of this method, we propose a scheme combined re-encryption and watermarking so as to solving the security issue of content protection of RSI in cloud computing. Then, based on the characteristics of remote sensing image and further exploration requirements of RSI, we propose a multiple watermarking algorithm for RSI. Finally, we propose a secure data sharing model for remote sensing image in cloud computing. The research consists of four parts as follows.1) A provable secure CEW based on orthogonal decompositionContent security of digital media contains storage security and copyright protection. Encryption and watermarking as main techniques respectively represents storage security and copyright protection. Only a security mechanism that combines encryption and watermarking can provide the comprehensive and effective content protection for digital media. Current CEW schemes have the following defects:lack of applicability, lack of mixture and lack of security. With respect to the security requirements used in the existing multimedia content protection solutions, we propose a provable Secure CEW based on Orthogonal Decomposition (SCEWOD) scheme. By redefining the encryption and watermarking operations and performing security analyses, the security of the SCEWOD scheme is validated. Therefore, SCEWOD will become a great potential method for multimedia content protection applications and provide the solid foundation for further research.2) A scheme combined re-encryption and watermarkingRe-encryption is a promising approach to maintain data confidentiality in a cloud data service. Thus, only a security mechanism that combines re-encryption and watermarking can provide the comprehensive content protection for cloud digital media. First, this paper designs a trusted secure model for cloud data services. On the basis of the model, we introduce a secure re-encryption algorithm based on EIGamal. Thus, we study the theories of seamless integration and operational independence between re-encryption and watermarking. Finally, we propose a combined re-encryption and watermarking scheme for cloud multimedia data, which provides a theoretical basis for studying content protection of RSI in cloud computing.3) A multiple watermarking algorithm for RSIData sharing service of RSI has diverse demands, in many cases, there are multiple copyright protection and authentication requirements. Thus, multiple watermarking scheme of RSI has become a necessary research content. As a specific image, remote sensing image has some common characteristics and itself unique characteristics. Such as further exploration feature, the requirement of security and computing efficiency, and etc. Therefore, first of all, according to the characteristics of the remote sensing image, this paper selects a suitable watermark operating field and a suitable watermark method. Then, on the basis of SCEWOD, we propose an orthogonal decomposition based multiple scheme for remote sensing image.4) Secure content sharing model of remote sensing image in cloud computingAccording to content security requirements of remote sensing image in a cloud environment, this paper propose a data shared model of content security of remote sensing image in a cloud environment. In this model, the user permissions are classified into three levels. In the first level, the users obtain the original remote sensing image. In the second level, the users obtain the watermarked remote sensing image. In the third level, the users obtain remote sensing image with reversible watermarking. Each level permissions has a different application. In the third level, the remote sensing image owner can control the influence degree on RSI by adjusting the embedded information capacity. Meanwhile, the user can apply to obtain the original RSI. To this, on the basis of SCEWOD, we propose an encryption and reversible marking scheme for remote sensing imagery in cloud computing.Finally, conclusions and future research are presented.