Research And Design Of Drm Interoperable System Based On Proxy-Cryptography

Various achievements had been made in both academic research and application development for Digital Rights Management System. However, as the number of architectural schemes grew bigger, with each scheme adopting increasingly non-migratable and nonvisible wrapping and encrypting mechanism for digital content, it was getting harder for different DRM technical properties to reconcile and interoperate with each other due to their closed, independent and separate nature. DRM interoperability technology then emerged as a key to connect heterogeneous schemes. However, large numbers of rights issuing and content consuming rules and policies for restriction and permission were still in theoretical stage, lacking actual implementation. So this paper proposed an implementable scheme based on proxy re-cryptography, which significantly contributed to the security and maneuverability for rights interoperability and content conversion in proxy.What this paper mainly accomplished include:1) Introduced the basic algorithm of proxy re-encryption, then raised the problem of current algorithm’s disadvantage in proxy designation and conversion counting control, and proposed a solution by adding specific parameters to bilinear exponent to serve for proxy authentication and conversion counting. These parameters are nonvisible in the bilinear variable to secure its confidentiality. This paper finally implemented the algorithm with testing program, to evaluate and compare its performance with the original algorithm and prove that the extra time consumed was within acceptable range.2) Based on the current DRM interoperability basic architectural research, this paper proposed a new interoperable scheme and system design, and also specified the functions and communication protocols of each module and entity in the system. This paper then illustrated the structured design for digital content and license, described the running procedure for contents’ encryption/decryption, packaging and consumption, rights’ application, issuing and conversion, as well as the data exchange and cryptographic process in source device, destination device and interoperability proxy. This paper also described the logic and operation steps of how content and license files are uploaded to, conversed in, and downloaded from the proxy.3) This paper implemented the prototype of the new DRM interoperable system using C++and Java, the prototype includes the rights issuing and content conversion program in rights center and interoperability proxy, as well as the encoding and playing program for content provider and consumer’s end device. The programs invoked various kinds of cryptographic and packaging library to wrap up content and rights and then generate security file. The prototype also contained Web and MFC interfaces for user files’uploading and downloading operation between servers and end devices. This paper finally presented a display of its running process to show user operation and system performance.