Ravi Sankar Veerubhotla

A DRM framework towards preventing digital piracy

Digital piracy is a major challenge faced by content publishers and software vendors today. This paper presents a Digital Rights Management (DRM) framework to secure digital content and software applications. The DRM framework uses cryptographic techniques and supports protection of digital content viz., PDF, image and audio files by enforcing user rights such as view, copy, play or print as applicable. The framework is extendable to safeguard libraries of software applications on multiple operating systems. The design offers protection to various file formats with a DRM license that can be upgraded for additional rights or be renewed to get an extended validity. The DRM framework also accommodates offline use of protected content by a one-time (initial) setup and a user license stored locally. Finally, the paper analyzes the design for DRMs crucial requirements like security, flexibility, efficiency and interoperability.

AtDRM : a DRM architecture with rights transfer and revocation capability

This work presents a new Digital Rights Management (DRM) architecture to address rights transfer and revocation aspects of protected content using a threshold Attribute-Based Encryption scheme. We considered two scenarios for rights transfer, here. In first case, a legitimate user needs to consume the protected content on multiple devices, while in second case the user wants to transfer the rights on the content to another user. These scenarios are significant in todays context with the proliferation of smart gadgets and shared cloud services. The architecture is flexible, offers individual or group level access to the protected content and does not require any pre-binding of the devices for consumption. The design inherits this feature from ABE scheme itself and therefore, it is possible to enforce controlled access for individuals as well as groups. Simultaneously, the architecture presents an efficient revocation scheme that eliminates the need of issuing new keys to users or re-encrypting the existing content, either for rights transfer or access revocation. Further, no specific revocation list is to be maintained for revoked users.

On gossip codes and traceability schemes

This work presents a new construction technique for q-ary gossip codes from traceability schemes and vice versa. We demonstrate that these IPP codes, constructed by us, achieve the minimum possible code length specified for gossip codes. Further, we show that these codes can withstand erasures in digital fingerprinting applications and come up with a deterministic tracing algorithm. We also provide construction and analysis for concatenated codes derived from gossip codes.

Reed Solomon Codes for Digital Fingerprinting

Reed Solomon codes are being widely used for error-correcting methods and in construction of fault tolerant systems such as RAID. Recent studies [2], [7], [8] revealed that these codes have a potential application in cryptography. The hardness in decoding Reed Solomon codes can be exposed to construct new cryptographic applications. It is in this scenario that we talk about the suitability of Reed Solomon codes for Digital Fingerprinting in particular and cryptography in general. We derive results for bounds on Fingerprint length, design tracing method for Bonehs broadcast encryption system [2]; and discuss collusion attacks on fingerprint. Pirate strategies and performance issues are also presented.