Copyright © 2006, Idea Group Inc. Copying or distributing in print or electronic forms without written permission of Idea Group Inc. is prohibited. Int’l J. of Business Data Communications and Networking, 2(2), 55-67, April-June 2006 55 Multicast Copyright Protection System Based on a Trusted Soft-Engine Josep Pegueroles, Technical University of Catalonia, Spain Marcel Fernández, Technical University of Catalonia, Spain Francisco Rico-Novella, Technical University of Catalonia, Spain Miguel Soriano, Technical University of Catalonia, Spain ABSTRACT One of the main problems that remains to be solved in pay-per-view Internet services is copyright protection. In Internet services such as near video on-demand, where multicast is used, watermarking can be directly applied. On the other hand, multicast fingerprinting has been seldom studied because delivering different marked content for different receivers seems a contradiction with multicast basics. In this paper we present a solution to prevent unauthorized redistribution of content in multicast scenarios. The system is based on a trusted soft-engine embedded in the receiver and co-managed by the content distributor. The trusted soft-engine is responsible for the client-side multicast key management functions. It only will allow the decryption and displaying of the actual data if it has previously inserted a fingerprinting mark with the identity of the decoder. Keywords: copyright protection; multicast; multimedia distribution services INTRODUCTION The use of multicast is an important handicap when adding fingerprinting mechanisms to commercial content de- livery over the network. In multicast com- munications, all the receivers get the same stream of bits. If any one of the end users illegally redistributes the content, there is no way to distinguish the pirate copy de- livered by the malicious user from the origi- nal one held by honest users. So, unau- thorized redistributors would be masked by the rest of the multicast group. In this sense, copyright protection for multicast arises as a challenging problem in commer- cial network applications. IDEA GROUP PUBLISHING This paper appears in the publication, International Journal of Business Data Communications and Networking, Vol. 2, Issue 2 edited by Jairo Gutierrez © 2006, Idea Group Inc. 701 E. Chocolate Avenue, Suite 200, Hershey PA 17033-1240, USA Tel: 717/533-8845; Fax 717/533-8661; URL-http://www.idea-group.com IT3190