Improved Key Management methodology for enhanced Media Security in IMS Networks

The rapid spread of IP-based access technologies as well as the move towards core network convergence with IMS has led to an explosion in multimedia content delivery across packet networks. Although this transition has led to a much wider and richer service experience, there is also increased concern related to media protection and secure delivery of content that is sent over networks in digital form. There are many efforts ongoing to address this area of DRM in a converged world. The Open Mobile Alliance has probably the most comprehensive approach to this with the recent release of the DRM V2.0 pre-release. Enhanced key management is the most powerful introduction in OMA DRM 2.0 which is used in the trust and security model providing authentication both at user equipment and the application server filling in the gaps of DRM 1.0. In our opinion, the current key management needs an enhancement based on the parameters of messaging introduced by IMS. The main drawback is that only the equipment and application server gets authenticated when we can have the user authenticated before using of content, which would also lead to law enforcing when a user illegally transfers the media file to another user. This paper proposes a novel method of enabling an added level of security and media protection by improving the current key management. The use of this methodology on an existing DRM agent and a customized media streaming component is detailed in the paper. The paper lays out the changes in network infrastructure, both on the client as well as server side, required to enable this. It addresses issues of scalability and performance that are required in a mass-deployed service provider based setup, and demonstrates how the proposed solution would not adversely affect these quality parameters.