7.1.1 Motivation

One of the driving forces behind recent developments in mobile communications systems is the potential for such systems to deliver more complex content to consumers. Current 3G systems are capable of delivering multimedia clips to subscribers' mobile telephones. The next generation of communications systems are expected to develop this service, and collaborate with broadcast systems to provide wireless access to video content from a wide range of mobile devices. For a service like this to achieve its full commercial potential, the owners of the content will require assurance that their material is not illegally accessed. Current broadcast systems accomplish this by using conditional access systems to ensure that only bona fide subscribers have access to the content.

The Digital Video Broadcasting (DVB) organisation ^[1] has developed several standards for conditional access systems. These standards provide a common interface to conditional access systems at both the transmission site and the receiver, while allowing the systems themselves to remain proprietary. Services broadcast today, therefore, are subject to a range of proprietary access control systems. While receivers remain static, and consumers subscribe to one or two service providers, the DVB standards provide a practical solution.

However, if a mobile subscriber requires access to services controlled by several different conditional access systems, then the current solution becomes increasingly impractical. If future wireless devices are to maximise their access to broadcast services, then a more practical and cost-effective means will be required to allow consumer products...