One well-known digital mobile radio system is the Global System For Mobile Communication (GSM). In cellular radio networks like the GSM, a Home Location Register (HLR) stores location and subscriber data for mobile radios registered in the network. When a person subscribes to receive a service from a cellular network operator, the subscription is entered into the HLR of that operator. The location information of moving mobile communications units is periodically updated in the HLR. In addition to the HLR, Visiting Location Registers (VLRs) temporarily store and retrieve location and subscription information for visiting mobile subscribers. Various information (sometimes in considerable amounts) is passed between the HLR and the VLRs, e.g., subscriber's service subscriptions when mobile subscribers are roaming either in a home network or in a visited network.
It is expected that subscription services commonly found with existing satellite and cable television providers will be used with digital broadcasts such as Digital Video Broadcasting (DVB), Advanced Television Systems Committee (ATSC) or Integrated Services Digital Broadcasting (ISDB). However, such subscription services can be fairly complicated to manage. For example, a basic package of channels (as they are called in conventional television services) or services (as they are called in DVB-T) could be without charge, or could be included in a basic subscription. That basic package could also be supplemented with additional services, either singularly or in bundles of services that can be purchased on a pay-per-view basis.
To add to the complication of the subscriptions services, subscriptions typically have a definite duration, or a fixed end time. Therefore, to prevent non-subscribers from receiving a subscription service, it is common to encrypt the services. Subscribers are provided with a key or keys that allow them to decrypt the service for consumption. To allow subscriptions to have a limited duration, the keys are changed at suitable intervals
Additionally, when new services or new subscribers are introduced into a mobile communications system, those new services and/or subscribers are defined in the HLR, and thereafter, the HLR must update the VLRs with the new service and/or subscriber information. Typically, new services are added to the HLR and updated in VLRs. Other types of registers may be used for managing and administrating subscribers. However, the subscriber identification modules (SIMs) used by some mobile devices are typically different for all the operators.
Because all mobile devices agree to get services through an operator, i.e. they are registered users of the operator network/service, there is a need to provide a variety of services to mobile device users. There is a further need to provide the same kind of services offered by operators, but independent of operators. Therefore, it is necessary to provide the users of mobile devices easy and efficient access to content that is broadcast in a network.