The ISDN approach for mobile radio

This paper describes the Pan-European digital mobile communication system, defined by GSM, which is called in the following the 'GSM-System, its basic characteristis and its influence on the implementation strategy. The first part deals with the basic characteristics of the GSM-System, its system elements and the interworking between these elements. Network scenarios explain the overall message flow through the system. The second part highlights strategies for the implementation of system elements. It describes the requirements to be fulfilled by elements like Base Station, Mobile Services Switching Center Visitor and Home Location Register, Authentication Center and Operation and Maintenance Center. The third part deals with strategies for the mobile com munication network architecture and associated network topologies. The questions of overlay network and integration of the GSM-System into the ISDN are treated, as well as the associated interfacing strategies. The fourth part explaines in more detail basic implementation strategiesfor various system elements. Special emphasis is put on how an JSDN exchange will be expanded to provide the additional GSM functionality of a Mobile Services Switching Center (MSC). It will be demonstrated how the Visitor Location Register (VLR) and Equipment Identity Register (EIR) databases may be integrated in the ISDN exchange.