Patent ID: 6856799

Claim:
A communications system, comprising: a multiplicity of mobile devices, to which an identification module is connected in each case, in which identification modules a user identification of the user of the respective mobile device is configured to be stored in each case, at least one visitor location register, to which visitor location register user identifications of the users are configured to be transmitted each by one of the mobile devices and are to be stored there, at least one home location register, in which the user identifications are each configured to be linked to a call number and to further user data comprising location information for a respective user, the location information configured to be transmitted from the visitor location register to the home location register of a user, and connecting modules, by which connecting modules one of the mobile devices in each case is configured to be connectible by a user to a low voltage grid, the connecting modules each comprising a connecting plug configured to connect to the low voltage grid, by which connecting plugs the connecting modules are each configured to be connected to the low voltage grid via outlets of the low voltage grid, and the connecting modules comprising an interface module configured to connect to the respective mobile device, wherein the connecting modules each comprise a power line communications module by which the respective mobile device is configured to communicate via the low voltage grid with other units connected to the low voltage grid via the power line communications module, and wherein at least one visitor location register is connected to at least one low voltage grid by the power line communications module included in the at least one visitor location register, and wherein user identifications are configured to be transmitted to the at least one visitor location register via the low voltage grid by respective mobile devices.