Patent ID: 7577430

Claim:
A method for assigning a mobile communications terminal having a temporary subscriber identity and/or an associated routing parameter to a core network node of a core network provider when changing from a first core network area to a second core network area, the mobile communications terminal having a corresponding radio system that includes a functional unit, comprising: coding of a maximum of, in each case, one core network node of the respective core network area in the routing parameter and/or the temporary subscriber identity of the mobile communications terminal; assigning, by the functional unit, the mobile communications terminal to a core network node of the second core network area, first to the, at most, one core network node of the second core network area which is coded in the routing parameter and/or the temporary subscriber identity, or second to an alternative core network node if, in the second core network area, there is no core network node coded in the routing parameter and/or the temporary subscriber identity, wherein assignment of the mobile communications terminal to the alternative core network is made when the mobile communications terminal is not from a home network of the core network provider.