Abstract: The present invention relates to a method for transferring a position mark (CO-B0) of a mobile subscriber (B0) in a telecommunications system. The telecommunications system includes a first mobile telephone network (PLMN01) which includes a main switching center (GMSC01) to which a home location register (HLR0) is connected. The telecommunications system also includes a second mobile telephone network (PLMN02) which includes at least one first switching center (MSC-B0). The first switching center includes a visitor location register (GLR-B0) in which the position mark (CO-B0) of the mobile subscriber (B0) is stored. The second mobile telephone network (PLMN02) also includes a main visitor location register (GLR02) which is cognizant of the visitor location register (GLR-B0) of the second mobile telephone network (PLMN02) in which the visiting mobile subscriber (B0) is registered temporarily.

Abstract: A method for handling calls to a terminal in a mobile telephone system of the kind in which the call is handled by an ISUP/IAM message which has a static relationship between the address of the visitor location register in the network in which the terminal roams, and the unique terminal identity. If the visitor location register has no data record relating to the unique identity, an attempt is made to collect from the home location register of the called subscriber the data that is required to complete the connection, this data being stored in the visitor location register. If the attempt is successful and the called subscriber is active, the connection is set up in a known manner with the aid of this data.

Abstract: A method and apparatus for avoiding the use of specially allocated, temporary roaming numbers in a mobile telephone system for routing outside calls to a mobile subscriber roaming in the system. An incoming standardized call signal frame comprising a first parameter field including a directory number is reconstructed. The directory number in the first parameter field is replaced with the unique routing number of the mobile telephone switching center within whose service area the mobile subscriber roams. A unique international mobile subscriber identity and the directory number are inserted in a second parameter field. This implies a static addressing principle in which the routing address will also contain directly the number of the called subscriber. This facilitates restoration of certain registers after a failure.