Patent ID: 7912464

Claim:
A communication system comprising: a mobile device of a first public mobile network, the mobile device including a Subscriber Identity Module (SIM), the SIM having a single International Mobile Subscriber Identity in the first public mobile network (IMSI-H), wherein the first public mobile network has a Home Location Register (HLR) including a single HLR profile corresponding to the IMSI-H; a first Mobile Subscriber Integrated Service Digital Network (MSISDN) number for use in the first public mobile network, the first MSISDN corresponding to the single HLR profile; a second MSISDN number for use in a second public mobile network belonging to a network operator different from that of the first public mobile network, the second MSISDN corresponding to the single HLR profile; and at least one signal gateway routing a first communication between the mobile device and the first public mobile network using the first MSISDN, and routing a second communication between the mobile device and the second public mobile network using the second MSISDN, wherein the at least one signal gateway routes the first and second communications using the single IMSI-H, and wherein the first public mobile network and the second public mobile network have a roaming agreement.