Method and systems for receiving incoming service notification for second SIM network using first SIM network

A system in a multi-Subscriber Identity Module (SIM) enabled User Equipment (UE), the system comprising:

• a registering module configured to register the UE with a network of a first SIM;
• an establishing module in communication with the registering module and configured to establish a secure communication tunnel between the UE and the network of the first SIM and to establish a connection between the UE and a network of a second SIM through the secure communication tunnel established between the UE and the network of the first SIM and through one of an evolved Packet Data Gateway (ePDG) and a Non-3GPP Inter-Working Function (N3IWF);
• the registering module in communication with the establishing module, and further configured to register the UE with the network of the second SIM over the connection established between the UE and the network of the second SIM;
• and
• a receiving module in communication with the establishing module and the registering module, and configured to receive a message indicating downlink data pending at the network of the second SIM, over the secure communication tunnel between the UE and the network of the first SIM.

A multi-Subscriber Identity Module (SIM) enabled User Equipment (UE), the UE comprising:

• a first stack configured to accommodate a first SIM;
• a second stack configured to accommodate a second SIM;
• and
• a system in communication with the first SIM and the second SIM, and the system is configured to:
• register the UE with a network of the first SIM;
• establish a secure communication tunnel between the UE and the network of the first SIM;
• establish a connection between the UE and a network of the second SIM through the secure communication tunnel established between the UE and the network of the first SIM and through one of an evolved Packet Data Gateway (ePDG) and a Non-3GPP Inter-Working Function (N3IWF);
• register the UE with the network of the second SIM over the connection established between the UE and the network of the second SIM;
• and
• receive a message indicating downlink data pending at the network of the second SIM, over the secure communication tunnel between the UE and the network of the first SIM.