Method and system for providing IMS session continuity to a user equipment across a plurality of communication networks

A non-transitory computer program product for use in a User Equipment and for providing IP Multimedia Subsystem (IMS) session continuity to the UE across a plurality of communication networks, the UE moving from a first communication network to a second communication network, the computer program product comprising a computer readable medium having a computer readable program code embodied therein for performing a method for providing IP Multimedia Subsystem (IMS) session continuity to the User Equipment (UE) across the plurality of communication networks, the method comprising:

• generating, by the computer program product for use in the UE, a complimentary private user identity associated with a public user identity, wherein the public user identity is further associated with a private user identity, and wherein the public user identity and the private user identity are registered by the computer program product for use in the UE with the first communication network using a first address;
• obtaining, by the computer program product for use in the UE, a second address from the second communication network when the UE moves from the first communication network to the second communication network;
• registering, by the computer program product for use in the UE, the public user identity with the first communication network using the second address and the complimentary private user identity;
• and
• registering the public user identity and the private user identity with the first communication network using a third address when the UE moves from the second communication network to a third communication network.

A User Equipment (UE) comprising:

• a receiver capable of receiving at least one address from a plurality of communication networks;
• and
• a processor capable of generating a complimentary private user identity associated with a public user identity, wherein the public user identity is further associated with a private user identity, and wherein the public user identity and the private user identity are registered by the processor with a first communication network using a first address,
• the receiver capable of obtaining a second address from a second communication network when the UE moves from the first communication network to the second communication network,
• a transmitter capable of registering the public user identity with the first communication network using the second address and the complimentary private user identity;
• the receiver capable of obtaining a third address when the UE moves from the second communication network to a third communication network;
• and
• the transmitter capable of registering the public user identity and the private user identity with the first communication network using the third address when the UE moves from the second communication network to the third communication network.