IMS user equipment, control method thereof, host device, and control method thereof

A method for controlling an IP Multimedia Subsystem (IMS) User Equipment (UE), the method comprising:

• searching, based on Universal Plug and Play (UPnP) technology, a UPnP network for a host device that has a UPnP service configured to provide IMS subscription information and a first encryption key, the first encryption key being shared with an IMS application server (AS) in an IMS network via a Bootstrapping Server Function (BSF);
• establishing a session with the host device discovered by the searching;
• retrieving, from the UPnP service of the host device via the session, the IMS subscription information;
• registering with the IMS network using the IMS subscription information;
• retrieving, from the UPnP service of the host device via the session, the first encryption key by sending identity of the IMS AS to the host device via the session;
• and
• performing encrypted communication with the IMS AS using the first encryption key.

A host device, comprising:

• establishing circuitry configured for establishing a session with an IP Multimedia Subsystem (IMS) User Equipment (UE) based on Universal Plug and Play (UPnP) technology;
• subscription retrieving circuitry configured for retrieving IMS subscription information from a memory;
• subscription sending circuitry configured for sending, based on UPnP technology, the IMS subscription information to the IMS UE via the session;
• identity receiving circuitry configured for receiving, based on UPnP technology, from the IMS UE via the session, identity of an IMS application server (AS) in an IMS network;
• key retrieving circuitry configured for retrieving a first encryption key based on the identity of the IMS AS, the first encryption key being shared with the IMS AS via a Bootstrapping Server Function (BSF);
• and
• key sending circuitry configured) for sending, based on UPnP technology, the first encryption key to the IMS UE via the session.

A method for controlling a host device, comprising:

• establishing a session with an IP Multimedia Subsystem (IMS) User Equipment (UE) based on Universal Plug and Play (UPnP) technology;
• retrieving IMS subscription information from a memory;
• sending, based on UPnP technology, the IMS subscription information to the IMS UE via the session;
• receiving, based on UPnP technology, from the IMS UE via the session, identity of an IMS application server (AS) in an IMS network;
• retrieving a first encryption key based on the identity of the IMS AS, the first encryption key being shared with the IMS AS via a Bootstrapping Server Function (BSF);
• and
• sending, based on UPnP technology, the first encryption key to the IMS UE via the session.