Fall Back Using Mobile Device Assisted Terminating Access Domain Selection

A wireless communications apparatus that performs fall back procedures, comprising:

• means for forwarding to a first mobile device an invitation for a session, the invitation is from a second mobile device and has packet switched bearers for media;
• means for receiving a rejection to the invitation;
• means for temporarily holding the session as a function of the rejection to the invitation by the first mobile device;
• means for obtaining a circuit switched call from the first mobile device;
• means for mapping the circuit switched call to the session;
• and
• means for establishing a communication between the first mobile device and the second mobile device.

A computer program product, comprising:

• a computer-readable medium comprising:
• a first set of codes for causing a computer to forward an initial INVITE towards a first node over a Gm reference point using packet switched media;
• a second set of codes for causing the computer to create a first Session Initiation Protocol (SIP INVITE) request with a Protocol Specific Identification of Destination Network (PSI DN) in a Session Description Protocol (SDP) body;
• a third set of codes for causing the computer to route the first SIP INVITE to the first node;
• a fourth set of codes for causing the computer to receive from the first node an error SIP response that indicates a network relies on Idle mode Signaling Reduction (ISR);
• a fifth set of codes for causing the computer to hold a session associated with the initial INVITE;
• a sixth set of codes for causing the computer to fetch an Internet Protocol Multimedia Private Identity (IMPI) associated to a GRUU inserted in a contact header of a SIP response;
• a seventh set of codes for causing the computer to receive a second SIP INVITE request from a CS domain;
• an eighth set of codes for causing the computer to fetch the IMPI associated with the second SIP INVITE;
• and
• a ninth set of codes for causing the computer to establish the session toward a second node if the IMPI associated with the first SIP INVITE matches the IMPI associated with the second SIP INVITE.

At least one processor configured to perform call termination as a fall back over circuit switched domain, comprising:

• a first module that sends to a first node an invitation for a session received by a second node;
• a second module that receives a rejection of the session and a request to hold the session;
• a third module that detects a circuit switched call from the first node;
• a fourth module that maps the circuit switched call to the session;
• and
• a fifth module that sets up a dialog between the first node and the second node over circuit switched domain bearers and Internet Protocol Multimedia Subsystem (IMS) bearers.

A method for fall back using mobile device assisted terminating access domain selection, comprising:

• receiving an invitation for a session with packet switched bearers for media;
• rejecting the invitation;
• establishing a circuit switched call toward a network entity;
• and
• terminating an incoming communication that is a correlation of the session and the circuit switched call.

A wireless communications apparatus that utilizes fall back procedures, comprising:

• means for receiving an invitation to a session, the invitation is sent by a mobile device and comprises packet switched bearers for media;
• means for rejecting the invitation;
• means for requesting a network entity to hold the session;
• means for establishing a circuit switched call to the network entity;
• and
• means for communicating with the mobile device over the session and the circuit switched call.

A computer program product, comprising:

• a computer-readable medium comprising:
• a first set of codes for causing a computer to receive an invitation for a session with packet switched bearers for media;
• a second set of codes for causing the computer to reject the invitation;
• a third set of codes for causing the computer to establish a circuit switched call toward a network entity;
• and
• a fourth set of codes for causing the computer to process a communication that is a correlation of the session and the circuit switched call.

At least one processor configured to facilitate fall back procedures comprising:

• a first module that receives an invitation to a session, the invitation is sent by a mobile device and comprises packet switched bearers for media;
• a second module that rejects the invitation;
• a third module that requests a network entity to hold the session;
• a fourth module that establishes a circuit switched call to the network entity;
• and
• a fifth module that communicates with the mobile device over the session and the circuit switched call.