Patent ID: 8533348
Filing Date: 2013-09-10
Classification: G06F,H04L

Abstract:
1. A computer-readable storage device, comprising computer instructions, which when executed by a processor causes the processor to perform operations comprising: transmitting a first session initiation protocol registration message to an internet protocol multimedia subsystem network; receiving a first acknowledgment from the internet protocol multimedia subsystem network indicating that a communication device has registered with a primary communication resource in the internet protocol multimedia subsystem network; transmitting a second session initiation protocol registration message to the internet protocol multimedia subsystem network, wherein the second session initiation protocol registration message comprises an indicator for registering the communication device with a secondary communication resource in the internet protocol multimedia subsystem network; receiving a second acknowledgment from the internet protocol multimedia subsystem network indicating that the communication device has registered with the secondary communication resource; transmitting a first session initiation protocol origination message to the primary communication resource of the internet protocol multimedia subsystem network to establish a communication session with a second communication device; detecting that the primary communication resource of the internet protocol multimedia subsystem network is unavailable to establish the communication session; and transmitting a second session initiation protocol origination message to the secondary communication resource to establish the communication session with the second communication device, wherein the first session initiation protocol registration message is received by a first proxy call session control function device, wherein the first proxy call session control function device transmits the first session initiation protocol registration message to a first interrogating call session control function device that selects a primary serving call session control function device of the primary communication resource, and wherein the primary serving call session control function device registers the communication device with a primary application server of the primary communication resource.