Patent ID: 11877193
Assignee: INTEL CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to configure the UE to, execute the instructions to:
for a service request procedure that includes initiation of a service request:
when a T3325 timer is not running:
initiate transmission of the service request to a network and initiate a T3417 timer;
increment a service request attempt counter when a response to the service request has not been received from the network before expiration of the T3417 timer and user data is non-emergency user data; and
initiate the T3325 timer when the service request attempt counter at least meets a predetermined value; and

when the T3325 timer is running and the service request was initiated for a non-emergency multimedia telephony (MMTEL) call:
notify upper layers that the service request was not accepted, and
receive a request from the upper layers to establish a circuit switched (CS) voice call when not already attempted in a CS domain.