The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 15, 2022
Filed:
Nov. 25, 2019
T-mobile Usa, Inc., Bellevue, WA (US);
Sabuhi Kiran Zaifuddin, Bellevue, WA (US);
Shujaur Rehman Mufti, Snoqualmie, WA (US);
Saqib Badar, Bellevue, WA (US);
T-Mobile USA, Inc., Bellevue, WA (US);
Abstract
An Internet Protocol Multimedia Subsystem (IMS) application server can initially attempt to route a terminating call invite to a user equipment (UE) via a packet-switched (PS) domain radio access network (RAN). However, if that initial attempt fails, the application server can follow either a PS retry option to reattempt routing the terminating call invite via a PS-domain RAN, or a circuit-switched (CS) retry option to instead reattempt routing the terminating call invite via a CS-domain RAN. In some examples, if Home Subscriber Server (HSS) data indicates that the UE is connected to a Long-Term Evolution (LTE) RAN and that CS-domain location information for the UE is older than a threshold, the application server can enable the PS retry option. However, if the UE is connected to an LTE RAN but the CS-domain location information is more recent than the threshold, the application server can instead enable the CS retry option.