公开(公告)号：US20240187458A1

公开(公告)日：2024-06-06

申请号：US18553726

申请日：2021-06-07

Applicant: QUALCOMM Incorporated

Inventor： Shuhong WANG ,  Bing LENG ,  Jing ZHOU ,  Jian LI ,  Xuefeng CHEN ,  Yan WANG ,  Hao ZHANG

IPC: H04L65/1016 ,  H04L65/1069 ,  H04W76/18

CPC classification number: H04L65/1016 ,  H04L65/1069 ,  H04W76/18

Abstract: A method and apparatus improve Voice over Internet Protocol (VOIP) call setup success rate and latency. The method provides for attempting a mobile originated packet switched call, by a user equipment (UE), across a packet switched network with a transmission control protocol (TCP) connection of the Internet Protocol multimedia subsystem (IMS) session. A silent redial of the mobile originated packet switched call is performed in response to a failure of the mobile originated packet switched call, via a circuit switched network. A keep alive message is transmitted over the packet switched network after the circuit switched network call, which allows reconnection to the packet switched network.