Patent ID: 9538430
Date: 2017-01-03
CPC Classifications: H04W

Claim:
1. A method, comprising: transmitting, by a first station to a second station, an invite to join a voice call on a first radio access network (RAN); receiving, by the second station, the invite; generating, by the second station, a response to the invite; determining, by the second station, that the response cannot be successfully transmitted to the first station; associating, by the second station, with a second RAN; generating, by the second station, a message, for the first station, indicating the second station has associated with the second RAN; transmitting, by the second station, the message to the first station; determining whether the first station is to remain connected to the first RAN to perform the voice call or connect to the second RAN to perform the voice call; connecting to the second RAN when it is determined the voice call is to be performed over the second RAN, wherein the voice call is performed as a VoLTE call by the first station when it is determined the first station is to remain connected to the first RAN; retransmitting, by the first station, the invite to join the voice call; receiving, by the second station, the invite on the second RAN; and setting up the voice call between the first station and the second station.