Patent ID: 9467488
Filing Date: 2016-10-11
CPC Classification: H04L,H04W

Claim Text:
1. A method for initiating a push-to-talk (PTT) call from a caller client device to a recipient client device in a cellular network, said method comprising: registering said caller client device with a PTT over cellular (PoC) server using an enhanced registration request (RRQ) message, wherein said enhanced RRQ message is created by adding a binary session initiation protocol (SIP) invite message in a registration request message; storing at least one data identifying said caller client device at a call session control function (CSCF) in a server, wherein said at least one data includes at least one of a caller client device ID, and caller client device capabilities; initiating a call set up from said caller client device with said recipient client device using said binary SIP invite message; parsing said binary SIP invite message from said enhanced RRQ message at a router in said cellular network; receiving a parsed binary SIP invite message at said CSCF in said server from said router; reconstructing a standard SIP invite message using a received parsed binary SIP invite message and stored data associated with said caller client device at said CSCF in said server; transmitting said standard SIP invite message from said CSCF in said server to said PoC server; and establishing said PTT call between said caller client device and said recipient client device based upon information received in said standard SIP invite message.