Patent ID: 9083723
Filing Date: 2015-07-14
Classification: H04L,H04M

Abstract:
1. A method of a session initiation protocol (SIP) based call connection by a terminating terminal, the method comprising: receiving an invite message containing a first session description protocol (SDP) information on an originating terminal via an application server; transmitting a 180 ringing message containing a second SDP information on the terminating terminal to the application server, prior to transmitting a call response message, wherein the terminating terminal transmits the 180 ringing message after the application server acquires media information for early media and provides the early media to the originating terminal; transmitting the call response message responsive to the invite message to the application server; and establishing a call with the originating terminal, wherein the second SDP information is provided to the originating terminal by the application server before the terminating terminal transmits the call response message.