Establishment of an application data channel in an internet protocol multimedia subsystem (IMS) session

Abstract

A method performed by a user equipment (UE) includes sending, toward a terminating UE, a session description protocol (SDP) offer including information about application data channel(s) (ADC(s)) to be established for use by data channel (DC) application(s) within an internet protocol (IP) multimedia subsystem (IMS) session. The method includes receiving, from the terminating UE, an SDP answer including an SDP attribute associated with a DC application of the DC application(s), the SDP attribute including a status of the DC application at the terminating UE. The method includes determining the DC application is not available at the terminating UE based on the status of the DC application indicated by the SDP attribute. And the method includes waiting a time before resending or receiving a new SDP offer including the information about the ADC(s) to be established. FIG. 4