NTP-PoCT: a conformance test tool for push-to-talk over cellular network

Push-to-talk over Cellular (PoC) provides walkie– talkie like service in the cellular telecommunications network [9]. In this service, several predefined PoC group members participate in one PoC session. Since the PoC session is half-duplex, only one group member speaks at a time, and the others listen. Therefore, a user must ask for the permission to speak by pressing the push-to-talk button. In the PoC architecture, the PoC Server (Figure 1 (5)) provides the PoC session handling, media distribution, and talk burst control