# Monitoring application scenario

Monitoring applications can also use MSPP channel switching to perform legal intercept of RTP streams, to store messages for later playback, or to log connection activity. This feature can be implemented using RTP forking capability. In the example, RTP OUT1 and RTP OUT2 forward voice data to a monitoring gateway on the IP network.

Step | Action
1 | A gateway application (Fusion gateway 2) receives an incoming call through an RTP IPv4 or IPv6 duplex endpoint (shown as RTP1 in the example).
2 | The gateway places an outgoing call through another RTP IPv4 or IPv6 duplex endpoint (shown as RTP2 in the example).
3 | If the gateway is successful in placing the outbound call, it connects the incoming call (RTP1) with the outgoing call (RTP2) using two simplex RTP switching channels.
4 | The gateway connects the voice data received through RTP1 to an RTP IPv4 or IPv6 simplex send endpoint (shown as RTP OUT1 in the example) using a RTP switching channel.
5 | The gateway connects the voice data received through RTP2 to an RTP IPv4 or IPv6 simplex send endpoint (shown as RTP OUT2 in the example) using a RTP switching channel.