You can trace all or any selection of channels on a trunk. The trace will show events relating to these channels (such as protocol messages), plus traces of all calls associated with these channels, for as long as they are associated.

The trace information for a call which is associated with a trunk channel will show the same information as a call traced from the Call Details screen. In other words, it will show changes of state for that call, plus events relating to both ends of the call.

In some territories, the central office can hold calls. In such cases, the call is no longer associated with a particular channel. When un-held, it may become associated with the same or a different channel. If such a call is initially associated with a traced trunk channel, it continues in the trace, even if re-associated with a different channel or associated with no channel.