This KB will show you how to perform and analyze a signaling trace in U1981 using LMT tool.
Doing a signaling analyze you can find out and isolate the possible causes of call failure and rectify the fault.
Log in to the unified gateway using the LMT.
Double-click the signaling to monitor (for example, SIP).
Enter the parameters and click Ok.
The signaling information page is displayed.
Make a call, and the system will perform signaling collecting.
Click a signaling in the collecting result.
Use the signaling analysis result to determine the fault cause.
The preceding figure is only an example. You can locate a fault based on the signaling analysis.