24 Aug Detecting if SIP ALG is Active
A SIP ALG can and usually does exist on Routers, Modems or in rare cases a managed switch.
You must disable this feature for any VoIP service to operate as expected otherwise you may experience:
- Dropped calls
- Loss of voice on one end of the call
Client Based Testing
This link will download a small .exe agent that can test for the presence of a SIP ALG on the network the host PC is connected to.
After downloading, open the file and accept any permissions your windows/mac machine may ask for.
Understanding the results:
- If the results = False then a SIP ALG was not detected by the client.
- If the results = True then a SIP ALG is active and must be turned off.
More information can be found here.