Troubleshooting Remote SIP

Troubleshooting Remote SIP Connections

Things to check if a remote phone isn't working.  This can be either no-audio, no call, or intermittent behavior.

If you are troubleshooting a remote phone and you have a network available that you are certain works for registering remote phones to other systems, this network would be a good place to attempt to register the remote phone from.  If it works, then the problem is most likely with the remote router as opposed to the router in front of the PBX.  If it doesn't work then it's an issue with the router in front of the PBX or and ACL issue.

Ensure that

1. External IP or External Host are properly set in PBXSetup->SIP
2. Extension is configured as a WAN phone, (Under advanced in Edit Extension page).
3. ACL under Networking->Access Control->Access Control List make sure that the Remote IP address isn't being blocked.

A great resource for checking the SIP compatibility of a router, as well as instructions for changes that may need to be done on the router such as disabling ALG or SPI.

http://support.vocalocity.com/kb/router-compatibility-guide-and-recommended-equipment-list/