Switchvox - Got a SIP call to <number> from an unknown source explained

The error message you will see in the error log is:

"Got a SIP call to <Number> from an unknown source <IP Address>

The above message means that a random host (IP Address) out there on the internet tried to dial an extension (Number) on the PBX. However, that host is not an authenticated sip provider so the PBX told them to buzz off (play busy). The 'Number' is usually large and looks strange and nothing like an extension so that is just an internet worm looking to exploit some weakness in a PBX.

This message is only in the error log for informational purposes. Where this log might be really useful is if a new SIP provider is not working for some reason. In the past we have seen where a SIP provider will be registered with a hostname / IP and then be sending incoming calls on a different IP. This would lead to the following error messages, and it requires the user to input that IP In the list of known hosts for that provider to accept calls.