To add a new SIP trunk, perform the following steps:
The following table describes the trunk parameters under PEER Details. You should obtain the required parameters and values from your service provider and enter them into the PEER Details box.
Parameter | Commonly Used Values | Description |
---|---|---|
host | xxx.xxx.xxx.xxx | IP address of the SIP trunk provider's server |
type | peer |
The supported values are: peer, user, friend. Friend is both a peer and user. |
context | from-trunk |
"from-trunk" means that incoming calls from this trunk will be treated as if they are coming from an outside line, and will be routed using the rules that you setup in the Inbound Routes page. "from-internal" means that incoming calls from this trunk will be treated as if they were made by an internal phone, and will be routed directly to an extension number, a feature code, or through the outbound routes page. "from-pstn-toheader" means that incoming calls from this trunk is from an outside line where the DID number is embedded in the toheader. Generally, you use "from-trunk" when routing calls from an outside source and "from-internal" for trunks that tie two trusted systems together. |
qualify | yes |
"yes" means to periodically send a request that the other system identify itself. If there is no answer within 2 seconds, your system will assume that the other system is down and stop sending calls to the system until the system responds. Instead of "yes," you can also put a number, in miliseconds. For example, qualify=3000 means that your system will wait 3 seconds for a response, instead of 2 seconds. |
insecure | port,invite |
"port" means to accept incoming calls even if they come from a port other than the one where calls are expected to come from. "invite" means to accept incoming calls even if they are not accompanied by the proper username and password. Most ITSP's require this line. If only one is used, the comma separating them is omitted. |
deny | 0.0.0.0/0.0.0.0 | [Optional] For added security, include "deny" and "permit" to limit access based on IP address. |
permit | xxx.xxx.xxx.0/255.255.255.0 | [Optional] Allow access only to the specified IP subnet. |
callbackextension | xxxxxxxxxx | [Optional] DID number associated with the trunk. Add this field if you have more than one SIP trunk from the same SIP provider. |
If you have a dedicated internet connection for your SIP trunk, proceed to the Static Routes page to configure a static route for your SIP trunk.
If you have more than one SIP trunk from the same SIP provider, add the callbackextension=<DID number>
For example, you have two SIP trunks from the same service provider. One trunk is associated with DID number 2144277218 and another is associated with DID number 4697012911. Both trunks are registered to the same provider's server.
For the first trunk, add callbackextension=2144277218 to the PEER Details of the first trunk.
For the second trunk, add callbackextension=4697012911 to the PEER Details of the second trunk.