Normally SIP Registration starts when Fax Voip FSP Service is started, and then registration is held using regular methods by sending a REGISTER requests in accordance with an Expire Header timeout.
In some environments, registration is not stable. Symptoms may including being able to call in, while other times, you don't get through. This can be caused by a long refresh interval that is too long (see Expire Header parameter), unstable internet connection, some temporary problems on the side of your SIP provider etc. Even if the registration is lost, normally Fax Voip FSP should recover the registration automatically after some time. Nevertheless, in some cases and for various reasons this does not happen and the program remains unregistered. Usually you can fix the problems by changing Expire Header timeout, specifying Outbound Proxy or/and STUN Server options etc.
Unfortunately, in some incompatibility cases, all these efforts can not lead to the desired results.
The options below allow you to fix the problem of unstable SIP Registration regardless of the reasons causing it. Fax Voip FSP periodically sends forcible REGISTER request and restore SIP Registration without having to restart the entire application. These options are configured independently for different SIP Registration entries. Note that this is an auxiliary mechanism. No need to use it if there are no problems with SIP Registration stability.
To configure Restore SIP Registration options
1. Open Fax Voip FSP Control Panel.
2. Click VOIP in TreeView, then click SIP, then click Registrations.
3. Select SIP Registration entry and click Edit (or double-click the selected entry).
4. In the SIP Registration dialog, click <Details> button.
5. Make the necessary settings in the Restore SIP Registration area.
Restore SIP Registrations
Forcibly send REGISTER request every ... min
If this option is checked, Fax Voip FSP periodically sends forcible REGISTER request. The interval between the requests is specified in minutes and can vary from 1 to 999 minutes. Don't specify too small interval if not necessary.
Re-register if only not registered
If this option is checked, Fax Voip FSP does not send the REGISTER request if the current registration status is OK. Otherwise the request is always sent regardless of the current registration status.
Unregister before sending REGISTER request
Check this option to cancel the current registration before re-registering. The real necessity of this command depends on the server, usually not required.
Delay between commands ... sec
The interval between sending unregister and REGISTER commands, in seconds. Can vary from 1 to 10 seconds. 1 second is usually enough. Except the case when the server responds with a big delay.
6. Click <OK> button to fix changes.
7. Click <Apply> button to save modified settings for SIP Registrations. All the changes are applied immediately.