To use the voice over IP calling protocol, ALERT needs a SIP connection. There are several ways to establish a link with a SIP device, we will connect in this article as a User Agent (A SIP phone).
The current article concerns only ALERT 4.0. For more information about our SIP driver for version 3.6 you can see these FAQs: Voip.
As with a modem, ALERT uses a communication port. Here it will be a SIP port. This SIP port relies on a link with a SIP PBX or a SIP telephony provider.
Configuration require two step:
- Connection setup to the SIP system.
- Creation of the COM port.
Before starting, approach your telephony service to obtain the login ID as well as the SIP service addresses.
Adding a SIP connection
This first step is necessary before adding a port in ALERT.
In the Configuration menu, click on Communication, then the SIP Connections tab.
Then click on 'Add..." to display the SIP connection properties box
SIP tab
Give a name at the connection.
The other parameters to be entered are given by the SIP service provider. Generally for a connection as User Agent, you will need:
- The assigned telephone number. Here "8000".
- The address of the SIP service provider. It's "172.1.xxxxx" above.
- Connection ID (User and password). The user is "alert" in our case.
- Be careful to respect the URI format as in the screenshot above: sip: number@address
Connection tab
The IP Address field allows you to select the network interface to use for SIP communications.
When the setup is validated, if the parameters are correct and the network configuration is OK (SIP port open), a trace in the ALERT event log informs of the registration with the SIP provider (when the option "Register user uri" is checked).
Add a SIP port
Once the connection is correctly configured, you must add a SIP port to be able to make calls.
Select Communication in the Configuration menu or click on the icon in the toolbar.
In the Ports tab click on the button (at the bottom left).
This window will appear:
Select the connection to the SIP service that the new port will use. Here it's "SIP Shoretel"
After confirming with OK, the SIP port properties windows opens:
Specified whether a prefix is necessary to make the calls. (In the case of an installation with a PBX).
The incoming call parameters must be defined if ALERT should answer calls:
- You have to choose the answering driver or "No response".
- You can reserve the port for incoming calls.
- You can add or remove the answering numbers. Or add "*" for all.
Once this information has been validated, if the port is correctly configured, a green LED appears in ALERT:
The ALERT users must be configured with the vocal driver.
Multiple calls
When multiple calls are necessary and if the telephony provider accepts multiple calls, a new SIP port per call should be added as described previously.