User guide

exten => 464,1,Dial(IAX2/464)
exten => 466,1,Dial(IAX2/466)
exten => t,1,Hangup() ; Special extension (Timeout)
exten => i,1,Hangup() ; Special extension (Invalid)
exten => s,1,Hangup() ; Special extension (No routing information)
The syntax of the extensions.conf file is intuitive.
• The brackets [context_name] indicates where the context starts and the name of the context as
it is defined in the sip.conf and iax.conf.
• Each line within a context is an extension with the following format:
exten => number, priority,application-action
In this simple configuration file we are saying that each of the extension numbers 462-466 is reachable
by executing the command Dial and creating a SIP or IAX2 channel to the peers with the same
username.
8. Scenario B - Reaching the PSTN
Our second case study is an extension of our initial internal VoIP network. In this second scenario we
want to allow each VoIP client to reach the PSTN. In order to do so we need a special hardware that
connects the PBX to the PSTN.
In this example, we are using the TDM400P PCI card from Digium with one FXO port. Remember that
the TDM400P card is a versatile card that allows a maximum of four FXS/FXO modules and that one
FXO module allows the PBX to connect to one analogue telephone line.
8.1 Adding support for the TDM400P card
Four basic steps are needed to get the TDM wildcard up and running.
Step 1: Insert the PCI card
The first step is to plug the half-length PCI card in a free slot and connect the big molex (12/5 volt)
connector to the computer power supply. The TDM card gets power by means of a female molex
connector (it is the same 4-pin connector that comes in a standard IDE hard drive). If you do not have a
free male molex connector, you need to purchase a power splitter.
Step 2: Install the hardware drivers
Page 34 TRICALCAR | www.wilac.net/tricalcar – Version: February 2008