Asterisk allows people to communicate using the internet. It is one of the cheapest ways to talk. The PC clients connect to each other through an Asterisk server which uses a Linux/Unix OS.
Asterisk calls can be passed through different channel protocols. The most popular forms of calls are H323, SIP, IAX or Zap. Depending on the type of channel you use, the user must have the appropriate software to handle the call type.
Example:
If are a registered on an Asterisk PBX(or other PBX) as a SIP user, you are required to use a SIP phone client such as Idefisk 2.0 or SIPPS. Or, if you are registered as an IAX user you must use an IAX phone client such as iaxcomm.
SIP/IAX Client Configuration:
Now, we will describe how you can register SIP and IAX users. This includes the adjustment of all Asterisk and client phone settings.
First, make sure Asterisk is installed. Most of the files to be modified are stored in /etc/asterisk.
To make calls with this kind of telephone system you should have the following:
-Connectivity to a Asterisk PBX for call handling
-Users using PCs with SoftPhones for calling internally and externally
All configuration information for the Asterisk PBX knows is written to the conf files located in /etc/asterisk.
Example:
All information for SIP users is stored in sip.conf and for IAX users in iax.conf. Numbers are read from extensions.conf. Voicemails are stored in voicemail.conf etc.
To place a call through Asterisk, registration to Asterisk is not required. However, you do need a username and password which will allow you to call someone who is registered.
To receive a call, you must be a registered user and have an extension.
