Asterisk is often described as a PBX in software – that is, a system for routing and connecting calls in a building or office. Asterisk’s developer prefer to describe it as ‘communication server’ since it’s the engine that powers a whole range of communication application including automated menus, call centres, conference bridges and voicemail servers.

Basically, these kinds of functions have been by proprietary telephony systems which can be prohibitively expensive. Asterisk, however, provides all these functions for a nominal cost: a little time invested in learning the system, some commodity PC hardware and an internet connection is all that’s needed.

You can download a copy of asterisk from http://www.asterisk.org/asterisknow/

There is a quick start guide available on the Asterisk website to walk you through the installation.

You can set up Asterisk using the internet to carry calls. This requires zero up-front costs, so you can set up a system and test it without paying out for exotic hardware. You’ll need to sign up with a SIP provider.

In Malaysia, we can use http://www.alienvoip.com/ which is free to receive call.

SIP

stands for Session Initiation Protocol, it’s used for controlling multimedia communications sessions over the internet. Essentially, it’s a protocol for what’s known as Voice over Internet Protocol (VoiP)