Asterisk Requirment

hi

we are looking for an IP-PBX for testing and launch it as new product for the company… i came accross Asterisk and i need to know what is required for basic setup for an Asterisk system.

like hardware requirments, what OS should be installed, and the capacity of the system…

Linux is a good choice. Any box from the last 5 years is probably sufficient for testing.