Page 48 - Asterisk™: The Future of Telephony

3.3V 32-bit

5V 32-bit

3.3V 64-bit

5V 64-bit

Figure 2-1. Visual identification of PCI slots
failure due to the extra mechanical connections involved. It can also be useful to
have separate network cards serving sets and users (the internal network) and VoIP
providers and external sites (the external network). NICs are cheap; we suggest
always having at least two.
• The stability and quality of your Asterisk system will be dependent on the com-
ponents you select for its architecture. Asterisk is a beast, and it expects to be fed
the best. As with just about anything, high cost is not always synonymous with
quality, but you will want to become a connoisseur of computer components.

Having said all that, we need to get back to the original point: Asterisk can and will
happily install on pretty much any system that will run Linux. The lab systems used to
write this book, for example, included everything from a Linksys WRT to a dual-Xeon
#
locomotive. We have not experienced any performance or stability problems running
less than five concurrent telephone connections. For the purposes of learning, do not
be afraid to install Asterisk on whatever system you can scrounge up. When you are
ready to put your system into production, however, you will need to understand the
ramifications of the choices you make with respect to your hardware.

Power Supply Requirements
One often-overlooked component in a PC is the power supply (and the supply of pow-
*
er). For a telecommunications system, these components can play a significant role in
the quality of the user experience.

# OK, it wasn’t actually a locomotive, but it sure sounded like one. Does anyone know where to get quiet CPU
fans for Xeon processors? It’s getting too loud in the lab here.
* Or any system that is expected to process audio.

20 | Chapter 2: Preparing a System for Asterisk