[Asterisk] Part 1: Basics and Choosing the right OS

Finally the time has come for our first VoIP or Voice over IP Project. The final goal of this project shall be to integrate an Software Asterisk VoIP System into an already existing PBX / ISDN Enviroment, allowing Users on Analog and ISDN Phones to recieve and send VoIP Calls by using the Asterisk Gateway - and vice versa. An good starting point is the most famous open source Voice PBX, called Asterisk. Asterisk is aviable in many flavors and colors: As commandline on little OpenWRT enabled Routers to an Highpowered Cluster Solution running ten thousands of phones at the same time - beeing managable via an nice looking Webinterface and Batch Files.

As an starting point, myself and Co Worker Sebastian picked out the three most popular releases and integrations of the Asterisk server:

- AsteriskNoW! ( http://www.asterisk.org/asterisknow/ )
AsteriskNow is an development of dignium which does also develop Asterisk.
Uses CentOS.

- trixbox ( http://www.trixbox.org/ )
Trixbox is an PBX which has been build for business use and therefor has many options and special settings.
Uses CentOS.

- Askozia ( http://www.askozia.com/ )
Askozia is using the same system the m0n0wall and FreeNAS Appliances are build upon and is therefor very small and very lightweight.
Uses FreeBSD / m0n0wall / FreeNAS System.

AS for the test systems, we did decide to put all three Systems on real world servers, the first two ones because of their quite heavy weight resource needs onto 2 identical Tyan Tomcat Servers, powered by Pentium 4, 3 GhZ, 1 GB of Ram and an Sata Raid Controller, Mirroring the 160 GB Drive (Raid 1) to a second HDD. We got two 1 Gbit NICs and other stuff.

The test node for the Askozia is an Pentium 2 MMX, 500 MhZ, 64 MB Ram, 8 GB Hdd. 1 100 Mbit NIC and an AMV Fritz Card.

After extensiv tests of the systems we came to choose two favorites:
- Askozia
Because of its very lightweight, very simple configuration and low impact even on the tiny system
Downside: Not many options, shell access only with additional packages, limited expert options

- trixbox
For beeing very powerful and posessing many options.
Downside: Hardware hungry, VERY much options

Having these said we did shut down the two big servers and concentrated on the low end HP Desktop running Askozia. For beeing able to connect to an ISDN PBX we needed support for the AMV Fritz Card. Luckily we found this support included in the stable 1.0.3 release. The current 2.0.0 beta does NOT run with AVM and does not even recognize the Card. I wrote an report on the Forum and the admin did quickly reply to this, I'm waiting for an fix of the problem and therefor continued the work with the 1.0.3. Actually including Voicemail, two Sipphones, Conference Room and such is so easy that anyone can do it within less than 5 Minutes. But first things first - in the Installation How To.