Weird Asterisk


I am a newbie in the field of Asterisk, AsterikNow,trixbox, …
I am very excited by the features, that Asterisk family can provide, but it seems also to be a very hard staff.
I need to build a test lab for VoIP (maybe AsteriskNow or trixbox) to show that designing VoIP solutions using asterisk is possible/simple/reliable and can save money, but my manager currently trusts only huge vendors like cisco , hp procurve.

I think such a system can be implemented using a server + interfacing card + Linux + … + IP phones.
But i still have many unclear questions about designing such a LAB.

My Qs:

When do i need VoIP provider ?
how shall the server be connected with users ?? how is the internal connection implemented ???
do i need more than 1 NIC card between server and users ???
FXO/FXS modules are used to connect analog phones and faxes, but how r IP phones connected to the server ?
do i need switches to provide LAN connection between VOIP server and the different users ???

i need really a simple user guide AND/OR design manual to show these steps and how to plan moe complexer designs.

I really believe, that Asterisk is good enough, but it seems, it will take years + many courses to learn the books about the potocols, config. files, dial plans and other staff. So, why not continuing with cisco or procuve … ?

I hope i get answers, that help me to use Asterisk as my first choice or at least for building simple VOIP LAB.


You need a VoIP provider if you wish to place phone calls over the PSTN (phone network) using your internet connection. This is a popular (and cheap) alternative to paying for physical phone lines (like the kind you may see in a house), or expensive business lines (PRIs, etc.) which can cost a large monthly cost, and also require you to purchase additional hardware for your Asterisk server.

Users can connect either via SIP (if your users have software phones on their PCs, or if they have VoIP phones), or users can connect by using normal analog phones that are connected to a FXS gateway. A FXS gateway is an additional piece of hardware you’d have to purchase to plug old analog handsets into, and it will convert them to VoIP.

The traditional way to connect users to Asterisk is via VoIP phones (which can be bought all over the place).

Nope. You can have them all on the same network.

IP phones are connected by ethernet cables (just like computers). They use the internet to connect to your Asterisk server (or the local area network if they’re on the same network).

You could use switches, a router, or a direct connection via a newer-model NIC card. A simple small-business setup would involve an internet connection going to a router with a switch attached. Then you would plug the Asterisk server, and all VoIP phones into the switch so that they would be on the same LAN.

Asterisk doesn’t have good documentation. Your best bet is to use google to find the pieces of information you need. You can also read the free book online: which explains a great deal about Asterisk for beginners.

You can also get a lot of good information from these forums, and the associated IRC channel (

Asterisk, like all open source software, has a learning curve. There is no reason why you should use Asterisk over any other proprietary system (Cisco, avaya, etc.) other than cost. If you can pay for a fancy Cisco server then do it. It will make your life as a techie far easier as Cisco will provide you with all the configurations and you will never have to think about it.

Asterisk is a good tool for everyone else who either:

  1. Enjoys working with open source stuff.
  2. Likes playing around with technology and doing things themselves.
  3. Can’t afford expensive proprietary systems.