Category Archives: IP Telephony

Hello 2012!! The most >Geek< fun I've had in a while

ok ok, so this is really not at all keeping up to trying to post regularly. Got too busy, had a baby, etc.. excuses.

Now, I have a great reason to post!! I just finished a little pet project, tiny one.. but I’m quite excited about it as it’s something I’ve tried to do over 10 years ago, but the products were bad. Now, with newer hardware and software it’s a reality!

I had just succeeded to build my home SIP infrastructure. With a SIP client on my iPhone, I can connect to my personal PBX server, and make calls to regular phones via a SIP to PSTN router.

´╗┐You are lost? I just built my own VOIP system, which I can make data calls over the air, from my iPhone, connect to my home based VOIP system, and call to a land line. What’s so big deal about that? Here in Singapore, the digital land lines are completely toll free! All outgoing LOCAL calls are free. With 3G and 10GB of quota a month, I can make a lot of phone calls this way!

I will share how I did it… and boy, it’s not easy. This setup is not for the faint hearted to even attempt to consider. Leave it to the real IT geeks *cough*

Here’s a glimpse on what you’ll need.

  1. Home broadband connection which has preferably unlimited usage (as we get here in Singapore)
    +the broadband connection must always be up (otherwise you cannot connect from outside of your home)
  2. Home wifi  network, if you want to make calls via your SIP client in the smartphone
  3. A Linksys SPA 3102 (retailing for about S$100 in Singapore) – this is a VOIP Router
  4. Asterisk – a free PBX Server – run this on an old PC, or a small atom machine, or a virtual machine
    (I run mine as a VMware Virtual Machine)
  5. A SIP client for your PC and/or smartphone
    PC – A good and free SIP client called X-Lite (http://www.counterpath.com/x-lite.html)
    iOS – many choices available, free and paid I use the free client from 3CX (http://www.3cx.com/VOIP/voip-phone.html)

Generally, each item is easy to get up and running, but to get them working together was not easy, especially when you don’t understand half the terms involved. This is one of the craziest situations where I was looking at pages of configuration items and they are mostly abbreviated.

In addition, there are few up to date guides on the net which tells you what to do. I found lots of guides for Asterisk, some very good, but are for older versions. I’m using version 1.8, and there are lots that are now redundant. After all I’ve done to get things to work, I must say it’s actually not a lot of settings we need to make.

Credits will be given when due. I will link to the sites which I found the most useful information.