Monday, June 30, 2008
What is Asterisk?
Asterisk is an Open Source PBX & Telephony Platform. It’s often labeled as the future of telephony.
PBX stands for private branch exchange. It is a machine that handles many businesses telephones calls for you. Its main functions are to transfer calls to different individual phones; play music when somebody is put on hold; to play automated voice responses when a call is received; to provide an options menu for the caller etc.
Asterisk allows one to build their own phone systems. It adds features, functionality and reduces deployment costs in ways which; at first are a little difficult to understand.
How does this relate to amateur radio?
Very simple, the future of two way radio is digital. As of writing, TV are required to be full digital and shut down their analog transmitters in Feb. 2009. The only spectrum broadcasters are required to vacate are channels 64 thru 69 that will become the new "700 MHZ band" that is being auctioned off by the FCC. The vacated areas of this spectrum will be utilized for: Public Wireless deployment (Cellular/PCS); A wide-band private data network that will be shared between public safety and paying customers; and new spectrum for public safety that will butt right up to the re-located NPSPAC National Public Safety Planning Advisory Committee band being moved to 806-809/851-853 by Sprint/NEXTEL.
Public safety also has guidelines to migrate to APCO-25 digital. The future of two way radio is digital, and we must also advance in this direction. The digital premise is that it generally allows more use in a more efficient/flexible use of band space.
Most present day government communication centers that use analog systems happen to have a VOIP based dispatch console. This analog to VOIP patching is something that we are presently also embracing in ham radio with IRLP, EchoLink, Yeasu WIRES II, and the like.
A different hardware board for each of these proprietary VOIP systems that you want to support is required. You also need a need a multi-port repeater controller, to support each hardware boards analog breakout. This seems redundant to me, and is something that slows the advancement. IRLP seems to be the system of choice because it runs on the Linux operating system. This is because Linux is much more stable that Windows, and is an open source development.
Your seeing the migration in the commercial world as I pointed out; hello digital TV. And the only analog part left of traditional telephone is the “last mile” drop to your home. Time Warner and now AT&T are providing digital phone service to close that up too.
I really feel there "Could be" something big with Asterisk Telephony and perhaps D-Star. The marriage seems natural. I even think it can be integrated with existing VOIP systems like D-Star and EchoLink.
I feel anything is only a "could" type of thing, only because of how the concepts are presented to the amateur audience. This hobby is supposed to be about advancing technology...
As of writing there aren't any directed approaches to tie this to the hobby that I can point you to. There are a number of open ended ideas from a variety of different people. What I'm saying is there is no one entity steering the ship, so to speak. This ideas are still in development. Which makes it precisely the time to jump aboard and get our hands in it and see what we can do with it. So in light of that I suggest a google search for more info... Once you get interested you're likely to bump into myself or other hams on various message boards. And you will likely also have run across a few ideas on how to integrate it to the hobby.
If your interested in giving Asterisk a test drive I found this video overview a good starting point for myself. AsteriskNOW, or PBX in A Flash are both good starting places. They are a Linux install with Asterisk and a Asterisk GUI rolled into a bootable ISO CD install.