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Suggestions for Home PBX/Key System?
foobar104 asks: "I'm fascinated by the idea of putting in a home PBX or key system. I don't really have a good justification for this; it just sounds like a neat thing to have. There are commercially available small PBX systems available for $500 to $2,000, plus another $500 to $2,000 for voicemail, but putting in one of those doesn't sound like as much fun as building one from scratch using an older PC and some off-the-shelf components. I'm wondering if anyone has suggestions for sources of information, tips, HOWTOs or other knowledge on this subject? I'm sure it's been done before; GNUCOMM and GNU Bayonne are out there, but I'm not having much luck finding tutorial-type info about them."
"The system I want to build doesn't need to be complicated. I'd like to have two outside lines and about five inside lines. I'd like the system to have all the standard cool features, like intercomm and station-to-station calls and such, but I'd also like to do some exotic things. For example, I'd like to implement a call whitelist system, where during certain hours of the day, only calls from numbers on a pre-defined "white list" ring through, and all other calls go to voicemail. I'm guessing that something like that will require programming, and I'm not afraid to get my hands dirty. I just don't know where to start.
It sounds like a fun hobby project-- to me anyway. Can anyone point me in the right direction?"
Check out the Asterisk PBX system by Linux Support Services. http://asteriskpbx.org/
It is all linux based and the hardware is very nicely priced. I have this running at home and love it!
Why would you want a PBX system in your house? how many people live in your house?
Two... but that's obviously not the point.
I'm looking for features. Features like programmable voicemail and room-to-room intercomm are easy, and they're available at reasonable cost from companies like Panasonic. But the more complex stuff, like call filtering by caller ID, call forwarding by caller ID, day-night programming, and so on... those are harder. That's why I'm hoping somebody can help me out with building a scriptable, configurable system using off-the-shelf hardware and software as much as possible, and homegrown software where necessary.
I really thought I made this clear in my submission. Maybe I was wrong.
You can always find pbx systems on E-bay relatively cheap. My house has a 15 year old system that I got out of an old office building. has 2 lines running into it, voice mail, and runs fine.
However, I want to kludge up something as well so here is my research for you.
http://www.mtnsys.com/ Software
http://www.openippbx.org/ Nix software
http://www.virtualpbx.com/ More software.
Hope this helps.
Puto
The Revolution Will Not Be Televised
I have one too - 8 extensions, 3 lines (2 connected). Panasonic PBX: takes key sets or analog sets
That is one of the most important variables: can you connect cheap analog sets, or must you use expensive key sets?
Used to be a phone engineer so it's an interesting hobby but also useful: share 2 lines, connect through, redirect fax calls to the fax, etc - recommend you buy a cheap analog PBX - few hunbdred bucks in Europe.
MW
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BDOS ERR ON A:>
You might try VOCP. Good open source call routing system. Even has web integration for retrieving your calls over a network.
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
The one thing that would concern me with making your own PBX out of an old PC and some CTI cards is reliability. What if the system crashes and someone needs to dial 911 or another emergency service?
Keep at least one analog 500 set wired directly to a trunk/outside line.
Calum
Dealing with phone lines is a PITA. Look at the innards of something like a Panasonic PBX ( I've had one in the house for 10+ years), and one of the first things you notice is that a large percentage of the circuitry deals with spike and surge protection for all the lines going in and out of the box.
I've thought about homebrewing a system, but don't have a 30 hour day just yet. The panasonic box is reliable -- it just sits in the closet and works. Oh, when power fails, it automagically switches the CO (incoming) lines to the first n extensions, so you're not totally screwed.
Features with unintended consequences department: One cool feature of the panasonic system is the doorbell boxes. Put one on the front door, and you can answer the door from any phone connected to the system. Unfortunately when I first set up the system, the front door also rang the extension with the answering machine on it. We went away for the weekend -- when we returned, we found that the answering machine had been answering the front door! Oops! A "simple matter of programming" fixed that.
I myself would just see about buying a used system. Try here or here.
SCO (noun.)- A Slimy Corporate Ogre. Often seeks free money.
am I forced to involve the telco in how I setup my PBX
It entirely depends on what you want to do. Many PBX systems are perfectly happy sitting on a single POTS line. One caller ties up the entire system except extension to extension calls. This is what you commonly find at very small stores where you ring in and then punch up an extension. Busy's are common. The system is referred to as a key system. A user has to select one of the unused outside lines to place a call and has to select one of the ringing lines (or line on hold) to answer a call.
A Private Branch Exchange is much more than a fancy termination for a POTS phone line. They run on some trunk lines. This does require some work on the Telco end to make it work. On the Key system, if one line is busy, callers would have to try later or try one of the other lines numbers. The Telco can have it so if the primary number is busy, it will roll over to a secondary number.
On a trunked system, it is entirely diffrent. You can select diffrent numbers of incomming and outgoing trunks. In-comming calls and outgoing calls are placed on the first avaliable trunk. (you may have seen this, Dial 9 to get an outside line, not pick up line 3) Incomming calls as well as outgoing lines are trunked seprately. An example is an order desk using an 800 number. (operators standing by...) Many calls can be received limited by the number of incomming trunk lines and avaliable operators. The call center may have as few as 2 outgoing lines. A telemarketing center may have hundreds of outgoing trunk lines but just a few incomming lines.
Another class of trunk is called DID, for Direct Inward Dial. You most likely have seen this for paging and not known it. A paging company may buy a block of 1,000 phone numbers and have them placed on 20 trunk lines. When you dial the regular phone number to call a pager, it picks up any free trunk line to the paging switch (sometimes as few as 10 trunk DID lines) and the phone company sends the last 3 digits of the dialed number. This way 1,000 phone numbers will fit on 10 or so lines. The calls are short so few callers will experiance a busy.
DID lines are used for many PBX's so you direct dial a department or persons desk without dialing an extension. You can get DID for 1-5 digits to cover 2-100,000 phone numbers. A 1 digit DID does not require reserving all 10 numbers, 2 digit 100 numbers, etc. Getting 20 numbers reserved on a 2 digit DID can be done. My work phone is an example of this. To save on copper wire, all of the trunks can be multiplexed on an ISDN line or dedicated fiber optic line.
Going trunked is overkill for home use. Look for stuff that will work on a POTS line. Some stuff is set up for trunked service and may support DID or ISDN.
The truth shall set you free!