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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!
Some of the call filtering and voice mail things can be done with vgetty, an extension of mgetty. A $10 genero rockwell will do well with it. It's not a pbx but it's something for cheap.
What did you eat today? http://www.atetoday.com/
You might find this interesting. Search the page for 'PBX', it brings up some possibly useful links.
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 build a PBX with Intel (formerly Dialogic) "MSI" boards. The MSI can take an analog interface from the outside and generate ring and dial tone for your station sets. You can use an SC bus capable voice board for voice mail. Ought to be able to find this stuff on e-bay at a reasonable price. As for how-tos, there is a wealth of material on the dialogic/Intel support site Check out the various documentation, especialy the the "Application Notes." There are also forums you can join for free and folks on the forum are very knowledgeable. The bayonne user community is also very helpful. I've been dying to do this kind of project for years but haven't had the time. Enjoy!
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've got faimly membrers in all the major calling areas in my state. My brother and I have pondered setting up a local calling network using Openh323 and cards from http://www.linuxjack.com/.
Well, you could always search google, or for general tech acronym descriptions this site is often helpful. from the techweb site:
(Private Branch eXchange) An inhouse telephone switching system that interconnects telephone extensions to each other as well as to the outside telephone network (PSTN). A PBX enables a single-line telephone set to gain access to one of a group of pooled (shared) trunks by dialing an 8 or 9 prefix. PBXs also include functions such as least cost routing for outside calls, call forwarding, conference calling and call accounting. Modern PBXs use all-digital methods for switching, but may support both analog and digital telephones and telephone lines. See IP PBX and WPBX.
Just a reminder, a home PBX might be cool, but if your phones go through a PBX, you need to make sure you have a regular phone in case the power goes out.
PSTN vs. POTS isn't an American vs. British thing. The Public Switched Telephone Network (PSTN) is the public phone network used ing your country (or the world), it consists of many large switches all kinds of different phone connections, including optical fiber, satellite, undersea cable, frame relay, T1, and even POTS (plain old telephone service), which is a simple twisted pair carrying one analog phone conversation and enough voltage to ring a heavy electromechanical bell.
The PSTN is like the telephone version of the Intranet, and a PBX would be the telephone version of a LAN.
The wife (who is a phone tech by day) says you need a Toshiba DK40 + Stratagy voice mail. I've programmed the DK 424 myself (with the add-on computer interface) and have to say it wasn't too bad. Don't let the sales guy tell you you can program it all through the phone though :)
What if it is just turtles all the way down?
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?"
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.
One thing I'd like to use that for is to leave messages for people who call in by letting them enter a PIN.
The only problem is the software, the projects on sourceforge don't seem to be that far along yet
I'd also check out VoIP for intercoms. There is opensource software for that. You could build your own VoIP intercoms/phones with a single board computer with built-in sound, or a usb soundcard, or the Creative Labs VoIP Blaster (there's oss called Fobbit to use that with Linux)
I picked one up for next to nothing that has four ports (four simultaneous voicemails) It came with a 286 (!) computer and a 100 meg hard drive that had hours and hours of recording time. DOS based of course (though I've heard that the newer ones use OS/2). As to a phone system...I'd look for small companies going out of business and offer to buy theirs cheap. A friend of mine got a Panasonic 10 line/25 phone digital system that way for 50 bucks (and he had to remove the PBX from the wall and unplug the phones).
The Linux Answering Machine HOWTO is not exactly what you're looking for, but surely a good start.
It is easier to get forgiveness than permission.
http://vovida.org
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There you'll find a scalable open source softpbx that's scalable to the 5000 phone range. It's got Cisco research dollars pouring into it, and it's currently free. They have a soft client too! This thing has billing modules, h323 compatibility gateways.. Works with Cisco's VERY cool sip phones
It really is aimed at the carrier type people.. but hell..it's pretty easy to get it all running on a P2-450
Take it easy all
-=-Ze End-=-
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!