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Industry-Standard VOIP Phone Using All Free Software 138

Ralf Ackermann writes: "Voice over IP on a HardPhone running Linux and just using Open Source software became real. We have sucessfully installed and tested (interoperability with Cisco 7960 as well as Pingtel xPressa in an environment with a partysip SIP registrar and proxy) the linphone SIP phone on a StrongARM based TuxScreen. Here is the link describing the steps for others to use the setup as well: TuxScreen running SIP. All the infos for setting up a comparable installation can be found on the URL, please also feel free to ask or drop opinions. Many thanks to the linphone developers as well as to my student Florian Winterstein (for working on a console linphonec version). The setup (on a StrongARM system) is well suited for PDA (iPAQ) or wearable environments as well."
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Industry-Standard VOIP Phone Using All Free Software

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  • SIP (Score:2, Informative)

    by Fantanicity ( 583135 )
    SIP is an open protocol [], so what is special about this?
    • Re:SIP (Score:3, Informative)

      Most of the SIP phones I've seen (like the Cisco and Pingtel ones mentioned in the article) cost as much as a low-end PC, so maybe open source SIP software can help to bring down the cost of SIP phones in the future.

      And there's also the hack value. :-)
  • With a VOIP WiFi "cell phone" you could conceivable talk to anyone in range (peer-to-peer) at no cost, and to anyone connected to the internet if you are in range of a base station.

    You even already have an MPL'd H.323 protocol library [] to provide communication with NetMeeting and GnomeMeeting [] users. In fact, I've been looking for something like this which could compile on the LinuxARM architecture, in order to turn my iPAQ running Linux into a WiFi cellular phone.
  • What about SNOM? (Score:4, Interesting)

    by DragonWyatt ( 62035 ) on Saturday June 15, 2002 @10:31PM (#3709760) Homepage
    Check this [] out for another linux-based VoIP, standards-compliant (both SIP *and* H323) phone.

    It's been out for quite awhile, over a year. My company is a reseller. They're cheap (~ $199 each) and they rock.
    • Check this out for another linux-based VoIP, standards-compliant (both SIP *and* H323) phone.
      ... They're cheap (~ $199 each) and they rock.

      Cool. Since you seem to have some knowlege about these phones, is there plugin or module of some sort included for encryption? If not, is it easy to tunnel through ssh? It seems to me that a VoIP telephone directory could also serve the public key (or fingerprint at least). It would just be a matter of trust.
      • Re:What about SNOM? (Score:3, Informative)

        by DragonWyatt ( 62035 ) there plugin or module of some sort included for encryption? If not, is it easy to tunnel through ssh? It seems to me that a VoIP telephone directory could also serve the public key (or fingerprint at least).
        Nothing that I know of, but that's an awesome idea. It would probably require a new extension (well, codec).

        The way we've solved that problem to date is with VPNs, which incidentally solve other problems, such as QOS.
        • "Hey, Pinkie! Are you pondering what I'm pondering?"

          "Well, I think so, Brain. But how can we launch a VoIP phone directory with just a couple of servers and a database? I mean (NARF!) even before we add the public key fingerprints and web-of-trust links, we are talking about gigabytes! And we're just a couple of mice!"
  • by Anonymous Coward
    But I'm still coughing up $20/month for basic phone service. That's $240/year folks. And where's that $240 going? Maintenance? I'll enjoy seeing these fat dinosaurs be replaced by VOIP.
    • I'm sure there is some equipment and line maintence necessary, but the marginal cost of another telephone line is basically 0.00... the biggest expense is printing and mailing the bill!

      However, a recent bill had local charges of $36, long-distance charges of $2.88. And state/federal/fcc/usf charges of $11.36!

      a 29% tax rate on a more-or-less necessary service!

    • Yeah but do you think things will be any different? Who will regulate VoIP when it is ready to replace what we currently have?

      Maybe I'm being pessimistic here, but I think that when VoIP is phased in, we may see lower prices but the system will still get the shit taxed out of it. Essentially, the only thing that will change is the technology underlying the means of how we communicate. Then again, that's just my opinion. :)
    • Until you start getting network congestion messages every time you make a call.

      Am I imagining things or is net traffic and latency going to be a real serious problem before these can become used abound?
      • I agree. There was an article here [] on Slashdot that talked about Internet2:

        An international team set a new record for Internet performance by transferring the equivalent of an entire compact disc's contents across more than 7608 miles (12,272 km) of network in 13 seconds. The rate of 401 megabits per second achieved in transferring 625 megabytes of data from Fairbanks, Alaska to Amsterdam in the Netherlands is over 8000 times greater than the fastest dial-up modem."

        Perhaps that's what it will take for these phones to be suitable for everyday use...
      • VoIP works very well in a controlled IP network. However, on the Internet, there is no guarantee of control. Telephony service providers that use VoIP technology often use their own private IP network.

        I saw a presentation a few years ago by one service provider who used their own proprietary VoIP protocols over the Internet with VoIP-to-circuit-switched telephony gateways all over the world. Each gateway was connected to at least 2 ISPs, and the gateways would all ping each other to check for congestion. If routes through one ISP were congested, it would switch to the other ISP. If both were congested, it would start routing calls through a backup, traditional long-distance service. Even though they couldn't use the Internet for every call, they were able to use it enough to save a significant amount of money.
    • How often does your Internet connection go down? How often does your router or Ethernet switch crash? Do you ever get a guarenteed or consistant data and latency rate?

      Now how often do your telephone systems crash? How often does the quality of the call degrade or drop during the call?

      Traditional phone systems are consistant, rock solid stable, and can handle a large user base.
    • I'd love to see good evidence to the contrary, but I've always heard the single largest cost for the telecoms is the billing infrastructure and it sounds quite reasonable. The billing adds all kinds of cost intensive human resources to the infrastructure that is supposed to be entirely automated. It requires receptionists, cashiers, accountants and all of the associated business crap. And how many hours do they spend arguing about bad bills and other make work? While the customer argues on their own time, they companies have to pay their represntatives. And so the customer not only has to argue about bad bills on their own time but is paying the salary of the person they are arguing with. That's where monopolies no longer serve the interests of the people. Simply because telecoms evolved from a labor instensive model doesn't mean they get to stay that way in order to create busy work. This is always the argument against communism is that state run enterprises create all thes useless make-work jobs. It seems the private telecoms of the US are striking example of this same make-work inefficiency. The argument of socialist -vs- free market is misleading and off-topic, the point is that any institution that affects the majority of the people and is clearly failing to function for the benefit of those people it influences over a period of decades should not be supported by the society. That has nothing to do with socialist -vs- free market. It's just common sense.
      • I don't know if it is true or not that billing
        is the single largest cost for a phone company,
        but even if that were true it would still be
        necessary. Otherwise, what is to stop some people
        from hogging huge amounts of capacity by making
        thousands of long-distance calls every month?
    • And then there was metered bandwidth, and the phone companies that had acquired cable saw the net bills, that they were even larger than the phone bills had been, and they grabbed their huge bellies and laughed....
  • Xeyes (Score:3, Funny)

    by exceed ( 518714 ) on Saturday June 15, 2002 @10:35PM (#3709770)
    They just -had- to include the Xeyes in the screenshot.
    • Heh... you know they were probabbly using it the whole time:

      notie how tiny and dark lookin' the screens were? i bet it's a pain in the neck trying to find the cursor on those phones!
    • Re:Xeyes (Score:2, Funny)

      by Joe Kellner ( 585796 )
      Of course, xeyes is the industry standard important killer app for X.
  • The setup (on a StrongARM system) is well suited for PDA (iPAQ) or wearable environments as well."

    But can it turn a cell phone into a PDA?
  • How would I go about replacing my regular land line with VOIP? Do I have to sign up with a VOIP phone service provider? I've looked at all of these pages, but none of them actually tell you how to use them.
    • by Anonymous Coward
      Anything that supports IP which mean ethernet fiber including the internet. It is really not much different than streaming video but you can't take advantage of buffering and must be real time so it is UDP and it does an unrealable packet sequencing on top of UDP which is able to tolerate the loss aof a few packets here and there.
    • If you guys do work on the interface for the phones at your company, then it would be great if you could release your mods ala open source for all of us out here.
      • If they would do a color screen and support skinny, they would make a fortune, especially if the phone was sub $300. Also, the phone would need to support html/xml, ldap and that would be the ultimate. Finally, it a web cam option ca,e with it, you could corner the market in phones.
    • You would need a network of gateways connected to the telephone network at all of the locations you would want to call. Net2Phone [] provides such a service, but I don't think it is SIP compatable. They also supply VoIP software that is compatable with their network.

      Nortel Network's Succession [] products do have SIP as well as H.323 compatability, and they are designed for building large VoIP networks. Also see SIPCenter [] for other venders. Hopefully we will see services built with this stuff soon, and then SIP phones, and SIP software for your PC will be more useful.

  • One step closer... (Score:3, Interesting)

    by Justen ( 517232 ) on Saturday June 15, 2002 @10:53PM (#3709802) Homepage Journal
    The company I work for has been looking at VoIP for several months now. Since we have several offices across the country, it would be very advantageous, technologically, for us to use VoIP for the end-user phones, rather than the hodge-podge of systems we use today.

    Unfortunately, the prohibiting factor has been the cost of the phones themselves. The cost for an actual system is within reason, but some VoIP telephones run into the $700 range.

    At this pricepoint, it seems much more affordable and reasonable. And while the GUI would need work to make it dummy-friendly, we have no shortage of graphics designers and programmers who could make that work.

    One step closer to VoIP from beginning to end makes me happy. And I know it'd make our CFO happy, too. =)

  • I used to run something like that on the dark side of OSes, but now my cell phone plan is so cheap with practically unlimited nationwide long distance and free roaming, I have *zero* need for such a thing. The only time I could see that it might be useful nowadays is if I were making a lot of overseas calls.
    • Very good point. I pay $50 a month to AT&T and I can make 600 peak minutes, unlimited nights and weekends, and free longdistance anytime. This covers any use I have for a phone and if weren't for occasionally needing the fax machine and to make international calls, I'd even cancel my land line service and use the cell exclusively.

      Voice over IP would be great for international calls though. I can't even place an overseas call from the cell.
  • by heretic108 ( 454817 ) on Saturday June 15, 2002 @11:05PM (#3709825)
    Just mix in a few 1000 digit primes.
    Chop fish into 128 pieces, add and blow.
    Simmer and stir, and allow 1-3 secs for CPU to cool.
    Talk when done.
  • by peterdaly ( 123554 ) <petedaly&ix,netcom,com> on Saturday June 15, 2002 @11:12PM (#3709838)
    I do not understand why IP phones
    a) have so low market penetration
    b) cost so much
    -- I know part of the problem with a is b.

    What I think really is needed is a low cost, high quality server system for one of these systems. Based on what little research I have done, it costs almost as much, if not more, for hardware for a small office system as it would to get a real small PBX like phone system.

    I don't think a phone really needs a 9" LCD screen, or whatever was in the screen shot, but the "Java Phone" from the other company has a screen size perfect for the company phone directory. That I think could be the "killer app" for these things.

    Anyway, anyone know of low cost PBX software (if that is even what is is called in the IP phone world)? Open Source, under a BSD like license would be cool, and lower the barrier to market entry for companies wanting to roll a system like this out. Of course, cards to hook up to a POTS connection would also be needed. Voicemail over the web, via shoutcast or something would rock. I havn't listened to my voicemail at work in 3 months. With a better interface, I may stop refusing to use it.

    • Asterisk []

      VOCAL []
    • I do not understand why IP phones
      a) have so low market penetration

      All of those Netware users are still waiting for VoIPX.

    • Unfortunately, the reason is all too clear.

      a) VoIP phones have such a low market penetration because...
      b) VoIP phones cost so much because...
      a) VoIP phones have such a low market penetration because...
      b) VoIP phones cost so much because...
      a) VoIP phones have such a low market penetration because...
      b) VoIP phones cost so much because...
      a) VoIP phones have such a low market penetration because...
      b) VoIP phones cost so much because...

      ...and so on and so forth...
    • but the "Java Phone" from the other company

      Could you provide a URL, or at least a product name for that?
    • It's a myth that VoIP phones don't have market penetration. The first thing to remember is that a PBX's life is like 5-7 years. 2nd, most companies spent a lot of $$ for the Y2K upgrade, so a company isn't just going to rip out a system for a new VoIP system just for the sheer coolness of it.

      In terms of new phone systems being put in, VoIP is winning hands down. It's usually cheaper, hardware wise to move to a VoIP system, maintenence is cheaper, PSTN charges are lower.

      Nortel and Avaya are getting KILLED in the enterprise market right now. Both have PBX sales down 25% and their stocks are almost rock bottom.

      VoIP is winning.
  • The next step (Score:4, Interesting)

    by FueledByRamen ( 581784 ) <> on Saturday June 15, 2002 @11:31PM (#3709884)
    This is fine for intraoffice communication, but what about the real world? I think that a solution for connection VoIP -> POTS could be easy, with a little knowledge of Linux drivers.

    Get an older box (P2 400 or so), with plenty of PCI slots, and preferrably an onboard NIC also. Get some Winmodems equal to the # of pci slots.

    WinModems, even in all of their Microsoft-sponsored godless evil towards open source platforms, are basically A/D and D/A converters hooked to a phone jack. It should be relatively simple to talk (no pun intended) to them in software and use one as an interface to POTS. It has all of the neccesary hardware, and writing a sound driver for it shouldn't be too difficult. A brand of WinModem with fairly standard hardware could be decided on by the implementer, and drivers written for that. (Winmodems? Standard? ...)

    Client software with available source code could be modified to use those, as well as control the phone-line functions. Just run an instance per WinModem.

    Honestly, I think that this could work, and it would be a great hack to accomplish. Anyone fancy a go at it?
    • by mosch ( 204 )
      yes, i will gladly create software for undocumented proprietary devices which weren't neccessarily designed to be able to reproduce speech, for free!

      but first, watch me play with myself live, at [].

    • Re:The next step (Score:3, Interesting)

      by elandal ( 9242 )
      I think that'd be pretty inefficient. Rather, get a card that talks to PRI. Don't know of any such cards, but they're very likely to exist. And if they don't exist, find a small engineering shop nearby and ask what would it take to put one together.

      Think about it.. A box with six PCI slots and mobo-NIC using six WinModems could handle six phone lines - old analog lines at that. While a single PRI-card could handle 30 lines, and considering that each ISDN line is just 64000bps (8000 samples at 8bits per second - if I remember correctly), it doesn't really all that much computing power, so a single PC should easily handle it.

      Of course a small shop doesn't need 30 phone lines, and could do with the WinModem-based setup, and those that need can get the VoIP from the telco, not needing their own VoIP-POTS conversion.
  • I could not find any mention of the TuxPhone hardware (phone) itself on the site other than the photo, and discussions about the embeded lcd/strongarm thing. No mention of how it links with the phone in the picture, etc.

    Are there any "low cost" IP telephones in the market today? $600 (what looks like the going rate) seems like too much to me.

    • The TuxScreen phone itself was selling for $99 not too long ago. I have one in my closet (which I will now have to drag out so I can play with this project).

      IMHO that's what makes this implementation so revolutionary. Other posters were asking why this is newsworthy? Well, a $100 phone that runs open-source VoIP is pretty newsworthy to me. I've done both VoIP and voice-over-frame-relay installations, and you're talking about thousands of dollars for even a small implementation (using IP phones or regular digital PBX phones, special cards in the PBX and the router, special software, and so on).

      Compare this to $100 phones and a gateway running on a cheap Linux box.
    • Oh yeah, here's the link to purchase one []. Tim says they still have more than 200 phones left at $99 each (but read all the way down the page; you may want to have him unlock the flash chip and/or reflash with a Linux-compatible bootloader for you, which costs a few bucks more)
  • by jmv ( 93421 ) on Sunday June 16, 2002 @12:22AM (#3709960) Homepage
    (shameless plug) Take a look at Speex, an open-source, patent-free speech codec (Speex is to speech what Vorbis is to music). Speex should soon be available in Linphone too!
    • Okay, maybe I'm an idiot, but the "female" samples on that site are the exact same size. They also differ in only one place in the file.

      • Okay, maybe I'm an idiot, but the "female" samples on that site are the exact same size.

        Of course they are, what would you do with a file called "female_speex.vxz" ?
        The file is decompressed again into a .wav file so people can compare the quality of *before* and *after* compression.
        Regarding the filesize, the site says: 15.1 kbps, and the file is about 6 seconds, which would make the compressed file about 11.3 KB

        They also differ in only one place in the file.

        Realy ?


        00000 52 49 46 46 24 77 1 0 57 41 56 45 66 6d 74 20
        00010 10 0 0 0 1 0 1 0 40 1f 0 0 80 3e 0 0
        00020 2 0 10 0 64 61 74 61 0 77 1 0 ed ff ee ff
        00030 eb ff eb ff f1 ff f0 ff f5 ff f2 ff f7 ff fe ff
        00040 fb ff f7 ff f9 ff f2 ff f9 ff f4 ff f4 ff f7 ff
        00050 f8 ff fc ff fb ff f9 ff f5 ff f7 ff f7 ff f4 ff
        00060 f7 ff f4 ff f2 ff ee ff e7 ff e8 ff e8 ff e7 ff
        00070 e7 ff e6 ff e7 ff e4 ff e8 ff ea ff e8 ff f0 ff
        00080 eb ff ea ff e4 ff e6 ff e7 ff e7 ff ea ff e8 ff
        00090 ea ff ea ff e7 ff eb ff ed ff f0 ff f8 ff f5 ff

        00000 52 49 46 46 24 77 1 0 57 41 56 45 66 6d 74 20
        00010 10 0 0 0 1 0 1 0 40 1f 0 0 80 3e 0 0
        00020 2 0 10 0 64 61 74 61 0 77 1 0 0 0 0 0
        00030 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
        00160 0 0 0 0 0 0 0 0 0 0 0 0 f7 ff f4 ff
        00170 f3 ff f2 ff f5 ff f1 ff f7 ff f1 ff f4 ff fb ff
        00180 f9 ff f8 ff f8 ff f5 ff f4 ff f4 ff f3 ff f7 ff
        00190 fa ff fa ff f8 ff f7 ff f5 ff f6 ff f6 ff f7 ff

  • Although it seems liek VOIP has little or no market share in north america, it is a completely different story in the developing world.

    I was travelling through asia and later in south america. Callign home using a conventional calling card was ridiculously expensive.

    But, a lot of little businesses were around offering international calls for very cheap. From Laos to canada for 15 cents a minute. Sure there was a little delay, but it was well worth it. All of these were using some sort of VOIP box./

    In places without much telecommunications infrastructure, especially when most of the peopel own cell phones and not land phones, VOIP allows the convergence of all sorts of telecommunications traffic onto one simple infrastructure.

    And by using open source software, free to all, the third world can much more easily afford it.

  • VOIP for PCs? (Score:2, Interesting)

    by fopa ( 585802 )
    Any info on VOIP for a regular PC? I need international long-distance access. I saw this Ask Slashdot article [] that recommended Speakfreely [], but I haven't had time to try it.

    Any advice?
  • Kind of off-topic, but does anybody know of a voice chat package that works on both Windows and Linux? Preferably usable over slow (4 KB/s) connections. I know about Speak Freely, but it gives my friends (who use Windows) only noise.
  • FYI (Score:4, Interesting)

    by Cyberdeck ( 15901 ) on Sunday June 16, 2002 @02:31AM (#3710168)
    Just a couple of points I'd like to comment on.
    Open Source VoIP and telephony is tracked at

    VoIP hardware (PCI cards) is IIRC $79, gateways are $179, drivers have been in the kernel since (again IIRC) 2.2.16.

    VoIP in the U.S. is almost pointless because the PSTN is too good. No one wants near perfect when perfect is cheap and easy. In the third world, if you can get a phone circuit it averages $1.27 per minute, whereas VoIP through a hop-off provider like Net2Phone ( runs average about $0.23 per minute or less. Straight IP to IP (like across a VPN from company branch to branch) is just the cost of the ISP (usually flat rate). So VoIP cafes are a popular way for the non-super-rich and powerful to make calls to their relatives in the first world.

    Personally, the VoIP calls I have made have an almost imperceptible latency problem and sounded *far* better than any GSM call I have ever heard. Then again, these calls were during business hours so net congestion was not an issue for me.

    The Ogg Vorbis has a low bit rate mode that is useful for VoIP telephony, and is grossly better than GSM to my ear.

    Finally, VoIP is used by the big players here in the US. Qwest and Sprint use VoIP in preference to ATM due to cost of the equipment (Bits per second/price of hardware. IP is more efficient than ATM due to less overhead). Any cross-country call is VoIP nowadays.

    Just my two bits.


    • by dmiller ( 581 )
      VoIP in the U.S. is almost pointless because the PSTN is too good

      What about interstate or international calls? If your ISP doesn't volume charge, then surely it would be attractive.
    • Re:FYI (Score:2, Interesting)

      by Bookwyrm ( 3535 )
      Strictly speaking from a bandwidth usage point of view, IP is not more efficient than ATM for voice, unless you allow for higher latency per chunk of voice data.

      That is, ATM has a fixed, roughly 10% header overhead per cell compared to data payload. IP can have lower relative overhead by having larger packets verses the IP header size -- *however* the time it takes to gather the data to fill one large IP packet increases the delay.

      For instance, if you are using an 8:1 compression codec, then that 64K bits-per-second voice becomes 8Kbps, or 1KBps. You can fit that entire one 1K bytes into a single IP packet, yes -- but you have to wait one entire second (the time it takes to gather that second of voice) before you can send the packet. With 8:1 compression, each byte of data is roughly 1 millisecond of voice -- each byte you pause to gather adds one millisecond delay before you send the data.

      ATM becomes more efficient for voice as the payload size decreases per IP packet below around 300 bytes (i.e. 300 milliseconds delay in voice transmission between the first byte encoded and the last byte encoded before the packet is sent.) IPv6 will have an even poorer efficiency, of course, due to the larger header.

      This is not comparing the cost of ATM network hardware to IP networks, just commenting that from a strict data point of view (i.e. bits per second of payload), ATM is going to be have better efficiency/quality for voice data. Now, for mixed voice and data networks, that may not be the primary concern.
    • Re:FYI (Score:3, Informative)

      by Sycraft-fu ( 314770 )
      Cox (tha cable company) seems to disagree with you. They receantly told us (as in the people I work with) that they'd installed their las PBX, they were going all VoIP now.

      End users will start wanting VoIP too. For one thing other providers, like cable companies, will be able to offer it where they can't offer PSTN service. As with all competition, this should give lower prices and more features.

      Speaking of features, VoIP has plenty of cool ones. I really like the Cisco phones (other probably have it too, they are jsut what we tried) ability to be logged in to. You log into a phone, it acquires your number and all your preferences.

      However where it will probably be the biggest winner is for bussinesses. Whenever we setup a remote site they have to have enough T1s to cover all the phone lines they need plus T1s for data. With VoIP, we could elimante a bunch of those since with PSTN you have to have a B channel for every phoneline and with VoIP you need only enough bandwidth to cover your peak line usage. These palces never hit 100% usage and probably rarely hit even 30%, hence all that overhead can be eliminated. It also would simply things on our cable plan. We'd only need fibre to a building, then all vocie and data would run over that.

      Personally I think that VoIP is sort of a slow inevitability. IT won't happen overnight, but it makes so much ecenomic sense that we'll migrate totally to it eventually.
  • This is what Vonage gives their subs....I've had it for about 3 months and the quality is indistinguishable from a normal phone... 6.htm
  • VoIP using only Open Source isn't new, nor is interoperability with Cisco equipment, nor is SIP, or even embedded VoIP using Linux.

    The OpenH323 Project ( has had a H.323 protocol stack availble since 1999. This stack works with Cisco gear and most other commercial H.323 products, and works on Linux, *BSD, Windows and other systems.

    A full GUI Linux client using this stack can be found at

    There is also a SIP stack available as part of the OPAL Project available from the same site. Others are also available (see for one example.

    Lots of companies (including my own) have been doing "real" VoIP using Open Source for years.

    (Disclaimer: I'm one of the authors of OpenH323)
  • ...head over to []. Be quick there are only a couple of hundred left. They are $99 each. Have Fun.
  • All of the phones put out by Cisco and Call Manager (the server that runs everything) don't use SIP, they use the open protocol SCCP or Skinny. If you hook up a SIP phone and try to register with Call Manager, it won't even work, as Call Manager dosen't support SIP. Nor is Cisco too hot to trot on SIP, as you can do less with SIP than with SCCP or even H.323. I've spoken to Cisco about SIP (including CCIE's) and SIP isn't anything special, especially in the enterprise market.
  • Ok so someone figures out how to put phone call data over ip. I'm still looking for someone that has a clue and isn't going to make the excessivly difficult. I currently have two 3com NBX100 (with only a small part GNU code but you can't get source even though they link it all together). These things are 486 boxes (that will boot linux!) that run a complete crap Os/custom app. I've got a cyclades pr4000 but they can't seem to figure out how to dump an analog call into a socket. I can do it fine on a cisco 5200 or a 2600 but not the only device I've got hooked up to a E1 (read T1 for the north american folks). They cyclades people came up with some lame ass excuse that "we figured people wanted "standards" which we couldn't do so we fucked it off. How lame. Oh well, its the last cyclades box I buy unless they seriously get ther act together...

    I can take most of the devices that I've got that hook to decent phone lines and if I get a 64kbit data stream in (aka a phone call), I can dump it to a port. That port can dump audio out in ISDN format (mulaw or alaw depending on its place in the world) and the callie can get a nice message of "press 1 to do splat and press two for garfarbinsplat". Its trival to do an fft that can figure out which touchtone they are pressing and then I can cope with it in one of seval ways. All of this just by redirecting any call taffic to a tcp port on a linux box. Funny thing is I have yet to take advntage of any call set up or three way calling features in this code. It jusst answers the phone, plays back .wav files and figures out which buttons the press. Funny thing is I forgot all about h323 or h3 or any other protcolo but it does work. Maybe I sould got buy a few books on voip to find out how to do this right.
  • My employer is in the process of rolling out a Cisco Callmanager based VoIP system. Cisco 7960 phones are around $250, which probably isn't that outrageous compared to other phones that can handle up to 5 lines.

    The system over all is pretty spendy to install. Servers for call manager, server for Voice Mail system, all new phones, retrofiting with Cat5e. I can't see a big reason for this if I just need to switch 3 phone lines between 5 people. But for a couple of hunded people in a few locations, it's a different story. Phone company here charges $100/hr for a tech to work on our system. That adds up quickly, and much of the work seems trivial. Move this line from this office to another. Change this or that extension. Blah blah $100 blah. We're basically doing this to squeeze the local telco out of our service costs. Now it's all soft, we control extensions, we control dialing rules, we control call blocking and such. All of this is fine because our IT staff isn't overworked, so adding this layer probably won't add any bodies.

    Bottom line is if you are installing network infrastructure and are spending money for managed switches and other hardware, and have more than a handfull of employees, consider making sure your switches and routers are VoIP capable, i.e. QOS, VLAN, etc., and consider replacing your PBX with a VoIP server solution when it comes time to expand or replace. The primary beauty of VoIP for us is 1. Scalability, 2. Independence from local telco 3. More feature rich phones.

    That said, IMO the VoIP revolution is of the LAN, not WAN type.

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