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Security Software Linux Technology

Asterisk and Linux to Build Secure VoIP Connection 140

Posted by samzenpus from the talk-all-day dept.
Beave writes "Using Linux and the Asterisk PBX, it is possible to build a secure, cost effective VoIP (and traditional PSTN) PBX solutions. This article shows you how to take advantage of various hardware, software and tricks to accomplish this goal within a limited budget."
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Asterisk and Linux to Build Secure VoIP Connection More

Asterisk and Linux to Build Secure VoIP Connection

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  • What will the Romans do? (Score:5, Funny)

    by Anonymous Coward on Wednesday November 03, 2004 @09:54PM (#10718938)
    Oh wait, that was Asterix and Obelix.

    s/Romans/phone comanies/

  • Shows you how? (Score:5, Insightful)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Wednesday November 03, 2004 @09:54PM (#10718948) Journal
    More like tells you in the most general of terms what they implemented.

    Obviously what is going to be the real killer app is VoIP in a wireless setup. Instead of having a wall jack for your desk phone, it just hooks into the wireless mesh seamlessly.

    I'm sure this has already been done. I'd love to see an article about it.

    • Re:Shows you how? (Score:5, Informative)

      by Tony Hoyle ( 11698 ) <tmh@nodomain.org> on Wednesday November 03, 2004 @09:59PM (#10718973) Homepage
      It's possible, but the available wireless VOIP handsets are 11b only and don't support WPA (both are showstoppers for me).

      In the future I'm sure they'll become available.

      I use my asterisk server to record incoming/outgoing numbers (the local telco wants paying for this service, although I have to pay them anyway for the callerid so I'm not sure I'm saving much), and to route calls over the cheapest provider (always analogue, as VOIP providers in this country are still 2-3 times more expensive than analogue ones) - which has saved me a fortune.

      • Re:Shows you how? (Score:5, Interesting)

        by itwerx ( 165526 ) on Wednesday November 03, 2004 @10:37PM (#10719230) Homepage
        although I have to pay them anyway for the callerid

        You'll still get it even if you don't pay for it because it's a PITA to truly turn it off in the switch and the telcos never bother. :)
        Call 'em up, ask 'em what the caller-id charge is for, when they explain tell 'em you don't need it and please take it off and voila' - you'll still have it without having to pay...

        • Re:Shows you how? (Score:1, Interesting)

          by Anonymous Coward
          How hard would it really be? With the system as much computer controlled as it is, if they have your account number (maybe pulled it up automaticly when you called?) wouldn't it just be a simple "ok, your caller ID service has been discontinued" and have the system turn it off?

        • Re:Shows you how? (Score:2, Informative)

          by Cramer ( 69040 )
          This is incorrect. As one who has dealt with Lucent 5ESS switches, it's as "easy" to turn off as it is to turn on in the first place. It's one of the many line provisioning options.

          Now, I say "easy" as the term is certainly relative when working with telco switches. I won't bore people with stories; suffice to say the CLI is very cryptic and the menu interface (from which all real work is done) is a bit complicated to the uninitiated.
          • Well, RC (Recent Change) is cryptic, there is no doubt. And an experienced worker can easily change it. The complexity comes in due to bundling with other features (such as 3-way calling and call-waiting) that would have to be un-bundled as a software item on the switch for that specific subscriber. At that time, it does get messier, and I can see some telcos just making the decision to only change the billing side, and to leave the software setup on the switch as is.
            • At that time, it does get messier

              Yep, and customers get pissy when somebody screws up. :) I'm sure in a few years when it's common knowledge that it gets left on and nobody's paying for it anymore then they'll start actually turning it off.
      • It's possible, but the available wireless VOIP handsets are 11b only and don't support WPA (both are showstoppers for me).

        Net2Phone XJ100 802.11g Phone [net2phone.com]

        802.11g but doesn't say anything about WPA. Might be proprietary and only work with their VoiceLine service though. I don't know.
      • > It's possible, but the available wireless VOIP handsets are 11b only and don't support WPA (both are showstoppers for me).
        http://www.zyxel.com/product/P2000W.html [zyxel.com]

        It allows users to make or receive phone calls as long as they are in the coverage of IEEE 802.11b or 11g wireless Access Points. ...
        - 64/128 bit WEP encryption

    • Re:Shows you how? (Score:3, Informative)

      by Student_Tech ( 66719 )
      Well you could get a PDA with a VOIP app running on it. For example, the Zaurus can have either KPhone/Pi [pi-sync.net] or tkcPhone [thekompany.com](demo version on their website). Both of those apps are SIP compatible.

      So you get a PDA and a WiFi conectivity and there you go.

      Probably not the best or most ideal solution, but it is something that does exist.
      • If anyone knows of a VoIP app for Symbian UIQ I'd be very interested - I've been looking around for one to run on my Sony Ericsson P900 phone for ages and so far have found nothing. :(

    • Security wasn't part of Asterisk - it was OpenVPN (Score:5, Informative)

      by billstewart ( 78916 ) on Wednesday November 03, 2004 @11:11PM (#10719460) Journal
      The article said that they did't get their security from Asterisk itself - they added it on by using OpenVPN [sourceforge.net] to build encrypted UDP tunnels and push the Asterisk IAX protocol through them. (No apparent detail on how to configure it.) Some of the Asterisk mailing lists talk about adding encryption to the transport protocols, but as near as I can tell from a few Google hits, that's really all a Wishlist for Somebody Else to implement rather than part of the core protocols.

      That's really too bad - encrypting VOIP causes extemely annoying overhead problems, because the voice data packets are really small (they're not very big before compressing them, and then they're even smaller), so the minimum overhead for just doing the RTP+UDP+IP headers is several times the size of the voice traffic they carry, and IPSEC adds another two layers of headers, or SSL adds about three, and pretty soon that cute little elegant 8kbps compressed voice stream is looking like 40-80kbps and won't fit on your modem. SIP can use the SRTP protocol as a modification of RTP, so to the extent that anybody implements it, it's basically doing then encryption along with a layer you needed anyway, so it doesn't add much overhead. IAX doesn't appear to have this (which is especially frustrating because the IAX2 trunking protocol makes multiple simultaneous connections much more efficient, though I suppose if you've already done that, the extra overhead of IPSEC or OpenVPN may not bother you as much.)

      • Re:Security wasn't part of Asterisk - it was OpenV (Score:4, Informative)

        by cduffy ( 652 ) <charles+slashdot@dyfis.net> on Thursday November 04, 2004 @12:22AM (#10719986)
        ...so the minimum overhead for just doing the RTP+UDP+IP headers is several times the size of the voice traffic they carry, and IPSEC adds another two layers of headers, or SSL adds about three, and pretty soon that cute little elegant 8kbps compressed voice stream is looking like 40-80kbps and won't fit on your modem.

        OpenVPN isn't IPsec, and while it uses the OpenSSL library for all the crypto "heavy lifting", it has its own over-the-wire protocol and is much more efficient than the traditional SSL way of doing things.

        I use OpenVPN at work, and while I haven't done specific measurements, we've generally found it to be very efficient (not to mention easy-to-use and hassle-free compared to its IPsec-based competitors). Because in UDP mode it doesn't try to guarantee reliability, it also doesn't break protocols (like those used for VoIP data) that expect late packets to just be dropped.

        So, in short, I'm not at all convinced that the use of OpenVPN is at all unfortunate or problematic here.
        • If you're running a UDP protocol, you've still got UDP headers and IP headers and optionally Ethernet headers, wrapped around whatever you're carrying, which already had a UDP header and an IP header, all to carry a payload that's only 10 bytes long, or 20-30 with some codecs. Yes, doing UDP instead of TCP takes care of some problems, but it's still a huge overhead for a protocol that absolutely needs to ship a large number of very small packets every second. By contrast, if you're using it to carry bulk
          • If you're running a UDP protocol, you've still got UDP headers and IP headers and optionally Ethernet headers, wrapped around whatever you're carrying

            Not Ethernet headers if they're running OpenVPN in tun mode, which is the intelligent configuration here (tap mode, the bridging configuration where Ethernet headers are used, is mostly used just by folks who want to do Windows networking over the tunnel without a WINS server). OpenVPN also uses LZO compression, which should help with any non-payload data. (
          • As I understand it, this is being applied to protect conversations between two branch offices -- a case where there are likely to be a number of separate streams running simultaniously over the same line.

            IAX2's trunking support should help, then, by reducing the VPN-related overhead in much the same way as it reduces IP overhead.

      • Re:Security wasn't part of Asterisk - it was OpenV (Score:1, Informative)

        by Anonymous Coward
        the minimum overhead for just doing the RTP+UDP+IP headers is several times the size of the voice traffic they carry

        Not necesarily.

        The IP header is 20bytes, UDP is not used ontop of RTP as you suggest, RTP is a slight adaption of UDP which has a header size of around 20bytes again iirc (plain udp is 8 bytes) although that can be compressed. IIRC on average a VoIP packet is around 28bytes although that'd depend on the codec in use. That wouldn't push an 8kb/s stream up to 80kb/s, maybe 25 or 30 if you inc
    • this solution

      1) IPSec is probably better than OpenVPN for something like this. It will be lighter-weight because you don't have UDP headers. There are also very mature open source implimentations, and they will integrate with many third parties.

      2) Any IP addresses on the WAN interfaces could be used for IPSec tunnels.

      Otherwise it is a great tutorial.
    • I did it in my office. I bought a Linksys WET11 (http://www.linksys.com/products/product.asp?grid= 33&scid=36&prid=602) and hooked it up to my Cisco 7960 - Instant wireless VOIP, anywhere in the world 802.11 access is available.

  • This is cool... (Score:5, Interesting)

    by dealsites ( 746817 ) on Wednesday November 03, 2004 @09:55PM (#10718952) Homepage
    Be sure to check out this article [pbs.org] on a sweet Asterisk implementation.
    --
    Watch this page for Black Friday Information! [dealsites.net]

  • Useful Asterisk Resources (Score:5, Informative)

    by TheMysteriousFuture ( 707972 ) * <TheMysteriousFutureNO@SPAMgmail.com> on Wednesday November 03, 2004 @09:58PM (#10718970) Journal
    Useful Asterisk Links:

    The Asterisk Wiki [voip-info.org]
    Note: the wiki search is useless. Search with google instead, use "searchterm site:voip-info.org" (without quotes).

    The Asterisk Documentation Project [asteriskdocs.org]

    The Asterisk Mailing Lists [digium.com]
    Note: to search the lists use google again. "searchterm site:lists.digium.com" (without quotes)" in google.

    the #asterisk chat room on irc.freenode.org. Drop by and say hello.
    Note that due to problems with massive spambot attacks regisitration is required to join the channel. Simply type
    /msg nickserv register mypassword
    /join #asterisk

    The next time you join you will need to type
    /msg nickserv identify mypassword

  • Whoa! (Score:4, Funny)

    by cmcguffin ( 156798 ) on Wednesday November 03, 2004 @09:59PM (#10718972)
    I had no idea Asterix [ifi.uio.no] was a linux geek!

  • Our solution (Score:5, Interesting)

    by frankthechicken ( 607647 ) on Wednesday November 03, 2004 @10:11PM (#10719066) Journal
    At my office we all have our own x-boxes, and using the X-box live service, we are able to happily communicate with each other at a very competetive pricing structure.

    The solution offers a simple text messaging scheme, and conference calling facillities.

    I can fully recommend this solution to any businesses looking for a cost effective VoIP.
    • we just use skype.
      we already have a computer, no sense in getting another.
      • we just use skype

        Actually, so do we, I was trying to make a little joke, which appears to have been taken seriously.

        I liked the idea of people talking wearing their "Xbox communicator" headsets whilst using the gamepad to furiously tap messages to each other.

        But if some people find it interesting, maybe there is some, small, tiny merit in the idea.
    • ha.

      HAHA..

      HAHAHHAHAHABAHA
      BWHAHAHAHHAHAH HAH A AHHAH AHH AHHAH AHAH HAHA HAH AH A

      You CAN'T be serious. XBOX LIVE? for a BUSINESS VOIP SOLUTION? BWHHAHHAHAHAHAH that's the best thing I've heard all day. Thanks for the laugh.

      HAHAHAHAH

      Now if you are a 2 man operation that might work okay if you don't ever take customer calls. But
      How do you have:
      Call Queues
      Music On Hold
      Find Me Follow Me
      Voicemail
      Transfering
      et al

      with xbox live.
      • Now you'll really be laughing in a week when the /. post about someone porting this to xbox linux comes in.
        • It's already been done. Asterisk runs fine on xebian and Gentoox. You can use USB FXS adapters to connect phones. If you google there is even a video from a conference where it was demo'ed.

          Running Asterisk on a xbox has absolutely nothing to do with using xbox live and saying it's a viable solution for small business.
    • I bet you have no problems maintaining productivity levels with an X-box on everybody's desks...
  • Gentoo has the ebuild information here [gentoo.org]

    And if your a hardcore BSD person... check out this page about Asterisk on BSD [digium.com]

    Hum... much like the senior citizens [funwavs.com]... Gentoo and BSD may serve a purpose.

  • A view from the industry (Score:5, Insightful)

    by jaymzter ( 452402 ) on Wednesday November 03, 2004 @10:31PM (#10719190) Homepage
    From an enterprise viewpoint, that is a very large service base, asterisk is dead in the water until it can match the simplicity of the interfaces found on proprietary systems. This isn't a knock on asterisk as a technology solution, but the telcom admin of a large corporation isn't going to want to look at a text file to figure out his dialplan or use some arcane interface when on a more mature system he can use a simple command like 'display dialplan'.
    I don't doubt many people have used asterisk as a voice solution for some companies, but not for any major companies and certainly not for any huge call centers. RTFA, a CIO would sh*t if you showed him snippets from some text file. Not to mention the questionable logic of running your voice system on a white box computer. It may be fine and dandy when e-mail is down for an hour, but five minutes without phones is a lifetime for any serious company. 5 9's is not a joke in the voice world and actually a rational expectation.
    In other words, I support asterisk simply because I love open source, but don't kid yourself, right now it's just a hobby app (as seen from the enterprise)

    • Re:A view from the industry (Score:5, Informative)

      by LittleLebowskiUrbanA ( 619114 ) on Wednesday November 03, 2004 @10:35PM (#10719216) Homepage Journal
      " the simplicity of the interfaces found on proprietary systems"

      Apparently you've never used Avaya IP Office. I YEARN for the simplicity of text files. 3 freaking different GUIs to manage it and they're interconnected but you have to change things using at least 2 of them in many places.

      • Re:A view from the industry (Score:3, Interesting)

        by DLG ( 14172 )
        Likewise, as primary network and telephony guru at my firm, my Cisco CallManager based system, despite being primarily LDAP and SQL based as far as configuration is concerned (except of course where we are using H323 at gateways instead of MGCP) the interfaces necessary for the creation and move-add-changes of users is grueling. It makes me what to develop my own front end, ut of course if I start writing to their databases my support would go out of the window.

        Its easy to build pretty GUI's over configura
      • IP Office isn't for large sites, which is what my post referred to. Not to down you, but you apparently have never used a Nortel or Avaya PBX designed for thousands of users, then you'd know what I was referring to. It's drop dead simple to configure them, until you get into the heavy call center features, that is.
        And yeah, IP Office is a joke
        • Very true about the large sites.

          I have problems getting free support (forums, mailins lists, docs, etc..) for IP Office and am starting to realize that I'm locked into Avaya and their local vendor for everything. Is that the case with the larger PBXs from Avaya?
    • "the telcom admin of a large corporation isn't going to want to look at a text file to figure out his dialplan or use some arcane interface when on a more mature system he can use a simple command like 'display dialplan'."

      Hmmm.. You know.. you are absolutely right. Using "display dialplan" on a more mature solution is infinitely easier than using the "show dialplan" command that is found in Asterisk.

      asterisk*CLI> help show dialplan
      Usage: show dialplan [exten@][context]
      Show dialplan

      NEXT!
      • Ok, I'll take next! 'change dialplan', versus what exactly in asterisk? No need to respond, I've read their convoluted explanation of their concept of a dialplan.
        All that aside however, this isn't about knocking asterisk! I compared it to a Large Enterprise, and stated the obvious, that's all
    • Valid comments about making config and changes. I come from the days when all configuration was routinely done at a command line man-machine interface. It works fine, but did require training. Today we have solid but totally proprietary (and expensive) web or PC based graphical configuration systems, often requiring a separate PC just for programming.

      A Webadmin type interface for Asterix would go a long ways toward making the product more acceptable to end users.

      As for uptime, telco CO switches and PBX's,
    • Please.. PLEASE.. tell me what enterprise PBX system it is you have that has this wonderful user friendly interface?

      Because form the ones I've had to use, I can tell you, I'll get far more flexibility and power out of asterisk than most commercial PBX systems I've seen.

      BTW, if it's such a "hobby" app, why is it that some extremely large VOIP providers use it? Serious businesses, too..

      • Re:Are you joking? (Score:2, Informative)

        by jaymzter ( 452402 )
        Both Nortel and Avaya PBXs have command line driven user interfaces, which is what I'm referring to. That in itself is only a surface similarity to asterisk. While both are CLI based, the proprietary ones are built not only on simple to recall commands, but it's the TEXT interface where all you have to do is fill out the proper fields that makes them better IMO. asterisk just gives you a blank line. Welcome to your first Linux install. It's the difference between doing 'make oldconfig' and 'make menuconfig'
        • Because you mentionend "the cio would not like text files for config".

          THe type of differences you are talking about would not even be noticed by a Cio/cfo/whatever.

          a CLI (which asterisk has, by the way) is not significantly different than editing text. Further, text files often give you a clearer picture of what's going on than a simple command line.

    • my understanding is that Vonage uses the voice mail code in Asterix
    • >but the telcom admin of a large corporation isn't going to want to look at a text file to figure out his dialplan or use some arcane interface >when on a more mature system he can use a simple command like 'display dialplan'.

      except, 'show dialplan' already works in the asterisk cli, I just typed it a couple of hours ago.

      >Not to mention the questionable logic of running your voice system on a white box computer.

      Netfinity's are cheap on Ebay, I just got one for $400 Cdn 4 way Xeon w/ 4 gig
    • I can speak from experience on this. I work for a company that provides IT services for small companies. We implemented Cisco Callmanager at one of our clients and Asterisk at another. The client running CallManager has about 200 employees and when all was said and done cost about $250k (2 Call Managers, Unity, IPCC, router, switches, 7940s & 7960s). The client running Asterisk has about 15 employees and when all was said and done the cost was about $1000 (Asterisk on a Dell, Digium card, Handytone phon
      • how did you get it down to $1000? I ask because my company is doing several phone systems for small businesses these days and to get the price down we've been using referbed legacy systems, but they are a bit of pain and lack some functionaliy, but when looking at this after reading this article I've found the cards run around $500 and even if you use the cheapest computer you can find (not a good idea in my opinion) it's still $399 or so that doesn't leave much room for phones, which is what always eats yo
    • I'm in the industry also, and I don't understand why Asterisk couldn't be an enterprise-grade application. Sensis here in Australia (one of the largest unified web/voice service centers in the country) runs on a proprietary soft PABX, which is a Windows-based solution. While the unified messaging capabilities and user interfaces are a bit more developed, the hardware on which they run is the same. It costs much less to build a fully redundant data server than it does a fully redundant proprietary voice serv
    • Actually, it's fairly uncommon at large companies for the CIO to give a damn about how the thing is configured... that's your problem, Slashbot. Similarly, they wil indeed sh*t if they find it's running on a white box computer... but the choice of platform is your problem, not the software's.

      I'm not disagreeing with you about Asterix's readiness or lack thereof, I don't really have an opinion. But I do have a lot of experience with CIOs going through the buying process, and I can tell you that they think i
      • White box hardware in a mission critical solution stinks to high heaven, but an open source app on good gear with a clear set of contingency and support plans has a fighting chance these days

        You're right! about a year ago, I convinced the IT Director to implement Plone as a company intranet (instead of Sharepoint or Oracle Portal). I got a nice, brand-name, rackmount server. Installed RH9, created a tested recovery plan and nightly backups scripted in cron. Works great and it's been a big success, which i

    • *SIGH*. You don't like the text file configs for asterisk? Then contribute to one of the several Asterisk GUI projects. Or better yet spend some of the cash you would have paid for that Avaya or Cisco system to sponsor some developers to write a PHB style GUI.

      Also here is what MOST people don't understand.
      There really isn't any reason for people to develop (and release for free) a comprehensive GUI for Asterisk, and here's why.

      Most of the people who contribute to Asterisk do Asterisk consulting (some full
    • >but the telcom admin of a large corporation isn't going to want to look at a text file to figure out his dialplan or use some arcane interface
      As with most things Linux, the install problems usually get simplier through heavy use.

      I tried installing asterisk 18 months ago, and wasn't getting their, not much like http://voip-info.org/wiki-Asterisk [voip-info.org] that I could find then, not much hardware in the market place...

      3 weeks ago, I tried again, succesfully. 10* better. now dozens of voip phones, and config sc
    • 5 9's is not a joke in the voice world and actually a rational expectation.


      Well, it is usually a decimal expression, but could always be re-written:
      99999
      ------
      100000
      -Peter
    • Thats funny. From the asterisk cli prompt I can type in "show dialplan", and it displays the dialplan.
    • You need to read a little before spouting off there, maverick: [code] pbxMobile*CLI> help show dialplan Usage: show dialplan [exten@][context] Show dialplan pbxMobile*CLI> [/code] Asterisk has a VERY easy interface to grok a VOIP PBX

  • So what? (Score:1)

    by Anonymous Coward
    We've been doing this with 3com NBX equipment and IPcop VPNs for years. Works great.

  • Is Asterisk Ready for Home Users? (Score:5, Interesting)

    by PetoskeyGuy ( 648788 ) on Wednesday November 03, 2004 @11:03PM (#10719380)
    I have two incoming phone lines here. Is a PBX like Asterisk only cost-effective for office environments where they are paying thousands per month for bandwidth, or can this also be used to replace my current 2 line POTS setup?

    I have some spare computers, and would love the add voice mail, caller id, etc. Just wondering about keeping my existing phone numbers and monthly costs. When would I break even?

    • I'm pretty new to the whole concept, but it looks like for a whopping $99.95, you can get One of these [yahoo.com] to build yourself a home software PBX on a POTS line. My ignorant assumption, though, is that it just acts as a phone-call router for your existing phone numbers in this case, but I'm sure someone will correct me if I'm wrong.

      • That's an FXO card which hooks up to a standard pots line. You would also need a voip phone or an FXS card which you can plug a standard phone into. For a home system you don't realy need a FXO card because it is unlikly that you would want to pay for a pots line to route local calls.

        CP
        • But you might want to have a POTS line handy for when the power goes out for more than a few hours.

          I lost power during $hurricane_name for anywhere from not at all to nearly two days,a nd I got it easy. My phone worked the /whole time/.

          • I haven't had a pots line in seven years, but I guess if you wanted one you could write a dialplan to route 911 and local calls over the FXO card. BTW the card mentioned in the inital post has a "pass through" port which the pots line can pass through even with the asterisk box off. It would be nice to have a pots line for testing but I normaly loop one of my FXS ports back to the FXO port and then route X trafic that way for testing.
      • Actually, this is nothing more than an Intel Ambient winmodem that digium wrote drivers for. Any modem with the same chipset (Ambient MD3200 I believe) should work. I've got an asterisk setup at home with one of these. I used the gentoo ebuild with a modem I got for $20 on ebay. Works great, I have the coolest answering machine on the block.
  • Can it use Speex for audio compresion?
  • What the world needs now, is mobile firewall, sweet firewall. It's amazing that we haven't heard of the SMS of Death yet, or Symbian trojans. Where's that PalmOS firewall? Then the phone can be safe for an OpenVPN client.
  • They connected their Asterisk PBX to the PSTN through a $500 card to a T1. How can I connect my Asterisk to my cablemodem (3/0.5Mbps)? What does it connect to over the WAN to complete calls to the global PSTN? Is it 100% reliable, with a complete footprint in urban areas, and failover to the rest of the POTS phones in the world?

    • Re:Consumer broadband? (Score:4, Interesting)

      by DA-MAN ( 17442 ) on Wednesday November 03, 2004 @11:57PM (#10719834) Homepage
      They connected their Asterisk PBX to the PSTN through a $500 card to a T1. How can I connect my Asterisk to my cablemodem (3/0.5Mbps)? What does it connect to over the WAN to complete calls to the global PSTN? Is it 100% reliable, with a complete footprint in urban areas, and failover to the rest of the POTS phones in the world?

      Simple, use ethernet and get a voip provider instead of using a PSTN T1. I currently use http://connect.voicepulse.com/ [voicepulse.com], and that works great for me. Pretty cool, because you can have multiple incoming calls over one connection.

  • limited budget indeed (Score:5, Insightful)

    by SuperBanana ( 662181 ) on Wednesday November 03, 2004 @11:31PM (#10719661)

    I purchased three Intel white-box computers for $800 each containing 2.6Ghz processors 512MB ram and 40 GB hard drives

    Anyone who recommends greybox PCs with non-raid storage for a financial institution...even a small one with only three branches...is not thinking very clearly. If it's for a business-critical application like the phone system, they're categorically insane.

    Folks- there's a reason those telco boxes cost lots of dough. They Just Work if they're left alone (in 7-8 years of working with telco equipment, 99% of the problems have been telco line provider problems; hardware failures are extremely rare). There are books upon books written with guidelines for what is considered telco grade, but the common theme is "keeps going, and if it breaks, it does so gracefully".

    $2500 can, even for a small bank, be PENNIES ON THE DOLLAR when the system goes down for even a few hours. If you've got a Lucent phone system and a support contract, they find stuff before you do, and no matter what time of day- there's a tech on your doorstep in an hour if they can't remote in via the system's POTS admin modem.

    You want a cheap phone system, you get what you pay for. It's remarkably irresponsible for the authors of that article to advocate Asterisk without mentioning that reliability and support pale in comparison to 'real' telco equipment.

    • You obviously missed the part where it said buying _multiple_ backup machines, and you'd still save money. People, can we read the article.

    • Re:limited budget indeed (Score:1, Insightful)

      by Anonymous Coward
      While the authors were remiss in suggesting the systems they did there is no reason why an Asterisk based system can not be built with the redundancy and scaleability of a "real telco solution". Telcos and large suppliers have a vested interest in making telephony seem more difficult then it is, and frankly the cat is out of the bag. It is very possible to build a system with a very high level of reliability for a fraction of the cost of a commercial system. I've had a lucent phone system and a support cont
    • There's a company [google.com] that banks their proven reliability on the redundancy of their software. Not hardware.

      I think they are doing pretty good.
  • Where's the security? This doesn't do anything to secure the connection. It's just a PBX on a PC.

    If it did end-to-end encryption with suitable handsets, that would be useful.

  • I'm trying to understand the complete business cycle

    Let's say a small voip for residential similar to vonage.

    It's easy to understand voip when it's ip to ip but I get confused when it's ip to pstn.

    Do I need an asterisk box or something similar in each area code that I want to provide service? How do I purchase the numbers for the area code's I want? If I want to have say 1000 lines at first for my customer pool do I actually need 1000 individual rj11 lines? Or do these t1 lines thingie's merge a bunch
    • If you want to do SIP/IAX you only need a network card, no fancy $500 T1 cards..You can purchase DID's ( Direct Inward Dial ) from NuFone.net or connect.voicepulse.com to work with Asterisk. They give you a "virtual number" from whatever state you want. You can have multiple calls on the single DID. Basicly you put a statement in your IAX configuration file to register with either of the services ( after signing up with them ) and when you register it tells them what IP address your Asterisk server is to ro
      • Hmm, what I meant was if I wanted to startup a residential voip service for example. Do I need asterisk boxes in each area where i want to purchase area codes? I'm looking at a complete solution and not relying on nufone or what have you. What I'm basically asking is how does vonage do it? Do they 'need' to have offices in each city where they want to provide service? I assume they over sell. What's a normal line to customer ratio? Basically I want to understand the complete cycle of how voip works f
  • after reading some of the posts about this i can only say, man you people are spoiled! ;-) Last time i was anywhere near telco equipment in a big financial institute they still had 386's running the damn stuff ( this was Australia, u know what i'm sayin if you know about telstra/optus ), the comm's guy asked me if we had something else to put the software on and put some cards in, i suggested a nice P3 and he chocked and said it was too new, i ended up giving him an old pentium 66 or the like and he was c

  • Asterisk is our backup (Score:3, Interesting)

    by ashitaka ( 27544 ) on Thursday November 04, 2004 @12:57AM (#10720277) Homepage
    We have an 18-year old ROLM 9751 switch that thinks it's the year A4. Our voicemail is Octel running on OS/2 that thinks it's the year 104.

    The old telecom equipment is generally rock solid but if it dies it will take time to fix even under contract. The last time we had a card die we were without phone service for a full day as they had to Fedex a replacement from Toronto to Vancouver.

    As a backup against a catastrophic failure of the switch and/or voicemail I've set up an asterix box pre-configured with all the extensions and trunks.
    Switching to a complete VOIP setup using softphones at the start and adding VOIP handsets as they can be obtained could have us up with a complete PBX within 2-3 hours.

  • Trans-Atlantic VoIP (Score:4, Insightful)

    by Evanrude ( 21624 ) <david@fattycCOUGARo.org minus cat> on Thursday November 04, 2004 @01:35AM (#10720474) Homepage Journal
    A friend of mine, who works for a UK telecom and my company, Axigent [axigent.net], have setup a connection between our two asterisk systems that has proven fairly reliable and "secure". I would say with everything we've gone through to make the connection functional, the author of this column left out a lot of the details as far as full implementation of an Asterisk PBX. A helpful site, or at least one of the more helpful sites I've come across is the wiki at www.voip-info.org, which the author neglected to reference in his article. Knowing someone that works at a Telecom is a plus, I think the cost from both ends as far as equipment has been fairly minimal and the return on the time invested as far as learning what VoIP is capable of has been huge. All of the calls that are made back and forth have been clear. It's pretty impressive to call overseas at no charge.

  • asterisk daily news (Score:1, Informative)

    by Anonymous Coward
    news asterisk daily [sineapps.com]
    asterisk news [sineapps.com]
    asterisk daily news [sineapps.com]

    Please don't mod below 0...trying to google bomb to move this awesome site up a bit.

  • Asterisk Versatility (Score:2, Informative)

    by visionik ( 63503 )
    I've started to use Asterisk for various applications, including as a

    - PSTN to VOIP gateway: combine a cheap server, asterisk, and a few $50 voicemodem cards and you've got a VOIP gateway that can connect your outside phone lines to any VOIP phone.

    - VOIP to PSTN gateway: cheap server, asterisk, open VOIP provider like VoicePulse Connect [voicepulse.com], and some Digium FXS cards [digium.com] and you can connect every phone in your house to a VOIP network.

    - PSTN/VOIP front-end to IVR gateway: cheap server, Asterisk, IVR [voxeo.com] provider like
  • We have an easy and simple installer under the name of Xorcom Rapid. It installs Debian and Asterisk from scratch (while destroying everything else on your computer). It is available for (free) download at: www.xorcom.com

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