mgraves@mstvp.com
2004-Nov-03 08:13 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
This week marks one year since I first setup an Asterisk server in the hopes of transitioning my home office to a total VoIP system. The process has been an incredible learning experience. I've tried numerous IP hard phones, eventually settling upon the Polycom IP600 as my choice. I've also used multiple ATAs including all the Sipura products. Using Asterisk has been a challenge, a thrill and (when its working) a joy. However, the one thing that I am not satisfied with is the performance of the FXO interfaces that bring in my PSTN lines. I've tried X100p cards but found them horribly unreliable. I presently use Sipura SPA-3000s but they're only marginally better. How is it that my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four stable, reliable FXOs with no echo at all in a device with a total cost of <$500? It seems to me that there ought to be hardware available that behaves just as well, but bridges the PSTN to the SIP/IAX domain? I've read a lot on the list about how difficult designing FXOs can be, but that flies in the face of the fact that every small multi-line phone system has them...and without expection those behave better than the devices I've been able to try with Asterisk. The Sipura SPA-3000 has several settings to adjust for line impedance and inductive/capacitive line loading....lots of settings, but it provides nowhere near the basic performance of one of the lines on the Panasonic KSU. It's simply mind boggling. So, while I've posted with respect to FXOs previously, I must ask again....what FXO interface device can anyone recommend from real experience? Michael P.S. - I even investigated switching my lines to ISDN to get around the need for FXOs, but SBC won't do it where I live. -- Michael Graves mgraves@pixelpower.com Sr. Product Specialist www.pixelpower.com Pixel Power Inc. mgraves@mstvp.com o713-861-4005 o800-905-6412 c713-201-1262
> This week marks one year since I first setup an Asterisk server in the > hopes of transitioning my home office to a total VoIP system. The > process has been an incredible learning experience. I've tried numerous > IP hard phones, eventually settling upon the Polycom IP600 as my > choice. I've also used multiple ATAs including all the Sipura products. > Using Asterisk has been a challenge, a thrill and (when its working) a > joy. However, the one thing that I am not satisfied with is the > performance of the FXO interfaces that bring in my PSTN lines. > > I've tried X100p cards but found them horribly unreliable. I presently > use Sipura SPA-3000s but they're only marginally better. How is it that > my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four > stable, reliable FXOs with no echo at all in a device with a total cost > of <$500? It seems to me that there ought to be hardware available that > behaves just as well, but bridges the PSTN to the SIP/IAX domain? > > I've read a lot on the list about how difficult designing FXOs can be, > but that flies in the face of the fact that every small multi-line > phone system has them...and without expection those behave better than > the devices I've been able to try with Asterisk. The Sipura SPA-3000 > has several settings to adjust for line impedance and > inductive/capacitive line loading....lots of settings, but it provides > nowhere near the basic performance of one of the lines on the Panasonic > KSU. It's simply mind boggling. > > So, while I've posted with respect to FXOs previously, I must ask > again....what FXO interface device can anyone recommend from real > experience?I'd have to agree with you 110%; exactly the same issues here over the past year. I've spent more money on digium cards then you have invested in your old system, tried the spa3000, and a few other external gateways. The external gateways are always far better then the digium/spa adapters, but most of them have other issues that preclude production use. The market space is absolutely wide open for a two-to-four port pstn adapter of some sort that actually works. As I'm sure you've seen over the last six months or so, the digium fxo cards (drivers) suffer from lots of different problems and no one seems to really care. As a non-programmer, I'm about to give up on those as I don't have the skills to attempt fixes, and opening bug reports seem to be totally ignored. Seems at least some of the issues relate to interrupt latency and/or pci controller problems with selected motherboards, however there hasn't been any realistic effort focused on identifying which boards are acceptable/unacceptable. Seems rather strange for a company that wants to finance the * project through sales of adapters to ignore the problems, but guess that's their call. Rich
Dave Henderson
2004-Nov-03 08:23 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
Hi Michael, You mention the X100P -- I agree, it's not a great card. I've had all sorts of issues with mine, though I've lived with it for one of my not-so-important Asterisk PBXes. One device it seems you haven't tried is the Digium TDM400P with an FXO module... I've used a pile of these, and have generally been very pleased with them. -- Dave Henderson Customer Service Manager The IT Department, Inc. -----Original Message----- From: asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of mgraves@mstvp.com Sent: November 3, 2004 10:14 AM To: Asterisk Group Subject: [Asterisk-Users] An anniversary and a lament for FXOs This week marks one year since I first setup an Asterisk server in the hopes of transitioning my home office to a total VoIP system. The process has been an incredible learning experience. I've tried numerous IP hard phones, eventually settling upon the Polycom IP600 as my choice. I've also used multiple ATAs including all the Sipura products. Using Asterisk has been a challenge, a thrill and (when its working) a joy. However, the one thing that I am not satisfied with is the performance of the FXO interfaces that bring in my PSTN lines. I've tried X100p cards but found them horribly unreliable. I presently use Sipura SPA-3000s but they're only marginally better. How is it that my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four stable, reliable FXOs with no echo at all in a device with a total cost of <$500? It seems to me that there ought to be hardware available that behaves just as well, but bridges the PSTN to the SIP/IAX domain? I've read a lot on the list about how difficult designing FXOs can be, but that flies in the face of the fact that every small multi-line phone system has them...and without expection those behave better than the devices I've been able to try with Asterisk. The Sipura SPA-3000 has several settings to adjust for line impedance and inductive/capacitive line loading....lots of settings, but it provides nowhere near the basic performance of one of the lines on the Panasonic KSU. It's simply mind boggling. So, while I've posted with respect to FXOs previously, I must ask again....what FXO interface device can anyone recommend from real experience? Michael P.S. - I even investigated switching my lines to ISDN to get around the need for FXOs, but SBC won't do it where I live. -- Michael Graves mgraves@pixelpower.com Sr. Product Specialist www.pixelpower.com Pixel Power Inc. mgraves@mstvp.com o713-861-4005 o800-905-6412 c713-201-1262 _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Robinson Tim-W10277
2004-Nov-03 08:29 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
Michael The problem lies not with Asterisk or the cards but with the combination of voip and analogue telephony in general. I can guarantee that you will have very similar echo when you connect your Panasonic pbx to the analogue lines. In fact, your echo will most likely be worse. It is just that you do not perceive it as echo because it occurs more or less coincident with the original sound. However, the propagation delay through the systems that is introduced by Asterisk and voip (by necessity and design) is the culprit, because this adds the delay which causes the echo to become perceptable. You will never get a match good enough to eliminate echo. What you may be able to do is to get a match that is good enough to allow the built-in echo cancellers to be effective. You don't say where you hear the echo - near end or far end? A small diagram of your system posted on your web site, with an indication of who hears the echo and which echo they are hearing would help me (or countless others!) to help you work this out. I am using 2 X100P cards here in the UK connected to extension ports of a Panasonic KXT616 and we get no perceptable echo at all. Good luck! Rgds Tim Robinson -----Original Message----- From: asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of mgraves@mstvp.com Sent: 03 November 2004 15:14 To: Asterisk Group Subject: [Asterisk-Users] An anniversary and a lament for FXOs This week marks one year since I first setup an Asterisk server in the hopes of transitioning my home office to a total VoIP system. The process has been an incredible learning experience. I've tried numerous IP hard phones, eventually settling upon the Polycom IP600 as my choice. I've also used multiple ATAs including all the Sipura products. Using Asterisk has been a challenge, a thrill and (when its working) a joy. However, the one thing that I am not satisfied with is the performance of the FXO interfaces that bring in my PSTN lines. I've tried X100p cards but found them horribly unreliable. I presently use Sipura SPA-3000s but they're only marginally better. How is it that my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four stable, reliable FXOs with no echo at all in a device with a total cost of <$500? It seems to me that there ought to be hardware available that behaves just as well, but bridges the PSTN to the SIP/IAX domain? I've read a lot on the list about how difficult designing FXOs can be, but that flies in the face of the fact that every small multi-line phone system has them...and without expection those behave better than the devices I've been able to try with Asterisk. The Sipura SPA-3000 has several settings to adjust for line impedance and inductive/capacitive line loading....lots of settings, but it provides nowhere near the basic performance of one of the lines on the Panasonic KSU. It's simply mind boggling. So, while I've posted with respect to FXOs previously, I must ask again....what FXO interface device can anyone recommend from real experience? Michael P.S. - I even investigated switching my lines to ISDN to get around the need for FXOs, but SBC won't do it where I live. -- Michael Graves mgraves@pixelpower.com Sr. Product Specialist www.pixelpower.com Pixel Power Inc. mgraves@mstvp.com o713-861-4005 o800-905-6412 c713-201-1262 _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Andrew Kohlsmith
2004-Nov-03 08:32 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
On November 3, 2004 10:13 am, mgraves@mstvp.com wrote:> use Sipura SPA-3000s but they're only marginally better. How is it that > my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four > stable, reliable FXOs with no echo at all in a device with a total cost > of <$500? It seems to me that there ought to be hardware available that > behaves just as well, but bridges the PSTN to the SIP/IAX domain?VOIP introduces latencies that Just Do Not Exist in non-VOIP scenarios. I would have thought that after a year with Asterisk you would have come to that conclusion.> I've read a lot on the list about how difficult designing FXOs can be, > but that flies in the face of the fact that every small multi-line > phone system has them...and without expection those behave better than > the devices I've been able to try with Asterisk. The Sipura SPA-3000 > has several settings to adjust for line impedance and > inductive/capacitive line loading....lots of settings, but it provides > nowhere near the basic performance of one of the lines on the Panasonic > KSU. It's simply mind boggling.You're tuning the hybrid; the problem lies in the additional latency incurred with VOIP -- If you took the Panasonic system hardware and VOIP'd it you would likely see similar issues that you see with the X100P, TDM400P and even channel banks. You need a good stable and performance system to get good VOIP quality. There is no substitute. Case in point: I was running an X100P and a TDM410P in a P90MMX -- VOIP calls were pretty good but anything over the POTS was kind of shitty... put the exact same hardware into a P3-700 and the POTS problems went away for the most part.> So, while I've posted with respect to FXOs previously, I must ask > again....what FXO interface device can anyone recommend from real > experience?Personal preference: T100P and a channel bank. Excellent-quality hybrids and a good, solid computer interface. It's about double the cost of your Panasonic system, though, but can handle 24 lines instead of 4. -A.
POTS Lines are analog, and a key system is the best way to deal with analog lines since you are simply switching the voice path with no analog to digital to analog conversion in the process. VoIP is digital, so starting with a digital signal is always the better way to go. Consider the conversion that must take place on a POTS interface Caller speaks into phone - analog signal Call reaches Telco CO - converted to digital for switching on the PSTN Call routed to your POTS line - converted back to analog - no need on ISDN Call answered by * - back to digital - no need on ISDN Call router to your hard phone - back to analog 5 A/D D/A conversions, with lossy compression along the way (VoIP) Also, digital service provides rock solid and predictable signaling for call starts, ends, CID, etc. POTS lines provide shady analog signaling the is hard to interpret because of line quality variations. So unless you can get really clean POTS lines you are far better off with ISDN/PRI, and if you cant get that a key system with an analog voice path will sound better, always. I realize this does not answer your question and solve the problem, it is just an attempt to explain why you are not getting a better answer. I would assume MOST * deployments will be in environments where nothing but T1/E1 would ever be considered, leaving the SOHO user in the same position they are in now, spend more or live with the limitations. With all that being said, start by checking your POTS lines (or asking the Telco to) for excessive resistance, impedance and noise. The fact that you are not having good experiences with a variety of hardware where others have been able to get good (acceptable) results indicates there may be a line issue. Damon (new to * but not new to Telecom and VoIP) -----Original Message----- From: asterisk-users-bounces@lists.digium.com [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of mgraves@mstvp.com Sent: Wednesday, November 03, 2004 8:14 AM To: Asterisk Group Subject: [Asterisk-Users] An anniversary and a lament for FXOs This week marks one year since I first setup an Asterisk server in the hopes of transitioning my home office to a total VoIP system. The process has been an incredible learning experience. I've tried numerous IP hard phones, eventually settling upon the Polycom IP600 as my choice. I've also used multiple ATAs including all the Sipura products. Using Asterisk has been a challenge, a thrill and (when its working) a joy. However, the one thing that I am not satisfied with is the performance of the FXO interfaces that bring in my PSTN lines. I've tried X100p cards but found them horribly unreliable. I presently use Sipura SPA-3000s but they're only marginally better. How is it that my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four stable, reliable FXOs with no echo at all in a device with a total cost of <$500? It seems to me that there ought to be hardware available that behaves just as well, but bridges the PSTN to the SIP/IAX domain? I've read a lot on the list about how difficult designing FXOs can be, but that flies in the face of the fact that every small multi-line phone system has them...and without expection those behave better than the devices I've been able to try with Asterisk. The Sipura SPA-3000 has several settings to adjust for line impedance and inductive/capacitive line loading....lots of settings, but it provides nowhere near the basic performance of one of the lines on the Panasonic KSU. It's simply mind boggling. So, while I've posted with respect to FXOs previously, I must ask again....what FXO interface device can anyone recommend from real experience? Michael P.S. - I even investigated switching my lines to ISDN to get around the need for FXOs, but SBC won't do it where I live. -- Michael Graves mgraves@pixelpower.com Sr. Product Specialist www.pixelpower.com Pixel Power Inc. mgraves@mstvp.com o713-861-4005 o800-905-6412 c713-201-1262 _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Wilson Pickett
2004-Nov-03 09:41 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
> This week marks one year since I first setup an Asterisk server in the > hopes of transitioning my home office to a total VoIP system.I have only been doing it since May> I've tried X100p cards but found them horribly unreliable.The reason I'm answering is to weigh in with the fact that I have a SOHO system running with two POTS lines connected to two X100P cards, three FXS through the TDM400P. The cards are sitting in a PIII-800 Asus mobo with 512MB RAM. Everyone is talking about voIP, but within the office (FXO<-->FXS), we have no echo, only if going out to SIP or IAX is there any and it usually is only in the very first part of a call. The person who mentioned rxgain and txgain certainly has a good point, I think that's very important to get right. I suppose I should consider us lucky that things work well, but I also know that the Slackware box I use has nothing unnecessary running and no "extra" cards using any IRQ. I used to do a lot of digital audio recording and in those days, a lot of people on the forum discussed video adapters as the cause of a lot of interference. Those of you who may read this and think "I wanna try asterisk": if you plan to build a box from spare parts as I did, try a few different cards. I don't even have X set up in the asterisk box, just the basic OS, Apache and mysql (which I don't currently run or use, but it's there.) Even Apache isn't started on boot, only if I want to use it for the manager. My own observation of 6 months of this is that the hardware is certainly NOT "plug and play", I'd say many, many people have had problems with both the X100 and the TDM400 cards in the beginning. The TDM did give me trouble at first, but it was apparently IRQ issues that got solved with a little experimentation.
Dave Henderson
2004-Nov-03 09:44 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
Hi Rich, I've had good success with the cards in HP ProLiant ML110 servers, as well as on clones with Asus P4C800-E motherboards. I believe the chipset on both of these systems is the Intel 875/ICH5... FYI, I'm not in the US -- I'm in Canada. But that doesn't make a difference as far as PSTN signalling goes. HTH -- Dave Henderson Customer Service Manager The IT Department, Inc. -----Original Message----- From: Rich Adamson [mailto:radamson@routers.com] Sent: November 3, 2004 10:33 AM To: Dave Henderson Subject: RE: [Asterisk-Users] An anniversary and a lament for FXOs Hi Dave, Any chance that you could pass along some of the specific system and/or motherboard model numbers that work with the tdm card? I'm in the same boat as Michael, and have tried the x100p's, tdm04b, spa3k, mediatrix, and others. I'd like to get the tdm04b working in a stable production environment, and based on many previous posts, it would appear to be an issue with interrupt latency and/or pci controller problems with certain motherboards. I'd love to hear some examples that actually work (no echo) in the US. Rich Adamson radamson@routers.com ------------------------> Hi Michael, > > You mention the X100P -- I agree, it's not a great card. I've had all> sorts of issues with mine, though I've lived with it for one of my > not-so-important Asterisk PBXes. > > One device it seems you haven't tried is the Digium TDM400P with an > FXO module... I've used a pile of these, and have generally been very> pleased with them. > > -- > Dave Henderson > Customer Service Manager > The IT Department, Inc. > > -----Original Message----- > From: asterisk-users-bounces@lists.digium.com > [mailto:asterisk-users-bounces@lists.digium.com] On Behalf Of > mgraves@mstvp.com > Sent: November 3, 2004 10:14 AM > To: Asterisk Group > Subject: [Asterisk-Users] An anniversary and a lament for FXOs > > This week marks one year since I first setup an Asterisk server in the> hopes of transitioning my home office to a total VoIP system. The > process has been an incredible learning experience. I've tried > numerous IP hard phones, eventually settling upon the Polycom IP600 asmy choice.> I've also used multiple ATAs including all the Sipura products. > Using Asterisk has been a challenge, a thrill and (when its working) a> joy. However, the one thing that I am not satisfied with is the > performance of the FXO interfaces that bring in my PSTN lines. > > I've tried X100p cards but found them horribly unreliable. I presently> use Sipura SPA-3000s but they're only marginally better. How is it > that my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four > stable, reliable FXOs with no echo at all in a device with a total > cost of <$500? It seems to me that there ought to be hardware > available that behaves just as well, but bridges the PSTN to theSIP/IAX domain?> > I've read a lot on the list about how difficult designing FXOs can be,> but that flies in the face of the fact that every small multi-line > phone system has them...and without expection those behave better than> the devices I've been able to try with Asterisk. The Sipura SPA-3000 > has several settings to adjust for line impedance and > inductive/capacitive line loading....lots of settings, but it provides> nowhere near the basic performance of one of the lines on the > Panasonic KSU. It's simply mind boggling. > > So, while I've posted with respect to FXOs previously, I must ask > again....what FXO interface device can anyone recommend from real > experience? > > Michael > > P.S. - I even investigated switching my lines to ISDN to get around > the need for FXOs, but SBC won't do it where I live. > -- > Michael Graves mgraves@pixelpower.com > Sr. Product Specialist www.pixelpower.com > Pixel Power Inc. mgraves@mstvp.com > > o713-861-4005 > o800-905-6412 > c713-201-1262 > > > > > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users---------------End of Original Message-----------------
steve@daviesfam.org
2004-Nov-03 12:49 UTC
[Asterisk-Users] An anniversary and a lament for FXOs
On Wed, 3 Nov 2004 mgraves@mstvp.com wrote:> I've tried X100p cards but found them horribly unreliable. I presently > use Sipura SPA-3000s but they're only marginally better. How is it that > my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four > stable, reliable FXOs with no echo at all in a device with a total cost > of <$500? It seems to me that there ought to be hardware available that > behaves just as well, but bridges the PSTN to the SIP/IAX domain?Your Pana system probably doesn't do any echo cancellation at all. But it doesn't add delay, so you don't notice. Steve
I have been quite successful and pleased with the quality of the Cisco MC3810 and *. I have a single X100p not as an FXO but only as a timing source for conferencing and other apps that require a zaptel timer. No echo and good quality. Jojo ________________________________ From: asterisk-users-bounces@lists.digium.com on behalf of steve@daviesfam.org Sent: Wed 11/3/2004 11:49 AM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: Re: [Asterisk-Users] An anniversary and a lament for FXOs On Wed, 3 Nov 2004 mgraves@mstvp.com wrote:> I've tried X100p cards but found them horribly unreliable. I presently > use Sipura SPA-3000s but they're only marginally better. How is it that > my Panasonic 4 line SOHO phone system (KX-TG4000B) can have four > stable, reliable FXOs with no echo at all in a device with a total cost > of <$500? It seems to me that there ought to be hardware available that > behaves just as well, but bridges the PSTN to the SIP/IAX domain?Your Pana system probably doesn't do any echo cancellation at all. But it doesn't add delay, so you don't notice. Steve _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/ms-tnef Size: 4706 bytes Desc: not available Url : http://lists.digium.com/pipermail/asterisk-users/attachments/20041103/25583af0/attachment.bin