Major deployment of outbound FAX on latest version of Freeswitch question
To Freeswitch developers, RE: MOD_SPANDSP I have a client that wishes to send 20,000 to 30,000 outbound faxes daily and has requested me to quote for a Freeswitch setup that will support this. I notice the comment on the mod spandsp wiki page: "We are finishing mod_spandsp. It requires full field testing now." Well this could be a perfect opportunity :) I need to understand the following: 1. Does the mod spandsp support the TDM cards (Sangoma) to send faxes out over E1 (Euro ISDN)? 2. How many concurrent faxes out have been tested using mod_spandsp ? Was this over SIP or over ISDN? 3. What is the preferred Operating System to use (since basically I would prefer to use the same one as the main developer of mod_spandsp)? 4. Where do I source the latest email2pdf to test that out? That should be enough to kick this question off. Kind Regards, Andrew Keil
Os: CentOs (Recomanded) Sangoma: yes, supported over any protocol. fax is endpoint indepande, could use sangoma card, tdm (FXO/FXS). thank you On 06/05/2011 07:14, Andrew Keil wrote:
To Freeswitch developers,
* *
*RE: MOD_SPANDSP*
I have a client that wishes to send 20,000 to 30,000 outbound faxes daily and has requested me to quote for a Freeswitch setup that will support this.
I notice the comment on the mod spandsp wiki page: "We are finishing mod_spandsp. It requires full field testing now." Well this could be a perfect opportunity J
_I need to understand the following:_
1. Does the mod spandsp support the TDM cards (Sangoma) to send faxes out over E1 (Euro ISDN)?
2. How many concurrent faxes out have been tested using mod_spandsp ? Was this over SIP or over ISDN?
3. What is the preferred Operating System to use (since basically I would prefer to use the same one as the main developer of mod_spandsp)?
4. Where do I source the latest *email2pdf* to test that out?
That should be enough to kick this question off.
Kind Regards,
Andrew Keil
_______________________________________________ FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
-- Meftah Tayeb inum: +883510001288000 phone: +13477595883
On 05/06/2011 01:14 PM, Andrew Keil wrote:
To Freeswitch developers,
**
*RE: MOD_SPANDSP*
I have a client that wishes to send 20,000 to 30,000 outbound faxes daily and has requested me to quote for a Freeswitch setup that will support this.
I notice the comment on the mod spandsp wiki page: “We are finishing mod_spandsp. It requires full field testing now.” Well this could be a perfect opportunity J
_I need to understand the following:_
1.Does the mod spandsp support the TDM cards (Sangoma) to send faxes out over E1 (Euro ISDN)?
2.How many concurrent faxes out have been tested using mod_spandsp ? Was this over SIP or over ISDN?
3.What is the preferred Operating System to use (since basically I would prefer to use the same one as the main developer of mod_spandsp)?
4.Where do I source the latest *email2pdf* to test that out?
That should be enough to kick this question off.
Kind Regards,
Andrew Keil
What is the average number of pages per FAX that you expect to send? Unless its quite big, this will be a fairly small scale system, so you won't need any fancy hardware. You can send the FAXes over ISDN or SIP. The Sangoma cards will do a good job if you want to use ISDN E1s. If the average FAX is <=4 pages, you'll probably only need a single E1, and you won't need anything very exotic for the server, unless you are doing quite a lot of works besides sending the FAXes. If this is a FAX only system you can use an E1 card that does not have an echo canceller (EC) module. That saves money. If you will have voice traffic as well, you had better consider buying an EC equipped card. Centos 5.x is the OS usually recommended for FreeSwitch, as it is what most of the core developers test on. I'm not clear why you are looking for email2pdf. Is this going to be some kind of small scale e-mail to FAX gateway? FAX to e-mail is a more common setup, but quite a few people run e-mail to FAX gateways, too. Steve
Steve, Thanks for your response. Further clarification on my part: 1) 20,000 to 30,000 pages per day to be sent out. 2) It will be an e-mail to fax style gateway (not fax to e-mail since that would involve inbound faxes) 3) The reason I asked about e-mail to PDF is the initial comments from my client requested the ability to send PDFs and WORD documents (I guess from attachments to the original e-mail), I understand the format that gets faxed should be TIFF so I saw on the freeswitch wiki email2pdf mentioned. Then ImageMagick can help get a PDF to TIFF. Can I ask some more questions: Q1) Based on your experience what would be the average time (in seconds) to send a single fax page (TIFF file) via Freeswitch & Sangoma TDM? You can quote a TIFF file size to make it more accurate. From there I should be able to do the math to calculate my Client's requirements better. Q2) Running on CentOS and using mod_spandsp/Freeswitch & Sangoma TDM what percentage CPU usage would I expect to see if 30 concurrent faxes are being sent at the same time (ie. All channels of my E1 are faxing)? (The hardware would be a new 1U rack server from a major hardware vendor) Q3) What version of CentOS 5.x would you recommend? Would the latest version 5.6 be fine? Q4) From memory there used to be different fax quality modes on fax machines (STANDARD, FINE & SUPER FINE or something like that). Is it possible to set the fax send quality from mod_spandsp (also can you provide an example)? If this is the case could you also answer question (Q1) based on the different fax send quality modes. Q5) From exisiting deployments of Freeswitch using mod_spandsp (& Sagoma TDM cards (although this is not critical)) what is the largest number of concurrent outbound faxes done on a single box that you know of? I appreciate your feedback and experience. It sounds like this will work fine with the mod_spandsp/Freeswitch & Sangoma TDM combination on CentOS. I will most likely go for two servers with at least 2 x E1s in each, that way I future proof it a little and add redundancy. Plus my Client can start using Freeswitch for Voice related services also. On my side I can also test faxes going out on the first server and via a cross-over cable I can terminate them on the second server (for testing) - much nicer. Thanks again, Andrew -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Saturday, 7 May 2011 12:58 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Major deployment of outbound FAX on latest version of Freeswitch question On 05/06/2011 01:14 PM, Andrew Keil wrote:
To Freeswitch developers,
**
*RE: MOD_SPANDSP*
I have a client that wishes to send 20,000 to 30,000 outbound faxes daily and has requested me to quote for a Freeswitch setup that will support this.
I notice the comment on the mod spandsp wiki page: "We are finishing mod_spandsp. It requires full field testing now." Well this could be a perfect opportunity J
_I need to understand the following:_
1.Does the mod spandsp support the TDM cards (Sangoma) to send faxes out over E1 (Euro ISDN)?
2.How many concurrent faxes out have been tested using mod_spandsp ? Was this over SIP or over ISDN?
3.What is the preferred Operating System to use (since basically I would prefer to use the same one as the main developer of mod_spandsp)?
4.Where do I source the latest *email2pdf* to test that out?
That should be enough to kick this question off.
Kind Regards,
Andrew Keil
What is the average number of pages per FAX that you expect to send? Unless its quite big, this will be a fairly small scale system, so you won't need any fancy hardware. You can send the FAXes over ISDN or SIP. The Sangoma cards will do a good job if you want to use ISDN E1s. If the average FAX is <=4 pages, you'll probably only need a single E1, and you won't need anything very exotic for the server, unless you are doing quite a lot of works besides sending the FAXes. If this is a FAX only system you can use an E1 card that does not have an echo canceller (EC) module. That saves money. If you will have voice traffic as well, you had better consider buying an EC equipped card. Centos 5.x is the OS usually recommended for FreeSwitch, as it is what most of the core developers test on. I'm not clear why you are looking for email2pdf. Is this going to be some kind of small scale e-mail to FAX gateway? FAX to e-mail is a more common setup, but quite a few people run e-mail to FAX gateways, too. Steve _______________________________________________ FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org __________ Information from ESET NOD32 Antivirus, version of virus signature database 6101 (20110506) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
On 05/07/2011 04:02 AM, Andrew Keil wrote:
Steve,
Thanks for your response.
Further clarification on my part:
1) 20,000 to 30,000 pages per day to be sent out. So, this is fairly small scale. A single E1 will do fine. 2) It will be an e-mail to fax style gateway (not fax to e-mail since that would involve inbound faxes) That covers a few requirements, depending what you expect to be in the e-mails - send the whole e-mail as a FAX; extract a PDF, Word document, etc. from an e-mail, and turn that into a FAX; and so on. 3) The reason I asked about e-mail to PDF is the initial comments from my client requested the ability to send PDFs and WORD documents (I guess from attachments to the original e-mail), I understand the format that gets faxed should be TIFF so I saw on the freeswitch wiki email2pdf mentioned. Then ImageMagick can help get a PDF to TIFF. If the incoming e-mails are limited to ones containing PDFs and doc files to be extracted and turned into FAXes things you seem to have a fairly well defined requirement. OpenOffice can be used to turn the doc files into FAXable images, but I am not clear how well the newer docx files are handled. Ghostscript can be used to turn PDFs into TIFF files.
Avoid ImageMagick for this kind of work. It uses Ghostscript to do the hard work, but it doesn't get the best from it. If you use Ghostscript directly you get better control, and you can achieve good results.
Can I ask some more questions:
Q1) Based on your experience what would be the average time (in seconds) to send a single fax page (TIFF file) via Freeswitch& Sangoma TDM? You can quote a TIFF file size to make it more accurate. From there I should be able to do the math to calculate my Client's requirements better. The time per page depends a lot on its complexity. I use a torture test file with images that take half an hour to send. Typical office work is probably 20s per page at 14400bps. Q2) Running on CentOS and using mod_spandsp/Freeswitch& Sangoma TDM what percentage CPU usage would I expect to see if 30 concurrent faxes are being sent at the same time (ie. All channels of my E1 are faxing)? (The hardware would be a new 1U rack server from a major hardware vendor) The greater part of the CPU load is likely to be what you didn't list there - the processing from e-mail to FAXable TIFF files. A single E1 of FAXing is a really low load these days, though. Q3) What version of CentOS 5.x would you recommend? Would the latest version 5.6 be fine? 5.6 is fine. Q4) From memory there used to be different fax quality modes on fax machines (STANDARD, FINE& SUPER FINE or something like that). Is it possible to set the fax send quality from mod_spandsp (also can you provide an example)? If this is the case could you also answer question (Q1) based on the different fax send quality modes. You can't really set the quality in mod_spandsp. The quality follows the TIFF files to be sent. You can, however, select the image quality as you generate the TIFF files in Ghostscript. STANDARD, FINE and SUPERFINE are the right names, although many machines refuse to use SUPERFINE. Q5) From exisiting deployments of Freeswitch using mod_spandsp (& Sagoma TDM cards (although this is not critical)) what is the largest number of concurrent outbound faxes done on a single box that you know of? I'm not sure of the biggest, but an E1 of FAXing is pretty small volume these days. The biggest number of channels should be in the hundreds. I appreciate your feedback and experience. It sounds like this will work fine with the mod_spandsp/Freeswitch& Sangoma TDM combination on CentOS.
I will most likely go for two servers with at least 2 x E1s in each, that way I future proof it a little and add redundancy. Plus my Client can start using Freeswitch for Voice related services also. On my side I can also test faxes going out on the first server and via a cross-over cable I can terminate them on the second server (for testing) - much nicer.
Thanks again,
Andrew Two servers with one E1 in each sounds like more than enough to meet your needs, unless your 30k pages per day occur over a fairly short working hours, and the customer demands rapid delivery. Then you might need more channels to deal with rush hour.
Steve
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? 2011/5/8 Steve Underwood <steveu@coppice.org>
On 05/07/2011 04:02 AM, Andrew Keil wrote:
Steve,
Thanks for your response.
Further clarification on my part:
1) 20,000 to 30,000 pages per day to be sent out. So, this is fairly small scale. A single E1 will do fine. 2) It will be an e-mail to fax style gateway (not fax to e-mail since that would involve inbound faxes) That covers a few requirements, depending what you expect to be in the e-mails - send the whole e-mail as a FAX; extract a PDF, Word document, etc. from an e-mail, and turn that into a FAX; and so on. 3) The reason I asked about e-mail to PDF is the initial comments from my client requested the ability to send PDFs and WORD documents (I guess from attachments to the original e-mail), I understand the format that gets faxed should be TIFF so I saw on the freeswitch wiki email2pdf mentioned. Then ImageMagick can help get a PDF to TIFF. If the incoming e-mails are limited to ones containing PDFs and doc files to be extracted and turned into FAXes things you seem to have a fairly well defined requirement. OpenOffice can be used to turn the doc files into FAXable images, but I am not clear how well the newer docx files are handled. Ghostscript can be used to turn PDFs into TIFF files.
Avoid ImageMagick for this kind of work. It uses Ghostscript to do the hard work, but it doesn't get the best from it. If you use Ghostscript directly you get better control, and you can achieve good results.
Can I ask some more questions:
Q1) Based on your experience what would be the average time (in seconds) to send a single fax page (TIFF file) via Freeswitch& Sangoma TDM? You can quote a TIFF file size to make it more accurate. From there I should be able to do the math to calculate my Client's requirements better. The time per page depends a lot on its complexity. I use a torture test file with images that take half an hour to send. Typical office work is probably 20s per page at 14400bps. Q2) Running on CentOS and using mod_spandsp/Freeswitch& Sangoma TDM what percentage CPU usage would I expect to see if 30 concurrent faxes are being sent at the same time (ie. All channels of my E1 are faxing)? (The hardware would be a new 1U rack server from a major hardware vendor) The greater part of the CPU load is likely to be what you didn't list there - the processing from e-mail to FAXable TIFF files. A single E1 of FAXing is a really low load these days, though. Q3) What version of CentOS 5.x would you recommend? Would the latest version 5.6 be fine? 5.6 is fine. Q4) From memory there used to be different fax quality modes on fax machines (STANDARD, FINE& SUPER FINE or something like that). Is it possible to set the fax send quality from mod_spandsp (also can you provide an example)? If this is the case could you also answer question (Q1) based on the different fax send quality modes. You can't really set the quality in mod_spandsp. The quality follows the TIFF files to be sent. You can, however, select the image quality as you generate the TIFF files in Ghostscript. STANDARD, FINE and SUPERFINE are the right names, although many machines refuse to use SUPERFINE. Q5) From exisiting deployments of Freeswitch using mod_spandsp (& Sagoma TDM cards (although this is not critical)) what is the largest number of concurrent outbound faxes done on a single box that you know of? I'm not sure of the biggest, but an E1 of FAXing is pretty small volume these days. The biggest number of channels should be in the hundreds. I appreciate your feedback and experience. It sounds like this will work fine with the mod_spandsp/Freeswitch& Sangoma TDM combination on CentOS.
I will most likely go for two servers with at least 2 x E1s in each, that way I future proof it a little and add redundancy. Plus my Client can start using Freeswitch for Voice related services also. On my side I can also test faxes going out on the first server and via a cross-over cable I can terminate them on the second server (for testing) - much nicer.
Thanks again,
Andrew Two servers with one E1 in each sounds like more than enough to meet your needs, unless your 30k pages per day occur over a fairly short working hours, and the customer demands rapid delivery. Then you might need more channels to deal with rush hour.
Steve
_______________________________________________ FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org
On 05/09/2011 01:16 AM, Juan Antonio Ibañez Santorum wrote:
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? The open source options are:
Asterisk + spandsp Asterisk + Hylafax + iaxmodem + spandsp Freeswitch These are all tested and proven to give well below 1% failures, even with quite a lot of concurrent FAX channels in use, if things are set up well. They can give you bad failure rates if things are not set up well. I believe that right now you will have less trouble achieving a reliable setup with Freeswitch. Going forward, most of my effort goes into making the Freeswitch option the most thoroughly implemented one. The main commercial option is: Asterisk + Digium's commercial FAX Of course, there are numerous other fully commercial FAXing options which could be used in conjunction with things like Asterisk or Freeswitch The Digium FAX module is based on the well known Commetrex FAX engine, which is widely deployed, and should be capable of solid results. However, the module is more than just the core FAX engine, and some people do have serious trouble with the module. I have helped moved people off this, and onto Asterisk + spandsp, to improve their reliability. In a couple of those cases people were getting quite a lot of pages cut short when receiving FAXes with T.38, even though a wireshark log showed a perfect exchange, from which I could correctly decode these FAXes. The module was not reporting any errors. In a couple of cases strange machines were sending weird things the Digium FAX didn't cope with very well. I worked with these people to make sure spandsp did handle the weird stuff well, and we ended up with a more usable solution. These people told me that when they complained to Digium they got little help. The best was an offer of a refund. Paying to get some support didn't seem to work out too well for these people, but I guess if the support you are looking for is mostly in getting things configured and working on day one you might get value for money. All these solutions require reliable signaling and reliable media timing, and many people have setups which cannot achieve that. Most people don't understand how things work, and will claim a solution doesn't function for spurious reasons. For example, a number of people say the spandsp module for Asterisk doesn't work, because they keep getting a 488 response. That response has nothing to do with the FAX engine. It is a negotiation error that occurs outside the FAX engine. If they fixed their configuration the error would go away. However, many just move on, having "proven" to themselves the solution doesn't work.
2011/5/8 Steve Underwood <steveu@coppice.org <mailto:steveu@coppice.org>>
On 05/07/2011 04:02 AM, Andrew Keil wrote: > Steve, > > Thanks for your response. > > Further clarification on my part: > > 1) 20,000 to 30,000 pages per day to be sent out. So, this is fairly small scale. A single E1 will do fine. > 2) It will be an e-mail to fax style gateway (not fax to e-mail since that would involve inbound faxes) That covers a few requirements, depending what you expect to be in the e-mails - send the whole e-mail as a FAX; extract a PDF, Word document, etc. from an e-mail, and turn that into a FAX; and so on. > 3) The reason I asked about e-mail to PDF is the initial comments from my client requested the ability to send PDFs and WORD documents (I guess from attachments to the original e-mail), I understand the format that gets faxed should be TIFF so I saw on the freeswitch wiki email2pdf mentioned. Then ImageMagick can help get a PDF to TIFF. If the incoming e-mails are limited to ones containing PDFs and doc files to be extracted and turned into FAXes things you seem to have a fairly well defined requirement. OpenOffice can be used to turn the doc files into FAXable images, but I am not clear how well the newer docx files are handled. Ghostscript can be used to turn PDFs into TIFF files.
Avoid ImageMagick for this kind of work. It uses Ghostscript to do the hard work, but it doesn't get the best from it. If you use Ghostscript directly you get better control, and you can achieve good results. > Can I ask some more questions: > > Q1) Based on your experience what would be the average time (in seconds) to send a single fax page (TIFF file) via Freeswitch& Sangoma TDM? You can quote a TIFF file size to make it more accurate. From there I should be able to do the math to calculate my Client's requirements better. The time per page depends a lot on its complexity. I use a torture test file with images that take half an hour to send. Typical office work is probably 20s per page at 14400bps. > Q2) Running on CentOS and using mod_spandsp/Freeswitch& Sangoma TDM what percentage CPU usage would I expect to see if 30 concurrent faxes are being sent at the same time (ie. All channels of my E1 are faxing)? (The hardware would be a new 1U rack server from a major hardware vendor) The greater part of the CPU load is likely to be what you didn't list there - the processing from e-mail to FAXable TIFF files. A single E1 of FAXing is a really low load these days, though. > Q3) What version of CentOS 5.x would you recommend? Would the latest version 5.6 be fine? 5.6 is fine. > Q4) From memory there used to be different fax quality modes on fax machines (STANDARD, FINE& SUPER FINE or something like that). Is it possible to set the fax send quality from mod_spandsp (also can you provide an example)? If this is the case could you also answer question (Q1) based on the different fax send quality modes. You can't really set the quality in mod_spandsp. The quality follows the TIFF files to be sent. You can, however, select the image quality as you generate the TIFF files in Ghostscript. STANDARD, FINE and SUPERFINE are the right names, although many machines refuse to use SUPERFINE. > Q5) From exisiting deployments of Freeswitch using mod_spandsp (& Sagoma TDM cards (although this is not critical)) what is the largest number of concurrent outbound faxes done on a single box that you know of? I'm not sure of the biggest, but an E1 of FAXing is pretty small volume these days. The biggest number of channels should be in the hundreds. > I appreciate your feedback and experience. It sounds like this will work fine with the mod_spandsp/Freeswitch& Sangoma TDM combination on CentOS. > > I will most likely go for two servers with at least 2 x E1s in each, that way I future proof it a little and add redundancy. Plus my Client can start using Freeswitch for Voice related services also. On my side I can also test faxes going out on the first server and via a cross-over cable I can terminate them on the second server (for testing) - much nicer. > > Thanks again, > > Andrew Two servers with one E1 in each sounds like more than enough to meet your needs, unless your 30k pages per day occur over a fairly short working hours, and the customer demands rapid delivery. Then you might need more channels to deal with rush hour.
Steve
Steve
On 05/09/2011 08:18 AM, Steve Underwood wrote:
On 05/09/2011 01:16 AM, Juan Antonio Ibañez Santorum wrote:
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? The open source options are:
Asterisk + spandsp Asterisk + Hylafax + iaxmodem + spandsp Freeswitch
These are all tested and proven to give well below 1% failures, even with quite a lot of concurrent FAX channels in use, if things are set up well. They can give you bad failure rates if things are not set up well. I believe that right now you will have less trouble achieving a reliable setup with Freeswitch. Going forward, most of my effort goes into making the Freeswitch option the most thoroughly implemented one.
The main commercial option is:
Asterisk + Digium's commercial FAX
Of course, there are numerous other fully commercial FAXing options which could be used in conjunction with things like Asterisk or Freeswitch
The Digium FAX module is based on the well known Commetrex FAX engine, which is widely deployed, and should be capable of solid results. However, the module is more than just the core FAX engine, and some people do have serious trouble with the module. I have helped moved people off this, and onto Asterisk + spandsp, to improve their reliability. In a couple of those cases people were getting quite a lot of pages cut short when receiving FAXes with T.38, even though a wireshark log showed a perfect exchange, from which I could correctly decode these FAXes. The module was not reporting any errors. In a couple of cases strange machines were sending weird things the Digium FAX didn't cope with very well. I worked with these people to make sure spandsp did handle the weird stuff well, and we ended up with a more usable solution. These people told me that when they complained to Digium they got little help. The best was an offer of a refund. Paying to get some support didn't seem to work out too well for these people, but I guess if the support you are looking for is mostly in getting things configured and working on day one you might get value for money.
All these solutions require reliable signaling and reliable media timing, and many people have setups which cannot achieve that. Most people don't understand how things work, and will claim a solution doesn't function for spurious reasons. For example, a number of people say the spandsp module for Asterisk doesn't work, because they keep getting a 488 response. That response has nothing to do with the FAX engine. It is a negotiation error that occurs outside the FAX engine. If they fixed their configuration the error would go away. However, many just move on, having "proven" to themselves the solution doesn't work.
I forgot one important point. Right now, the only out of the box solution for T.38 gateway is Freeswitch. There are patches in the Digium bugtracker to add T.38 gateway functionality, but its not in the software distribution. They seem to be seriously working on T.38 gateway for a future release of Asterisk. I don't know if there will be a commercial T.38 gateway from Digium. It looks like all their current work is with spandsp. Steve
Steve, I very much appreciate your detailed reply and comments. They have enabled me to feel very confident in proposing FREESWITCH (using mod_spandsp & Sangoma E1 cards) to run a FAX OUT service for my Client. There is only one last question I have. My Client has requested that the initial installation runs on Windows Server 2008. Do you see any issues with the Windows version of FreeSWITCH using mod_spandsp (based on the service design I have already sent through)? I know the Sangoma A10x series of E1 cards do support Windows (via FreeTDM) so I do not see any issue there. Once again thanks so much for all your feedback. Kind Regards, Andrew Keil -----Original Message----- From: freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] On Behalf Of Steve Underwood Sent: Monday, 9 May 2011 10:18 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Major deployment of outbound FAX on latest version of Freeswitch question On 05/09/2011 01:16 AM, Juan Antonio Ibañez Santorum wrote:
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? The open source options are:
Asterisk + spandsp Asterisk + Hylafax + iaxmodem + spandsp Freeswitch These are all tested and proven to give well below 1% failures, even with quite a lot of concurrent FAX channels in use, if things are set up well. They can give you bad failure rates if things are not set up well. I believe that right now you will have less trouble achieving a reliable setup with Freeswitch. Going forward, most of my effort goes into making the Freeswitch option the most thoroughly implemented one. The main commercial option is: Asterisk + Digium's commercial FAX Of course, there are numerous other fully commercial FAXing options which could be used in conjunction with things like Asterisk or Freeswitch The Digium FAX module is based on the well known Commetrex FAX engine, which is widely deployed, and should be capable of solid results. However, the module is more than just the core FAX engine, and some people do have serious trouble with the module. I have helped moved people off this, and onto Asterisk + spandsp, to improve their reliability. In a couple of those cases people were getting quite a lot of pages cut short when receiving FAXes with T.38, even though a wireshark log showed a perfect exchange, from which I could correctly decode these FAXes. The module was not reporting any errors. In a couple of cases strange machines were sending weird things the Digium FAX didn't cope with very well. I worked with these people to make sure spandsp did handle the weird stuff well, and we ended up with a more usable solution. These people told me that when they complained to Digium they got little help. The best was an offer of a refund. Paying to get some support didn't seem to work out too well for these people, but I guess if the support you are looking for is mostly in getting things configured and working on day one you might get value for money. All these solutions require reliable signaling and reliable media timing, and many people have setups which cannot achieve that. Most people don't understand how things work, and will claim a solution doesn't function for spurious reasons. For example, a number of people say the spandsp module for Asterisk doesn't work, because they keep getting a 488 response. That response has nothing to do with the FAX engine. It is a negotiation error that occurs outside the FAX engine. If they fixed their configuration the error would go away. However, many just move on, having "proven" to themselves the solution doesn't work.
2011/5/8 Steve Underwood <steveu@coppice.org <mailto:steveu@coppice.org>>
On 05/07/2011 04:02 AM, Andrew Keil wrote: > Steve, > > Thanks for your response. > > Further clarification on my part: > > 1) 20,000 to 30,000 pages per day to be sent out. So, this is fairly small scale. A single E1 will do fine. > 2) It will be an e-mail to fax style gateway (not fax to e-mail since that would involve inbound faxes) That covers a few requirements, depending what you expect to be in the e-mails - send the whole e-mail as a FAX; extract a PDF, Word document, etc. from an e-mail, and turn that into a FAX; and so on. > 3) The reason I asked about e-mail to PDF is the initial comments from my client requested the ability to send PDFs and WORD documents (I guess from attachments to the original e-mail), I understand the format that gets faxed should be TIFF so I saw on the freeswitch wiki email2pdf mentioned. Then ImageMagick can help get a PDF to TIFF. If the incoming e-mails are limited to ones containing PDFs and doc files to be extracted and turned into FAXes things you seem to have a fairly well defined requirement. OpenOffice can be used to turn the doc files into FAXable images, but I am not clear how well the newer docx files are handled. Ghostscript can be used to turn PDFs into TIFF files.
Avoid ImageMagick for this kind of work. It uses Ghostscript to do the hard work, but it doesn't get the best from it. If you use Ghostscript directly you get better control, and you can achieve good results. > Can I ask some more questions: > > Q1) Based on your experience what would be the average time (in seconds) to send a single fax page (TIFF file) via Freeswitch& Sangoma TDM? You can quote a TIFF file size to make it more accurate. From there I should be able to do the math to calculate my Client's requirements better. The time per page depends a lot on its complexity. I use a torture test file with images that take half an hour to send. Typical office work is probably 20s per page at 14400bps. > Q2) Running on CentOS and using mod_spandsp/Freeswitch& Sangoma TDM what percentage CPU usage would I expect to see if 30 concurrent faxes are being sent at the same time (ie. All channels of my E1 are faxing)? (The hardware would be a new 1U rack server from a major hardware vendor) The greater part of the CPU load is likely to be what you didn't list there - the processing from e-mail to FAXable TIFF files. A single E1 of FAXing is a really low load these days, though. > Q3) What version of CentOS 5.x would you recommend? Would the latest version 5.6 be fine? 5.6 is fine. > Q4) From memory there used to be different fax quality modes on fax machines (STANDARD, FINE& SUPER FINE or something like that). Is it possible to set the fax send quality from mod_spandsp (also can you provide an example)? If this is the case could you also answer question (Q1) based on the different fax send quality modes. You can't really set the quality in mod_spandsp. The quality follows the TIFF files to be sent. You can, however, select the image quality as you generate the TIFF files in Ghostscript. STANDARD, FINE and SUPERFINE are the right names, although many machines refuse to use SUPERFINE. > Q5) From exisiting deployments of Freeswitch using mod_spandsp (& Sagoma TDM cards (although this is not critical)) what is the largest number of concurrent outbound faxes done on a single box that you know of? I'm not sure of the biggest, but an E1 of FAXing is pretty small volume these days. The biggest number of channels should be in the hundreds. > I appreciate your feedback and experience. It sounds like this will work fine with the mod_spandsp/Freeswitch& Sangoma TDM combination on CentOS. > > I will most likely go for two servers with at least 2 x E1s in each, that way I future proof it a little and add redundancy. Plus my Client can start using Freeswitch for Voice related services also. On my side I can also test faxes going out on the first server and via a cross-over cable I can terminate them on the second server (for testing) - much nicer. > > Thanks again, > > Andrew Two servers with one E1 in each sounds like more than enough to meet your needs, unless your 30k pages per day occur over a fairly short working hours, and the customer demands rapid delivery. Then you might need more channels to deal with rush hour.
Steve
Steve _______________________________________________ FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users http://www.freeswitch.org __________ Information from ESET NOD32 Antivirus, version of virus signature database 6105 (20110508) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Hi Andrew, Probably the only thing I can say would be that the Windows port of SpanDsp does not receive the same amount of testing as the Linux build so keep that in mind but there should be no particular reason not to expect the same performance(as far as I know) as other builds. Please update the list here with any results that you experience. Thanks Jeff -- View this message in context: http://freeswitch-users.2379917.n2.nabble.com/Major-deployment-of-outbound-F... Sent from the freeswitch-users mailing list archive at Nabble.com.
Thank you very much for your answer Steve. Would be FS + mod_spandsp good both for incoming and outgoing faxeds? What could be achieved to avoid media timing issues you told? Regards 2011/5/9 Steve Underwood <steveu@coppice.org>
On 05/09/2011 01:16 AM, Juan Antonio Ibañez Santorum wrote:
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? The open source options are:
Asterisk + spandsp Asterisk + Hylafax + iaxmodem + spandsp Freeswitch
These are all tested and proven to give well below 1% failures, even with quite a lot of concurrent FAX channels in use, if things are set up well. They can give you bad failure rates if things are not set up well. I believe that right now you will have less trouble achieving a reliable setup with Freeswitch. Going forward, most of my effort goes into making the Freeswitch option the most thoroughly implemented one.
The main commercial option is:
Asterisk + Digium's commercial FAX
Of course, there are numerous other fully commercial FAXing options which could be used in conjunction with things like Asterisk or Freeswitch
The Digium FAX module is based on the well known Commetrex FAX engine, which is widely deployed, and should be capable of solid results. However, the module is more than just the core FAX engine, and some people do have serious trouble with the module. I have helped moved people off this, and onto Asterisk + spandsp, to improve their reliability. In a couple of those cases people were getting quite a lot of pages cut short when receiving FAXes with T.38, even though a wireshark log showed a perfect exchange, from which I could correctly decode these FAXes. The module was not reporting any errors. In a couple of cases strange machines were sending weird things the Digium FAX didn't cope with very well. I worked with these people to make sure spandsp did handle the weird stuff well, and we ended up with a more usable solution. These people told me that when they complained to Digium they got little help. The best was an offer of a refund. Paying to get some support didn't seem to work out too well for these people, but I guess if the support you are looking for is mostly in getting things configured and working on day one you might get value for money.
All these solutions require reliable signaling and reliable media timing, and many people have setups which cannot achieve that. Most people don't understand how things work, and will claim a solution doesn't function for spurious reasons. For example, a number of people say the spandsp module for Asterisk doesn't work, because they keep getting a 488 response. That response has nothing to do with the FAX engine. It is a negotiation error that occurs outside the FAX engine. If they fixed their configuration the error would go away. However, many just move on, having "proven" to themselves the solution doesn't work.
Juan, I suppose a decent server with a hw clock running at 1000Hz and a recommended OS (that would be CentOS). Also, if you do T38 to send the faxes to an external GW, the smallest possible jitter between your FreeSWITCH and the gateway. Also, if you do T38 for inbound faxes, check that the gateway supports T38 redundancy. David Ponzone Direction Technique email: david.ponzone@ipeva.fr tel: 01 74 03 18 97 gsm: 06 66 98 76 34 Service Client IPeva tel: 0811 46 26 26 www.ipeva.fr - www.ipeva-studio.com Ce message et toutes les pièces jointes sont confidentiels et établis à l'intention exclusive de ses destinataires. Toute utilisation ou diffusion non autorisée est interdite. Tout message électronique est susceptible d'altération. IPeva décline toute responsabilité au titre de ce message s'il a été altéré, déformé ou falsifié. Si vous n'êtes pas destinataire de ce message, merci de le détruire immédiatement et d'avertir l'expéditeur. Le 09/05/2011 à 09:23, Juan Antonio Ibañez Santorum a écrit :
Thank you very much for your answer Steve.
Would be FS + mod_spandsp good both for incoming and outgoing faxeds?
What could be achieved to avoid media timing issues you told?
Regards
2011/5/9 Steve Underwood <steveu@coppice.org> On 05/09/2011 01:16 AM, Juan Antonio Ibañez Santorum wrote:
How much reliable FS + mod_spandsp is compared to other solutions (open source or not)? The open source options are:
Asterisk + spandsp Asterisk + Hylafax + iaxmodem + spandsp Freeswitch
These are all tested and proven to give well below 1% failures, even with quite a lot of concurrent FAX channels in use, if things are set up well. They can give you bad failure rates if things are not set up well. I believe that right now you will have less trouble achieving a reliable setup with Freeswitch. Going forward, most of my effort goes into making the Freeswitch option the most thoroughly implemented one.
The main commercial option is:
Asterisk + Digium's commercial FAX
Of course, there are numerous other fully commercial FAXing options which could be used in conjunction with things like Asterisk or Freeswitch
The Digium FAX module is based on the well known Commetrex FAX engine, which is widely deployed, and should be capable of solid results. However, the module is more than just the core FAX engine, and some people do have serious trouble with the module. I have helped moved people off this, and onto Asterisk + spandsp, to improve their reliability. In a couple of those cases people were getting quite a lot of pages cut short when receiving FAXes with T.38, even though a wireshark log showed a perfect exchange, from which I could correctly decode these FAXes. The module was not reporting any errors. In a couple of cases strange machines were sending weird things the Digium FAX didn't cope with very well. I worked with these people to make sure spandsp did handle the weird stuff well, and we ended up with a more usable solution. These people told me that when they complained to Digium they got little help. The best was an offer of a refund. Paying to get some support didn't seem to work out too well for these people, but I guess if the support you are looking for is mostly in getting things configured and working on day one you might get value for money.
All these solutions require reliable signaling and reliable media timing, and many people have setups which cannot achieve that. Most people don't understand how things work, and will claim a solution doesn't function for spurious reasons. For example, a number of people say the spandsp module for Asterisk doesn't work, because they keep getting a 488 response. That response has nothing to do with the FAX engine. It is a negotiation error that occurs outside the FAX engine. If they fixed their configuration the error would go away. However, many just move on, having "proven" to themselves the solution doesn't work.
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participants (6)
-
Andrew Keil
-
David Ponzone
-
Jeff Lenk
-
Juan Antonio Ibañez Santorum
-
Meftah Tayeb
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Steve Underwood