Fax Transmit Rate - force to 9600?
Hi all, We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan: action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of the fax_v17_disabled=true setting). However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate. I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities. Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability. Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate. Any advice on this or are we missing something with regards to locking in the lower speed? cheers, A
Hi, From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600. Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr .
On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com> wrote:
Hi all,
We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan:
action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup
The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting).
However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate.
I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities.
Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely
My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability.
Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate.
Any advice on this or are we missing something with regards to locking in the lower speed?
cheers, A
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Thanks Vallimamod, that gives me some additional info we weren't aware of (re: preamble and t38 max bitrate). I noticed you mentioned disabling v17; which would allow the bitrate to increase to 14400, which is where we're seeing the problem. We want to force/limit the max bitrate under all circumstances (t38 or t30 over g711) to 9600, which we know works. Some additional info; Doing some further digging; the problem doesn't appear to specifically lie with t38; from what we can see some fax calls come in via t30 over g711 which also fail with a bit rate of 14400. Given the preamble info you mentioned, could it be we're sending the sending fax our capabilities (i.e. max bitrate = 9600) and it's ignoring this and sends it across at 14400? I would assume that most, if not all faxes have the capability to send at 9600 if requested? Given our issue relates to incoming (i.e we're the receiving end), is there anything else we can do within FS to force the lower bit rate? cheers, A ________________________________ From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org> on behalf of Vallimamod Abdullah <vma@vallimamod.org> Sent: Thursday, 1 March 2018 4:34 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600? Hi,
From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600.
Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr<mailto:vma@sipsolutions.fr> . On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com<mailto:asims1979@hotmail.com>> wrote: Hi all, We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan: action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting). However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate. I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities. Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability. Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate. Any advice on this or are we missing something with regards to locking in the lower speed? cheers, A _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org<mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com<http://www.freeswitchsolutions.com/> Official FreeSWITCH Sites http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. http://confluence.freeswitch.org<http://confluence.freeswitch.org/> http://www.cluecon.com<http://www.cluecon.com/> [https://cluecon.com/theme/img/cluecon/hook1.jpg]<http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference<http://www.cluecon.com/> www.cluecon.com ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry. FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org<mailto:FreeSWITCH-users@lists.freeswitch.org> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users FreeSWITCH-users Info Page<http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> lists.freeswitch.org To see the collection of prior postings to the list, visit the FreeSWITCH-users Archives. Using FreeSWITCH-users: To post a message to all the list ... UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users FreeSWITCH-users list: member options login page<http://lists.freeswitch.org/mailman/options/freeswitch-users> lists.freeswitch.org In order to change your membership option, you must first log in by giving your email address and membership password in the section below. http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
its not uncommon for 14400 faxes to fail over g711. should have better luck with t38.
On Feb 28, 2018, at 6:39 PM, Andrew <asims1979@hotmail.com> wrote:
Thanks Vallimamod, that gives me some additional info we weren't aware of (re: preamble and t38 max bitrate).
I noticed you mentioned disabling v17; which would allow the bitrate to increase to 14400, which is where we're seeing the problem. We want to force/limit the max bitrate under all circumstances (t38 or t30 over g711) to 9600, which we know works.
Some additional info;
Doing some further digging; the problem doesn't appear to specifically lie with t38; from what we can see some fax calls come in via t30 over g711 which also fail with a bit rate of 14400.
Given the preamble info you mentioned, could it be we're sending the sending fax our capabilities (i.e. max bitrate = 9600) and it's ignoring this and sends it across at 14400? I would assume that most, if not all faxes have the capability to send at 9600 if requested?
Given our issue relates to incoming (i.e we're the receiving end), is there anything else we can do within FS to force the lower bit rate?
cheers, A
From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org <mailto:freeswitch-users-bounces@lists.freeswitch.org>> on behalf of Vallimamod Abdullah <vma@vallimamod.org <mailto:vma@vallimamod.org>> Sent: Thursday, 1 March 2018 4:34 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600?
Hi,
From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600.
Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr <mailto:vma@sipsolutions.fr> .
On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com <mailto:asims1979@hotmail.com>> wrote:
Hi all,
We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan:
action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup
The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting).
However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate.
I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities.
Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely
My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability.
Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate.
Any advice on this or are we missing something with regards to locking in the lower speed?
cheers, A
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org <mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com <http://www.freeswitchsolutions.com/>
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Thanks Michael, that's what we observed with t38 too, however here's a t38 curve ball I've come across; I looked at a few recent failed incoming faxes that used t38. As an example, all showed the following characteristics. The SDP info suggests MaxBitRate should be 9600 via t38, which is in-line with Vallimamod's comments earlier: t38 a=T38FaxVersion:0 a=T38MaxBitRate:9600 a=T38FaxFillBitRemoval:0 a=T 38FaxTranscodingMMR:0 a=T38FaxTranscodingJBIG:0 a=T38FaxRateManagement:tr ansferredTCF a=T38FaxMaxBuffer:200 a=T38FaxMaxDatagram:400 a=T38FaxUdpEC :t38UDPRedundancy However, the fax_transfer_rate variable shows 14400 as the speed. I'm just not sure how that could be possible if t38 sets the max rate at 9600? ________________________________ From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org> on behalf of Michael Jerris <mike@jerris.com> Sent: Thursday, 1 March 2018 10:53 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600? its not uncommon for 14400 faxes to fail over g711. should have better luck with t38. On Feb 28, 2018, at 6:39 PM, Andrew <asims1979@hotmail.com<mailto:asims1979@hotmail.com>> wrote: Thanks Vallimamod, that gives me some additional info we weren't aware of (re: preamble and t38 max bitrate). I noticed you mentioned disabling v17; which would allow the bitrate to increase to 14400, which is where we're seeing the problem. We want to force/limit the max bitrate under all circumstances (t38 or t30 over g711) to 9600, which we know works. Some additional info; Doing some further digging; the problem doesn't appear to specifically lie with t38; from what we can see some fax calls come in via t30 over g711 which also fail with a bit rate of 14400. Given the preamble info you mentioned, could it be we're sending the sending fax our capabilities (i.e. max bitrate = 9600) and it's ignoring this and sends it across at 14400? I would assume that most, if not all faxes have the capability to send at 9600 if requested? Given our issue relates to incoming (i.e we're the receiving end), is there anything else we can do within FS to force the lower bit rate? cheers, A ________________________________ From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org<mailto:freeswitch-users-bounces@lists.freeswitch.org>> on behalf of Vallimamod Abdullah <vma@vallimamod.org<mailto:vma@vallimamod.org>> Sent: Thursday, 1 March 2018 4:34 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600? Hi,
From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600.
Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr<mailto:vma@sipsolutions.fr> . On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com<mailto:asims1979@hotmail.com>> wrote: Hi all, We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan: action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting). However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate. I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities. Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability. Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate. Any advice on this or are we missing something with regards to locking in the lower speed? cheers, A _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org<mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com<http://www.freeswitchsolutions.com/> Official FreeSWITCH Sites http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. http://confluence.freeswitch.org<http://confluence.freeswitch.org/> http://www.cluecon.com<http://www.cluecon.com/> [https://cluecon.com/theme/img/cluecon/hook1.jpg]<http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference<http://www.cluecon.com/> www.cluecon.com<http://www.cluecon.com/> [https://cluecon.com/theme/img/cluecon/hook1.jpg]<http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference<http://www.cluecon.com/> www.cluecon.com ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry. ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry. 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In order to change your membership option, you must first log in by giving your email address and membership password in the section below. http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org<mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com<http://www.freeswitchsolutions.com/> Official FreeSWITCH Sites http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. http://confluence.freeswitch.org<http://confluence.freeswitch.org/> http://www.cluecon.com<http://www.cluecon.com/> [https://cluecon.com/theme/img/cluecon/hook1.jpg]<http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference<http://www.cluecon.com/> www.cluecon.com ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry. 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Hi, You can try fax_transfer_rate var https://freeswitch.org/confluence/display/FREESWITCH/Variables or configure spandsp https://freeswitch.org/confluence/display/FREESWITCH/mod_spandsp On Thu, Mar 1, 2018 at 8:39 AM, Andrew <asims1979@hotmail.com> wrote:
Thanks Vallimamod, that gives me some additional info we weren't aware of (re: preamble and t38 max bitrate).
I noticed you mentioned disabling v17; which would allow the bitrate to increase to 14400, which is where we're seeing the problem. We want to force/limit the max bitrate under all circumstances (t38 or t30 over g711) to 9600, which we know works.
Some additional info;
Doing some further digging; the problem doesn't appear to specifically lie with t38; from what we can see some fax calls come in via t30 over g711 which also fail with a bit rate of 14400.
Given the preamble info you mentioned, could it be we're sending the sending fax our capabilities (i.e. max bitrate = 9600) and it's ignoring this and sends it across at 14400? I would assume that most, if not all faxes have the capability to send at 9600 if requested?
Given our issue relates to incoming (i.e we're the receiving end), is there anything else we can do within FS to force the lower bit rate?
cheers, A
------------------------------ *From:* FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org> on behalf of Vallimamod Abdullah <vma@vallimamod.org> *Sent:* Thursday, 1 March 2018 4:34 AM *To:* FreeSWITCH Users Help *Subject:* Re: [Freeswitch-users] Fax Transmit Rate - force to 9600?
Hi,
From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600.
Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr .
On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com> wrote:
Hi all,
We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan:
action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif
application hangup
The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting).
However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate.
I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities.
Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are:
- Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely
My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability.
Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate.
Any advice on this or are we missing something with regards to locking in the lower speed?
cheers, A
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
Official FreeSWITCH Sites http://www.freeswitch.org <http://www.freeswitch.org/> FreeSWITCH <http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
http://confluence.freeswitch.org http://www.cluecon.com <http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference <http://www.cluecon.com/> www.cluecon.com ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry.
FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org http://lists.freeswitch.org/mailman/listinfo/freeswitch-users FreeSWITCH-users Info Page <http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> lists.freeswitch.org To see the collection of prior postings to the list, visit the FreeSWITCH-users Archives. Using FreeSWITCH-users: To post a message to all the list ...
UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users FreeSWITCH-users list: member options login page <http://lists.freeswitch.org/mailman/options/freeswitch-users> lists.freeswitch.org In order to change your membership option, you must first log in by giving your email address and membership password in the section below.
http://www.freeswitch.org <http://www.freeswitch.org/> FreeSWITCH <http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
_________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org http://www.freeswitchsolutions.com
Official FreeSWITCH Sites http://www.freeswitch.org http://confluence.freeswitch.org http://www.cluecon.com
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-- Alex Sibyakin | Support Engineer FreeSWITCH Solutions | 17345 Civic Drive #2531 Brookfield, WI 53045 <https://maps.google.com/?q=17345+Civic+Drive+%232531+Brookfield,+WI+53045&entry=gmail&source=g> Email: alex@freeswitch.com Website: https://www.FreeSWITCH.com <https://www.freeswitch.com/> Need commercial support? Contact sales@freeswitch.com for details.
Hi Alexy, When setting: fax_transfer_rate=9600 The result is: 2018-03-01 18:31:24.986610 [WARNING] mod_spandsp.c:667 Unknown parameter fax_transfer_rate That was set in the dialplan, not spandsp config - does it make a difference where its set? I didn't see it in the list of settings for mod_spandsp; only as a result variable. cheers, Andrew ________________________________ From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org> on behalf of Alexey Sibyakin <alex@freeswitch.com> Sent: Thursday, 1 March 2018 11:20 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600? Hi, You can try fax_transfer_rate var https://freeswitch.org/confluence/display/FREESWITCH/Variables Variables - FreeSWITCH - Confluence<https://freeswitch.org/confluence/display/FREESWITCH/Variables> freeswitch.org Variable References. You will see references to variables in the dialplan of the form ${variable} as well as $${variable}. $${variable} is evaluated once and becomes ... or configure spandsp https://freeswitch.org/confluence/display/FREESWITCH/mod_spandsp mod_spandsp - FreeSWITCH - Confluence<https://freeswitch.org/confluence/display/FREESWITCH/mod_spandsp> freeswitch.org mod_spandsp is enabled by default in modules.conf and therefore compiled automatically. Its also enabled by default in modules.conf.xml. Ensure that you have libtiff ... On Thu, Mar 1, 2018 at 8:39 AM, Andrew <asims1979@hotmail.com<mailto:asims1979@hotmail.com>> wrote: Thanks Vallimamod, that gives me some additional info we weren't aware of (re: preamble and t38 max bitrate). I noticed you mentioned disabling v17; which would allow the bitrate to increase to 14400, which is where we're seeing the problem. We want to force/limit the max bitrate under all circumstances (t38 or t30 over g711) to 9600, which we know works. Some additional info; Doing some further digging; the problem doesn't appear to specifically lie with t38; from what we can see some fax calls come in via t30 over g711 which also fail with a bit rate of 14400. Given the preamble info you mentioned, could it be we're sending the sending fax our capabilities (i.e. max bitrate = 9600) and it's ignoring this and sends it across at 14400? I would assume that most, if not all faxes have the capability to send at 9600 if requested? Given our issue relates to incoming (i.e we're the receiving end), is there anything else we can do within FS to force the lower bit rate? cheers, A ________________________________ From: FreeSWITCH-users <freeswitch-users-bounces@lists.freeswitch.org<mailto:freeswitch-users-bounces@lists.freeswitch.org>> on behalf of Vallimamod Abdullah <vma@vallimamod.org<mailto:vma@vallimamod.org>> Sent: Thursday, 1 March 2018 4:34 AM To: FreeSWITCH Users Help Subject: Re: [Freeswitch-users] Fax Transmit Rate - force to 9600? Hi,
From the error message, it looks like the remote fax drops the call when it sees no match between capabilities (it's the receiving fax who sends the preamble with its capabilities first.) According to the source code, with v17 disabled, the max bitrate over t38 is 9600, else it's 14400. So I guess you need to enable v17 to communicate with faxes with min bitrates greater than 9600.
Best Regards, -- Vallimamod Abdullah SIP Solutions vma@sipsolutions.fr<mailto:vma@sipsolutions.fr> . On 28 Feb 2018, at 02:32, Andrew <asims1979@hotmail.com<mailto:asims1979@hotmail.com>> wrote: Hi all, We've been trying to get our fax implementation as reliable as possible using FS; we've had some great results with inbound faxes with the following items set in the incoming dial-plan: action application ="answer"/> action application="playback" data="silence_stream://2000"/> action set ignore_early_media=true action set absolute_codec_string='PCMU,PCMA' action set fax_enable_t38=true action set fax_verbose=true action set fax_use_ecm=true action set disable-v17=true action set fax_v17_disabled=true action set fax_disable_v17=true action set fax_enable_t38_request=true application rxfax /tmp/FAX-IN-${uuid}.tif application hangup The one thing that we have identified with this configuration is that 99% of inbound faxes come through fine when the fax transfer rate is negotiated at 9600 bps (as a result of thefax_v17_disabled=true setting). However, we still see quite a few incoming faxes reported as coming in with a fax transfer rate of 14400 bps, which have a 100% fail rate. I understand that the two ends need to negotiate a rate; but how do we force (or only offer) the rate of 9600 or lower? My understanding is that the fax_v17_disabled=true setting should cover that? My first thought was that the remote end was forcing the rate at 14400, regardless of what we were sending back in terms of fax capabilities. Not sure if it helps, but the two error messages we receive when faxes fail due to the 14400 rate are: - Unexpected DCN while waiting for DCS or DIS, and - The call dropped prematurely My thought was, If we could find a way to get all faxes coming in at 9600, we'd be able to improve the reliability. Looking through the wiki and previous list messages, the fax_disable_v17=true setting seems to be the documented approach, but I'm not sure why we're still seeing faxes come in at a higher rate. Any advice on this or are we missing something with regards to locking in the lower speed? cheers, A _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org<mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com<http://www.freeswitchsolutions.com/> Official FreeSWITCH Sites http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org<http://www.freeswitch.org> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. http://confluence.freeswitch.org<http://confluence.freeswitch.org/> http://www.cluecon.com<http://www.cluecon.com/> [https://cluecon.com/theme/img/cluecon/hook1.jpg]<http://www.cluecon.com/> ClueCon Telephony and WebRTC Developer's conference<http://www.cluecon.com/> www.cluecon.com<http://www.cluecon.com> ClueCon is an annual event bringing together all of the open source Telephony and WebRTC developers to collaberate on the latest technology in the communications industry. FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org<mailto:FreeSWITCH-users@lists.freeswitch.org> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users FreeSWITCH-users Info Page<http://lists.freeswitch.org/mailman/listinfo/freeswitch-users> lists.freeswitch.org<http://lists.freeswitch.org> To see the collection of prior postings to the list, visit the FreeSWITCH-users Archives. Using FreeSWITCH-users: To post a message to all the list ... UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users FreeSWITCH-users list: member options login page<http://lists.freeswitch.org/mailman/options/freeswitch-users> lists.freeswitch.org<http://lists.freeswitch.org> In order to change your membership option, you must first log in by giving your email address and membership password in the section below. http://www.freeswitch.org<http://www.freeswitch.org/> [https://freeswitch.org/theme/img/freeswitch-social.png]<http://www.freeswitch.org/> FreeSWITCH<http://www.freeswitch.org/> www.freeswitch.org<http://www.freeswitch.org> FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications. _________________________________________________________________________ Professional FreeSWITCH Consulting Services: consulting@freeswitch.org<mailto:consulting@freeswitch.org> http://www.freeswitchsolutions.com Official FreeSWITCH Sites http://www.freeswitch.org http://confluence.freeswitch.org http://www.cluecon.com FreeSWITCH-users mailing list FreeSWITCH-users@lists.freeswitch.org<mailto: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 -- [https://docs.google.com/uc?export=download&id=1xswZRZyVDo0WQhaemK47pU266yzDR...] Alex Sibyakin | Support Engineer FreeSWITCH Solutions | 17345 Civic Drive #2531 Brookfield, WI 53045<https://maps.google.com/?q=17345+Civic+Drive+%232531+Brookfield,+WI+53045&entry=gmail&source=g> Email: alex@freeswitch.com<mailto:alex@freeswitch.com> Website: https://www.FreeSWITCH.com<https://www.freeswitch.com/> Need commercial support? Contact sales@freeswitch.com<mailto:sales@freeswitch.com> for details.
participants (4)
-
Alexey Sibyakin
-
Andrew
-
Michael Jerris
-
Vallimamod Abdullah