Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
On 01/08/2013, at 2:20 PM, Zoltán Fekete bl...@gyoz.info wrote: 2013/8/1 Joshua Colp jc...@digium.com Larry Moore wrote: On 31/07/2013 8:08 PM, Joshua Colp wrote: Zoltán Fekete wrote: Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/anonymous/6120148 (line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Based on the SDP in your gist the remote implementation has given no attributes with the T.38 stream which makes it pretty broken (T38FaxRateManagement is mandatory) and fun. The two hard parts really would be 1. Modifying Asterisk in a sane fashion to cope and 2. Determining the exact settings to make the implementation happy. Defaults as defined in the spec are fine and good, but my experience has taught me to throw those out the window when it comes to actual implementations. It would seem that having a configurable option would be an idea for this scenario. That implies it would solve the problem, which my gut and experience tells me... it wouldn't. I think the T.38 implementation is just cobbled together and without knowing exactly how it behaves getting it to work would likely be a nightmare (trust me, I've spent time in those deep dark reaches). Throwing assumptions and defaults at it to try to make it work is of course an option. My testing with Asterisk 1.8 and T.38, I obserevd that setting FAXOPT(minrate) or FAXOPT(maxrate)had no effect, I concluded that when Astrerisk is receiving it uses hard coded values - is this a sane thing to do?! When Asterisk is receiving the stack implementation offers what it wants, with the ability to override. So Asterisk doesn't hard code those values, the stack provides them. What is hard coded is the default values if none are received. I would even say it's a bug that the negotiation doesn't fail, since the remote side isn't providing a mandatory attribute. -- Joshua Colp Digium, Inc. | Senior Software Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com www.asterisk.org -- _ Yes you're right! As I know FAXOPT() value affect only when asterisk woks as gateway. We need passtrouh because my endpoints and also my provider supports T38. https://wiki.asterisk.org/wiki/display/AST/T.38+Fax+Gateway Using T.38 Gateway mode T.38 Gateway mode should be used when one leg of a call is not capable of T.38 mode. In the event that both legs are capable and Gateway mode is configured, then the Gateway will step out of the way, allowing transparent T.38 passthrough. The main problem is that I can't use G711 for the entire fax session because the endpoints has 20-30ms response time. When I try to use my Asterisk as FAXOPT gateway (endpoint leg T38 and provider leg G711) can I force somehow to not accept the T38 re-INVITEs from the provider? They have ~1ms response time, so G711 on that leg would be fine but they also detect fax CED tones and sends the re-INVITEs. Have you tried setting in your sip.conf for your provider t38pt_udptl=no whilst having the gateway option enabled? Sorry I cant test this myself. Cheers, Larry.-- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
2013/8/1 Joshua Colp jc...@digium.com Larry Moore wrote: On 31/07/2013 8:08 PM, Joshua Colp wrote: Zoltán Fekete wrote: Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/**anonymous/6120148https://gist.github.com/anonymous/6120148(line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Based on the SDP in your gist the remote implementation has given no attributes with the T.38 stream which makes it pretty broken (T38FaxRateManagement is mandatory) and fun. The two hard parts really would be 1. Modifying Asterisk in a sane fashion to cope and 2. Determining the exact settings to make the implementation happy. Defaults as defined in the spec are fine and good, but my experience has taught me to throw those out the window when it comes to actual implementations. It would seem that having a configurable option would be an idea for this scenario. That implies it would solve the problem, which my gut and experience tells me... it wouldn't. I think the T.38 implementation is just cobbled together and without knowing exactly how it behaves getting it to work would likely be a nightmare (trust me, I've spent time in those deep dark reaches). Throwing assumptions and defaults at it to try to make it work is of course an option. My testing with Asterisk 1.8 and T.38, I obserevd that setting FAXOPT(minrate) or FAXOPT(maxrate)had no effect, I concluded that when Astrerisk is receiving it uses hard coded values - is this a sane thing to do?! When Asterisk is receiving the stack implementation offers what it wants, with the ability to override. So Asterisk doesn't hard code those values, the stack provides them. What is hard coded is the default values if none are received. I would even say it's a bug that the negotiation doesn't fail, since the remote side isn't providing a mandatory attribute. -- Joshua Colp Digium, Inc. | Senior Software Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com www.asterisk.org -- __**__**_ Yes you're right! As I know FAXOPT() value affect only when asterisk woks as gateway. We need passtrouh because my endpoints and also my provider supports T38. https://wiki.asterisk.org/wiki/display/AST/T.38+Fax+Gateway Using T.38 Gateway mode T.38 Gateway mode should be used when one leg of a call is not capable of T.38 mode. In the event that both legs are capable and Gateway mode is configured, then the Gateway will step out of the way, allowing *transparent T.38 passthrough*. The main problem is that I can't use G711 for the entire fax session because the endpoints has 20-30ms response time. When I try to use my Asterisk as FAXOPT gateway (endpoint leg T38 and provider leg G711) can I force somehow to not accept the T38 re-INVITEs from the provider? They have ~1ms response time, so G711 on that leg would be fine but they also detect fax CED tones and sends the re-INVITEs. Regards, Blaxy -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/anonymous/6120148 (line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Regards, Blaxy 2013/7/23 Larry Moore lmo...@omninet.net.au On 23/07/2013 6:18 AM, Kevin Larsen wrote: The a=T38MaxBitRate issue you refer to was one that was actually discovered at my company and submitted by a colleague. It was fixed in 11.3.0 and 1.8.21.0. However, I think that it wouldn't help based on the description below being that the parameter was missing altogether. I think if that parameter is missing, then the code would in fact default to 2400 as a safe value. The Case Insensitive checking of the T.38 attributes was introduced in these versions. Looking at the ITU-T T.38 Implementors' Guide (11 May 2012)in Table H.2, if the T38MaxBitRate attribute is omitted they suggest using the default value, they indicate a default value of 14400. Larry. -- __**__**_ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/**mailman/listinfo/asterisk-**usershttp://lists.digium.com/mailman/listinfo/asterisk-users -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
Zoltán Fekete wrote: Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/anonymous/6120148 (line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Based on the SDP in your gist the remote implementation has given no attributes with the T.38 stream which makes it pretty broken (T38FaxRateManagement is mandatory) and fun. The two hard parts really would be 1. Modifying Asterisk in a sane fashion to cope and 2. Determining the exact settings to make the implementation happy. Defaults as defined in the spec are fine and good, but my experience has taught me to throw those out the window when it comes to actual implementations. Cheers, -- Joshua Colp Digium, Inc. | Senior Software Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com www.asterisk.org -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
On 31/07/2013 8:08 PM, Joshua Colp wrote: Zoltán Fekete wrote: Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/anonymous/6120148 (line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Based on the SDP in your gist the remote implementation has given no attributes with the T.38 stream which makes it pretty broken (T38FaxRateManagement is mandatory) and fun. The two hard parts really would be 1. Modifying Asterisk in a sane fashion to cope and 2. Determining the exact settings to make the implementation happy. Defaults as defined in the spec are fine and good, but my experience has taught me to throw those out the window when it comes to actual implementations. It would seem that having a configurable option would be an idea for this scenario. My testing with Asterisk 1.8 and T.38, I obserevd that setting FAXOPT(minrate) or FAXOPT(maxrate)had no effect, I concluded that when Astrerisk is receiving it uses hard coded values - is this a sane thing to do?! If Asterisk T.38 reception could be configured to use the values defined in FAXOPT(minrate) or FAXOPT(maxrate)this would be a good starting point for situations like this one. Cheers, Larry. -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
Larry Moore wrote: On 31/07/2013 8:08 PM, Joshua Colp wrote: Zoltán Fekete wrote: Thank You Larry! I have discussed with my provider. They are not able to insert the T38MaxBitRate value into the sip answer. :( https://gist.github.com/anonymous/6120148 (line 559) That means we are not able to passtrough T38 Faxes with any asterisk version at all? What do you mean? Am I able to modify and compile the source? Is it compicated? (I'm not a developer) Based on the SDP in your gist the remote implementation has given no attributes with the T.38 stream which makes it pretty broken (T38FaxRateManagement is mandatory) and fun. The two hard parts really would be 1. Modifying Asterisk in a sane fashion to cope and 2. Determining the exact settings to make the implementation happy. Defaults as defined in the spec are fine and good, but my experience has taught me to throw those out the window when it comes to actual implementations. It would seem that having a configurable option would be an idea for this scenario. That implies it would solve the problem, which my gut and experience tells me... it wouldn't. I think the T.38 implementation is just cobbled together and without knowing exactly how it behaves getting it to work would likely be a nightmare (trust me, I've spent time in those deep dark reaches). Throwing assumptions and defaults at it to try to make it work is of course an option. My testing with Asterisk 1.8 and T.38, I obserevd that setting FAXOPT(minrate) or FAXOPT(maxrate)had no effect, I concluded that when Astrerisk is receiving it uses hard coded values - is this a sane thing to do?! When Asterisk is receiving the stack implementation offers what it wants, with the ability to override. So Asterisk doesn't hard code those values, the stack provides them. What is hard coded is the default values if none are received. I would even say it's a bug that the negotiation doesn't fail, since the remote side isn't providing a mandatory attribute. -- Joshua Colp Digium, Inc. | Senior Software Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com www.asterisk.org -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
On 22/07/2013 5:40 AM, Zoltán Fekete wrote: Hi! I have exactly the same problem on asterisk 1.8.22.0 and also on separate 11.2.1 when sending fax to PSTN. Tryed with spa-3102, spa-2102, Patton Smartnode 4634, and Zoiper softphone. SpanDsp also works without any problem on my box. As I remember it was a bug in 1.8.1.x that the a=T38MaxBitRate paramater was sent as maxBitRate. Without capital M. Are you closer to the solution? I have tryed almost anything and I don't understand why sends the T38MaxBitRate:2400 parameter. Could it be because the remote endpoint does not supply the T38MaxBitRate attribute in its reply which then leads to Asterisk applying the Minimum Rate to your ATA!? I am referring to the information around lines 403 404 of https://gist.github.com/anonymous/5701207. Do you know what the Fax Rate was for the connection in https://gist.github.com/anonymous/5701150. What happens if you insert in your dialplan something like Set(FAXOPT(minrate)=4800) Cheers, Larry. -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
The a=T38MaxBitRate issue you refer to was one that was actually discovered at my company and submitted by a colleague. It was fixed in 11.3.0 and 1.8.21.0. However, I think that it wouldn't help based on the description below being that the parameter was missing altogether. I think if that parameter is missing, then the code would in fact default to 2400 as a safe value. Kevin Larsen - Systems Analyst From: Zoltán Fekete bl...@gyoz.info To: asterisk-users@lists.digium.com, Date: 07/21/2013 04:40 PM Subject:[asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work Sent by:asterisk-users-boun...@lists.digium.com Hi! I have exactly the same problem on asterisk 1.8.22.0 and also on separate 11.2.1 when sending fax to PSTN. Tryed with spa-3102, spa-2102, Patton Smartnode 4634, and Zoiper softphone. SpanDsp also works without any problem on my box. As I remember it was a bug in 1.8.1.x that the a=T38MaxBitRate paramater was sent as maxBitRate. Without capital M. Are you closer to the solution? I have tryed almost anything and I don't understand why sends the T38MaxBitRate:2400 parameter. regards, Blaxy On 06/03/2013 05:03 PM, Larry Moore wrote: Have you checked the installed version of firmware against the latest available from Cisco? Oh! I didn't guess to check. The firmware was not fresh, but upgrading doesn't help. Looking at your SIP information when your ITSP initiated a T.38 session it did not indicate a maxmimum bitrate, it would appear your spa112 attempted to negotiate a connection at 2400bps. Whether there is a way to force my provider to indicate maximum bitrate? Do you have a sip debug session when you sent a fax from your Asterisk box to the PSTN, it would be interesting to see if it sends it as a t.38 or reverts to G711 audio. I have collect a set of debugs (with fresh SPA112 firmware) and actual config files: == spa112 — cmd ReceiveFax https://gist.github.com/anonymous/5701032 == cmd SendFax — PSTN https://gist.github.com/anonymous/5701150 == spa112 — PSTN https://gist.github.com/anonymous/5701207 == sip.conf https://gist.github.com/anonymous/5701231 == udptl.conf https://gist.github.com/anonymous/5701247 __ This email has been scanned by the Symantec Email Security.cloud service. For more information please visit http://www.symanteccloud.com __-- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
On 23/07/2013 6:18 AM, Kevin Larsen wrote: The a=T38MaxBitRate issue you refer to was one that was actually discovered at my company and submitted by a colleague. It was fixed in 11.3.0 and 1.8.21.0. However, I think that it wouldn't help based on the description below being that the parameter was missing altogether. I think if that parameter is missing, then the code would in fact default to 2400 as a safe value. The Case Insensitive checking of the T.38 attributes was introduced in these versions. Looking at the ITU-T T.38 Implementors' Guide (11 May 2012)in Table H.2, if the T38MaxBitRate attribute is omitted they suggest using the default value, they indicate a default value of 14400. Larry. -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
Re: [asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
On 22/07/2013 10:19 PM, Larry Moore wrote: On 22/07/2013 5:40 AM, Zoltán Fekete wrote: Hi! I have exactly the same problem on asterisk 1.8.22.0 and also on separate 11.2.1 when sending fax to PSTN. Tryed with spa-3102, spa-2102, Patton Smartnode 4634, and Zoiper softphone. SpanDsp also works without any problem on my box. As I remember it was a bug in 1.8.1.x that the a=T38MaxBitRate paramater was sent as maxBitRate. Without capital M. Are you closer to the solution? I have tryed almost anything and I don't understand why sends the T38MaxBitRate:2400 parameter. Could it be because the remote endpoint does not supply the T38MaxBitRate attribute in its reply which then leads to Asterisk applying the Minimum Rate to your ATA!? I am referring to the information around lines 403 404 of https://gist.github.com/anonymous/5701207. Do you know what the Fax Rate was for the connection in https://gist.github.com/anonymous/5701150. What happens if you insert in your dialplan something like Set(FAXOPT(minrate)=4800) Another suggestion might be to set the variable in the peer configuration like; setvar=FAXOPT(minrate)=4800 Larry. -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
[asterisk-users] Fwd: Re: Asterisk T.38 Pass-Through doesn't work
Hi! I have exactly the same problem on asterisk 1.8.22.0 and also on separate 11.2.1 when sending fax to PSTN. Tryed with spa-3102, spa-2102, Patton Smartnode 4634, and Zoiper softphone. SpanDsp also works without any problem on my box. As I remember it was a bug in 1.8.1.x that the a=T38MaxBitRate paramater was sent as maxBitRate. Without capital M. Are you closer to the solution? I have tryed almost anything and I don't understand why sends the T38MaxBitRate:2400 parameter. regards, Blaxy On 06/03/2013 05:03 PM, Larry Moore wrote: Have you checked the installed version of firmware against the latest available from Cisco? Oh! I didn't guess to check. The firmware was not fresh, but upgrading doesn't help. Looking at your SIP information when your ITSP initiated a T.38 session it did not indicate a maxmimum bitrate, it would appear your spa112 attempted to negotiate a connection at 2400bps. Whether there is a way to force my provider to indicate maximum bitrate? Do you have a sip debug session when you sent a fax from your Asterisk box to the PSTN, it would be interesting to see if it sends it as a t.38 or reverts to G711 audio. I have collect a set of debugs (with fresh SPA112 firmware) and actual config files: == spa112 — cmd ReceiveFax https://gist.github.com/anonymous/5701032 == cmd SendFax — PSTN https://gist.github.com/anonymous/5701150 == spa112 — PSTN https://gist.github.com/anonymous/5701207 == sip.conf https://gist.github.com/anonymous/5701231 == udptl.conf https://gist.github.com/anonymous/5701247 -- _ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
