I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38 fax relay.
According to Level-3 they "think" the problem lies in the "Media Description" field of the SDP message I am sending them. The problem is related to the "Media Format" sub-field (value 101) that I am sending, which according to them should be removed.
The SDP "Media Description" field I am sending, looks as follows:
"m=audio 20744 RTP/AVP 0 101"
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk ---> SER ---> Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and prints a blank page.
My questions are as follows:
1) Could the "Media Format" 101 be the problem? If so, how do I remove the 101? This change is probably in Asterisk, as it initiates the call, and not SER, or probably both.
2) If not, should I be looking elsewhere in SER/Asterisk to solve this problem?
regards,
SCM
scm-j@nuntius.com wrote:
I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38 fax relay.
According to Level-3 they “think” the problem lies in the “Media Description” field of the SDP message I am sending them. The problem is related to the “Media Format” sub-field (value 101) that I am sending, which according to them should be removed.
The SDP “Media Description” field I am sending, looks as follows:
“m=audio 20744 RTP/AVP 0 101”
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk -à SER -à Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and prints a blank page.
My questions are as follows:
Could the “Media Format” 101 be the problem? If so, how do Iremove the 101? This change is probably in Asterisk, as it initiates the call, and not SER, or probably both.
I don't think that this will cause problem. If this is really the problem, than the L3 gateway su$%s.
If not, should I be looking elsewhere in SER/Asterisk to solvethis problem?
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
regards, klaus
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
A PSTN fax machine comes in to the Asterisk (via SIP or IAX. tested both ways but neither works), where the caller gets authenticated (via ANI or DTMF) and the destination leg of the call is originated by Asterisk to Level-3 via SER...
-----Original Message----- From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Sent: Thursday, February 17, 2005 9:46 AM To: scm-j@nuntius.com Cc: serusers@lists.iptel.org Subject: Re: [Serusers] Fax problem with SER/Asterisk
scm-j@nuntius.com wrote:
I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38
fax
relay.
According to Level-3 they think the problem lies in the Media Description field of the SDP message I am sending them. The problem
is
related to the Media Format sub-field (value 101) that I am
sending,
which according to them should be removed.
The SDP Media Description field I am sending, looks as follows:
m=audio 20744 RTP/AVP 0 101
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk -à SER -à Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and
prints a blank page.
My questions are as follows:
Could the Media Format 101 be the problem? If so, how do Iremove the 101? This change is probably in Asterisk, as it initiates
the
call, and not SER, or probably both.
I don't think that this will cause problem. If this is really the problem, than the L3 gateway su$%s.
If not, should I be looking elsewhere in SER/Asterisk to
solve
this problem?
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
regards, klaus
.. I should found out by myself that you use asterisk :)
Same stuff... remove rfcxxxx from dtmf configuration in sip.conf
-----Original Message----- From: serusers-bounces@iptel.org [mailto:serusers-bounces@lists.iptel.org] On Behalf Of scm-j@nuntius.com Sent: Thursday, February 17, 2005 4:08 PM To: 'Klaus Darilion' Cc: serusers@lists.iptel.org Subject: RE: [Serusers] Fax problem with SER/Asterisk
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
A PSTN fax machine comes in to the Asterisk (via SIP or IAX. tested both ways but neither works), where the caller gets authenticated (via ANI or DTMF) and the destination leg of the call is originated by Asterisk to Level-3 via SER...
-----Original Message----- From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Sent: Thursday, February 17, 2005 9:46 AM To: scm-j@nuntius.com Cc: serusers@lists.iptel.org Subject: Re: [Serusers] Fax problem with SER/Asterisk
scm-j@nuntius.com wrote:
I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38
fax
relay.
According to Level-3 they think the problem lies in the Media Description field of the SDP message I am sending them. The problem
is
related to the Media Format sub-field (value 101) that I am
sending,
which according to them should be removed.
The SDP Media Description field I am sending, looks as follows:
m=audio 20744 RTP/AVP 0 101
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk -à SER -à Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and
prints a blank page.
My questions are as follows:
Could the Media Format 101 be the problem? If so, how do Iremove the 101? This change is probably in Asterisk, as it initiates
the
call, and not SER, or probably both.
I don't think that this will cause problem. If this is really the problem, than the L3 gateway su$%s.
If not, should I be looking elsewhere in SER/Asterisk to
solve
this problem?
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
regards, klaus
_______________________________________________ Serusers mailing list serusers@lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers
The behavior I have mentioned below is with the "dtmfmode=rfc2833" turned OFF in sip.conf. Level-3 did also mention about this. However, there is no change in the behavior where Fax calls either way (rfc2833 on or off) do not go through successfully. (I do restart asterisk when I toggle rfc2833 in sip.conf)
-----Original Message----- From: Vitaly Nikolaev [mailto:vitaly@voipsonic.com] Sent: Thursday, February 17, 2005 1:34 PM To: scm-j@nuntius.com; 'Klaus Darilion' Cc: serusers@lists.iptel.org Subject: RE: [Serusers] Fax problem with SER/Asterisk
.. I should found out by myself that you use asterisk :)
Same stuff... remove rfcxxxx from dtmf configuration in sip.conf
-----Original Message----- From: serusers-bounces@iptel.org [mailto:serusers-bounces@lists.iptel.org] On Behalf Of scm-j@nuntius.com Sent: Thursday, February 17, 2005 4:08 PM To: 'Klaus Darilion' Cc: serusers@lists.iptel.org Subject: RE: [Serusers] Fax problem with SER/Asterisk
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
A PSTN fax machine comes in to the Asterisk (via SIP or IAX. tested both ways but neither works), where the caller gets authenticated (via ANI or DTMF) and the destination leg of the call is originated by Asterisk to Level-3 via SER...
-----Original Message----- From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Sent: Thursday, February 17, 2005 9:46 AM To: scm-j@nuntius.com Cc: serusers@lists.iptel.org Subject: Re: [Serusers] Fax problem with SER/Asterisk
scm-j@nuntius.com wrote:
I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38
fax
relay.
According to Level-3 they think the problem lies in the Media Description field of the SDP message I am sending them. The problem
is
related to the Media Format sub-field (value 101) that I am
sending,
which according to them should be removed.
The SDP Media Description field I am sending, looks as follows:
m=audio 20744 RTP/AVP 0 101
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk -à SER -à Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and
prints a blank page.
My questions are as follows:
Could the Media Format 101 be the problem? If so, how do Iremove the 101? This change is probably in Asterisk, as it initiates
the
call, and not SER, or probably both.
I don't think that this will cause problem. If this is really the problem, than the L3 gateway su$%s.
If not, should I be looking elsewhere in SER/Asterisk to
solve
this problem?
How is the fax generated? A PSTN fax machine connected to asterisk? span_dsp?
regards, klaus
_______________________________________________ Serusers mailing list serusers@lists.iptel.org http://lists.iptel.org/mailman/listinfo/serusers
Hello.
I am working with level3 also... They require inbadn DTMF and you are trying to use rfc2833..
U have to change config of the whatever SIP UA you use from your side and configure it to use G711/inband DTMF
_____
From: serusers-bounces@iptel.org [mailto:serusers-bounces@lists.iptel.org] On Behalf Of scm-j@nuntius.com Sent: Thursday, February 17, 2005 12:33 PM To: serusers@lists.iptel.org Subject: [Serusers] Fax problem with SER/Asterisk
I am facing some problems with sending fax calls. I am using G.711 codec. However, my service provider (Level-3) does not support T.38 fax relay.
According to Level-3 they "think" the problem lies in the "Media Description" field of the SDP message I am sending them. The problem is related to the "Media Format" sub-field (value 101) that I am sending, which according to them should be removed.
The SDP "Media Description" field I am sending, looks as follows:
"m=audio 20744 RTP/AVP 0 101"
which is decoded by Ethereal as follows:
Media Type: audio
Media Port: 20744
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
My call is initiated by Asterisk which is sent to Level-3 via SER
Asterisk ---> SER ---> Level-3
The SIP call flow looks fine for the call. The sending fax sends the page and then gives an error. The receiving side gives me an error and prints a blank page.
My questions are as follows:
1) Could the "Media Format" 101 be the problem? If so, how do I remove the 101? This change is probably in Asterisk, as it initiates the call, and not SER, or probably both.
2) If not, should I be looking elsewhere in SER/Asterisk to solve this problem?
regards,
SCM
-
Klaus Darilion -
scm-j＠nuntius.com -
Vitaly Nikolaev