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<DIV><SPAN class=661215114-14082008></SPAN><FONT face=Arial size=2><SPAN
class=661215114-14082008>We have a Asterisk 1.4.17 set to receive calls from a
SIP provider. This company sends a INVITE directive which is new for me. It
encapsulates some T38 parameters, which make Asterisk fire a warning message, as
shown below:</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=661215114-14082008></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=661215114-14082008><STRONG>WARNING[31937]: chan_sip.c:5083 process_sdp:
Unsupported SDP media type in offer: image 58748 udptl
t38<BR></STRONG></SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=661215114-14082008>Please see the
complete INVITE directive:</DIV></SPAN></FONT>
<DIV><FONT face=Arial size=2><SPAN class=661215114-14082008><PRE><FONT size=+0><SPAN class=661215114-14082008><FONT size=2><FONT face=Arial><SPAN style="FONT-FAMILY: monospace"><SPAN style="FONT-FAMILY: monospace"></SPAN></SPAN></FONT></FONT></SPAN></FONT><FONT face=Arial><--- SIP read from 1<SPAN class=661215114-14082008>X</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.208:5060 ---><BR>INVITE sip:1130413900@1<SPAN class=661215114-14082008>X</SPAN>.2<SPAN class=661215114-14082008>XX</SPAN>.137.50:5060;transport=UDP;user=phone SIP/2.0<BR>f: <sip:1130799781@1<SPAN class=661215114-14082008>X</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.208:5060;user=phone>;tag=c0a-13c4-10e56f-53c614b4-10e56f<BR>t: <sip:1130413900@1<SPAN class=661215114-14082008>X</SPAN>.2<SPAN class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.50:5060;user=phone><BR>i: a15d7878d0838c0a13c410e56f42003c39eb3e0440c23d6f8-0542-4635<BR>CSeq: 1 INVITE<BR>User-agent: CS2000_NGSS/9.0<BR>P-Asserted-Identity: <sip:1130799781@1<SPAN class=661215114-14082008>X</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.208;user=phone><BR>Max-Forwards: 140<BR>k: 100rel<BR>Allow: ACK,BYE,CANCEL,INVITE,OPTIONS,INFO,SUBSCRIBE,REFER,NOTIFY,PRACK<BR>v: SIP/2.0/UDP CTA1CS2K:5060;maddr=10.140.131.208;branch=z9hG4bK-10e56f-42003c39-5dc0e7f6<BR>m: <sip:1<SPAN class=661215114-14082008>X</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.208:5060;transport=UDP><BR>c: application/SDP<BR>l: 414</FONT></PRE>
<DIV>v=0<BR>o=PVG 1218715242070 1218715242070 IN IP4 10.142.1.89<BR>s=-<BR>p=+1
6135555555<BR>c=IN IP4 10.142.1.89<BR>t=0 0<BR>m=audio 50556 RTP/AVP 18 8
101<BR>a=rtpmap:101 telephone-event/8000<BR>a=fmtp:101
0-15<BR>a=ptime:20<BR>a=fmtp:18 annexb=no<BR>m=image 58748 udptl
t38<BR>a=T38FaxVersion:0<BR>a=T38FaxMaxBuffer:1100<BR>a=T38FaxMaxDatagram:612<BR>a=T38MaxBitRate:14400<BR>a=T38FaxRateManagement:transferredTCF<BR>a=T38FaxUdpEC:t38UDPRedundancy</DIV>
<DIV> </DIV>
<DIV><-------------><BR>--- (14 headers 18 lines) ---<BR>Sending to 1<SPAN
class=661215114-14082008>X</SPAN>.1<SPAN
class=661215114-14082008>XX</SPAN>.1<SPAN class=661215114-14082008>XX</SPAN>.208
: 5060 (no NAT)<BR>Using INVITE request as basis request -
a15d7878d0838c0a13c410e56f42003c39eb3e0440c23d6f8-0542-4635<BR>Found peer
'GVTTRK01'<BR>Found RTP audio format 18<BR>Found RTP audio format 8<BR>Found RTP
audio format 101<BR>[Aug 14 12:00:22] <STRONG>WARNING[31937]: chan_sip.c:5083
process_sdp: Unsupported SDP media type in offer: image 58748 udptl
t38<BR></STRONG>Peer audio RTP is at port 10.142.1.89:50556<BR>Found audio
description format telephone-event for ID 101<BR>Capabilities: us - 0xe
(gsm|ulaw|alaw), peer - audio=0x108 (alaw|g729)/video=0x0 (nothing), combined -
0x8 (alaw)<BR>Non-codec capabilities (dtmf): us - 0x1 (telephone-event), peer -
0x1 (telephone-event), combined - 0x1 (telephone-event)<BR>Peer audio RTP is at
port 1<SPAN class=661215114-14082008>X</SPAN>.1<SPAN
class=661215114-14082008>XX</SPAN>.1.89:50556<BR>Looking for 1130413900 in
incoming_voxip (domain 10.213.137.50)<BR>list_route: hop: <sip:1<SPAN
class=661215114-14082008>X</SPAN>.1<SPAN
class=661215114-14082008>XX</SPAN>.1<SPAN
class=661215114-14082008>XX</SPAN>.208:5060;transport=UDP></DIV>
<DIV> </DIV>
<DIV><SPAN class=661215114-14082008></SPAN> </DIV>
<DIV><SPAN class=661215114-14082008>On the other end of this call, we have a
user agent which only accepts audio, via codecs such as G711, G729 and GSM. This
is fine, because we actually do not want to use FAX now, only want a
regular audio session. However, Asterisk keeps showing that warning message
everytime a new call arrives, which is quite annoying.</SPAN></DIV>
<DIV><SPAN class=661215114-14082008></SPAN> </DIV>
<DIV><SPAN class=661215114-14082008>We tried to enable SIP parameter <SPAN
style="FONT-FAMILY: monospace"><FONT face=Arial><STRONG>t38pt_udptl</STRONG> to
yes. In fact, the warning message has gone after that, but we started to
get the below error and the call is hang:</FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=661215114-14082008><SPAN style="FONT-FAMILY: monospace"><FONT
face=Arial></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN class=661215114-14082008><SPAN
style="FONT-FAMILY: monospace"><STRONG><FONT face=Arial><SPAN
class=661215114-14082008><FONT size=2><FONT face=Arial><SPAN
style="FONT-FAMILY: monospace"><STRONG><FONT face=Arial>ERROR[31937]:
chan_sip.c:12242 handle_response_invite: Got error on T.38 initial invite.
Bailing
out.</FONT></STRONG></SPAN></FONT></FONT></SPAN></FONT></STRONG></SPAN></SPAN></DIV>
<DIV><SPAN class=661215114-14082008><SPAN
style="FONT-FAMILY: monospace"><STRONG><FONT
face=Arial></FONT></STRONG></SPAN></SPAN> </DIV>
<DIV><SPAN class=661215114-14082008><SPAN style="FONT-FAMILY: monospace"><FONT
face=Arial>How do we get rid of that warning message, without
enabling <SPAN style="FONT-FAMILY: monospace"><FONT
face=Arial><STRONG>t38pt_udptl</STRONG> to
yes?</FONT></SPAN></FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=661215114-14082008><SPAN style="FONT-FAMILY: monospace"><FONT
face=Arial><SPAN
style="FONT-FAMILY: monospace"></SPAN></FONT></SPAN></SPAN> </DIV>
<DIV><FONT face=Arial><SPAN class=661215114-14082008><SPAN
style="FONT-FAMILY: monospace"><SPAN style="FONT-FAMILY: monospace">Thanks in
advance!</SPAN></SPAN></SPAN></FONT></SPAN></FONT></DIV></DIV></BODY></HTML>