[asterisk-users] T.38 Fax With Flowroute SIP Provider

[Kevin P. Fleming]

On 05/06/2010 05:46 PM, Ryan Wagoner wrote:
> Does anybody have T.38 faxing working with Flowroute? I am running
> Asterisk 1.6.2.7-rc3 with spandsp 0.0.6-pre17. I can successfully
> receive faxes over ulaw. I enabled T.38 with t38pt_udptl=yes in
> sip.conf. When I receive a fax it tries to negotiate T.38 and
> Flowroute sends back a Bad Request response saying I have a SIP syntax
> error.
> 
> Flowroute support is recommending that I try again after removing
> externip and localnet from sip.conf. They state that their service
> will recognize the private IP and rewrite the SIP packets. However
> this is going to cause issues for my remote SIP phones.
> 
> Thanks,
> Ryan
> 
> DEBUG[32389] app_fax.c: Negotiating T.38 for receive on SIP/flowroute-00000000
> 
> INVITE sip:+number at xx.xx.xx.xx:5060 SIP/2.0
> ...
> CSeq: 102 INVITE
> User-Agent: Asterisk PBX 1.6.2.7-rc3
> Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO
> Supported: replaces, timer
> X-asterisk-Info: SIP re-invite (External RTP bridge)
> Content-Type: application/sdp
> Content-Length: 293
> 
> v=0
> o=root 2048302926 2048302927 IN IP4 xx.xx.xx.xx
> s=Asterisk PBX 1.6.2.7-rc3
> c=IN IP4 xx.xx.xx.xx
> t=0 0
> m=image 4575 udptl t38
> a=T38FaxVersion:0
> a=T38MaxBitRate:14400
> a=T38FaxFillBitRemoval
> a=T38FaxRateManagement:transferredTCF
> a=T38FaxMaxDatagram:1400
> a=T38FaxUdpEC:t38UDPFEC
> 
> SIP/2.0 400 Bad Request
> ...
> CSeq: 102 INVITE
> Error-Info: <sip:+number at xx.xx.xx.xx>;cause="[line 023] SIP syntax error"
> Content-Length: 0

Which line is 'line 23' of the T.38 re-INVITE?

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
skype: kpfleming | jabber: kfleming at digium.com
Check us out at www.digium.com & www.asterisk.org