Ricoh C3501 SIP T.38 Calls

Asterisk Asterisk Support
1

I’ve tried to get our Ricoh C3501 fax with T.38 SIP to work with Digium fax without much luck, even on a local connection.

There are two main things I’ve tried:

  1. Sending the Ricoh directly into the dial plan to be caught by the Receivefax application, and this is what I get.
    – Executing [fax@fax-rx:14] ReceiveFAX(“SIP/C3501-00000009”, “/var/lib/asterisk/fax-rx/fax-1-rx.tif,f”) in new stack
    – Channel ‘SIP/C3501-00000009’ receiving FAX ‘/var/lib/asterisk/fax-rx/fax-1-rx.tif’
    == Using UDPTL CoS mark 5
    – Got SIP response 406 “Not Acceptable” back from 10.10.170.45:5060
    [Mar 22 08:54:32] WARNING[27154]: res_fax.c:1619 receivefax_t38_init: error on ‘SIP/C3501-00000009’ while waiting for T.38 negotiation.
    [Mar 22 08:54:32] ERROR[27154]: res_fax.c:1867 receivefax_exec: error initializing channel ‘SIP/C3501-00000009’ in T.38 mode

  2. Sending the Ricoh through Asterisk to our PRI (Cisco 2651XM) and back to the PRI (with dial peer set up for T.38 relay with G.711 fallback) into ReceiveFax. This seems to get going OK then fails with a T1 timeout.

2

Here is the SIP DEBUG output showing what the Ricoh is rejecting.

[code]Retransmitting #1 (no NAT) to 10.10.170.45:5060:
INVITE sip:C3501@10.10.170.45;user=phone SIP/2.0
Via: SIP/2.0/UDP 10.10.177.20:5060;branch=z9hG4bK6aeb36f0
Max-Forwards: 70
From: sip:0419@10.10.177.20;user=phone;tag=as6d15047d
To: sip:C3501@10.10.170.45;user=phone;tag=7Atza4BfQe
Contact: sip:0419@10.10.177.20:5060
Call-ID: 20120323110829-T38-C-l3xKe@10.10.170.45
CSeq: 102 INVITE
User-Agent: Asterisk PBX 10.2.0
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
Supported: replaces, timer
X-asterisk-Info: SIP re-invite (External RTP bridge)
Content-Type: application/sdp
Content-Length: 263

v=0
o=root 1668554983 1668554984 IN IP4 10.10.177.20
s=Asterisk PBX 10.2.0
c=IN IP4 10.10.177.20
t=0 0
m=image 4141 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxDatagram:849
a=T38FaxUdpEC:t38UDPFEC

-- Got SIP response 406 "Not Acceptable" back from 10.10.170.45:5060

set_destination: Parsing sip:C3501@10.10.170.45;user=phone for address/port to send to
set_destination: set destination to 10.10.170.45:5060
Transmitting (no NAT) to 10.10.170.45:5060:
ACK sip:C3501@10.10.170.45;user=phone SIP/2.0
Via: SIP/2.0/UDP 10.10.177.20:5060;branch=z9hG4bK6aeb36f0
Max-Forwards: 70
From: sip:0419@10.10.177.20;user=phone;tag=as6d15047d
To: sip:C3501@10.10.170.45;user=phone;tag=7Atza4BfQe
Contact: sip:0419@10.10.177.20:5060
Call-ID: 20120323110829-T38-C-l3xKe@10.10.170.45
CSeq: 102 ACK
User-Agent: Asterisk PBX 10.2.0
Content-Length: 0
[/code]

3

You haven’t included the contents of the response. Not acceptable is supposed to contain additional information, atlhough I think this is rare in practice.

I wonder if it simply doesn’t like direct media?

4

Yeah, I think that would be helpful too. As far as I can tell, with both SIP and Asterisk debugging on, that’s all it’s telling me. I tried changing directmedia without any difference. I’m thinking of opening up a channel in the other direction to see what it offers asterisk, which might give me some insight into the parameters it likes. The Ricoh documentation isn’t helpful.

Thanks for the suggestion,

Chris

5

Interesting too that even if I do Set(FAXOPT(maxrate)=2400) in the dial plan right before the ReceiveFax it offers 14,400. It must be a transmit only feature. ECM is the same.