Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

SPA 2102, and faxes to the protocol T38

(Prefer Alberto Montilla)

Good day!
We test equipment SPA2102 and we have problems in passing faxes.
Fax works only in automatic mode without raising a voice session.
Fax does not go with the reference in the manual mode on a protocol T38.
When I try to connect an error: T38 Decode UDPTL error, enclose a part of syslog.

Syslog, schema and configuration are attached

Thanks

Best Regarde

Max

  • ATAs Gateways and Accessories
11 REPLIES
Cisco Employee

Re: SPA 2102, and faxes to the protocol T38

Dear Max;

This should work as we have plenty of deployments with the AS5350 and SPA2102 using T38, so I suspect this is a configuration issue.

Are you able to get a network trace (e.g. ethereal or wireshark) so that we see a bit more details?

regards
Alberto

New Member

Re: SPA 2102, and faxes to the protocol T38

Hello Alberto,

Attach syslog and wireshark c voice configurations.

We use a Cisco 827, NSGate, etc. and problems with faxes not have, but they are removed from production.
New Member

Re: SPA 2102, and faxes to the protocol T38

Next, attach wireshark from another fax machine:
Wireshark not the last fax. Pcap - this shot when you send a fax in manual mode after the voice session (failed).
Wireshark the last fax. Pcap - this shot when you send in an automatic mode (Was).

New Member

Re: SPA 2102, and faxes to the protocol T38

Dear Alberto.
We now tested SPA2102, using codec g726r16-32, problems with passing faxes did not exist, all the correct switches to a protocol T38.
We need to use the codec as g729r8 us critical bandwidth.

If you want I can send wireshark.

Thanks

Best Regarde

Max

Cisco Employee

Re: SPA 2102, and faxes to the protocol T38

Hi Max;

Thanks for sending. Will have a look and let you know.

Regards

Alberto

Cisco Employee

Re: SPA 2102, and faxes to the protocol T38

Hi Max;

Please try the following changes:

(1) On the SPA2102 please change the following:

[Line 1]  FAX Tone Detect Mode: Caller

(2) On the AS5350 make sure the following parameters are set:

fax protocol T38
fax rate voice
fax-relay ecm disable
fax nsf 000000

no vad


Please let me know whether this works. Please test outgoing and incoming faxes.

Regards
Alberto

New Member

Re: SPA 2102, and faxes to the protocol T38

Hi Alberto,

On the Cisco 5350 settings are:

dial-peer voice 3808102 voip
description ### Test ###
max-conn 2
destination-pattern 3808102
session protocol sipv2
session target ipv4:172.16.53.240
incoming called-number 3808102
dtmf-relay rtp-nte
fax-relay ecm disable*
fax nsf 000000*
fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback none*
no vad*

At SPA 2102 setup as follows: Linksys SPA Configuration g729.mht

Fix wireshark:

1. in manual mode - is not passed (spa g729 in manual mode.pcap)

2. in automatic mode - has been(spa g729 in automatic mode.pcap)

New Member

Re: SPA 2102, and faxes to the protocol T38

And the same thing only on G726r32,

Only now, the setting in this mode:

FAX Tone Detect Mode: caller or callee

:

On the Cisco 5350 settings are:

dial-peer voice 3808102 voip
description ### Test ###
max-conn 2
destination-pattern 3808102
session protocol sipv2
session target ipv4:172.16.53.240
incoming called-number 3808102
dtmf-relay rtp-nte
codec g726r32 bytes 40
fax-relay ecm disable
fax nsf 000000
fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback none
no vad

At SPA 2102 setup as follows: Linksys SPA Configuration g726r32.mht

1.in manual mode

2.in automatic mode

Faxes are fine, so would the same thing only on the g729

Best Regards,

Max

Cisco Employee

Re: SPA 2102, and faxes to the protocol T38

Hi Maxim;

I'm escalating the issue. I'm not sure what the problem is at this stage. As soon as I get a resolution I'll let you know

Regards
Alberto

7582
Views
0
Helpful
11
Replies