Specifications

6-16
Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide for SCCP (version 3.0)
OL-4652-01
Chapter 6 Configuring and Debugging Fax Services
Debugging the Cisco ATA 186/188 Fax Services
PATH: 2.116:10002 => 2.213:10000
[ 26]Codec G723
[ 101]Codec G711u/D
[ 102]NSE PT 100, EVT 192: Up-Speed, CED tone Detected
[ 103]NSE PT 100, EVT 193: ECAN OFF, Phase Reversal Detected
This summarizes the fax events for each path.
The audio stream events reported by rtpcatch include:
– beginning of new audio codec
– silence packets
– lost packets
– erased packets (as in G.729)
The NSE events reported by rtpcatch include:
– event 32, Fax Mode, CED tone Detected (RFC2833)
– event 34, Modem Mode, ANSam tone Detected (RFC2833)
– event 192, Up-Speed, CED tone Detected
– event 193, ECAN OFF, Phase Reversal Detected
– event 194, ECAN ON, Silence Detected
– event 200, T38 Fax Mode, V.21 Detected
– event 201, T38 Fax Mode ACK
– event 202, T38 Fax Mode NACK
– event 203, Modem Relay Mode, CM Tone Detected
– event Cisco Fax Relay (with RTP payload type 96)
– event Cisco Fax Relay ACK (with RTP payload type 97)
Analyzing rtpcatch Output for Fax Sessions
The following examples show the proper fax events when gateways are configured to operate in the
following modes:
• Cisco ATA fax mode
• Cisco ATA fax pass-through mode
• T.38 fax relay mode
• Cisco fax relay mode
Example 6-1 Fax Mode
---------- FAX Summary 1 ----------
[ 25]<2.131=>3.200> Codec G711u
[ 26]<3.200=>2.131> Codec G711u
Analysis
Both sides use G.711 for the entire fax session.