Specifications

6-18
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
Example 6-5 Cisco Fax Relay
---------- FAX Summary 1 ----------
[ 8]<2.53=>3.99> Codec G711u
[ 248]<3.99=>2.53> Codec G711u
[ 798]<2.53=>3.99> NSE PT 96, Cisco Fax Relay
[ 799]<3.99=>2.53> NSE PT 97, EVT 192: Up-Speed, CED tone Detected
[ 800]<2.53=>3.99> NSE PT 97, Cisco Fax Relay ACK
[ 801]<2.53=>3.99> Codec C_FxRly
[ 803]<3.99=>2.53> NSE PT 96, EVT 192: Up-Speed, CED tone Detected
[ 804]<2.53=>3.99> NSE PT 97, Cisco Fax Relay ACK
[ 805]<3.99=>2.53> Codec C_FxRly
Analysis
• Both sides initially use G.711µ-law.
• NSE signaling packets are sent between <2.53> and <3.99>.
• Both sides switch to Cisco fax relay.
Using rtpcatch to Analyze Common Causes of Failure
The following examples show the rtpcatch output of failed fax sessions. <3.200> is ATA; <2.53> is a
Cisco gateway.
Example 6-6 Cisco ATA Configuration Failure
---------- FAX Summary 1 ----------
[ 37]<2.53=>3.200> Codec G723
[ 39]<3.200=>2.53> Codec G723
Analysis
• <2.53> is the originating gateway and <3.200> is the terminating Cisco ATA.
• The Cisco ATA and the <2.53> gateway use G.723 codec.
Possible Causes for Failure
• The Cisco ATA is not configured with fax mode or fax pass-through mode.
• If the Cisco ATA is the gateway for a fax sender, the remote gateway is not configured with fax
pass-through mode.
Example 6-7 Fax Mode Failure
---------- FAX Summary 1 ----------
[ 37]<2.53=>3.200> Codec G711
[ 39]<3.200=>2.53> Codec G711
[ 1820]<2.53=>3.200> NSE PT 96, Cisco Fax Relay
[ 1966]<2.53=>3.200> NSE PT 96, Cisco Fax Relay
Analysis
• <2.53> is the originating gateway and <3.200> is the terminating Cisco ATA.
• The Cisco ATA and the <2.53> gateway begin with G.711 codec.
• The <2.53> gateway sends Cisco fax relay event packets.