Specifications

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Cisco Unity Express Voice-Mail and Auto-Attendant CLI Administrator Guide for 3.0 and Later Versions
OL-14010-09
Chapter 23 Configuring Your Cisco IOS Gateway for T.37 On-Ramp and Off-Ramp Fax Support
Deployment Scenarios
• The calling device sends a Calling Tone (CNG) tone, which identifies the calling party as a fax
device
• The called device sends a Called Station Identifier (CED) tone, which identifies the called device as
a fax machine
After the fax call is established, the devices identify the facilities and capabilities. The next phases are
transmitting the content, signaling the end of the transmission and confirmation, and releasing the call.
The Cisco IOS fax gateways support the following methods:
• Fax Pass-Through and Fax Pass-Through with Upspeed
• Cisco Fax Relay
• T.38 Fax Relay
• T.37 Store-and-Forward Fax
• IVR Applications for Fax
The T.37 Store-and-Forward Cisco IOS fax gateway uses the T.37 store-and-forward fax application,
which consists of two processes:
• On-ramp
• Off-ramp
These processes are shown in Figure 23-3 and explained in the following sections.
Figure 23-3 T.37 Store and forward Call Flow
On-Ramp Faxing
With the On-ramp process, a voice gateway handles incoming calls from the standard fax machine or the
PSTN and converts a traditional Group 3 fax to an e-mail message with a Tagged Image File Format
(TIFF) attachment. The fax e-mail message and attachment are handled by an e-mail server while
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On-ramp faxing Off-ramp faxing
Document Document
T.30
Fax to
e-mail
E-mail
to fax
Workstation
E-mail client
e-mail message
with text or
TIFF attachment
E-mail message
with attachments
T.30