Using The Fax Passthrough Feature; About Fax Passthrough - Cisco ATA186-I1 Installation And Configuration Manual

Using the FAX Passthrough Feature

Both ports of the Cisco ATA 186 support FAX transmission. The Cisco ATA 186
can send FAXes by either of two methods:
Note
Both the Cisco ATA 186 and the supporting gateway must be configured
appropriately to handle FAX signals.

About FAX Passthrough

To use the FAX passthrough feature, both the Cisco ATA 186 and the supporting
gateway must be configured at both ends to detect the FAX tone and switch codec.
The Cisco ATA 186 supports two G.711 upspeed methods for FAX passthorough:
OL-1267-01
• FAX passthrough—In this mode, the Cisco ATA 186 can detect a FAX tone,
after which it will turn off FAX tone detection and silence suppression and
switch its operating codec to G.711 u-law or G.711 A-law.
• G.711 FAX mode—In this mode, the Cisco ATA 186 simply passes the RTP
packets sent between the end FAX machines without any intervention. It
treats the FAX session like any normal voice call.
Limited fax passthrough support is available (up to 9.6 kbps fax
transmission rates for most fax machines). Extended support is
planned. Please check release notes and product bulletins for updates.
The Cisco proprietary codec switch using NSE packets and RTP detection.
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C H A P T E R
Cisco ATA 186 Installation and Configuration Guide
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