Chapter 1: Overview

Echo-Cancellation

Administrators connecting their Gateway Series appliances to the PSTN or other devices are likely to be placing calls that will result, at some point, in an unbalanced 4-wire/2-wire hybrid. The result of this hybrid is the reflection of a near-end echo to the calling party. Elimination of this echo is the responsibility of echo cancellation.

The Gateway Series appliance utilizes hardware-based voice processors for echo cancellation and codec transcoding. Its hardware echo canceller is designed to handle up to 128ms of echo cancellation across all channels and provides a G.168 compliant echo cancellation solution.

If not explicitly disabled in the Gateway Series web GUI, the hardware- based echo canceller will automatically operate and cancel all network echo within its tail range (1024 taps).

Digium, Inc.

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