Cisco Cisco Catalyst 6000 Multilayer Switch Feature Card MSFC2 Installation Guide

This guide describes how to connect Cisco high-density analog telephony network modules to your 
network. It contains the following sections:

The high-density analog telephony network module is a modular, high-density voice network module 
that provides dual tone multifrequency (DTMF) detection, voice compression and decompression, call 
progress tone generation, voice activity detection (VAD), echo cancellation, and adaptive jitter buffering.

The high-density analog telephony network module supports two different expansion modules, 
providing up to 12 ports in addition to the 4 Foreign Exchange Service (FXS) ports on the base 
high-density analog telephony network module (NM-HDA). See 

 for expansion module support 

information.