Cisco Cisco 1900 2900 3900 Series 8-Port Gigabit Ethernet HS-WIC with PoE Installation Guide

This document describes Cisco serial and DSU/CSU high-speed WAN interface cards (HWICs) and how 
to connect them to a network. It contains the following sections:

For an overview of Cisco interface cards used for Cisco access routers, see the 

 document.

This section describes T1/FT1 data service unit/channel service unit (DSU/CSU) HWICs and how to 
connect them to a network. It contains the following sections:

The 1-port T1/fractionalized T1 (FT1) DSU/CSU HWIC (HWIC-1DSU-T1) includes an integrated 
DSU/CSU. The HWIC can be configured for either full T1 services or fractionalized T1 services.

 shows the T1/FT1 DSU/CSU HWIC LEDs and loopback button. 

 describes the functions 

of the LEDs and loopback button.