The Cisco T1 DSU/CSU WAN interface card is an integrated, fully managed Data Service Unit/Channel Service Unit (DSU/CSU) for T1 or fractional T1 service. It is supported on the Cisco 1600, 1720, 2600, and 3600 Series Routers, and it provides a cost-effective router-DSU/CSU combination with the following features:
T1 or fractional T1 network interface
N X 64 kbps or N X 56 kbps non-channelized data rates (N = 1 to 24)
Standards-based, including ANSI T1.403 and AT&T Publication 62411
This module is used in many CCNA and CCNP kits and works well with the 1700, 2600 and 3600 series routers.