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New Member

Cisco 1721 and WIC-1DSU-T1-V2 configuration

I just purchased a refurbished Cisco 1721 router with a WIC-1DSU-T1-V2. I was able to connect to the console via serial and performed the initial setup for Ethernet0; however, I do not know where to begin to setup the WIC, and I don't want to pay for someone else to configure it if I can get the information here. My ISP gave me the following information (I am hiding the IP's for security reasons):

IP Address Allocation:

WAN-Side: bbb.bbb.bbb.bbb/30

Network IP: ccc.ccc.ccc.ccc

Broadcast IP: ddd.ddd.ddd.ddd

Subnet mask:

Available IP addresses: eee.eee.eee.eee-eee

Gateway IP (Router Address): fff.fff.fff.fff

The dmarc will not be extended to my server room until the end of the week.

My question is, once I plug the dmarc into the WIC, will the router automatically pull the information from the ISP? Or will I need to manually configure the WIC? If so, I would appreciate quick setup steps.

New Member

Re: Cisco 1721 and WIC-1DSU-T1-V2 configuration

Do you see the serial module when you perform a "show ver" or "sho run" command? If so, you need to know whether to configure for frame-relay or full T1 setup. You also need to find out the type of encapsulation the ISP is using on their end. I do not think the serial interface (WIC card)can be setup to get ip information from the ISP DHCP server like residential router can. Please provide more info so we can help further. Thanks.


New Member

Re: Cisco 1721 and WIC-1DSU-T1-V2 configuration

Hi David,

Thank you for your response. The router shows the following information when I perform the "show ver" command:

User Access Verification




Cisco1721#show ver

Cisco Internetwork Operating System Software

IOS (tm) C1700 Software (C1700-Y-M), Version 12.3(16), RELEASE SOFTWARE (fc4)

Technical Support:

Copyright (c) 1986-2005 by cisco Systems, Inc.

Compiled Wed 24-Aug-05 00:28 by ssearch

Image text-base: 0x8000816C, data-base: 0x80A654A4

ROM: System Bootstrap, Version 12.2(7r)XM1, RELEASE SOFTWARE (fc1)

ROM: C1700 Software (C1700-Y-M), Version 12.3(16), RELEASE SOFTWARE (fc4)

Cisco1721 uptime is 1 day, 15 hours, 50 minutes

System returned to ROM by power-on

System restarted at 11:01:07 UTC Thu Dec 28 2006

System image file is "flash:c1700-y-mz.123-16.bin"

cisco 1721 (MPC860P) processor (revision 0x100) with 28352K/4416K bytes of memor


Processor board ID FOC06170R7V (4141028887), with hardware revision 0000

MPC860P processor: part number 5, mask 2

Bridging software.

X.25 software, Version 3.0.0.

1 FastEthernet/IEEE 802.3 interface(s)

1 Serial network interface(s)


32K bytes of non-volatile configuration memory.

16384K bytes of processor board System flash (Read/Write)

Configuration register is 0x2102


When I perform the "sho run" command I get the following results:

Current configuration : 743 bytes


! No configuration change since last restart

! NVRAM config last updated at 11:05:02 UTC Thu Dec 28 2006


version 12.3

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption


hostname Cisco1721





enable secret 5 *******

enable password *******


no aaa new-model

ip subnet-zero

no ip routing




no ip cef





interface FastEthernet0

ip address

no ip route-cache

speed auto



interface Serial0

no ip address

no ip route-cache



ip classless

no ip http server


snmp-server community ********* RO


line con 0

line aux 0

line vty 0 4

password *******





The configuration is for a full 1.5 MB T1. I'm not sure of the encapsulation, but I believe it is HDLC. I am waiting for confirmation from my ISP.

New Member

Re: Cisco 1721 and WIC-1DSU-T1-V2 configuration

Hi Thomas,

You must know the details such as below and configure under "interface config mode":

-clock source (depends on your telco)

-framing and line coding (depends on your telco)

-timeslots (depends on your access bandwidth)

-and of course your IP address details

for more info click below;

Rate if this helps.



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