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Cisco 1721 Router Application Question

I have two Cisco 1721 Routers and I'm looking to connect two remote sites via a dedicated T1. Can I setup my routers to be connected via the T1 with the WIC 1DSUT1 cards?

We also have a DSL modem going in at one of the sites for internet access. What would I need to add to the router to be able to interconnect the LANs at both remote sites and have all of the computers at both sites on the same network? As you can tell I'm new to all this. I'm in the process of completing my CCNA. Thanks for any help.


Re: Cisco 1721 Router Application Question

1. yes you can use the 1720s to connect the remote sites via a T1 circuit.

2. You could use a DSL Wic or an ethernet interface for the dsl modem. The DSL interface would be preferrable, because you can see the DSL interface go up and down. Otherwise, the modem dsl is down but the ethernet is up. The router can only see the ethernet up. This would be more of an issue if you add a backup link for your internet.

3. You need to run a routing protocol or use static routes to point across the T1.

Site with internet requires:

T1 Interface

Ethernet interface (connects to local switches)

Ethernet/DSL interface for Internet

Site without internet requires:

T1 Interface

Ethernet interface (connects to local switches)

Another option would be to forget the T1 connectivity.

Add an internet connection to the other site. Create a VPN tunnel across the connection for internal traffic. Internet would go out the local router.