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Changing IP in the router/modem

Hi. We are upgrading our dsl to cable. We have a cisco 877 router/dsl modem and windows sbs 2003 r2. May I know how do I change the ip addresses in the router, and how do I add a cable modem to the router?


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Re: Changing IP in the router/modem

The 877 is a fixed feature device. That is, changing physical interface type requires using a different model. That said, one could put a cable modem "in front of" the 877 and just attach the two via Ethernet.

In general, changing an interface IP address is a simple set of commands after logging into the router directly in enable mode. Reference the configuration guide which will say something like:

Step 1

interface ethernet 0

Enters configuration mode for the Ethernet interface.

Step 2

ip address ip-address mask

Sets the IP address and subnet mask for the Ethernet interface.

Step 3

no shutdown

Enables the Ethernet interface to change the state from administratively down to up.

Step 4


Exits configuration mode for the Ethernet interface.

Hope this helps.