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Combining two networks into one

Not sure if this is the right forum but we will try.

I have two separate closed networks, both with an ip range of, with a large number of devices in each net so that I cannot combine them into one. We shall call them NetA and NetB.

I have a Point 2 point connect to NetA using a pair of Cisco 1841 routers. For each router, I have Slot 0 populated with a WAN 10/100 card to support the P2P. On my end of the p2p, i have used both FE0 and FE1 to provide to access lines, with FE0 being subnet and fe1 being This has been working just fine for us for over a year.

I now have NetB access via a dedicated fiber. Have the fiber running into a switch, and then we have a laptop on the switch that lets us administer the network and devices.

What I want to do now is to somehow bring these two networks together into one router, and then be able to translate NetB to a different subnet( for example). My ultimate goal is to be able to use one workstation (with one nic) to support both nets. So, if at my workstation I type,I get NetA. If I type, I get NetB

So, I'm looking for ideas as to the most efficient way to service both of these networks from one workstation. If I have two have two nics with different IP addresses, then so be it. However, if I can bring the p2p into a different style router that can also have the fiber connection without using a fiber converter to take it to copper, then even better.

Any and all suggestions welcome. And as I said, I cannot change the IP ranges on either subnet due to vendor hard coding and the number of devices being used.




Re: Combining two networks into one

You should be able to NAT one of the networks on the router interface. Use the 'network' option for NAT to translate the whole /24 with one statement.


Community Member

Re: Combining two networks into one

I have been unable to verify if the 1841 will support 2 HWIC cards at once. I know that it has two slots, but, can it handle 2 HWICs for input at once?


Re: Combining two networks into one

The following page states that both slots on the Cisco 1841 router are HWIC slots. If you scroll further down you will find a list of compatible HWICS in table 6.

Here's the URL:



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