So you have a small home office or a few computers at home. Want to build a local area network to allow them to connect to each other? Occasionally, there are reasons for building a network without a router. Sometimes, to save money and other times for security.

Depending on what you want to do, there are a few options to build a local area network which doesn't involve buying a router.

The most common functionality for a network without a router is to be self-contained and have no point in or out. This is a secure network as it has no connection to the Internet and is good for keeping two or three computers linked up for sharing financial documents or a QuickBooks database.

We can connect two computers directly with a cross-over cable and have a LAN without a router. Computer 1 can access computer 2's resources, printers and file shares. Computer 2 can access computer 1's resources as well but this setup limits you to having only two computers connected.

If this is all you need, then you can connect the two machines up together and be good to go.

You can see an example of this setup below:

build local area network

To build a local area network with this setup, you will need to set both of them to have an IP address in the same subnet. A subnet is a group of machines that can call out to each other. For example, you can set one of your computer's IP address to be 192.168.0.1 and the next one as 192.168.0.2 or you could set one to be 192.168.1.100 and the other to be 192.168.1.101.

Make sure you use the subnet mask 255.255.255.0. By using this subnet mask, we can use any address between 192.168.1.1 through 192.168.1.254.

You can see the example shots below for a visualization of how the TCP/IP settings should be set up.

build local area network

The second computer should be set up like this:

build local area network without router

By keeping both machines in the same subnet, they can 'talk' to each other. In the example above, you can use 192.168.1.1 through 192.168.1.254 if you keep the subnet mask the same at 255.255.255.0.

Once this is set up, you can share resources on both machines and be able to access them by launching the Run window and entering the other computer's IP address in this format \\192.168.1.1, like so:

setting up a local area network

Now if you get a window that looks like this instead of the window above, you will need to setup your folder's security. You can do this by right-clicking on the folder you're trying to share/access and choosing Sharing and security. From here, you can give the appropriate permissions.

setting up a local area network

If you are using default accounts like Administrator on both machines, make sure both accounts have the same password. You can set the password by hitting Control + Alt + Delete and clicking on Change password. You can change it on that form. Then go ahead and try to connect again and this time, it should connect.

If you are using different user accounts, like 'Karl' on one and 'Sophia' on the other you will need to setup a 'Karl' and a 'Sophia' account on both machines with the same passwords. This usually does the trick.

Now if we want to print to a printer connected to the remote machine instead of connecting to a shared file, type in the IP address for the remote computer in the Run window and this time, choose Printers and Faxes like so:

setting up a local area network

Then by double-clicking on that folder you can double-click on any of the printers. That will open a printer window like below:

setup local area network

Your computer will add the printer and you will be able to use it from any application on your (local) machine.

We can also set up a wireless network without a router using something called ad hoc mode. To set this up, you will need to have a wireless card or adapter on each of your machines. You can connect up to 9 machines using this method.

Start by opening your Control Panel. Choose Network and internet connections. Next, click on Network connections and right-click on your wireless network adapter. It should be called Wireless network connection.

Choose View available wireless networks. On this screen, hit the Advanced button as you see in the screen shot below:

setup local area network

Next, click on the wireless network tab at the top of the window and then on add like shown below:

setup local area network

After hitting Add you will see this screen:

Make sure you tick the check box at the bottom of the screen to make the connection an ad hoc network. Then click OK. You will need to set up the IP addresses to be in the same subnet. You can refer to images in the beginning of the article on how to do that. Next, just connect to the ad hoc network from a client computer and you will be on the same network. You can then perform the same actions like we did above including Printer and file sharing.

I have done a MakeUseOf article in the past on how to setup a LAN with just a Windows Mobile Device here. Do you have another means of setting up a router-less network? We would love to hear about it in the comments!