Revised:  03/30/2002

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Network Your Home PCs

By: P. Bertram, mailto:pbertram@crl.com

If you have more than one computer at home, you may want to consider wiring them together into a local area network (LAN). Windows 95 is shipped with all the software you need to enable your computer to work in a LAN. Hardware prices are dropping fast and are now cheap enough that just about anyone can afford to put together a small LAN in their home or office.

Advantages of wiring your home computers together are that you can share your printer(s) and files between the machines. At my house, both my wife and I have computers in separate rooms. Before we wired our machines together, each had its own printer attached. If one of us wanted to print on a different printer than the one attached to our computer, we had to put the document on disk, walk it down the hall and load the document into the application to be printed. This "sneaker net" also required that both machines have the same application installed. Now we can just point and click to choose to which printer we want to print. We're making better use of the disk space we have on our separate machines and we are able to run groupware applications that allow us to share our schedules and address books.

Let me say that this will not allow you to run an application installed on another machine. In other words, you will not have control of the other computer's CPU. If you want to remotely control another computer you will need to get an application like PC Anywhere or one of the other programs written specifically to do that. This article describes how to wire your computers together for simple file and print sharing. (Using software you already have!)

The hardware for this project is not only cheaper now; it's easier to find. Most of the computer stores are now stocking networking hardware on their shelves.

You can buy an ethernet (network) card now for $20 or less...but be careful. You will be much happier and save a lot of time if you spend a little more and get a name brand ethernet card. The cheapest cards are not always reliable. A 16-bit card will do fine.

You will need to decide on the kind of wire you want to use. There are two basic choices: coax (thinnet) or unshielded twisted pair cable (UTP). For my installation, I used UTP. Foot for foot, coax will cost more and is harder to work with. The disadvantage to UTP is that if you connect more than two computers together, you will need a hub. A hub can cost $75-$100, more or less, depending on the brand and options.

To connect two computers together using twisted pair cable WITHOUT A HUB you MUST "crossover" some of the wires between the two machines. The reason for this is so that the transmit wires will connect to the receive wires on the other end and vice versa.

Besides the ethernet cards and the wire, you will need 2 patch cables and two RJ-45 jacks.

Most likely, the UTP cable you buy will have eight wires in it arranged as four pair of two wires. Be sure you buy category 3 or better. Cat 5 is best. Do not use cheap telephone wire, it won't work. Each wire will be color-coded. The "crossover" can be made at either end of the cable when you attach the RJ-45 jack to the cable end. One end of the patch cable will plug into the RJ-45 jack at the end of your cable. The other end of the patch cable will plug into the network card installed in your computer. Your total cable length cannot exceed 328 feet (100 meters).

Here's a diagram of the cable and connections between the computers:

(NIC*)-(patch cable)-(RJ45 jack)-(UTP cable)-(RJ45 jack)-(patch cable)-(NIC*)

*NIC=network interface card (ethernet card)

To make the "crossover" you must know how the pins are numbered on a jack and a plug and the difference between a jack and a plug. The jack is the female counterpart of the plug. Patch cables will have a plug at each end. A jack is a receptacle and a plug goes into the jack.

The 8 pins in a RJ-45 jack are numbered 12345678 as you look at the cavity in the wall or on the baseboard.

The 8 pins of a RJ-45 plug are numbered 87654321 as you look directly at the plug with the cable running away from you.

With that said, you will use only pins numbered 1,2,3, and 6. To make the crossover you must connect pin 1 to pin 3 and pin 2 to pin 6. You will do this on ONLY ONE END OF THE UTP CABLE. If you did it on both ends it wouldn't be a crossover.

If you are totally confused, go to: http://www.cis.ohio-state.edu/hypertext/faq/usenet/LANs/cabling-faq and study the diagrams.

I won't quote a color-code scheme because the cable/jacks you buy may have a different color scheme. In fact, there are three different standards in that department. You can study them at the above URL.

After you are crossed over and plugged in, it's time to configure your Windows 95 computers to talk to each other. Get your installation CD or disks ready because you will need some files from them.

After installation of your NIC, you will fire up your computer and Windows 95 will recognize the card and install drivers for it automatically. (We hope...you did buy a plug and play card, didn't you?)

Then go to control panel/network. Click add, then protocol, then netBEUI. Next, click add, then client, then Microsoft on the left then Client for Microsoft Networks on the right. Also, you should add file and print sharing for Microsoft Networks here.

For identification of your computer on your network, you must be sure that both computers belong to the same workgroup. If you don't, you will not be able to see the other in Network Neighborhood. You can put anything you like in the other 2 fields as long as both computers do not have the same name.

If you have a modem in your computer, you will see 'dial up adapter' along with your network interface card. If you use your modem on the Internet, TCP/IP will show up as a protocol bound to that adapter. That's OK for the dial up adapter, but you do not want TCP/IP bound to your network interface card. Check the bindings to make sure that only netBEUI is bound to the card and not TCP/IP. It doesn't matter if netBEUI is bound to your dial up adapter along with TCP/IP.

Finally, make sure your primary network logon is set to Client for Microsoft Networks and you have configured file and print sharing.

After you configure both computers and re-boot you should see the other computer in the window when you double click Network Neighborhood. Your 10baseT ethernet network is up and running. Use your W95 help files to learn how to share files and printers.

I'm obligated to say something about security and the Internet here. Once you enable file and print sharing and dial into the Internet, others may have access to your computer. To disable others from accessing your machine via the Internet you must disable file and print sharing before logging on to the Internet.

When you are ready to add more computers to your network and have purchased a hub, be sure and undo your "crossover".