Home Automation Newsletters

A Simple PC Network

I've been asked often enough why I don't do more on data networking - what with the Cisco & Microsoft cert's people usually assume it's my strong point.  Whether that's true or not, I'd have to agree that it deserves more attention, so here goes!

Doing a home-based (or business-based for that matter) PC network is not really that difficult.  While there are different kinds of networks (Token Ring, Thinnet, Ethernet), 99.9% of us will use the latter: Ethernet.

Also called 10/100 Base-T, it's the simplest & least expensive standard you can use.  Actually, it's pretty rare to find a new installation that ISN'T ethernet!  In order to do yours, you'll need good ol' Category 5 (or higher) cabling, data jacks, a Punchdown Tool (advisable), RJ11/45 Crimpers and network cards for your computers.  Oh,... if you have more than two computers you'll also need a Network Router with built-in Switch. 

Cabling:

Let's start first with the cabling:  If all you want to do is connect two computers, your cabling simply runs from one machine to the other.   Otherwise, you need to run cabling from all your PC's to your hub/switch.  In theory, this is the easiest part!

Termination:

You're fired! - just kidding...
Termination refers to punching your wiring down into jacks or patch panels, or just using RJ45 connectors (they look like big 8-pin telephone connectors).  You can terminate your cabling in a couple of ways:

The simplest way (if you have the tools) is to just put RJ45 connectors on the ends of your cables.  This eliminates the need for jacks or patch panels & will save you a few dollars.  On the other hand, I think that wires sticking out of your wall (instead of from a jack in the wall) make for a not-so-clean installation - but if you do this you'll need to get your hands on a good set of crimpers.  And if you really want a clean installation and you're installing a lot of drops, you might want to consider actually using a Patch Panel.

It's better if you use Data (8-pin) Jacks at all your PC locations.  The jacks are all color-coded to make it a little easier.  After all, the big mystery for most people is the order of the wiring pin-outs (what order to punch the wiring down).

Speaking of pin-outs, below are the standards you should use (I'll explain in a moment).  As you look this over, bear in mind that white/green means a wire that's mostly white with green markings;  green/white = green wire with white markings, etc....

TW568-A

1. pin #1   white/green
2. pin #2   green/white
3. pin #3   white/orange
4. pin #4   blue/white
5. pin #5   white/blue
6. pin #6   orange/white
7. pin #7   white/brown
8. pin #8   brown/white

TW568-B

1. pin #1   white/orange
2. pin #2   orange/white
3. pin #3   white/green
4. pin #4   blue/white
5. pin #5   white/blue
6. pin #6   green/white
7. pin #7   white/brown
8. pin #8   brown/white

You don't even need to know this if you're using jacks at both ends, but you will if you're using the RJ45's (F.Y.I. - Ethernet will actually only use pins 1,2,3, and 6.  The other wires are unused).

Unfortunately, things get a little more complicated at this point in the discussion.  Most times you'll terminate your cable with the same standard (either one) at both ends - that's called a "straight-thru" connection - but occasionally you'll need to use 568-A at one end & 568-B at the other (a "cross-over" connection). 

If you're connecting two PC's directly, you'll need a cross-over connection between them. 

If you're connecting everything through a hub/switch, all your cabling will be straight-thru. 

If you have a DSL Router, it will connect to your hub via cross-over & all your other cabling should be straight-thru.  Also, some DSL routers have built-in hubs/switches.  In this case, your PC's connect to it with a straight-thru cable.

Now, let's assume that you have an internet connection that you want to share with your entire network.  If you're like most of us, your ISP is going to give you a single IP address - but that's only good for ONE computer!

Fortunately, there are several workarounds which can give all your networked machines access to the internet.  Microsoft introduced in Windows 98 "Internet Connection Sharing" (not my favorite solution).  Better though, if you have a DSL Router it probably has a feature called "NAT" (network address translation) built in to it.

NAT works by taking the IP address given you from your ISP, storing it in memory (sort of), and then allocating other private IP addresses to your machines.  It keeps track of, and translates the IP addresses, ports, etc.

Gets kind of complicated.  If you want to read more, you can go to the networking section for a tutorial on this and IP addressing. 

However, the really important thing about NAT and your DSL Router is that is provides a reasonable degree of "firewall" protection.  Especially important if you have an "always-on" connection, a firewall will help keep hackers out of your PC.  It's incredible how many people there are who are cruising for hacking opportunities....  By the way, you can also get software-based firewalls at pretty reasonable prices.

Once you have everything up and running (network cards installed successfully & connected), you're ready to share files & folders.  How you do that depends on your operating system, but I'm going to assume Windows 95/98 for the moment.

Go to "Start|Settings|Control Panel" and double-click the "Network" icon.  Make your primary network logon "Client for Microsoft Networks" in the dropdown window.  If it isn't there, click "Add|Client|Microsoft| Client for Microsoft Networks."  The other thing you'll want to do is click "File and Print Sharing" and check the boxes.   Restart your computer if you need to do so.

Sharing folders on the network is easy. Right-click on "My Computer" on your desktop, select "explore," and navigate to the folder you want to share.  Once you've found it, right-click on the folder and select "sharing."  You now have a dialogue for setting up your network share as you see fit!  You're done!  Within minutes of doing this, your folder will appear under "Network Neighborhood" on other machines with the rights you assigned (read-only or full-access).

And that's just about all you need to know to get up and running.   You'll find an abundance of informational resources on the web if you need to know more.  I've already mentioned networking, but if you're into seriously heavy stuff, check out www.Cisco.com for more than you ever wanted to know about IP addressing, routing, and still way too much more.

Back to blog