Proper Network Design

Setting up a network of computers is a lot of fun, even if you’re getting paid to do the job. But maintaining, and using, a properly designed and setup network is a lot more fun than maintaining, and using, an improperly designed one. Be aware of some common pitfalls. Proper design, in many cases, is cheaper, and less complex, in the long run.

  • Cabling. Making your own Ethernet cables may look like fun, but it’s not.
  • Grouping. Setting up a domain is not for everybody, but it will make your life easier in many ways.
  • Networking. Using a NAT router for connecting just one computer to the Internet, or for connecting just 2 computers to each other, is cheaper and safer in the long term.
  • Wired or Wireless LAN? Using WiFi is great – when you truly need it. But know the limitations.


Ethernet Cabling – It’s Not A Good First Time Project
An Ethernet cable is more than a simple group of small wires – it’s actually an electrical system in its own right. The specifications for a 10M Ethernet cable are pretty complex – for 100M cable, you have to be more careful. And Gigabit Ethernet cable requires special equipment.

If you’re a professional, and setting up a large office, hire an experienced and licensed electrician. If you’re setting up your own small network, whether for a small office or for your home, and you’re just starting with Computer Networking, buy premade, and tested, cables at a computer store.

Don’t learn computer networking starting with making your own cables. Setting up an infrastructure, using reliable cabling, is cheaper, and easier in every respect. Don’t start with do-it-yourself Ethernet cabling, when you’re setting up a network.


Domain vs Workgroup – A Little Effort Can Go A Long Way

Every Windows computer will act as a server, but only computers running a true server Operating System – Windows 2000 Server, or Server 2003 – can provide a domain. And setting up a domain is not a good project for your first network. But domains have their advantages as well as disadvantages.

If you have any network expertise, and a server operating system, consider setting up a domain. It’s good for you, in the long run.


Networking Computers Is Cheaper, and Simpler, With a NAT Router
If you have one computer, sitting in your office, and connected to nothing, you have just one computer. If you connect that computer to the Internet, or to another computer, you have a piece of, or the beginning of, a network.

  • The simplest way to connect your single computer, to the Internet, is to connect the modem (Cable, dial-up, or DSL), externally, to your computer. Or install the modem internally.
  • The simplest way to connect your two computers, to each other, is to connect them using a cross-over cable.

In neither case is this true, in the long term.

  • Using a NAT router to connect as few as one (as well as multiple) computers, to your Internet service, is an essential component in layered security.
  • Using a NAT router to share Internet service, between as few as two (as well as multiple) computers, is almost as cheap as using ICS. And it’s far simpler. ICS was a good idea long ago, but it’s not today.
  • Using a NAT router to connect your computers, and / or to share your Internet service, is easily scalable. When you get your second (or third or whatever) computer, just plug it into the router. How do you do that with ICS and a cross-over cable?

When you get your first computer, buy your first NAT router. You’ll be glad you did, in the long term.


Choosing A Wired or Wireless LAN Is An Important Decision
When you setup a network of computers, in your home or small office, a mass of Ethernet cables running everywhere can be a problem. WiFi, or Wireless networking, can provide relief from the mass of cables. But WiFi is NOT a replacement for Ethernet, for many reasons.

  • Scalability. With a 100M Ethernet cable, you could have up to 200M of data flow (with send and receive simultaneously), between a single pair of computers. Each pair of computers in your office can conduct a separate, yet simultaneous, 200M conversation.

    With 54M WiFi, all of the computers in your home or office, and all of the computers in your neighbors home or office, will all share the same 54M channel. Actually, there are 3 54M channels – but if you have even 1 neighbor, chances are that you’ll have more than 3, so you’ll have to share with at least one other network. And all of your computers will share that one 54M channel. With 108M Super-G, moreover, there is just one channel in total, shared by everybody, in the entire neighborhood.

    MIMO, aka 802.11n (“pre-N”), is being advertised to improve your bandwidth / extend the range of your WiFi network. But at what cost? MIMO, and antenna diversity, is passive, and increases your range based upon eliminating multipath interference. MPI decreases the usability of an already weak signal; MIMO simply eliminates the effect of MPI. If you simply have a weak signal, and no MPI, a simple MIMO router won’t help you.

    If your MIMO router also uses beamforming, you can increase the range of your WiFi signal, by dynamically aiming it towards your WiFi client, similar in effect to a high gain directional antenna. And all that does is push a stonger signal in the direction of your neighbors. If your neighbor has a MIMO router, and you are on the other side of his WiFi client, your router will have more interference to deal with.

    If you get a MIMO router that does beamforming, and your router and client are in the same line with your neighbors MIMO router and client, you’ll be fighting each other, and with more interference. If your WiFi client is in another direction, you’ll be pushing your signal towards yet another neighbor.

    In short, neither MIMO nor Super-G are products which will be useful in neighborhoods of any density.

    And there are other factors which will prevent you from getting an actual 54M of data flow.

  • Security. Ethernet cables stay in your home or office – when you lock your door, your cables, and computers, are secure. The WiFi signal, on the other hand, travels thru your walls, and down the block, to your neighbors computers. You have to use extra security precautions, with a WiFi LAN.
  • Stability. Your WiFi neighbors will come and go, constantly. You have WiFi devices politely, and impolitely, sharing the channel. And, you’ll have noise on the channel. Noise can come from many electronic sources.
    • Baby monitors.
    • Computers.
    • Cordless phones.
    • Microwave ovens.
    • Wireless stereo speakers.

If you truly need WiFi, then use it. The convenience of surfing the Internet from your bedroom is great. But know the limitations of WiFi, before investing a lot of time, and money, needlessly. For many LANs, Ethernet cabling will always be a better solution.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: