Wireless Home Network

Home Networking:
Wireless 802.11g/n and a Router

A description of the equipment you'll need with a special discussion about 802.11g/n.

Running multiple computers at one location connected to the Internet is becoming the standard, even in the home. I know lots of people who are trying to figure out what to do, how to do it and what to do when it doesn't work.

To help you understand your options, and see where the future might be, I decided to show you what most homes would have. I'm not endorsing any specific vendor - I haven't done an exhaustive search, there are always newer devices available, etc., but I think being specific about one configuration that a person actually is using helps the most.

Overview

Here is a diagram of a typical setup. A cable modem connected me to the Internet and a router with 4 ports. There's usually one or more PC's connected to the router by 10BaseT wire and a laptop and/or an awkwardly located wireless desktop connected to the router either by a wire and a standard 10BaseT LAN card or to the wireless access point via a pc-card and a USB networking device ...

Let me walk through this in detail.

Cable Modem

Most have a cable or DSL modem from a local provider. Your provider claims 1.5Mbit per second maximum 300Kb maximum (you can get higher bursts at off-peak hours, half that when it's busy). They charge around $40 a month.

The cable modem gives you a place to plug in a LAN cable with an RJ-45 connector just like any 10BaseT Ethernet port on a LAN. The cable modem expects a single network interface adapter with a particular (MAC) address on the other end of the LAN cable you plug into it. The cable modem makes that single LAN connection appear to the Internet as a single IP address. Normally that adapter is in a single PC.

Router/Switch

The router has such an adapter to connect to the cable modem, but it also has one or more other places to plug in other LAN connections (it is a network switch with respect to those other cables). The router gives devices connected into its LAN connections their own individual IP addresses (local ones) and translates them in a way so as to share the single external IP address that is available through the cable modem. This is called Network Address Translation (NAT). In the process of doing this, most home/SOHO routers like the one I have also act as firewalls controlling access from the Internet outside to the network inside.

There are many different makes, but illustrated here is a Linksys BEFSR41 4-Port Cable/DSL Router. Here's what it looks like on the floor under a PC with the power and other cables coming out of it:

You can configure this router by connecting a PC to it with a 10BaseT connector and using a browser displaying a particular URL. You can set all sorts of parameters. The instructions tell you how to set it up. (The defaults are fine for most everything.)

When you configure your router you may find out that you can specify that it pretend to your cable modem that it's any MAC address you want. This lets you add the router to your computer setup without needing to tell your cable company you have a new adapter address - you just make the router pretend it's your PC's address. (The router uses a different, unique address to your inside network.)

The router/switch can control a LAN in your home/office. You just plug computers into it using 10BaseT cables and they are connected to the Internet for browsing, email, etc. Some bring their laptops home from work or a trip and plug it in and things seem to just work with no new settings.

Since the computers connected to it are on a common LAN, you can share printers, hard-drives, zip drives, etc., just like any other LAN.

Until now most folks had used Windows' Internet Connection Sharing for networking and it was a nightmare to configure. That's something implemented in software built into Windows starting with Windows 98.

(You can add it by going to the Control Panel's Add/Remove Programs section, clicking on the Windows Setup tab, and looking at the Details of Internet Tools to make sure that Internet Connection Sharing is installed.) Windows Internet Connection Sharing requires you to have two network cards in your computer (or a dial-up connection and a LAN card). It connects to the Internet on one and to a LAN on the other. It only works when the connected computer is running, and most people found that it slowed overall connections some with its overhead. The router is a much cleaner solution, and usually has a built-in hardware firewall for added protection and eliminating the need for a software firewall.

Until now most folks had used Windows' Internet Connection Sharing for networking and it was a nightmare to configure. That's something implemented in software starting with Windows 98.

Wireless: 802.11b/g

While many offices are fully wired, most homes are not. Rather than mess up your walls and spend hours pulling cables or pay an electrician lots of money, you may decide to use wireless.

A type of wireless system that is extremely popular is called 802.11g or Wi-Fi. It runs up to 154 Mb/second, about as fast as a normal 10BaseT LAN and much faster than a 1.5Mb/second (maximum) cable modem.

You got to try using that type of system at the PC Forum and Agenda conferences, and at Fall Comdex 2006 that it is becoming a standard of choice all over the place in business, education, and the home. Walt Mossberg recommended it in one of his columns. Microsoft and Mobilestar are putting it in Starbucks.
Wayport is putting it in airport lounges and hotels around the USA. You should decide to buy equipment that conforms to that standard. The current standard is 802.11g, which is 15 times faster than that.

802.11b/g sounds like a very techie term, but it isn't. It's just the name of a particular specification for wireless networking from a group that likes to use numbers for names, the IEEE Standards Association.

They have lots of specifications with numbers for names. "647" is the Standard Specification Format Guide and Test Procedure for Single-Axis Laser Gyros. "802" is the Local Area and Metropolitan Area Networks standards (LAN/WAN). Within that, "802.3" is Ethernet, "802.5" is Token Ring, etc., and "802.11" is Wireless LAN. "802.11b/g" is a particular version referring to 2.4GHz radio using Direct Sequence Spread Spectrum and CSMA/CA that runs at up to 154 Mb/second. To learn more about 802.11b/g, you can read a 3Com whitepaper about 802.11b or take a look at the Wireless Ethernet Compatibility Alliance web site (especially their whitepapers and glossary). That Alliance is trying to get the name Wi-Fi accepted as a common term for 802.11b (and a trademark

Wireless Access Adapters

After buying your wireless 802.11g router, to make any part of your LAN wireless you need what's called a Wireless Adapter for each of your computers. Most common are the pccard for laptops, wireless NIC's for desktop and wireless USB adapter in awkward areas. The wireless adapter connects to your LAN like any other device and then lets any computer connected to it wirelessly act as if it were on the same LAN.

Here's a picture of a typical unit (a Linksys WAP11):

You configure the settings in the unit by either connecting a computer to it with a USB connector (some other vendors use serial) or on the local LAN with a utility they give you. The default configuration worked fine, though you can end up making some modifications to make the system more secure. You need to set the name of your ESSID (your logical wireless LAN). This can be most any name or you can keep the default (usually that default "Linksys" or whatever router you have -- surprise!). You should enable encryption (Wire Equivalent Privacy, or WEP) by setting a series of keys. In some units you type in a phrase and it uses that to give you a series of hex digits that make up the key. It takes a couple of minutes to configure.

Wireless Adapter Types

To connect wirelessly, your PC or laptop needs a wireless adapter. Typical is a 3Com Wireless AirConnect PC card. It is a normal PCMCIA Type-II card that goes into the slot in you laptop just like a LAN card. It may have an antenna that sticks out:

You install the PC card like any other PC card. It needs a driver. In this case after after getting the LAN set up you should download the latest drivers and firmware for the card from the Manufacturers web site and upgraded your system. When you configure the driver you type in the ESSID (Wireless LAN Service Area name) and the encryption key information. That's it. Everything else seems to just work - mostly!

Your PC card may come with some utilities, such as one that displays the signal strength in real time. Here is a picture of that utility at one point when the signal wasn't so good and it automatically slowed down to 5.5Mb/second. Next to it is a picture taken outside of a laptop over 150 feet away from the house (the wireless access point is next to an outside wall, inside the house). You can see a website on the screen (this wireless stuff really does work!):

There are adapters for desktop PCs that let you use the wireless PC cards. You plug the adapter boards into a PCI slot and then plug the same type of card you use on a laptop into that board. There's also USB devices available as well.

Realities of wireless

While it all generally works, you have to remember that this is wireless, just like cell phones, walkie talkies, etc... Line-of-sight outdoors can work quite a distance, but indoors, with walls and electrical devices, you get more interference and much less obvious coverage patterns. (For example, the area on the other side of a wall behind bricks can be a dead zone, just 10 feet from away reception can be just fine.) Also, other 2.4GHz devices, like some cordless phones and the upcoming Bluetooth devices, can cause temporary gaps in operation. Periodically you may have to click on a link a second time. You can also optimize the location of your router and/or wireless access point. Higher is better I hear. Still, it is pretty useful. It's great checking email along with the newspaper at breakfast without any wires. If you see something you need to print out, just click on "Print" and soon you'll hear the faint sounds of the printer in the other room on another PC doing its thing.

Some hints: Folks who have their Internet access coming into the basement and therefore put their wireless access point in the basement report poor reception in other parts of the house. Some vendors' access points are more effective than others (I don't know which), so ask around. Within a house, if you don't have great placement, think of it like shouting: voices don't carry through too many walls, and local wireless is like shouting. Remember what cell phone service is like in many buildings: Some rooms are dead zones, other places are OK. Building materials and antenna placement matter. As an example, read about David Coursey's struggles with 802.11b in his home in his AnchorDesk essay.

Setting it all up

Setting this all up is not very hard - no more so than most any other multi-part PC accessory setup, like a PDA with synchronization or a peripheral with special software. Just don't forget to buy the cables and have enough places to plug things in...

Approximate cost today: Wireless 4 port 802.11n Router - $40 to $150, Wireless Access Point - $100 to several hundred, Wireless PC card/s for your laptop/s - $40 to $180 each (most new laptops come with built-in Wi-Fi these days), desktop PC PCI wireless adapter/s - $60 to $110 (you need to add one of the cards to each desktop computer). There are various combination devices (router/wireless access points) and bundles (including some cards) available so shop around for bargains. Several companies are making these, with new ones announced all the time. Prices have really dropped in the past year. Don't buy 802.11n at this point. 802.11n is very cheap and much faster & more reliable.

I hope this information helps you decide what to do for your home network setup.

Home Networking FAQ's (2 .PDF's in 1 zip file )
How to Secure Your Wireless Home Network with Windows XP (external link)

Updated: November 18, 2010