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We are all still adjusting to the impact the World Wide Web has had on our personal and professional lives. It can instantly deliver unlimited amounts of information, on just about every imaginable topic, right to our desktops. There was (until recently) just one limitation: you couldn't access the internet unless you were physically plugged into it.

Wireless networking technology has come to the rescue and banished this limitation. Wirelessly enabled portable computers and PDAs now let you roam your office, your home, and even many public areas, and still be connected to your e-mail and the Web.

Wireless connectivity offers endless exciting possibilities. In an office setting you are not confined to your desk. You can take your laptop to a meeting room and have full access to all local server or Web based information. In either home or office settings you can easily connect multiple computers and printers, without the hassle of running cables through walls and ceilings. You can even stay connected in many public places, including coffee shops or restaurants, hotels or conference centers, airport terminals, and even on a sidewalk or when you are stuck in a traffic jam.

What is making all this possible? Cheap and easy to use wireless technology has hit the mainstream. You can buy the hardware for a simple wireless network for under $100. Even a non-techie can easily install and configure this hardware with relative ease (although properly securing it is another matter- see Turning On Security is a Must below).

This articles reviews the basics of wireless hardware and technologies. It includes a review of the basic hardware, and an explanation of the various standards.

Building a Wireless Network
On the hardware side, wireless networking starts out with an access point or AP. The AP plugs into your wired network (likely an Ethernet network at work, and your cable or DSL modem at home). The AP has an antenna which broadcasts data via radio waves to a receiver in a wireless network interface card in your laptop or PC. In the case of a laptop the wireless NIC can be built-in or on a PC Card, and in the case of a desktop, it will be in a standard PCI card.

You may need to work with your ISP to configure your modem and the AP. You may want to get an AP that is also a router. This will allow you to share a single connection to the internet with all wired and wireless computers on your network. Some APs also include a firewall.

In many cases a single AP will suffice in an average size home or apartment. As a starting point you will want to keep your AP as close as possible to your broadband connection. Keep in mind that the radio signal will radiate in a spheroid shape from your AP. Thus, placing the AP on the main floor of your house may allow it to reach both the basement and the second floor, and even your backyard. Floors, walls and ceilings will act as barriers to the signal. The signal will go through simple plaster walls with relative ease. Stone or brick walls can greatly reduce or even completely block a signal, and glass will reflect it. Large metal objects (refrigerators and even you PC case) can block a signal as well. Ultimately you will likely have to experiment with the location of your AP to eliminate dead spots and get maximum coverage.

After physically installing the hardware, you will have to configure it. This is usually relatively easy. Most wireless hardware comes with set-up wizards that walk you through this process.

So Many Standards!
When you go to purchase your AP, you will likely be overwhelmed by the available choices. Sorting out what wireless option is best for you will require some thought as there are variety of wireless standards to choose from. There are currently 3 wireless standards approved by the Institute of Electrical and Electronics Engineers (the "IEEE" or "I-triple-E"). IEEE standards dictate how wireless hardware must operate, with the end result being universal hardware compatibility and interoperability for any given standard (and in some cases, for multiple standards - read on). You need to understand these standards so that you can make sure that the wireless devices you purchase will be compatible with each other, and will work in the way that you need them to. There are basically three wireless-networking standards you can choose from, 802.11b, 802.11a and 802.11g. You should also be aware of a fourth wireless technology, Bluetooth, which is also discussed below.

An Ethernet Refresher
As a touch-stone for the discussion of the capabilities of wireless technologies, a quick review of Ethernet would be helpful. It has been around for about 30 years and requires a cable connection. Ethernet hardware is now available from hundreds manufactures, and is now included on most new PCs and laptops. It is suitable for large or small networks, and you can get up to 300 feet from a hub or router. It has a theoretical throughput of 100 Mbps, and an actual of around 60Mbps (for Fast Ethernet). Odds are your office computer is plugged into an Ethernet network, and if you have a network at home, likely your home computer as well.

802.11b
The first IEEE approved standard was 802.11b ("eight-oh-two-eleven-bee"), also know as Wi-Fi. "B" devices were first available in late 1999. They are available from dozens of manufacturers, and are relatively inexpensive, $50-$150 for an AP, and $20-$75 for a PC Card. "B" devices operate in the 2.4GHz radio spectrum. This frequency range is also used by cordless phones, Bluetooth devices, and security radios, which makes Wi-Fi vulnerable to interference. At a range of 100 feet actual throughput for "B" devices is about 5.5Mbps. These data speeds are inadequate for transferring high-end multimedia content.

Being the first approved standard, as well as the cheapest option by far, have made "B" devices the most widely used in both work and home settings.

802.11a
802.11a was the next wireless standard approved by the IEEE. "A" devices were first available in late 2001. Don't be confused by the fact that the "A" standard comes after the "B" standard. The IEEE commenced work on the "A" standard first. Work on the "B" standard started next, and ultimately the "B" standard was approved first.

"A" has a couple of advantages over Wi-Fi. Actual throughput for "A" devices is a must faster 22 Mbps. This higher bandwidth makes them more suitable in situations where you have multiple users, have to transfer large files, or when the ability to stream multimedia content is required. "A" runs in a less used frequency range (5.15GHz to 5.35GHz) and, thus, is less prone to interference. "A" devices are available from a fewer number of manufacturers, and are slightly more expensive that "B" devices, approximately $120 for an AP, and $100 for a PC Card.

The "A" standard's main drawback is its shorter range: 50 feet compared to Wi-Fi's 100 feet. Note that Wi-Fi and 802.11a devices are not compatible as they use different radio frequencies. It works best in situations where you have a large number of users in close proximity who require high volumes connections

802.11g
The third wireless standard approved by the IEEE is 802.11g. "G" devices began shipping in mid-2003. "G" devices have the same faster throughput of "A" devices, and the longer range of "B" devices. "G" devices are more expensive than both "B" and "A" devices, typically $120-$200 for an AP, and $75-$125 for a wireless PC Card.

As "G" devices operate in the same frequency range that "B" devices, they are interoperable. Thus a laptop with a "B" wireless card can connect to a "G" AP. Note however, that when "G" devices share a network with "B" devices, the "G" devices may operate at the lower throughput of "B" devices.

There are also devices that will work in both "A" and "G" environments, but you pay a premium for them, $300 plus for an AP, and approximately $120 for a wireless PC Card.

Making a Choice
Devices that operate in both "A" and "G" let you function in both of these environments, but you pay a premium for this ability. If you are going with a single standard, go with "G". This will cost a bit more, but will give you maximum flexibility, and a likelihood of having a broad choice for other wireless options over the next several years. If you have a high volume of users that need high connection rates in a tight space, the "A" standard is the way to go. If budget is a concern, or you just want to try wireless out, "B" is the option for you.

Bluetooth
Bluetooth is the fourth wireless option you should know about. Any devices with a Bluetooth radio and antennae can speak to each other with little or no preparation. Bluetooth will soon be standard equipment on many cell phones, PDAs, and handheld or laptop computers. It is very inexpensive to incorporate Bluetooth into these devices.

Bluetooth is intended to be used in circumstances where you would want short-range temporary networking. For example, for transferring files between laptops at a meeting, printing a document to a local printer, accessing the Web at a coffee shop. In many ways Bluetooth is really a step-up from using infrared ports. It has no line-of-sight requirement and has a much longer range than infrared ports. Actual throughput for Bluetooth is about 300Kbps. Its range is between 20 and 40 feet, much further then infrared, but shorter than the 802.11 standards.

Bluetooth is great when you need easy and instant wireless connectivity as it doesn't require adapters, routers, gateways, access points etc. to connect to another device. Current users of Bluetooth find compatibility issues from both a hardware and software point of view. However, over time these issues will be resolved and Bluetooth will be used in more circumstances where easy ad-hoc wireless connectivity is required.

Turning On Security is a Must
Installing and configuring wireless technology used to be a nightmare. Today many products will work after simply plugging them in. One of many ways manufacturers have simplified set-up and installation is by turning off all security options. While this makes set-up easier, it is fraught with grave dangers from a security point of view. If you take anything away from this article, remember this point: you must take steps to increase the security settings on your wireless devices. If you don't do so, it is the equivalent of leaving the front door of your home or office wide open and unlocked. Anyone who can pickup your AP signal could potentially access your internet connection and data. It is for this same reason that IS departments are so afraid of employees installing an AP without permission on a corporate network.

For a more detailed review of the steps you must take to properly secure your wireless network, see the article The Sudduction of Wireless Networking: Resist the Temptation by Jeff Flax.

Looking to the Future
The wireless revolution is marching on all around us. There are several more standards in the works. 802.11i will plug some of the security holes in current standards. A new version of Bluetooth will operate at a higher frequency, which will double its present bandwidth. It you aren't wireless already, you likely will be soon. Originally wireless was touted as the ideal way to eliminate all those confusing wires and cables one has to deal with when connecting computers to networks, printers etc. This benefit is minor when compared with the ability to seamlessly access e-mail and the Web from just about anywhere. Get ready and jump on board join the wireless revolution.