How Wireless Networking Works

Now that you have a feel for how computers and other devices talk on a network, we can take a look at how wireless networking actually works. Wireless network connections take advantage of radio signals and infrared light (these connections are limited in range). WiFi connections between WiFi-enabled computers and other WiFi devices such as wireless routers have a maximum range of around 300 feet.

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Other wireless and longer-distance communication strategies (such as those used by cell phones that take place through cellular telephone technology) can provide greater range. This is because a cell phone can connect to a cellular antenna that is miles away from the phone. Some Internet service providers (that also happen to be cellular phone companies) such as Verizon and even Google are looking at technology that offers a high-speed wireless network (which is being called WiFi but differs from the home WiFi we are discussing here). This cellular technology can be accessed from nearly anywhere in a geographic location (such as a city) and can also be used to access the Internet. So, the physically wired high-speed Internet connections we take advantage of through DSL and cable modems might be slowly replaced by this WiFi-on-steroids technology that is beginning to roll out in major metropolitan areas.

In terms of home and small office networking, the Ethernet WLAN hardware available takes advantage of radio connectivity. The equipment operates in the part of the frequency range that the FCC has reserved for unregulated use; you will find that wireless LANs operate in the 2.4GHz and higher ranges.

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Wireless networking equipment operates in the same frequency range as analog and digital home telephones and other devices.

The only difference between a (wired) Ethernet LAN and an Ethernet WLAN is that the WLAN sends data over radio waves rather than through network cables. A WLAN is still an Ethernet network, plain and simple. However, wireless Ethernet has its own set of standards that have been developed by the IEEE (the Institute of Electrical and Electronics Engineers, a worldwide standards organization). Let's take a look at the wireless Ethernet standards.

Understanding Wireless Networking Standards

The IEEE has created a set of standards for networking that fall under the IEEE 802 specifications (a series of engineering specifications for devices). The standard for wireless Ethernet is designated as 802.11. Three types of 802.11 standards are currently in use for wireless networking:

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The 802.11 wireless standards are also often referred to as WiFi. You will often see 802.11 hardware labeled as "WiFi devices." It's not a different wireless standard, just a nickname.

• 802.11a This 802.11 specification can provide up to 54Mbps of bandwidth and operates in the 5GHz band of the usable (public) radio spectrum. 802.11a is just starting to make its way into the home networking marketplace, and wireless equipment vendors such as Linksys have begun to roll out products using this specification. Oddly enough, WiFi 802.11b and 802.11g were available WiFi standards before 802.11a was implemented.

• 802.11b This specification provides up to 11Mbps of throughput and operates in the 2.4GHz band. 802.11b was the first wireless Ethernet specification available (in 1999). The speed of a computer connected to a 802.11b access point decreases the further the computer is from the access point. The 802.11b standard does not provide the type of range you get from 802.11g. A distance of 100 feet or more between the access point and the WiFi-enabled computer typically does not provide an adequate signal strength.

• 802.11g This specification provides bandwidth between 20 and 54Mbps in the 2.4GHz band. It is currently the fastest growing implementation of wireless networking for home networks and small LANs. This specification can provide good connections between access points and WiFi-enabled computers that are up to 300 feet apart.

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You probably wonder what the 802.11 numbering is all about in terms of the wireless Ethernet standards. The IEEE provides the specifications for all types of networking standards. For example, 802.3 is the specification for Ethernet LANs (meaning wired LANs).

In terms of cost, 802.11a devices are the most expensive and only a few vendors currently have 802.11a products available for home and small office networking. 802.11g products are certainly the most common and provide the most bandwidth in relation to cost. You really can't go wrong building your network with 802.11g devices.

802.11b products are starting to disappear from stores and you will find that most 802.11b hardware is on sale. If you can deal with the slower data rate that 802.11b provides, you can put together a wireless home network for practically a song. However, you certainly won't get the performance or range you can get from 802.11g devices.

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The 802.11 wireless standards aren't the only wireless standards out there. Another wireless standard is called Bluetooth. Bluetooth is gaining momentum in the cellular phone industry and is used for a variety of peripheral devices such as hands-free devices for cell phones. Toyota has even built Bluetooth into some of its vehicles such as the Prius, which allows you to sync your cell phone to your car's hands-free phone system. Bluetooth does not yet support TCP/IP data transfer, so for now, Bluetooth does not compete with the 802.11 standards.