what is a WLAN (Wireless Local Area Network)?

So you're ready to build a wireless LAN in your home? 

So you're ready to build a wireless LAN in your home? Not sure where to begin? I think I can help out a little.

First off, what is a WLAN (Wireless Local Area Network)?

Its a group of networked devices in close physical proximity of each other connected by means of wireless communications.

Wi-Fi is a marketing term used to describe products that conform to the 802.11 wireless communications standard. Most 802.11 wireless networking equipment that can be purchased on the market today will be Wi-Fi certified.

The three popular wireless standards today are 802.11a, 802.11b, and 802.11g. 802.11a is typically more expensive and used primarily in the business world.

802.11a

802.11a runs on a higher frequency than 802.11b and that makes the range a little shorter and more difficult for the signals to penetrate walls and other obstacles. 802.11a runs up to 54 Mbps in speed and signals in a regulated 5 GHz range.

802.11b

802.11b is more suitable for home networks because the range is greater than 802.11a and the signals are less easily obstructed but only runs at speeds around 11 Mbps.

802.11g

802.11g is the newer standard that combines some of the attributes of both 802.11a and 802.11b. 802.11g supports speeds up to 54 Mbps but unlike 802.11a it uses the 2.4 GHz frequency for greater range more like 802.11b. Unfortunately, lots of household appliances also use this range making signal interference more common on this unregulated signal frequency. 802.11g has backward compatibility with 802.11b such that an 802.11g wireless router or access point would allow connections from 802.11b devices as well as 802.11g devices.

Now, what's all this mean to you?

When selecting a base device (wireless router or access point) for your home network you will want to find something that is Wi-Fi certified and based on either the 802.11b or 802.11g standard. Depending on the speed you require and the amount of money that you want to spend.


One of the most common questions about wireless networking has to do with security. Out of the box, a wireless network is very un-secure. Now transactions you might have online with the bank or when purchasing items at an online store with your credit card would still be secured (most times) by the institution's website by means of SSL (Secure Socket Layer) encryption. However, e-mail, instant messages, and other similar communications are sent in clear text by default and would be easily readable by someone close enough to connect to an unsecured WLAN.

When WLANs began to gain popularity a few years ago wardriving became a common practice by some techies. This is the practice of driving or walking around with wireless networking equipment and snooping the wireless traffic in the neighborhood. Often times this would lead to the theft of computer resources like internet access from unsuspecting people with unsecured wireless networks. Various methods of wireless security protocols like WEP were introduced in order to mathematically encrypt or scramble the traffic making it unreadable by a human. WEP is still vulnerable by a skilled network cracker by running programs like airsnort to break the encryption keys but this takes lots of time and traffic and would not be very likely in a home networking environment.

There are several pieces of equipment related to a WLAN:

Wireless Network Adapters

A Wireless Network Adapter is a device that has a built-in radio transmitter and receiver (transceiver). They are also referred to as a NIC or Network Interface Card. Commonly they come as PCI or USB type adapters for desktop type devices or as a PCMCIA type of card for laptop computers. Many laptop computers today have embedded Wi-Fi chips inside of them allowing the computer to connect to wireless networks without the need for an extra component. A Wireless Network Adapter is a critical component to any wireless network as you will need it to connect your end devices (desktop computer, laptop, server, printer, etc) to your WLAN.

Wireless Access Points

A Wireless Access Point is a device that allows centralized communication between multiple wireless devices. Often referred to as a "base station" an access point can be used in wireless networks where there is already a pre-existing broadband router for Internet access, to connect multiple wired LANs or on wireless-only LAN without an exit point.

Wireless Routers

A Wireless Router is also a device that allows centralized communication but also allows for Internet connection sharing and often times firewall protection as well.

That covers the basics of WLAN protocols and equipment. Most network equipment configures differently so it's tough to do any type of overview without targeting specific equipment so in my next article I will cover configuring and securing a Linksys WLAN.