Networking

Wireless LAN Overview

A simple home wireless LAN

This gallery is also available as a TechRepublic article.

Introduction

Wireless LANs based on the IEEE 802.11 standards allow wire- free networking in the local area network environment using the unlicensed 2.4 or 5.3 GHz unlicensed radio band. They're used everywhere from homes to Fortune 500 companies to hotspot Internet access. This article will offer a brief summary of the various network topologies in various environments.

In the most common and cheapest example of a home Wireless LAN, Above shows a single device acting as the Firewall, Router, Switch, and Wireless Access Point. These Wireless Routers can provide a wide range of functions such as:

  • Protects the home network from outside intruders
  • Allows the sharing of a single Internet IP address from an ISP (Internet Service Provider)
  • Provides Wired Ethernet service for typically 4 computers but can also be expanded with another Ethernet Switch or Hub
  • Serves as a Wireless Access Point for multiple wireless computers


These devices come from a variety of manufacturers such as Linksys (Cisco), D-Link, Netgear, SMC, Belkin, and other companies. Basic models can be purchased for as little as $30 and high-end models can be more than $150. The basic models typically have a single Wi-Fi radio offering 2.4 GHz 802.11b/g operation while the higher end models will offer dual-band Wi-Fi radios or high-speed MIMO capability. Dual-band Access Points have two radios which provide 2.4 GHz 802.11b/g and 5.3 GHz 802.11a capability while MIMO Access Points use multiple radios to boost performance in the 2.4 GHz range. Dual-band Access Points are essentially two Access Points in one and can serve two non-interfering frequencies at the same time while the newer MIMO devices boost speed in the 2.4 GHz range along with superior range. Unfortunately, the 2.4 GHz range is often congested and manufacturers have stayed away from dual-band MIMO devices because of cost concerns since they're already the most expensive to begin with. Dual-band devices don't have the highest performance or range, but allow you to operate in the relatively uncongested 5.3 GHz range and allow two devices to operate at full speed simultaneously if they are in different bands.

0 comments