Wireless LAN

wireless_network.jpg

WI-FI_Range_Diagram.svg

WLAN_PCI_Card_cleaned.png

Wlan_adhoc.png

Wifi_hidden_station_problem.svg

Roaming01.svg

Wireless LAN (WLAN) is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building. This gives users the ability to move around within the area and still be connected to the network.

Overview

A WLAN typically extends an existing wired local area network. WLANs are built by attaching a device called an access point (AP) to the edge of the wired network. Clients communicate with the AP using a wireless network adapter similar to an Ethernet adapter. The standard for WLANs is IEEE 802.11, which is commonly known as Wi-Fi.

History

The first wireless LAN was developed in 1971 at the University of Hawaii under the name ALOHAnet. The technology has since evolved significantly, with the introduction of the IEEE 802.11 standard in 1997, which has undergone several amendments to improve speed, security, and reliability.

Components

A typical WLAN consists of the following components:

• Access point (AP): A device that allows wireless devices to connect to a wired network using Wi-Fi.
• Wireless network interface controller (WNIC): A hardware device that connects a computer to a wireless network.
• Router: A device that forwards data packets between computer networks, creating an overlay internetwork.

Standards

The most common WLAN standard is IEEE 802.11, which includes several variations:

• IEEE 802.11a: Operates in the 5 GHz band and provides up to 54 Mbps.
• IEEE 802.11b: Operates in the 2.4 GHz band and provides up to 11 Mbps.
• IEEE 802.11g: Operates in the 2.4 GHz band and provides up to 54 Mbps.
• IEEE 802.11n: Operates in both 2.4 GHz and 5 GHz bands and provides up to 600 Mbps.
• IEEE 802.11ac: Operates in the 5 GHz band and provides up to several Gbps.

Security

WLANs are susceptible to various security threats, including eavesdropping, denial-of-service attacks, and man-in-the-middle attacks. To mitigate these risks, several security protocols have been developed:

• Wired Equivalent Privacy (WEP): An older security protocol that is now considered insecure.
• Wi-Fi Protected Access (WPA): An improved security protocol that addresses many of WEP's weaknesses.
• Wi-Fi Protected Access II (WPA2): A more secure version of WPA that uses Advanced Encryption Standard (AES).

Applications

WLANs are used in various applications, including:

• Home networks: Allowing multiple devices to connect to the internet and share resources.
• Enterprise networks: Providing wireless connectivity in office environments.
• Public hotspots: Offering internet access in public places such as cafes, airports, and libraries.

Related Pages

• Wi-Fi
• IEEE 802.11
• Access point
• Router
• Wireless network interface controller
• Network security

Categories

   This article is a  stub. You can help WikiMD by expanding it!