Wi-Fi is a term for certain types of wireless local area networks (WLAN) that use specifications in the 802.11 family. Products that pass the Wi-Fi Alliance tests for interoperability, security and application-specific protocols are labeled "Wi-Fi CERTIFIED," a registered trademark of the Alliance.
Wi-Fi is widely used in businesses, agencies, schools, and homes as an alternative to a wired LAN. Many airports, hotels, and fast-food facilities offer public access to Wi-Fi networks. These locations are known as hot spots. Many charge a daily or hourly rate for access, but some are free. An interconnected area of hot spots and network access points is known as a hot zone.
Unless adequately protected, a Wi-Fi network can be susceptible to access by unauthorized users who use the access as a free Internet connection. The activity of locating and exploiting security-exposed wireless LANs is called war driving. An identifying iconography, called war chalking, has evolved. Any entity that has a wireless LAN should use security safeguards such as the Wired Equivalent Privacy (WEP) encryption standard, the more recent Wi-Fi Protected Access (WPA), Internet Protocol Security (IPsec), or a virtual private network (VPN).
The term Wi-Fi was created the Wi-Fi Alliance as a play on "Hi-Fi," an abbreviation for "high fidelity," which referred to high-quality audio reproduction. Similarly, Wi-Fi is often thought to be short for wireless fidelity. However, according to the Wi-Fi Alliance, "Wi-Fi" is not an abbreviation. The confusion may stem from the fact that the Alliance briefly used "The standard for wireless fidelity" as a slogan for Wi-Fi.
Originally, Wi-Fi certification was applicable only to products using the 802.11b standard. Today, Wi-Fi can apply to products that use any 802.11 standard. The 802.11 specifications are part of an evolving set of wireless network standards known as the 802.11 family. The particular specification under which a Wi-Fi network operates is called the "flavor" of the network.
|802||Overview||Basics of physical and logical networking concepts.|
|802.1||Bridging||LAN/MAN bridging and management. Covers management and the lower sub-layers of OSI Layer 2, including MAC-based bridging (Media Access Control), virtual LANs and port-based access control.|
|802.2||Logical Link||Commonly referred to as the LLC or Logical Link Control specification. The LLC is the top sub-layer in the data-link layer, OSI Layer 2. Interfaces with the network Layer 3.|
|802.3||Ethernet||"Grandaddy" of the 802 specifications. Provides asynchronous networking using "carrier sense, multiple access with collision detect" (CSMA/CD) over coax, twisted-pair copper, and fiber media. Current speeds range from 10 Mbps to 10 Gbps. Click for a list of the "hot" 802.3 technologies.|
|802.5||Token Ring||The original token-passing standard for twisted-pair, shielded copper cables. Supports copper and fiber cabling from 4 Mbps to 100 Mbps. Often called "IBM Token-Ring."|
|802.6||Distributed queue dual bus (DQDB)||"Superseded **Revision of 802.1D-1990 edition (ISO/IEC 10038). 802.1D incorporates P802.1p and P802.12e. It also incorporates and supersedes published standards 802.1j and 802.6k. Superseded by 802.1D-2004." (See IEEE status page.)|
|802.7||Broadband LAN Practices||Withdrawn Standard. Withdrawn Date: Feb 07, 2003. No longer endorsed by the IEEE. (See IEEE status page.)|
|802.8||Fiber Optic Practices||Withdrawn PAR. Standards project no longer endorsed by the IEEE. (See IEEE status page.)|
|802.9||Integrated Services LAN||Withdrawn PAR. Standards project no longer endorsed by the IEEE. (See IEEE status page.)|
|802.10||Interoperable LAN security||Superseded **Contains: IEEE Std 802.10b-1992. (See IEEE status page.)|
|802.11||Wi-Fi||Wireless LAN Media Access Control and Physical Layer specification. 802.11a,b,g,etc. are amendments to the original 802.11 standard. Products that implement 802.11 standards must pass tests and are referred to as "Wi-Fi certified."|
|802.12||Demand Priority||Increases Ethernet data rate to 100 Mbps by controlling media utilization.|
|802.13||Not used||Not used|
|802.14||Cable modems||Withdrawn PAR. Standards project no longer endorsed by the IEEE.|
|802.15||Wireless Personal Area Networks||Communications specification that was approved in early 2002 by the IEEE for wireless personal area networks (WPANs).|
|802.15.1||Bluetooth||Short range (10m) wireless technology for cordless mouse, keyboard, and hands-free headset at 2.4 GHz.|
|802.15.3a||UWB||Short range, high-bandwidth "ultra wideband" link|
|802.15.4||ZigBee||Short range wireless sensor networks|
|802.16||Wireless Metropolitan Area Networks||This family of standards covers Fixed and Mobile Broadband Wireless Access methods used to create Wireless Metropolitan Area Networks (WMANs.) Connects Base Stations to the Internet using OFDM in unlicensed (900 MHz, 2.4, 5.8 GHz) or licensed (700 MHz, 2.5 – 3.6 GHz) frequency bands. Products that implement 802.16 standards can undergo WiMAX certification testing.|
|802.17||Resilient Packet Ring||IEEE working group description|
|802.18||Radio Regulatory TAG||IEEE 802.18 standards committee|
|802.19||Coexistence||IEEE 802.19 Coexistence Technical Advisory Group|
|802.20||Mobile Broadband Wireless Access||IEEE 802.20 mission and project scope|
|802.21||Media Independent Handoff||IEEE 802.21 mission and project scope|
|802.22||Wireless Regional Area Network||IEEE 802.22 mission and project scope|