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It’s no surprise that the IEEE 802.11x wireless-local-area-network (WLAN) standards are commonly referred to as "alphabet soup." With over 35 lettered standards ranging from IEEE 802.11a to 802.11ak—each differentiated by only a few letters—it’s easy to be left perplexed by the nomenclature. The relative traffic of WLAN networks is increasing with new frequency bands, throughput rates, data streams, the proliferation of personal electronic devices, and industrial/commercial uses. Standards range from general maintenance to a China millimeter-wave standard. The key thing to understand is that the IEEE 802.11 Working Group of the IEEE Standards Association is dealing with a rapidly growing, expanding, and evolving wireless world with new demands and technological breakthroughs. To keep up with this fast-paced evolution, the working group convenes regularly to generate improvements, updates, and even forecast the future of WLAN.


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Several standards designations are left out to limit confusion, amended out of the general pool of standards, or limited to recommendations (as opposed to official standards). To reduce confusion, the working group decided to not label any standard or task group with an ending of l, o, q, x, ab, or ag. The designations F and T were either withdrawn or cancelled, respectively, and remain merely as recommended practices.

The original standard, IEEE 802.11-1997, only supported one stream of 1 to 2 Mb/s throughput at 2.4 GHz with approximate indoor range of 20 m and outdoor range of 100 m. It has since been supplanted by the IEEE 802.11-2007 amendments, which brought together the standard designations a, b, d, e, g, h, i, and j. In the summer of 2007, those amendments were finalized by REVma or IEEE 802.11ma, which was developed by the maintenance task group TGma.

The amendment release IEEE 802.11-2007 was then made obsolete by the IEEE 802.11-2012, which was finalized by task group TGmb as REVmb or IEEE 802.11mb. This revision brought together the k, r, y, n, w, p, z, v, u, and s standards. Beyond these standards, there are many that are assigned to maintenance, specific applications, industrial/commercial, government, security, and data-communication protocols. (See “Uncommon Letters In Your Soup Bowl.”)

Currently Used And Updated Standards

Of course, then there are the commonly used and frequently updated standards, such as IEEE 802.11a, b, g, and n. IEEE 802.11a has undergone many transformations, extensions, and additions since 1999—including gaining the functionality added by standards h and y. The IEEE 802.11a standard, which uses orthogonal frequency division multiplexing (OFDM), has 20-MHz bandwidths in the 5.0- and 3.7-GHz bands. It allows for data rates from 1.5 to 54.0 Mb/s at ranges of 35 m (indoors) to 120 m (outdoors) with a single data stream. The 3.70-GHz enhancement increased the power limits of 802.11a in that band, increasing the outdoor wireless range to 5000 m in the US.

IEEE 802.11b—the most commonly used WLAN standard in the 2.4-GHz band—has been available to market products since 2000. IEEE 802.11b has 20-MHz bandwidth with a single data stream. It operates from 1 to 11 Mb/s and has an indoor range of 35 m and an outdoor range of 140 m. IEEE 802.11b uses the Direct Sequence Spread Spectrum (DSSS) modulation technique. It commonly suffers from interference from other commonly used wireless devices, such as microwaves, baby monitors, Bluetooth devices, cordless telephones, and amateur-radio equipment.

IEEE 802.11g, which is an updated version of 802.11b, arrived in 2003. It operates in the same 2.4-GHz frequency band. By using the same OFDM modulation technique as 802.11a, however, it increases data rates to 54 Mb/s. IEEE 802.11g devices offer only a single data stream. They have an indoor range of 38 m and an outdoor range of 140 m. The devices suffer from the same interference problems as those using IEEE 802.11b. They also face an additional problem, as 802.11b devices cause a decrease in data rates for 802.11g devices.

Added in 2009, IEEE 802.11n is an amendment to the standards that as multiple-input multiple-output (MIMO) antennas. It increases data rates over multiple channels using both a 20-MHz band within the 2.4-GHz band and a 40-MHz band within the 5.0-GHz band. The 2.4-GHz operations of 802.11n data rates range from 7.2 to 72.2 Mb/s while the 5.0-GHz data rates, individually, are 15 to 150 Mb/s. The range of 802.11n devices can use up to four data streams with ranges of 70 m indoors and 250 m outdoors using OFDM modulation. 

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What's New On Shelves

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In 2012, ABI Research predicted that the number of Wi-Fi devices shipped in 2012 would exceed 1.5 billion. That is only one market among many, including military, accounted for in the IEEE 802.11 standards. New standards—IEEE 802.11ac, af, ah, a, mc, aj, aq, and ak—are being developed with much higher data rates, streams, range, and more robust modulation methods. They are given the ability to reuse open white-space bands, enhance old standards, provide more maintenance channels, and otherwise prepare for the future. Here is a rundown of those newer standards:

IEEE 802.11ac, which will be formally added in 2014, operates in the 5-GHz bands with a 160-MHz bandwidth and eight data streams, thereby allowing data rates per stream to 1 Gb/s. It is predicted that the high-density modulation method of 256 quadrature amplitude modulation (256QAM) will be used with this standard to enhance the data rates per stream and operate with similar ranges to 802.11n.

IEEE 802.11ad, or WiGig, is a published standard that is being rushed to market in 2014 using the new 60-GHz band with theoretical maximums of 7 Gb/s per data stream. Due to the small wavelengths at 60 GHz, the range of 802.11ad devices will only exceed 10 m, with poor wall penetration. The goal is to use 802.11ad, 802.11ac, and 802.11n in a triband technology for the 2.4-, 5.0-, and 60.0-GHz bands. This approach will allow manufacturers to take advantage of all of the strengths of each standard while mitigating the negatives. Going forward, also keep an eye out for these standards:

IEEE 802.11af is the TV white space standard to be added in 2014.

IEEE 802.11ah is a sub-1-GHz sensor-network standard slated for 2016. It targets smart metering, where there are large groups of stations that share the band while minimizing energy consumption.

IEEE 802.11ai is a WLAN study group with the goal of standardizing fast initiallink-setup functions by 2015. It will enable WLAN clients to connect with a secure link setup within 100 ms.

IEEE 802.11mc will be the new maintenance standard in 2015.

IEEE 802.11aj is slated for China millimeter-wave use in 2016.

IEEE 802.11aq is a task group expected to develop an amendment that defines modifications to the 802.11 standards, enabling the delivery of pre-association service discovery information by stations by 2015.

IEEE 802.11ak is a task group created to explore the use of links as connections within bridged networks. This approach could increase the utility of connections between access points by removing limitations to in-traffic bridged networks.

Additional Resources

Official IEEE 802.11 Working Group Project Timelines.

Official IEEE 802.11 Wireless LAN Standards.

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Uncommon Letters In Your Soup Bowl

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Among the 35 and growing IEEE 802.11 standards are a host of standards devoted to maintenance, expansion, corrections, enhanced functionality, internationally interoperability, and security enhancement.  Listed below are the current standards that only the most knowledgeable wireless buffs would know about:

IEEE 802.11c: This standard, which was added in 2001 to bridge operational procedures, also is included in the IEEE 802.1D standard.

IEEE 802.11d: Added in 2001 as the international roaming-extensions standard, it allows wireless access points and client devices to conform to the regulations enforced in various countries.

IEEE 802.11e: This quality-of-service (QoS) enhancement was added in 2005 through modifications to the media-access-control (MAC) layer, benefiting time-delay-sensitive applications like voice-over-wireless-LAN and multimedia streaming

IEEE 802.11h: This standard was added in 2004 as a spectrum-managed, European-compatible version of IEEE 802.11a with throughput to 5 GHz. It provides dynamic-frequency-selection (DFS) and transmit-power-control (TPC) regulations, which solve interference problems with satellites and radar using the 5-GHz bands.

IEEE 802.11i: This enhanced security standard was implemented as Wireless Protected Access Two (WPA2) in 2004. It replaced the original clause with a detailed “security” clause and deprecated Wireless Equivalent Privacy (WEP).

IEEE 802.11j: This standard extension was added in 2004 to aid conformance with Japanese rules for indoor/outdoor applications, mobile applications, and radio applications in the 4.9-to-5.0-GHz bands.

IEEE 802.11k: The IEEE 802.11k standard was added in 2008 as an enhancement for radio resource management and mobile-WLAN maintenance.

IEEE 802.11p: In 2010, IEEE 802.11p was added as the Wireless Access for the Vehicular Environment standard. It supports Intelligent Transportation Systems (ITS) applications including data exchange between high-speed vehicles and roadside infrastructure. IEEE 802.11p is licensed in the 5.850-to-5.925-GHz ITS band.

IEEE 802.11r: The fast BSS transition (FT) amendment, which dates back to 2008, permits fast and secure handoffs between base stations for continuous connectivity with wireless devices in motion.

IEEE 802.11s: This standard was added in 2011 to account for mesh networking and extended service set (ESS) for static topologies and ad-hoc networks when creating WLAN mesh networks.

IEEE 802.11u: To aid the offloading of cellular networks, this 2011 standard provides improvements related to hot spots, third-party client authorization, and commercial establishments.


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IEEE 802.11v: IEEE 802.11v was added in 2011 to allow the configuration of client devices while connected to wireless networks as a method of wireless network management.

IEEE 802.11w: To increase security, this 2009 standard provides management frames that are confidential. (Management frames are controls that enable data integrity, data origin authenticity, and replay protection.)

IEEE 802.11y: Added in 2008, this standard enables high-power data-transfer equipment in the US 3650-to-3700-MHz band to operate using the 802.11a standard.

IEEE 802.11z: This 2010 standard extends the Direct Link Setup (DLS) protocol, thereby allowing for a direct link between WLAN devices after accessing a wireless network, such as tunneled DLS (TDLS).

IEEE 802.11aa: This standard, which was added in 2012, includes enhancements to the robust, reliable, and fast transfer of video-streaming information over WLAN networks.

IEEE 802.11ae: In 2012, 802.11ae was added to amend the capability to prioritize management frames.

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