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2.1 | |
802.11 Standards | |
| 2.1.2 | |
IEEE and 802.11 |
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Overview of IEEE and the 802 Committee The IEEE, founded in 1884, is a nonprofit professional organization comprised of over 377,000 members worldwide. The IEEE consists of many individual societies and working groups. It plays a critical role in developing standards, publishing technical works, sponsoring conferences, and providing accreditation in the area of electrical and electronics technology. In the area of networking, the IEEE has produced many widely used standards such as the 802.x group of local area network (LAN) and metropolitan area network (MAN) standards, which are listed in Figure  .
The IEEE 802 LAN/MAN Standards Committee (LMSC) develops local area network (LAN) and metropolitan area network (MAN) standards primarily for the lowest two layers of the Open Systems Interconnection (OSI) reference model. LMSC, or IEEE Project 802, coordinates with other national and international standards groups. Some standards initiated here are published by the ISO as international standards. Figure
As shown in Figure
IEEE 802.11 The 802.11 standard is officially called the IEEE Standard for WLAN MAC and PHY specifications. It defines the over the air protocols necessary to support wireless networking in a local area. The primary service of the 802.11 standard is to deliver MAC Service Data Units (MSDUs) between peer LLC devices at the data link layer. Typically, a radio card, or NIC, and one or more access points provide the functions of the 802.11 standard. The MAC and PHY characteristics for wireless local area networks (WLANs) are specified in the 802.11x standard. The MAC layer in this standard is designed to be able to support additional physical layer units as they are adopted, dependent on the availability of spectrum and new modulation techniques.
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shows the architecture defined by the 802 committee and how many
different media access methods are supported with this model. The
media access control (MAC) and the physical layers (PHY) are organized
into a separate set of standards from the logical link control (LLC).
This is because of interdependence between medium access control,
medium, and the topology of each standard. At the same time, a single
LLC process can support the logical functions for all underlying MAC
and PHY protocols. 
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the combination of the 802.2 LLC standard and any given MAC protocol
is functionally equivalent to the OSI data link layer. The MAC and LLC
processes are typically referred to as sublayers of the data link
layer.
. The 802.11 is a wireless standard which specifies
connectivity for fixed, portable, and moving stations within a local
area. The purpose of the standard is to provide wireless connectivity
to automate machinery and equipment or stations that require rapid
deployment. These may be portable, handheld, or mounted on moving
vehicles within a local area. 
