价格便宜的便携式计算机、移动电话和手持式设备的日趋流行，以及Internet应用程序和电子商务的快速发展，使用户需要随时进行网络连接。为满足这些需求，可以使用两种方法将便携式设备连接到网络，而没有电缆所带来的不便。这两种标准就是802.11b和Bluetooth。802.11b是一种11Mb/s 无线标准，可为笔记本电脑或桌面电脑用户提供完全的网络服务。
以往，无线局域网发展缓慢，推广应用困难，主要是由于传输速率低、成本高、产品系列有限，且很多产品不能相互兼容。如以前无线局域网的速率只有1～2Mb/s，而许多应用也是根据10Mb/s以太网速率设计的，限制了无线产品的应用种类。针对目前高速增长的数据业务和多媒体业务，无线局域网取得进展的关键就在于高速新标准的制定，以及基于该标准的10Mb/s甚至更高速率产品的出现。IEEE 802.11b从根本上改变了无线局域网的设计和应用现状，满足了人们在一定区域内实现不间断移动办公的需求，为我们创造了一个自由的空间。
Contents
3.8 Basic service set (BSS) basic rate set..........................................................................................1
4. Abbreviations and acronyms................................................................................................................2
7.2.3.1 Beacon frame format................................................................................................................2
7.2.3.9 Probe Response frame format..................................................................................................3
7.3.1.4 Capability Information field....................................................................................................3
7.3.1.9 Status Code field......................................................................................................................5
7.3.2.2 Supported Rates element..........................................................................................................5
9.2 DCF..............................................................................................................................................5
9.6 Multirate support..........................................................................................................................6
10.3.2.2 MLME_scan.confirm.............................................................................................................6
10.3.2.2.2 Semantics of the service primitive......................................................................................7
10.3.3.1.2 Semantics of the service primitive......................................................................................8
10.3.10 Start.........................................................................................................................................8
10.3.10.1.2 Semantics of the service primitive....................................................................................9
10.4.4 PLME_DSSSTESTMODE.....................................................................................................10
18. High Rate, direct sequence spread spectrum PHY specification.......................................................11
18.1Overview....................................................................................................................................11
18.2High Rate PLCP sublayer..........................................................................................................12
18.3High Rate PLME........................................................................................................................27
18.4High Rate PMD sublayer...........................................................................................................30
Annex A (normative), Protocol implementation conformance statement (PICS) proforma.........................59
Annex C (normative), Formal description of MAC operation......................................................................64
Annex D (normative), ASN.1 encoding of the MAC and PHY MIB............................................................88
Annex F (informative), High Rate PHY/frequency-hopping interoperability...............................................89
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