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18.2. The Standards
The standards based around wireless
networking for PCs are established by the Institute of Electrical and
Electronics Engineers (IEEE). LAN/MAN technology has been broadly
assigned number 802, which is then broken down into working groups.
Some of the most active wireless working groups include 802.15,
designed for wireless personal area networks (Bluetooth), 802.16
which defines support for broadband wireless systems, and finally,
802.11, assigned to wireless LAN technology. Within the 802.11
definition, there are more specific definitions that are assigned
letters. Here is a list of the most important 802.11 wireless LAN
definitions:802.11a
This definition provides wireless access on the 5 GHz band. It offers
speeds of up to 54 MBps, but has not caught on, perhaps due to
relatively higher priced equipment and short range.
802.11b
This is still the standard to which most people refer when talking
about wireless networking. It establishes 11 MBps speeds on the 2.4
GHz band, and can have a range extending more than 500 meters.
802.11g
This standard has been established to
provide higher data rates within the 2.4 GHz band and provides added
security with the introduction of WiFi Protected Access, or WPA.
802.11g devices are now being deployed in place of 802.11b devices
and have nearly reached mainstream acceptance.
802.11i
While still in the development phase, this
standard seeks to resolve many of the security issues that have
plagued 802.11b and provide a more robust system of authentication
and encryption. At the time of this writing, the specification has
not been finalized.
802.11n
802.11n is being touted as the high-speed answer to current wireless
network speed shortcomings. With an operational speed of 100 Mbps, it
will roughly double existing wireless transfer speeds, while
maintaining backward compatibility with b and g. At the time of this
writing, the specification is not complete; however, several vendors
have released "pre-n" products,
based on the early drafts of the specification.
