802.11b
Very anon afterwards acceptance of the 802.11b standard, 802.11b admission credibility and radio cards
began shipping. It was a adequately accessible modification to absolute 802.11 DSSS accessories to become
802.11b-compliant. In fact, best users could advancement their absolute admission credibility and radio
cards with simple firmware upgrades. For several years, 802.11b accessories were the best ones
on the market, so they proliferated throughout the industry and became the best commonly
installed wireless LAN hardware.
An advantage of 802.11b, then, is that it interoperates able-bodied with the majority of installed
wireless LANs. That is why best wireless user accessories accommodate 802.11b. It is not compatible
with 802.11a, but 802.11b does interface with 802.11g systems.
Much added RF interference, however, resides in the 2.4-GHz band, which impacts 802.11b users.
As mentioned before, a bake oven can account cogent abasement in throughput because
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Appendix G: IEEE 802.11 Fundamentals
radio after-effects from a bake oven can block 802.11b and 802.11g radio cards from accessing
the average or actualize bit errors in the 802.11 frames in transit. The abeyant for RF interference
in the 2.4-GHz bandage is one acumen why a aggregation should acerb accede application 802.11a
solutions.
A attached agency of 802.11b is that it supports alone up to three nonoverlapping radio beef in the
same area. The 2.4-GHz abundance spectrum is almost 84-MHz wide, and an 802.11b radio card
or admission point uses about 30 MHz back transmitting. To abstain arrest among
access points, 802.11b admission credibility charge be set to specific channels. For example, admission points
in the United States can be set to channels 1, 6, and 11 to abstain overlap and alternate interference.
This is abnormally important if there are abounding alive wireless users. As a aftereffect of this frequency
plan and bound abstracts rates, 802.11b has bound capacity.