Wireless Ethernet is IEEE 802.11b today, the IEEE standard
for wireless LAN’s. IEEE 802.11b operates in the ISM band at
11 Mbps. However, several new versions of the standard is
being developed, 802.11a, which supports data rates of up to
54 Mbps, and operates in the 5-GHz UNII (Unlicensed
National Information Infrastructure) band. Another version
802.11g is currently being developed which will support up to
20+ Mbps. Table 2-1 summarizes the different versions of
802.11 and includes HiperLAN2 for comparison. It should
also be noted that the IEEE is working on 802.11e, a standard
that spans home and business environments with QoS and
multimedia support while maintaining full backward compatibility
with 802.11b and 802.11a. This version will support
voice and include a higher level of security than 802.11b. The
release date for the standard is unclear at this time.
The IEEE802.11b specification was finalized in 1999 and
quickly adopted by many companies. However, it was just as
quickly discovered that there are two problems: the security is
weak and the theoretical transmission speeds of 11 Mbps falls
short—real world speed is only about 7 Mbps.