Wireless communication protocols have evolved rapidly since the introduction of 802.11 Legacy over a decade ago. Over the last 10 years we have seen efficiency and performance increases on all fronts, which have lead to greater range and faster transfer speeds.
With Legacy 802.11 protocols, speeds maxed out at around 2 Mbits/sec and indoor range was only about 20 meters. In 1999, the 802.11 protocol got a couple of amendments in the form of 802.11a and 802.11b. Both offered higher speeds and slightly greater range, but there were many differences between the two standards in how they achieved those two things. 802.11b uses an offshoot of the same modulation technique as the older Legacy protocol, known as complementary code keying (CCK) (based on direct-sequence spread spectrum used in Legacy). Both protocols also use CSMA/CA for multiple access, which is the reason both Legacy and 802.11b protocols were much slower than any of the other versions we’ve seen – CSMA/CA carries a......
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