TELECOMMUNICATIONS SYSTEMS
COMMUNICATION WIRELESS COMPUTING DEVICES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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FHSS and DSSS
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THSS and FHSS
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THSS and DSSS
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Hybrid technique
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Detailed explanation-1: -Which of the following spread spectrum techniques were used in the original IEEE 802.11 standard? Explanation: Original IEEE 802.11 used both the approaches of FHSS (Frequency Hopping Spread Spectrum) and DSSS (Direct Sequence Spread Spectrum).
Detailed explanation-2: -IEEE 802.11 was the original version released in 1997. It provided 1 Mbps or 2 Mbps data rate in the 2.4 GHz band and used either frequency-hopping spread spectrum (FHSS) or direct-sequence spread spectrum (DSSS).
Detailed explanation-3: -IEEE 802.11 wireless LANs use a media access control protocol called Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA).
Detailed explanation-4: -IEEE 802.11 uses various frequencies including, but not limited to, 2.4 GHz, 5 GHz, 6 GHz, and 60 GHz frequency bands. Although IEEE 802.11 specifications list channels that might be used, the radio frequency spectrum availability allowed varies significantly by regulatory domain.
Detailed explanation-5: -802.11i-It is an IEEE 802.11 amendment used to facilitate secure end-to-end communication for wireless local area networks (WLAN). IEEE 80211i improves mechanisms for wireless authentication, encryption, key management and detailed security.