a. Distinguish between physical links and data links. b. What advantage of optical fibre over UTP was listed in the text? c. Why is spread-spectrum transmission used in wireless LANs? d. Why are...

a. Distinguish between physical links and data links. b. What advantage of optical fibre over UTP was listed in the text? c. Why is spread-spectrum transmission used in wireless LANs? d. Why are switch supervisory frames needed? e. Why does optical fibre have better inherent security than UTP? f. What dangers does radio transmission create? g. Does spread-spectrum transmission in commercial wireless LANs provide security? h. Why is the 802.1AE standard necessary?