PHYSICAL LAYER AND TRANSMISSION MEDIA
BANDWIDTH UTILIZATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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higher data rate
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infinite frames
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empty slots
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Both A and C
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Detailed explanation-1: -Synchronous TDM is not as efficient as it could be. If a source does not have data to send, the corresponding slot in the output frame is empty. The following figure shows a case in which one of the input lines has no data to send and one slot in another input line has discontinuous data.
Detailed explanation-2: -One solution to this problem is statistical TDM. Statistical TDM (sometimes called asynchronous TDM) transmits data only from active users and does not transmit empty time slots.
Detailed explanation-3: -Disadvantages of TDM are the entire system will fail if there exists one channel failure, it takes a lot of time to shift from one channel to another, more complex than other methods, it requires an expensive regenerative repeater to regenerate the signal.