Computer Networks: efficiency - Gate 2018 mock set 2

Question

Which of the following statement is False about the efficiency of the given channel ?

A	If we want to send big packets on the channel, then Stop and Wait is good choice.
B	If length of packet increases, efficiency of channel also increases.
C	Distance between sender and receiver is directly proportional to efficiency of channel.
D	Efficient might be less if capacity of channel is high

Answer 1

option (c) is incorrect

explanation:-

option(A) -we know that in case of stop and wait ,efficiency =1/(1+2a) where a=PT/TT =>a=(d/v)*(B/L) where d is distance, v is propagation speed ,B is bandwidth and L is data length

here on putting values ,efficiency= 1/(1+2*d/v*B/L) ,we can say clearly when L increases efficiency also increases hence option A is correct.

option (B)-same as option A so true

option (C)-from the expression we can say directly that efficiency and distance is inversely proportional =>c is incorrect

option (D)-capacity of channel in case of stop and wait=B*PT so from the expression we can say if capacity increases then efficiency decreases. =>option D is correct