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Let transmission time  = 1ms , propagation delay = 1 ms and we have used TDM access control method.

What is the efficiency of the network and what is throughput if we are given a bandwidth of 4mbps.

If we want to have N number of nodes/stations in this network and each requires 2kbps of bandwidth. Then what is the value of N ?
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efficiency = 50%

throughput = 2mbps

# stations=1000... ????
efficiency is correct but i am confused with # of stations.

Should we use effective Bandwidth( 2mbps) or given bandwidth( 4 mbps) to find number of stations.

Why should we use 2mbps in calculation and why not 4mbps?

TDM is one of simplest method for access control. In TDM a fixed time slot is allocated to all node in round robin manner.

so efficiency in TDM = Tt/(Tt+Tp) where Tt is Transmission delay and Tp is Propagation delay

efficiency n = 1/(1+1) = 0.5 %

so throughput / link utilization = 0.5 * bandwidth = 0.5 * 4 = 2 mbps  (i.e. only 2 mbps out of 4 mbps is utilized for channel )

if one station require 2kbps then maximum ( 2mbps/2kbps) = 1000 stations can be there in the link.
answered by (237 points) 1 2 8
efficiency = 50%

throughput=2

N=1000
answered by (121 points) 2

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