What is the total delay (latency) for a frame size of 10 million bits that is being set up on a link with 15 routers, each having a queuing time of 2 s and a processing time of 1 s? The length of link is 3000 km. The speed of light inside the link is 2 x 108 m/s. The link has bandwidth of 6 mbps.
Answers
Given data:
Distance (length of the link) =2000 Km
=2000103m
Propagation speed=2108m/s
Frame size=5million bits
=5000000bits
The Bandwidth=5Mbps
=5106 bps (1Mbps=106 bps)
Queuing time=102 (10 routers each having a queuing time of 2)
=20
Processing delay=101 (10 routers each having a processing time of 1)
=10
Answer:1.010030 sec
Explanation:
Given that,
Size of frame given = 5 million bits = 5 × 10^6 bits = 5000000 bits
Queuing time = 2 μs = 2 × 10^-6 sec = 0.000020 sec
Processing time = 1 μs = 1 × 10^-6 sec = 0.00001 sec
Length of link will be denoted as distance d = 2000 Km = 2000 × 10^3 m
Then the speed of light also known as Propagation speed will be = 2x10^8m/s
Bandwidth or rather, B = 5 Mbps = 5 × 10^6 bps
For delay or latency, the following formula is included
Delay or latency = Propagation time + Transmission time + Queuing time + Processing time
Propagation time = Distance/Propagation speed=
2000×10³/2x 10^8
=0.01 sec
Transmission time =
Frame of size/Bandwidth
5000000×10³/5x10^6
=1sec
Now, from the provided equations we will get,
Delay (latency) = 0.01 + 1 + 0.000020 + 0.000010
= 1.010030 sec