Computing end-end delay (transmission and propagation delay)
Consider the figure below, with three links, each with the specified transmission rate and link length.
Assume the length of a packet is 12000 bits. The speed of light propagation delay on each link is 3x10^8 m/sec
Round your answer to two decimals after leading zeros
Question List
1. What is the transmission delay of link 1?
2. What is the propogation delay of link 1?
3. What is the total delay of link 1?
4. What is the transmission delay of link 2?
5. What is the propogation delay of link 2?
6. What is the total delay of link 2?
7. What is the transmission delay of link 3?
8. What is the propogation delay of link 3?
9. What is the total delay of link 3?
10. What is the total delay?
Solution
Link 1 transmission delay = L/R = 12000 bits / 100 Mbps = 0.00012 seconds
Link 1 propagation delay = d/s = ()2 Km) * 1000 / 3*10^8 m/sec = 6.67E-6 seconds
Link 1 total delay = d_t + d_p = 0.00012 seconds + 6.67E-6 seconds = 0.00013 seconds
Link 2 transmission delay = L/R = 12000 bits / 1 Mbps = 0.012 seconds
Link 2 propagation delay = d/s = ()500 Km) * 1000 / 3*10^8 m/sec = 0.0017 seconds
Link 2 total delay = d_t + d_p = 0.012 seconds + 0.0017 seconds = 0.014 seconds
Link 3 transmission delay = L/R = 12000 bits / 10 Mbps = 0.0012 seconds
Link 3 propagation delay = d/s = ()1 Km) * 1000 / 3*10^8 m/sec = 3.33E-6 seconds
Link 3 total delay = d_t + d_p = 0.0012 seconds + 3.33E-6 seconds = 0.0012 seconds
The total delay = d_L1 + d_L2 + d_L3 = 0.00013 seconds + 0.014 seconds + 0.0012 seconds = 0.015 seconds
That's incorrect
That's correct
The answer was: 0.00012
The answer was: 6.67E-6
The answer was: 0.00013
The answer was: 0.012
The answer was: 0.0017
The answer was: 0.014
The answer was: 0.0012
The answer was: 3.33E-6
The answer was: 0.0012
The answer was: 0.015