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 4000 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 = 4000 bits / 1000 Mbps = 4.00E-6 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 = 4.00E-6 seconds + 6.67E-6 seconds = 1.07E-5 seconds
Link 2 transmission delay = L/R = 4000 bits / 100 Mbps = 4.00E-5 seconds
Link 2 propagation delay = d/s = ()1000 Km) * 1000 / 3*10^8 m/sec = 0.0033 seconds
Link 2 total delay = d_t + d_p = 4.00E-5 seconds + 0.0033 seconds = 0.0034 seconds
Link 3 transmission delay = L/R = 4000 bits / 10 Mbps = 0.0004 seconds
Link 3 propagation delay = d/s = ()3 Km) * 1000 / 3*10^8 m/sec = 1.00E-5 seconds
Link 3 total delay = d_t + d_p = 0.0004 seconds + 1.00E-5 seconds = 0.00041 seconds
The total delay = d_L1 + d_L2 + d_L3 = 1.07E-5 seconds + 0.0034 seconds + 0.00041 seconds = 0.0038 seconds
That's incorrect
That's correct
The answer was: 4.00E-6
The answer was: 6.67E-6
The answer was: 1.07E-5
The answer was: 4.00E-5
The answer was: 0.0033
The answer was: 0.0034
The answer was: 0.0004
The answer was: 1.00E-5
The answer was: 0.00041
The answer was: 0.0038