### 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 / 10 Mbps = 0.0012 seconds

Link 1 propagation delay = d/s = ()1 Km) * 1000 / 3*10^8 m/sec = 3.33E-6 seconds

Link 1 total delay = d_t + d_p = 0.0012 seconds + 3.33E-6 seconds = 0.0012 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 = ()3 Km) * 1000 / 3*10^8 m/sec = 1.00E-5 seconds

Link 3 total delay = d_t + d_p = 0.0012 seconds + 1.00E-5 seconds = 0.0012 seconds

The total delay = d_L1 + d_L2 + d_L3 = 0.0012 seconds + 0.014 seconds + 0.0012 seconds = 0.016 seconds

That's incorrect

That's correct

The answer was: 0.0012

The answer was: 3.33E-6

The answer was: 0.0012

The answer was: 0.012

The answer was: 0.0017

The answer was: 0.014

The answer was: 0.0012

The answer was: 1.00E-5

The answer was: 0.0012

The answer was: 0.016