Two delays that contribute to the total end-to-end delay in networks are propagation delay and transmission delay. Explain what these two delays are and show how to calculate these delays.
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Key Concepts
- Transmission delay L/R
- Propagation delay d/s
- Packet length
- Link rate
- Distance
Answer Approach
- Define transmission delay in terms of pushing bits onto the link.
- Define propagation delay in terms of a bit travelling the link.
- Give the formula and units for each.
Full Answer
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Transmission delay is the time to push all bits of a packet onto the link: L/R, where L is the packet length in bits and R the link rate in bits/s. Propagation delay is the time for a bit to travel from one end of the link to the other: d/s, where d is the link length and s the propagation speed of the medium (about 2 × 10^8 m/s).
d_trans = L / Rd_prop = d / sShortcuts: K concepts · A approach · F answer · R reviewed · B bookmark · ← / → previous / next