Data Communications Exam 2 Questions
and Answers Graded A+
What are the four components of delay? - Correct answer-Transmission,
Propagation, Processing, and Queueing
Where are queues likely to form? - Correct answer-Processor or Link
What is the minimum packet size? What is this packet size usually used for? -
Correct answer-Minimum packet size of 40 bytes, typically used for multimedia.
Maximum Packet Size - Correct answer-1500 bytes (Web/file xfer)
Average Packet Size - Correct answer-300 bytes (typical data)
Transmission delay is... - Correct answer-Time it takes to signal all bits on link
Propagation delay is... - Correct answer-Time it takes for signal to travel
Transmission Delay = - Correct answer-8B/R where B = bytes and R is
transmission speed
Number of packets in pps for transmition - Correct answer-1/(Transmission Delay)
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, How do you calculate the "Burstiness" of a network - Correct answer-Peak Rate /
AverageRate
The service capacity (μ) is... - Correct answer-μ is the smaller of the processor or
output port capacity
and is measured in pps (packets per second)
μ^(-1) defines what? - Correct answer-The service time per packet
How is N defined in regards to utilization/capacity? - Correct answer-N = ρ/(1-ρ)
Propagation Delay - Correct answer-Distance/(2*10^8)
Source Activity Probability = - Correct answer-1/Burstiness =
AverageRate/PeakRate
w (wait time) - Correct answer-(1/μ)(ρ/(1-ρ))
Total Delay - Correct answer-Total delay is the sum of the processing, propagation,
queue, and transmission delay
Probability that there are a certain amount of packets in queue - Correct answer-
ρ^B
where ρ = utilization
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and Answers Graded A+
What are the four components of delay? - Correct answer-Transmission,
Propagation, Processing, and Queueing
Where are queues likely to form? - Correct answer-Processor or Link
What is the minimum packet size? What is this packet size usually used for? -
Correct answer-Minimum packet size of 40 bytes, typically used for multimedia.
Maximum Packet Size - Correct answer-1500 bytes (Web/file xfer)
Average Packet Size - Correct answer-300 bytes (typical data)
Transmission delay is... - Correct answer-Time it takes to signal all bits on link
Propagation delay is... - Correct answer-Time it takes for signal to travel
Transmission Delay = - Correct answer-8B/R where B = bytes and R is
transmission speed
Number of packets in pps for transmition - Correct answer-1/(Transmission Delay)
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
, How do you calculate the "Burstiness" of a network - Correct answer-Peak Rate /
AverageRate
The service capacity (μ) is... - Correct answer-μ is the smaller of the processor or
output port capacity
and is measured in pps (packets per second)
μ^(-1) defines what? - Correct answer-The service time per packet
How is N defined in regards to utilization/capacity? - Correct answer-N = ρ/(1-ρ)
Propagation Delay - Correct answer-Distance/(2*10^8)
Source Activity Probability = - Correct answer-1/Burstiness =
AverageRate/PeakRate
w (wait time) - Correct answer-(1/μ)(ρ/(1-ρ))
Total Delay - Correct answer-Total delay is the sum of the processing, propagation,
queue, and transmission delay
Probability that there are a certain amount of packets in queue - Correct answer-
ρ^B
where ρ = utilization
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
