EECE 446 Exam I Spring 2022
EECE 446 Exam I
Prof. Kredo
Spring 2022
Abbreviated Solutions
During this examination:
• For multiple choice questions, circle the best answer; there will be only one best answer. For multiple
selection questions (those with ), mark all correct answers; there may be any number of correct
answers.
• You may not use any books, notes, calculators, electronic/digital devices, or other material. You must
work individually.
• No blank sheets of paper allowed; use the back of the exam pages if you need scratch paper or run out
of space. Be sure to indicate if any important work is located on the back of a page.
• State any assumptions you make when answering a question.
• Leave your answer as a mathematical expression if you cannot find the numerical solution.
• Show your work for full credit. Correct answers with no work will receive little credit.
• Read each question carefully before you begin answering it. If you need clarification on a problem,
raise your hand and someone will assist you.
• Make sure you have all 5 pages of the exam, counting this page, before you begin.
Question Points Score
1 15
2 25
3 40
4 10
5 10
Total: 100
, EECE 446 Exam I Spring 2022
1. Analyze the network communications in the figure below by answering the following questions. In the
figure, A and B start sending packets at the same time. Variables are defined beside the figure.
D bits of data per packet
H bits of header per packet
P one-way propagation delay in seconds
R line rate in bits/second
(a) [5 points] What is the overall latency for the (c) [5 points] What is the total (aggregate)
communication? goodput for the communication?
(D + H) D
A. +P A.
R L
(D + H) 2D
B. + 2P B.
R L
2 (D + H) (D + H)
C. +P C.
R L
2 (D + H) 2 (D + H)
D. + 2P D.
R L
E. None of the above E. None of the above
(b) [5 points] What is the total (aggregate)
throughput for the communication?
D
A.
L
2D
B.
L
(D + H)
C.
L
2 (D + H)
D.
L
E. None of the above
Page 2 of 5
EECE 446 Exam I
Prof. Kredo
Spring 2022
Abbreviated Solutions
During this examination:
• For multiple choice questions, circle the best answer; there will be only one best answer. For multiple
selection questions (those with ), mark all correct answers; there may be any number of correct
answers.
• You may not use any books, notes, calculators, electronic/digital devices, or other material. You must
work individually.
• No blank sheets of paper allowed; use the back of the exam pages if you need scratch paper or run out
of space. Be sure to indicate if any important work is located on the back of a page.
• State any assumptions you make when answering a question.
• Leave your answer as a mathematical expression if you cannot find the numerical solution.
• Show your work for full credit. Correct answers with no work will receive little credit.
• Read each question carefully before you begin answering it. If you need clarification on a problem,
raise your hand and someone will assist you.
• Make sure you have all 5 pages of the exam, counting this page, before you begin.
Question Points Score
1 15
2 25
3 40
4 10
5 10
Total: 100
, EECE 446 Exam I Spring 2022
1. Analyze the network communications in the figure below by answering the following questions. In the
figure, A and B start sending packets at the same time. Variables are defined beside the figure.
D bits of data per packet
H bits of header per packet
P one-way propagation delay in seconds
R line rate in bits/second
(a) [5 points] What is the overall latency for the (c) [5 points] What is the total (aggregate)
communication? goodput for the communication?
(D + H) D
A. +P A.
R L
(D + H) 2D
B. + 2P B.
R L
2 (D + H) (D + H)
C. +P C.
R L
2 (D + H) 2 (D + H)
D. + 2P D.
R L
E. None of the above E. None of the above
(b) [5 points] What is the total (aggregate)
throughput for the communication?
D
A.
L
2D
B.
L
(D + H)
C.
L
2 (D + H)
D.
L
E. None of the above
Page 2 of 5
