Midterm Examination
Term: Winter___ Year: ___2024_
Student name: _______________________ ________________________ _________________________
(First name) (Middle name) (Last name)
Waterloo student identification number:
_______________________________________________________
Course abbreviation and number: ______ECE 628_______________
Course title: _____Computer Network Security________________________________________
Section(s): _______________001____________________________________
Sections combined course(s): _________________________________________________________________
Section numbers of combined course(s): ________________________________________________________
Name of instructor(s): _______Guang Gong________________________________________
Date of exam: _____ Start at 11:59am ET, Monday, Feb 26
Due at 11:59pm ET, Thursday, Feb 29, submit it to Crowdmark.__
Duration of exam: Take home exam, the duration is listed above, 3 and half days. __________________________________
Number of exam pages: (includes cover page) 6 pages
Exam type: (select one) ⬜ Closed book ⬜ Special materials ✓⬜ Open book
The marking scheme is shown besides the questions and [50] constitutes full marks. Note that the questions are not of equal
difficulty.
Marking scheme:
Question Score
1
2
3
4
5
This study source was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 22:55:10 GMT -06:00
https://www.coursehero.com/file/228908936/628W24-middle-termexamquestionsheetspdf/
, @G. Gong, ECE 628 Computer Network Security, Winter 2024 1
Question 1. (10 marks) Consider the four classes of attacks to computer networks for
basic protections on data confidentiality, and authenticity and integrity. For each of the
following for attacks, identify a case in the real world the system could be broken. You
need to provide analysis including attacker’s knowledge about the system (e.g., it can only
launch the attack remotely or can physical access the system), complexity for breaking the
system (e.g., recovering the plaintext or extract the key for breaking confidentiality), and
countermeasures.
(a) [4] cryptographic attacks, i.e., break crypto algorithms and protocols.
• Consider a cipher system whether resists to CPA attack or CCA attacks
• An entity authentication using both MAC and digital signatures which are se-
cure under existentially unforgeable under an adaptive chosen-message attack (EU-
CMA) or just secure. Explain what attacks those schemes can resist.
(b) [2] physical threat such as conducting side-channel attacks, implementation errors;
(c) [2] identify at least two attacks on wireless transmission; and
(d) [2] the man-in-the-middle (MITM) attacks: active MITM and relay attack.
This study source was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 22:55:10 GMT -06:00
https://www.coursehero.com/file/228908936/628W24-middle-termexamquestionsheetspdf/
Term: Winter___ Year: ___2024_
Student name: _______________________ ________________________ _________________________
(First name) (Middle name) (Last name)
Waterloo student identification number:
_______________________________________________________
Course abbreviation and number: ______ECE 628_______________
Course title: _____Computer Network Security________________________________________
Section(s): _______________001____________________________________
Sections combined course(s): _________________________________________________________________
Section numbers of combined course(s): ________________________________________________________
Name of instructor(s): _______Guang Gong________________________________________
Date of exam: _____ Start at 11:59am ET, Monday, Feb 26
Due at 11:59pm ET, Thursday, Feb 29, submit it to Crowdmark.__
Duration of exam: Take home exam, the duration is listed above, 3 and half days. __________________________________
Number of exam pages: (includes cover page) 6 pages
Exam type: (select one) ⬜ Closed book ⬜ Special materials ✓⬜ Open book
The marking scheme is shown besides the questions and [50] constitutes full marks. Note that the questions are not of equal
difficulty.
Marking scheme:
Question Score
1
2
3
4
5
This study source was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 22:55:10 GMT -06:00
https://www.coursehero.com/file/228908936/628W24-middle-termexamquestionsheetspdf/
, @G. Gong, ECE 628 Computer Network Security, Winter 2024 1
Question 1. (10 marks) Consider the four classes of attacks to computer networks for
basic protections on data confidentiality, and authenticity and integrity. For each of the
following for attacks, identify a case in the real world the system could be broken. You
need to provide analysis including attacker’s knowledge about the system (e.g., it can only
launch the attack remotely or can physical access the system), complexity for breaking the
system (e.g., recovering the plaintext or extract the key for breaking confidentiality), and
countermeasures.
(a) [4] cryptographic attacks, i.e., break crypto algorithms and protocols.
• Consider a cipher system whether resists to CPA attack or CCA attacks
• An entity authentication using both MAC and digital signatures which are se-
cure under existentially unforgeable under an adaptive chosen-message attack (EU-
CMA) or just secure. Explain what attacks those schemes can resist.
(b) [2] physical threat such as conducting side-channel attacks, implementation errors;
(c) [2] identify at least two attacks on wireless transmission; and
(d) [2] the man-in-the-middle (MITM) attacks: active MITM and relay attack.
This study source was downloaded by 100000899606070 from CourseHero.com on 02-22-2026 22:55:10 GMT -06:00
https://www.coursehero.com/file/228908936/628W24-middle-termexamquestionsheetspdf/
