Computer Security

The details
Computer Science and Electronic Engineering (School of)
Colchester Campus
Postgraduate: Level 7
Thursday 03 October 2024
Friday 13 December 2024
25 April 2024


Requisites for this module



Key module for

MSC G40012 Advanced Computer Science,
MSC G400CH Advanced Computer Science,
MSC H60112 Computer Networks and Security,
MSC G456N1 Computing,
MSC GH64N3 Computer Systems Engineering,
MSCIG402 Computer Science,
MSCII100 Computer Science (Integrated Masters, Including Placement Year)

Module description

This course gives an introduction to computer security and cryptography, from theory to practical as well as giving students the necessary background on making data stored and communicated in a safe manner.

Introductory material is independent of any programming language but the consideration of Python is used, partly because its open-source nature facilitates this and partly because it is widely used on server systems. The introduction to cryptography will be used to consider its use in encryption and message authentication.

Module aims

The aim of this module is:

  • To introduce computer security and cryptography and consider security of data for storage and communications.

Module learning outcomes

By the end of this module, students will be expected to be able to:

  1. List and explain common data security vulnerabilities.

  2. List and explain different types of attack on data confidentiality, availability and integrity.

  3. Explain, apply and analyse weak and strong data security cryptography tools and methods.

  4. Evaluate the use of cryptography in certification and authentication.

Module information

Outline Syllabus

1. Introduction:
Principles of security and privacy, introduction to the different types of computer attack
Common security policies, techniques and tools:
Good administrative procedures for computer systems. Data security (e.g. good backup policy).
Combating social engineering. Tools for identifying system vulnerabilities. Monitoring for break-ins. Recovering from a break-in.

2. Overview of Encryption:
Applications of encryption to computer security. Types of encryption algorithms.
Examples of encryption algorithms commonly used.

3. Theoretical Background for Cryptography:
Fundamentals and principles used in cryptography including, binary arithmetic, prime numbers, exponential and logarithmic operations, Euler’s theorem Galois fields and Chinese Remainder Theorem.

4. Symmetric Encryption:
Perfect secrecy and the one-time pad, Feistel Cypher, DES (Data Encryption Standard), AES (Advanced Encryption Standard). Key generation algorithms.

5. Assymetric Encryption:
Public-key cryptography. Anonymous key exchange (Diffie-Hellman). RSA (Rivest-Shamir-Adelman)

6. High-level Ciphers:
Block ciphers (substitution, transposition, product), Stream ciphers and Modes of operation (ECB, CBC, CFB, OFB)

7. Message Authentication:
Hashing (SHA and HMAC) and Digital signature schemes: DSA (Digital Signature Algorithm) and DSS (Digital Signature Standard)

8. Advanced Cryptography
Elliptic Curve Cryptography and post-quantum crypto: signatures and key exchange

Learning and teaching methods

This module will be delivered via:

  • Theoretical knowledge is imparted through live lectures, emphasizing core principles.
  • Practical skills are honed in laboratory sessions, where real-world applications are explored.


This module does not appear to have a published bibliography for this year.

Assessment items, weightings and deadlines

Coursework / exam Description Deadline Coursework weighting
Coursework   Assignment 1 - Lab Report    33.33% 
Coursework   Assignment 2 - Lab Report    33.34% 
Written Exam  Progress Test 1 (In person, MCQ Moodle Based Test, Closed Book)     33.33% 
Exam  Main exam: In-Person, Open Book (Restricted), 120 minutes during Early Exams 
Exam  Reassessment Main exam: In-Person, Open Book (Restricted), 120 minutes during September (Reassessment Period) 

Exam format definitions

  • Remote, open book: Your exam will take place remotely via an online learning platform. You may refer to any physical or electronic materials during the exam.
  • In-person, open book: Your exam will take place on campus under invigilation. You may refer to any physical materials such as paper study notes or a textbook during the exam. Electronic devices may not be used in the exam.
  • In-person, open book (restricted): The exam will take place on campus under invigilation. You may refer only to specific physical materials such as a named textbook during the exam. Permitted materials will be specified by your department. Electronic devices may not be used in the exam.
  • In-person, closed book: The exam will take place on campus under invigilation. You may not refer to any physical materials or electronic devices during the exam. There may be times when a paper dictionary, for example, may be permitted in an otherwise closed book exam. Any exceptions will be specified by your department.

Your department will provide further guidance before your exams.

Overall assessment

Coursework Exam
30% 70%


Coursework Exam
30% 70%
Module supervisor and teaching staff
Dr Michael Barros, email: m.barros@essex.ac.uk.
Dr Michael Barros
School Office, email: csee-schooloffice (non-Essex users should add @essex.ac.uk to create full e-mail address), Telephone 01206 872770



External examiner

Dr Anthony Olufemi Tesimi Adeyemi-Ejeye
Available via Moodle
Of 32 hours, 21 (65.6%) hours available to students:
11 hours not recorded due to service coverage or fault;
0 hours not recorded due to opt-out by lecturer(s).


Further information

* Please note: due to differing publication schedules, items marked with an asterisk (*) base their information upon the previous academic year.

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