Course Information
SemesterCourse Unit CodeCourse Unit TitleT+P+LCreditNumber of ECTS CreditsLast Updated Date
8YAZS404Introduction to Cryptology3+0+03520.04.2026

 
Course Details
Language of Instruction Turkish
Level of Course Unit Bachelor's Degree
Department / Program Computer Engineering
Type of Program Formal Education
Type of Course Unit Elective
Course Delivery Method Face To Face
Objectives of the Course The aim of this course is to introduce the fundamental concepts of cryptology and its historical development, and to present the mathematical foundations, algorithmic structures, and engineering applications of classical, modern, and public-key encryption methods in a clear and accessible manner. Within the scope of the course, students are expected to examine encryption and decryption processes through mathematical modeling and analytical problem-solving approaches, and to evaluate the security assumptions and potential weaknesses of different cryptographic methods. In addition, by addressing modern cryptographic systems in terms of key management, security level, and computational complexity, the course aims to develop a systematic and critical perspective on cryptographic methods. The course content will be supported with example applications and problem-solving activities.
Course Content The scope of the course includes the definition of cryptology, its historical development, and basic terminology; the fundamental principles, design approaches, and evaluation criteria of cryptographic systems, as well as a conceptual comparison of symmetric and asymmetric encryption approaches. Encryption and decryption processes, the concept of cryptanalysis, attack models, and evaluation criteria are addressed within the main framework of the course. In addition, an introduction to the concept of digital signatures is provided, and current application areas of cryptography are presented.

The course emphasizes the mathematical foundations of cryptography, including modular arithmetic, relative primality, the concept of modular inverses, and matrices. Among classical encryption methods, Caesar, shift, affine, and Atbash ciphers are examined; within polyalphabetic substitution methods, the Vigenère cipher and the effect of key length on security are discussed; and within transposition-based methods, route, rail fence (sequence), and rectangular transposition ciphers are covered.

As a matrix-based encryption approach, the Hill cipher is analyzed in terms of key selection, invertibility conditions, and basic security considerations. Block-based classical methods such as the Playfair and Four-Square ciphers are also examined, together with their structural weaknesses. In the later part of the course, more advanced classical encryption approaches such as ADFGX and ADFGVX are discussed, along with modern block cipher methods including the DES and AES algorithms. Public-key cryptographic systems, specifically the RSA and El-Gamal algorithms, are addressed with respect to their mathematical foundations, security assumptions, and general characteristics.
Course Methods and Techniques
Prerequisites and co-requisities None
Course Coordinator Asist Prof. Fatma Zehra UZEKMEK
Name of Lecturers Asist Prof. Fatma Zehra UZEKMEK
Assistants None
Work Placement(s) No

Recommended or Required Reading
Resources Leung, L. R. N., Introduction to Cryptography with Coding Theory, Pearson Education, 2019.
Banoth, R., & Regar, R., Classical and Modern Cryptography for Beginners, Springer, 2023.
Klima, R. E., & Sigmon, N. P., Cryptology: Classical and Modern, 2nd Edition, CRC Press, 2019.
Course Notes 1. Narration
2. Question and Answer
3. Discussion
4. Practice and Application
5. Problem Solving
Exams 1 Ara sınav, 1 Final sınavı

Course Category
Mathematics and Basic Sciences %100
Engineering %30
Engineering Design %0
Social Sciences %0
Education %0
Science %0
Health %0
Field %0

Planned Learning Activities and Teaching Methods
Activities are given in detail in the section of "Assessment Methods and Criteria" and "Workload Calculation"

Assessment Methods and Criteria
In-Term Studies Quantity Percentage
Mid-terms 1 % 50
Final examination 1 % 50
Total
2
% 100

 
ECTS Allocated Based on Student Workload
Activities Quantity Duration Total Work Load
Course Duration 14 3 42
Hours for off-the-c.r.stud 14 3 42
Mid-terms 1 2 2
Practice 14 2 28
Final examination 1 2 2
Total Work Load   Number of ECTS Credits 5 116

 
Course Learning Outcomes: Upon the successful completion of this course, students will be able to:
NoLearning Outcomes
1 Explains the fundamental concepts, terminology, and mathematical foundations of cryptology; analyzes the algorithmic structures of classical encryption methods, and evaluates their security properties by applying encryption and decryption processes.
2 Explains the mathematical and algorithmic structures of matrix-based and block encryption methods; evaluates key selection and security criteria from an engineering perspective, and analyzes encryption, decryption, and basic cryptanalysis processes in these methods.
3 Explains the mathematical and algorithmic foundations of public-key cryptographic systems; analyzes key generation and encryption processes, and evaluates the security of these systems in terms of attack models, key size, and computational complexity.

 
Weekly Detailed Course Contents
WeekTopicsStudy MaterialsMaterials
1 Introduction to Cryptology: History and Fundamental Terminology; Cryptographic Principles and Design Criteria; Attack Models and Contemporary Application Areas; Conceptual Comparison of Symmetric and Asymmetric Encryption Approaches; The Concept of Digital Signatures.
2 Mathematical Foundations of Cryptography I
3 Mathematical Foundations of Cryptography II
4 Classical Substitution Ciphers I – Caesar and Shift Cipher Encryption–Decryption Processes, Structural Weaknesses, and Frequency Analysis
5 Classical Substitution Ciphers II – Affine Cipher, Decryption Using the Modular Inverse, Key Space and Attack Possibilities, Atbash Cipher
6 Polyalphabetic Substitution Ciphers – Vigenère Cipher and Decryption Processes, Effect of Key Length on Security
7 Transposition (Permutation) Ciphers I – Route Cipher, Sequence Cipher, and Encryption–Decryption Processes
8 Midterm Exam
9 Transposition (Permutation) Ciphers II – Rectangular Transposition Encryption–Decryption Processes, Key Space, Possible Attack Scenarios
10 Matrix-Based Encryption I – Key Selection, Invertibility Condition and Security Analysis, Hill Cipher
11 Matrix-Based Encryption II – Hill Cipher and Decryption Processes, Implementation and Cryptanalysis
12 Digraphic Ciphers – Playfair and Four-Square Encryption–Decryption Processes, Structural Weaknesses
13 From Classical to Modern Block Encryption Approaches: Advanced Classical Ciphers – ADFGX and ADFGVX Encryption–Decryption Processes. Modern Block Encryption – DES (Data Encryption Standard) and AES (Advanced Encryption Standard): Key Length and Security Evaluation.
14 Asymmetric Cryptography I – RSA Encryption: Mathematical Foundations, Key Generation, Encryption–Decryption Processes, and Security Assumptions
15 Asymmetric Cryptography II – RSA and ElGamal Encryption–Decryption Processes, Algorithmic Structure, Security Assumptions, and Comparative Analysis
16 Final Exam

 
Contribution of Learning Outcomes to Programme Outcomes
P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11
All 5
C1 5
C2 5
C3 5

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