Cryptography & Security

Cryptography Techniques & Information Security: A Comprehensive Guide

Information Security Basics4.9(98)7h 59m43 lectures13 sections

What you'll learn

  • Understand information security and network concepts
  • Study number theory and its use in cryptography
  • Learn the classical encryption techniques
  • Understand the data encryption standard and block ciphers
  • Understand how a block cipher and random number generators work
  • Explain public key cryptography
  • Understand cryptographic hash functions
  • Learn about digital signatures
  • Know key management and distribution

About this course

This course teaches cryptography and information security from the ground up, with the aim of understanding how to protect data and privacy, not how to attack any system. It starts with the concepts of information security and networks, then an introduction to number theory and its advanced concepts, because it is the mathematical base on which cryptography stands. Next you learn the classical encryption techniques, the data encryption standard, block ciphers and the advanced encryption standard, how a block cipher works, and random number generators. You then move to public key cryptography and advanced encryption algorithms, cryptographic hash functions and message authentication codes, digital signatures, and you finish with key management and distribution. The course is split into ordered lectures and suits computer science students, people interested in cyber security and programmers who want to understand protection in their applications, and a simple background in mathematics is preferred. By the end, you will be able to understand modern and classical encryption methods and know the role of keys and digital signatures in protecting information.

Expected outcomes

  • Comprehensive understanding of encryption and information security principles.
  • Applying encryption techniques to secure data.
  • Efficiently managing keys and digital signatures.
  • Ability to analyze and secure networks and information.

Learner reviews

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  • ★★★★★Eyad A.·منذ 2 شهرشاهد 65٪
  • ★★★★★الحسن ب.·منذ 3 شهرشاهد 100٪

    الكورس جميل جدا استفدت منه

تم عرض كل التقييمات (2)

Course content

1

Information and Network Security Concepts

3 lectures
  1. Information and Network Security Concepts (Lecture 1)Gives an overview of cryptography and its goals: confidentiality, data integrity, authentication and non-repudiation, types of attacks and system vulnerabilities, and the split between cryptography and cryptanalysis.12:56
  2. Information and Network Security Concepts (Lecture 2)Covers threats and vulnerabilities in systems, attacks on messages, the difference between encryption and decryption, and cryptanalysis attack types such as the Cipher Text Only Attack, before moving to single-key encryption types.13:29
  3. Information and Network Security Concepts (Lecture 3)Solves practical problems from an information security worksheet, explaining the steps for a cipher question using a keyword matrix and the rules for two letters in the same row, same column, or at an intersection.20:14
2

Introduction to Number Theory

4 lectures
  1. Introduction to Number Theory (Lecture One)Introduces number theory basics for cryptography: the concept of division with no remainder and divisors, and how to check whether one number divides another using worked examples.5:10
  2. Introduction to Number Theory (Lecture Two)Explains the properties of divisibility in number theory, such as divisibility of sums of multiples, then the division algorithm relating dividend, divisor, quotient and remainder, with examples.14:39
  3. Introduction to Number Theory (Lecture Three)Explains the Euclidean algorithm for finding the greatest common divisor of two numbers, starting with an example listing divisors and then repeated division by the remainder until the remainder reaches zero.13:18
  4. Introduction to Number Theory (Lecture Four)Explains modular arithmetic: the concept of congruence and its properties such as symmetry, adding, subtracting and multiplying under a modulus, the extended Euclidean algorithm, and properties of prime numbers.14:38
3

Advanced Concepts in Number Theory

6 lectures
  1. Advanced Concepts in Number Theory (Lecture One)Explains the Miller-Rabin test for checking whether a large number is prime, its steps of picking a random number and computing modular powers, with a worked example and its probabilistic nature.9:38
  2. Advanced Concepts in Number Theory (Lecture Two)Explains the Chinese Remainder Theorem for solving a system of congruences, with the steps of computing the combined modulus, finding each modular inverse, and combining the results, with a worked example.7:29
  3. Advanced Concepts in Number Theory (Lecture Three)Explains matrices: how size is named by rows and columns, addition and subtraction, matrix-by-matrix multiplication and the dimension-compatibility condition, and multiplying a matrix by a scalar, with worked examples.9:46
  4. Advanced Concepts in Number Theory (Lecture 4)Explains the determinant of a square matrix and how to compute it, then the inverse matrix, and writing a system of equations as coefficient and variable matrices and solving it by multiplying the inverse by the constants.12:24
  5. Advanced Concepts in Number Theory (Lecture 5)Explains solving a linear congruence equation in one variable under a modulus, by adding and subtracting constants and multiplying by the inverse of the coefficient, then handling more than one equation and variable at once.7:29
  6. Advanced Concepts in Number Theory (Lecture 6)Explains Fermat's little theorem and its two conditions, that the modulus is prime and the base is not divisible by it, with a worked example, then Euler's Phi function and how to compute it for primes and for their product.5:32
4

Classical Encryption Techniques

6 lectures
  1. Classical Encryption Techniques (Lecture 1)Explains classical encryption techniques, focusing on substitution ciphers and their types, and the shift (Caesar) cipher with how to encrypt and decrypt by adding and subtracting the key, with an example.8:27
  2. Classical Encryption Techniques (Lecture 2)Explains the Multiplicative Cipher, which replaces addition with multiplication in the formula under a modulus, then the Affine Cipher, which combines multiplication and addition using two keys, with letter-conversion examples.6:54
  3. Classical Encryption Techniques (Lecture 3)Explains the classic Playfair cipher: splitting the text into letter pairs and the encryption rules depending on whether the two letters fall in the same row, the same column, or different rows and columns of the key matrix, with an example.10:21
  4. Classical Encryption Techniques (Lecture 4)Explains the Hill Cipher, which relies on matrix multiplication: converting letters to numbers by their order, building the key matrix, multiplying it by letter pairs and taking the modulus to get the ciphertext.7:17
  5. Classical Encryption Techniques (Lecture 5)Explains decryption in the Hill Cipher by computing the inverse of the key matrix: finding the determinant, taking its modulus and inverse, swapping matrix elements and signs, and previews the Transposition ciphers.5:36
  6. Classical Encryption Techniques (Lecture 6)Explains three types of Transposition ciphers: writing the text in columns and reading it column by column without a key, then reordering the columns according to a key, then combining the two methods.6:02
5

Data Encryption Standard (DES)

2 lectures
  1. Data Encryption Standard (Lecture 1)Explains the difference between block and stream ciphers, and the confusion and diffusion principles an algorithm must satisfy to make the ciphertext hard for an attacker to predict.7:46
  2. Data Encryption Standard (Lecture 2)Explains the structure of the DES standard, based on a Feistel cipher: the initial permutation IP and splitting the text into two halves, round-key generation through PC1 and PC2 permutations, and XOR operations across multiple rounds.10:55
6

Block Ciphers - Advanced Encryption Standard (AES)

3 lectures
  1. Block Ciphers - Advanced Encryption Standard (Lecture 1)Introduces AES as a block cipher newer than DES, explaining how key length relates to the number of rounds, decryption as the inverse of encryption, and the concepts of Block, State and Word.15:02
  2. Block Ciphers - Advanced Encryption Standard (Lecture 2)Walks through the steps of the AES algorithm with a practical example: converting the message and key into matrices, then Add Round Key, followed by round operations such as Sub Bytes, Shift Rows and Mix Columns.9:49
  3. Block Ciphers - Advanced Encryption Standard (Lecture 3)Continues explaining AES rounds: the new round after the initial round and its four operations, including Shift Rows, Mix Columns and Add Round Key, and the use of a new key for each round.14:47
7

Block Cipher Operation

2 lectures
  1. Block Cipher Operation (Lecture 1)Explains multiple, double and triple encryption with DES, why two keys are used in the EDE mode, the drawback of slow speed, and why a replacement such as AES was needed.10:11
  2. Block Cipher Operation (Lecture 2)Explains block cipher modes of operation such as ECB, CBC, CFB and OFB, and how each mode links blocks or uses an initialization vector (IV) to avoid identical outputs.20:00
8

Random Number Generators

2 lectures
  1. Random Number Generators (Lecture 1)Explains random numbers and the difference between TRNG and PRNG and when to use each, then the stream cipher and how it differs from a block cipher by processing data bit by bit.13:43
  2. Random Number Generators (Lecture 2)Explains the RC4 stream cipher and its use in protecting Wi-Fi (WPA), then generators built from several shift registers whose outputs are combined with XOR and a majority rule.12:31
9

Public-Key Cryptography and RSA

3 lectures
  1. Public Key Encryption (Lecture 1)Explains public-key cryptography and how it differs from private-key cryptography, its uses in encryption, digital signatures and key exchange, then the RSA algorithm and its key generation steps.12:31
  2. Public Key Encryption (Lecture 2)Explains the steps of the RSA algorithm with a numeric example: choosing two large primes, computing their product and Euler's function, then generating the public and private keys and using them to encrypt and decrypt.14:50
  3. Public Key Encryption (Lecture 3)Explains why RSA is used and its link to Euler's theorem, the decryption steps, the secrecy of the private key, the difficulty of factoring the number, the need to choose the primes carefully, and how the algorithm evolved with longer numbers.5:44
10

Advanced algorithms In Encryption

3 lectures
  1. Advanced Algorithms in Encryption (Lecture 1)Explains the primitive root of a prime number and how to test whether a number is one by computing its modular powers and checking that no result repeats, with examples.9:36
  2. Advanced Algorithms in Encryption (Lecture 2)Explains the Diffie-Hellman Key Exchange algorithm, which lets sender and receiver agree on a secret key over the internet without sending it directly. It works through an example computing the public and shared keys, then names uses such as SSL and IPSec.12:23
  3. Advanced Algorithms in Encryption (Lecture 3)Explains the ElGamal cryptosystem, which builds on the DHKE algorithm, in its three steps: key generation using a Primitive Root, encryption producing C1 and C2, and decryption, with a numeric example.11:35
11

Cryptographic Hash functions and MAC

5 lectures
  1. Cryptographic Hash Functions and Extended Message Codes (Lecture 1)Explains cryptographic hash functions and their key properties, being one-way and collision-free, their applications, and how they are used in message authentication codes (MAC).14:29
  2. Cryptographic Hash Functions and Extended Message Codes (Lecture 2)Explains the digital signature and how it is verified using a hash function, comparing hash outputs to confirm a message or file was not altered. It also covers hash function properties such as fixed output size, and previews Pre-Image attacks.11:42
  3. Cryptographic Hash Functions and Extended Message Codes (Lecture 3)Compares brute force and cryptanalysis attacks on hash functions, explains an attack that creates many slightly altered copies of a message, and shows how the function processes a message as chained blocks.9:48
  4. Cryptographic Hash Functions and Extended Message Codes (Lecture 4)Explains the structure of the SHA hash function: splitting the message into fixed-size blocks and passing them through a compression function whose output chains from one block to the next, until the final hash value is reached.14:33
  5. Cryptographic Hash Functions and Extended Message Codes (Lecture 5)Explains how SHA processes a message by splitting it into words W, why new versions of the algorithm are developed even when it has not been broken, and how a MAC is used to detect errors and verify the message.16:46
12

Digital Signatures

2 lectures
  1. Digital Signatures (Lecture 1)Introduces the digital signature through the analogy of signing a contract at a company, showing how it confirms the signer's identity and protects the message from tampering, plus the requirements it must meet, such as being unforgeable and not copyable.9:22
  2. Digital Signatures (Lecture 2)Explains digital signature schemes RSA, ElGamal and Digital Signature Standard, the signing and verification processes using private and public keys, a comparison among them, and tying a signature to a specific time to detect tampering.9:05
13

Key Management and Distribution

2 lectures
  1. Key Management and Distribution (Lecture 1)Explains how keys are managed and distributed securely between sender and receiver, the problem of exchanging huge numbers of keys, and the role of the KDC, Master Key and Session Key in connecting users and verifying the other party's identity.12:17
  2. Key Management and Distribution (Lecture 2)Explains Public Key Distribution and the certificates that store user data and the signature, their revocation, the PKI infrastructure, and the hierarchical model of certificate authorities.8:51

Instructor

Eng. Ziad Mahmoud

Eng. Ziad Mahmoud

Teaching assistant at Faros University, Ziad has delivered over 3000 training and consulting hours to more than 600 trainees.
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This course is part of the diploma

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