PowerPoint Presentation

Introduction to Cryptographic Algorithms. Explore the fascinating world of cryptography, and learn how it secures our digital world. We will delve into the key types of cryptographic algorithms: symmetric and asymmetric..

What is Cryptography?. The art of securing information by encoding it to protect its confidentiality, integrity, and authenticity..

Why Cryptographic Algorithms Matter. 1. Data Confidentiality.

Types of Cryptographic Algorithms. Symmetric-key.

Symmetric Cryptographic Algorithms. Examples: AES, DES..

How Symmetric Encryption Works. 1. Plaintext. 2. Encryption (with key).

Asymmetric Cryptographic Algorithms. Examples: RSA, ECC.

How Asymmetric Encryption Works. Plaintext. Encryption (with public key).

Symmetric vs. Asymmetric Cryptography. 1. Key Usage.

Key Takeaways. Cryptography is essential for secure communication, data integrity, and authentication in a digital world..

Symmetric Encryption: Concepts, History, and Applications.

Introduction to Cryptographic Algorithms. Key Categories: - Symmetric Encryption: Same key for encryption and decryption. - Asymmetric Encryption: Different keys for encryption (public) and decryption (private). - Hybrid Systems: Combine symmetric and asymmetric methods for efficiency and security..

Symmetric Encryption Basics. Uses the same key for encryption (E) and decryption (D). Faster and suitable for large data volumes. Mathematical Representation: Encryption: C = E(M, K) Decryption: M = D(C, K) Key Challenge: Securely sharing the secret key..

[image] A diagram of a person and person working on computers Description automatically generated.

XOR Functionality in Symmetric Encryption. Explanation: - XOR (Exclusive OR) is a fundamental operation in encryption. - Bit-level transformation: A ⊕ B Example: - Input 1: 1010 (Message) - Input 2: 1100 (Key) - XOR Result (Ciphertext): 0110 - Decryption (XOR Ciphertext with Key): 1010.

Historical Milestones in Symmetric Encryption. 1. Data Encryption Standard (DES): - Developed by IBM (1970s), 56-bit key, 64-bit block size. - Vulnerable by 1998 (broken in 56 hours). 2. Triple DES (3DES): - Enhanced DES by applying encryption three times. - Stronger but inefficient with modern computing power. 3. Advanced Encryption Standard (AES): - Adopted in 2002. - Key lengths: 128, 192, 256 bits..

DES and Its Vulnerability. Features: - Key length: 56 bits. - Popular for 20 years. Weakness: - Limited key size led to brute-force vulnerabilities. Example: - Ciphertext: 3DE45ACB - Key: Small range allowed cracking in 56 hours (EFF, 1998)..

Triple DES (3DES). Mechanism: - Encrypt → Decrypt → Encrypt. - Key size: 168 bits. Challenges: - Computationally intensive. - Vulnerable with increasing processing power. Example: - Input Message: 01010101 - Key 1, Key 2, Key 3 used sequentially..

Advanced Encryption Standard (AES). Introduction: - Federal standard since 2002. - Designed to replace DES and 3DES. Features: - Key sizes: 128, 192, 256 bits. - Block size: 128 bits. Advantages: - Robust against brute force. - Efficient for modern computing..

Conclusion. Symmetric encryption remains vital for fast and efficient security. - Evolution from DES to AES highlights the impact of technological advancements. - XOR and block cipher techniques underpin its operation..

Asymmetric Encryption. Public key cryptography.

Asymmetric Encryption. Public Key: Shared with everyone to encrypt data. Private Key: Kept secret and used to decrypt data..

Why Asymmetric Encryption?. Eliminates the need for pre-sharing secret keys (as required in symmetric encryption). Enables secure communication over untrusted channels. Used extensively in secure protocols like HTTPS, SSL/TLS, and email encryption..

Introduction to RSA(Rivest-Shamir-Adleman). It use two very basic maths concepts: Modular Arithmetic Prime Numbers.

How RSA Works. Step 1: Select Big Prime Numbers: p = 2 & q = 7 Step 2: Calculate N: N = p * q Step 3: Calculate O: O = (p-1) * (q-1) Step 4: Calculate e: Condition 1: 1 < e < O Condition 2: e should be coprime with N and O. (the GCD should be 1) We choose e = 5 Your public Key: (e, N) Calculate d: Condition : d*e(mod O) = 1 In this case d could be 5, 11, 17, We choose 11. Your private Key: (d, N).

Encrypting. Suppose my Data is 2. Encrypted data Public key = (5, 14) 25 mod 14 = 4 (This is my encrypted text) Decryption Private Key = (11, 14) 411 mod 14 = 2.

Why it is secure. Difficulty of Factorizing N into two prime numbers p and q. Key size is usually 2048 bit. Classical Algorithm have exponential time complexity. General Number Field Sieve (GNFS) needs billions of years..

[image] Number Field Sieve exp(1.9 log(n1/3) * log(log(n))2/3) Shor's Algorithm 500 1000 log(n3) 1500 2000 Number of bits.

Applications of Cryptography.

Online Banking and E-commerce. encrypting sensitive data like card details, bank account numbers, and passwords..

Messaging Apps. Apps like WhatsApp use cryptography called end-to-end encryption..

Secure Websites (HTTPS). information you type, like login credentials or personal details, is secure. It’s done through SSL/TLS protocols..

Digital Signatures. Digital signatures act like a stamp of authenticity for digital files..

Cloud Storage. Cryptography protects files uploaded to cloud services (like Google Drive or Dropbox)..

[image]. Government and Military Communication. Protect confidential information, ensuring that sensitive communications and plans remain secret..

Wi-Fi Security. encryption protocols like WPA2, which protect your internet connection from unauthorized users..

Blockchain and Cryptocurrencies. Secures cryptocurrency transactions. It also protects your cryptocurrency wallet with a private key..

[image] VOTE. Electronic Voting. votes are securely transmitted and cannot be altered or traced back to the voter, maintaining privacy..