- "Cryptography, or cryptology, is the practice and study of techniques for secure communication in the presence of adversarial behavior."
The study of techniques used to secure communications and data from intruders.
Symmetric Key Cryptography: This involves using the same key for both encryption and decryption. Examples include DES, AES, and RC4.
Asymmetric Key Cryptography: This involves using different keys for encryption and decryption. Examples include RSA, DSA, and ECC.
Hash Functions: These are mathematical algorithms that take input data and generate a fixed-size, unique output. Examples include SHA-2 and HMAC.
Public Key Infrastructure (PKI): This is a system of certificates, authorities, and other protocols used to establish and manage secure connections over the internet.
Digital Signatures: This involves using a mathematical algorithm to bind a signature to a message or document, thus assuring its authenticity and integrity.
Key Exchange: Techniques for securely exchanging cryptographic keys between parties, such as Diffie-Hellman and Elliptic Curve Diffie-Hellman.
Steganography: This is the practice of hiding information within other information, such as embedding a message in an image or text file.
Cryptanalysis: The study of methods to break cryptographic algorithms and systems, including brute-force attacks, side-channel attacks, and other techniques.
Secure Communication Protocols: Common protocols used for secure communication over the internet, such as SSL/TLS, IPSec, and SSH.
Quantum Cryptography: Cutting-edge cryptographic techniques that leverage the principles of quantum mechanics to achieve unbreakable security.
Symmetric Cryptography: It uses the same key for encryption and decryption, making it faster but less secure.
Asymmetric Cryptography: Also known as Public Key Cryptography, it uses two different keys for encryption and decryption, making it more secure but slower.
Hash Functions: It is a one-way cryptographic function that takes a message and produces a fixed-length string of characters, which is unique for each input, making it useful for digital signatures and password storage.
Block Ciphers: It divides the message into blocks and encrypts each block separately, making it more secure than the symmetric key, but slower.
Stream Ciphers: It encrypts the message one bit at a time, making it faster than block ciphers, but less secure.
Quantum Cryptography: It uses quantum mechanics for secure communication, and is considered to be the most secure cryptographic method available.
Homomorphic Encryption: It allows computation to be performed on encrypted data, without decrypting it first, making it useful for secure cloud computing.
Lattice-based Cryptography: It uses mathematical structures called lattices for encryption and decryption, making it resistant to attacks from quantum computers.
Zero-knowledge Proof: It is a method of proving the authenticity of a statement, without revealing any additional information, making it useful for authentication, privacy, and security.
Post-quantum Cryptography: It is a new cryptographic method developed specifically to resist attacks from quantum computers.
- "Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others."
- "Core concepts related to information security (data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography."
- "Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications."
- "Cryptography prior to the modern age was effectively synonymous with encryption, converting readable information (plaintext) to unintelligible nonsense text (ciphertext), which can only be read by reversing the process (decryption)."
- "The sender of an encrypted (coded) message shares the decryption (decoding) technique only with the intended recipients to preclude access from adversaries."
- "The cryptography literature often uses the names 'Alice' (or 'A') for the sender, 'Bob' (or 'B') for the intended recipient, and 'Eve' (or 'E') for the eavesdropping adversary."
- "Since the development of rotor cipher machines in World War I and the advent of computers in World War II, cryptography methods have become increasingly complex and their applications more varied."
- "Modern cryptography is heavily based on mathematical theory and computer science practice; cryptographic algorithms are designed around computational hardness assumptions."
- "Such schemes, if well designed, are therefore termed 'computationally secure'."
- "Theoretical advances (e.g., improvements in integer factorization algorithms) and faster computing technology require these designs to be continually reevaluated and, if necessary, adapted."
- "While it is theoretically possible to break into a well-designed system, it is infeasible in actual practice to do so."
- "Information-theoretically secure schemes that provably cannot be broken even with unlimited computing power, such as the one-time pad, are much more difficult to use in practice than the best theoretically breakable but computationally secure schemes."
- "The growth of cryptographic technology has raised a number of legal issues in the Information Age."
- "Cryptography's potential for use as a tool for espionage and sedition has led many governments to classify it as a weapon and to limit or even prohibit its use and export."
- "In some jurisdictions where the use of cryptography is legal, laws permit investigators to compel the disclosure of encryption keys for documents relevant to an investigation."
- "Cryptography also plays a major role in digital rights management and copyright infringement disputes with regard to digital media."