Cryptography Glossary

Advanced Encryption Standard; a symmetric block cipher with 128-bit blocks and key sizes of 128, 192, or 256 bits.

Encryption using a pair of keys: one public for encryption, one private for decryption.

The process of verifying the identity of a user, device, or other entity in a communication.

A property of cryptographic algorithms where a small change in input causes a significant change in output.

A symmetric cipher that encrypts data in fixed-size blocks using a secret key.

A trusted entity that issues digital certificates binding public keys to verified identities.

An algorithm for performing encryption or decryption, transforming plaintext into ciphertext and vice versa.

The encrypted, unreadable form of a message produced by applying an encryption algorithm.

The property of a hash function that makes it computationally infeasible to find two different inputs that produce the same output.

The study of methods for breaking cryptographic systems and obtaining encrypted information without the key.

The process of converting ciphertext back into readable plaintext using a key or algorithm.

A key exchange protocol allowing two parties to establish a shared secret over an insecure channel.

An electronic document that uses a digital signature to bind a public key with an identity.

Public-key cryptography based on elliptic curves, offering strong security with smaller key sizes than RSA.

The process of converting readable plaintext into unreadable ciphertext to protect its confidentiality.

A one-way function that maps data of arbitrary size to a fixed-size output, used for integrity verification.

Hash-based Message Authentication Code; a mechanism combining a hash function with a secret key for message authentication.

A piece of information (a parameter) that determines the functional output of a cryptographic algorithm.

Assurance that the sender of a message cannot deny having sent it, typically provided by digital signatures.

A number used only once in a cryptographic protocol to prevent replay attacks.

The original, readable form of a message before encryption is applied.

A widely used public-key cryptosystem whose security relies on the difficulty of factoring large composite numbers.

Encryption where the same key is used for both encryption and decryption of data.

Transport Layer Security; a protocol providing encrypted communication over computer networks, successor to SSL.

Exclusive OR; a bitwise operation fundamental to many encryption algorithms where output is 1 only when inputs differ.