Cryptography and Network Security Review

Vocabulary flashcards covering core cryptography concepts, cipher characteristics, mathematical foundations, and blockchain consensus mechanisms.

A5/1

A stream cipher used primarily in GSM (2G) networks to encrypt voice communication; it uses 3 Linear Feedback Shift Registers (LFSRs) and a 64-bit key, making it vulnerable to brute force attacks due to its small key size.

Brute Force Attack

An attack method that attempts to decrypt data by testing every possible key until the correct one is found.

AES-256

A symmetric encryption algorithm considered secure against brute-force attacks today and recommended as the default standard when cryptographic strength is critical.

Symmetric Encryption

A form of cryptosystem where the exact same key is used for both encryption and decryption.

Key Space Size

The primary factor determining the cryptographic strength of an encryption algorithm.

3DES

A legacy encryption algorithm that is less commonly used today because it is slower and less efficient compared to AES.

Password Cracking Requirement

The specific hashing method used for the passwords, which is the most critical item to identify before executing an attack on hashed passwords.

Public Key (Asymmetric Encryption)

The recipient's key used by a sender to encrypt a message in asymmetric or public key cryptography.

Private Key (Digital Signatures)

The sender's secret key used to digitally sign messages or emails, thereby providing nonrepudiation.

TLS Cryptographic Transition

The architectural practice of starting sessions with asymmetric encryption and transitioning to symmetric keys to overcome the speed and computational overhead limitations of asymmetric cryptography.

Diffie-Hellman

A cryptographic protocol that allows two parties to generate a shared secret key over an insecure channel.

Message Authentication Code (MAC)

An authentication construct that requires a shared secret key between sender and receiver to authenticate a message, distinguishing it from an unkeyed hash function.

Elliptic Curve Cryptography (ECC)

An asymmetric encryption algorithm operating on points on a curve over a field; it provides equal security with smaller key sizes, faster computation, and lower power consumption compared to RSA.

Elliptic Curve Discrete Log Problem

The underlying mathematical problem upon which Elliptic Curve Cryptography (ECC) security is established.

RSA

An asymmetric encryption algorithm based on the mathematical difficulty of factoring large prime numbers that supports digital signatures.

Merkle Root

A cryptographic structure that uniquely represents the entire set of transaction hashes in a block so that integrity can be verified.

Nonce (Proof of Work)

The number that miners iteratively change until the resulting hash meets the required difficulty target.

Proof of Work (PoW)

A consensus mechanism whose primary disadvantage is high energy consumption.

Proof of Stake (PoS)

A blockchain consensus mechanism that selects block creators based on the amount of assets a participant holds and stakes.

Steganography

The security practice of hiding data inside another file.

Tokenization

The security process of replacing sensitive data with a non-sensitive token.