Encryption

Encryption

The process of converting data into an unreadable format.

Plain Text

Data before applying encryption.

Cipher Text

Data after applying encryption.

Key Encryption

Ensures authenticity, integrity, confidentiality, and non-repudiation of a message.

Public Key

A key that is shared publicly and used to encrypt data, which can be decrypted with its matching private key.

Private Key

A key that is never shared and is used to decrypt data encrypted with its matching public key.

Symmetric Encryption

Encryption using a single shared key for both encryption and decryption.

Disadvantages of Symmetric Encryption

Keys must be exchanged securely, compromised keys can decrypt messages, and it cannot ensure data origin or integrity.

Asymmetric Encryption

Encryption that uses a pair of keys: public key for encryption and private key for decryption.

Symmetric vs Asymmetric: Number of Keys

Symmetric uses 1 key, while Asymmetric uses 2 keys.

Symmetric vs Asymmetric: Key Sharing

Symmetric shares one key, while Asymmetric only shares the public key.

Asymmetric vs Symmetric: Speed of Encryption

Symmetric encryption is generally faster than asymmetric encryption due to simpler algorithms.

Confidentiality

Only the intended recipient should be able to decrypt the message.

Authenticity

Receiver must know who sent the ciphertext.

Integrity

The message must not be modified during transmission.

Non-repudiation

Neither sender nor receiver should be able to deny involvement in the transmission.

Quantum Cryptography

An encryption system using the properties of photons to produce virtually unbreakable encryption.

Advantages of Quantum Cryptography

More secure, can detect eavesdropping, supports longer keys, and is almost un-hackable.

Disadvantages of Quantum Cryptography

Works only for short distances, high maintenance costs, lacks features like digital signatures, and has a high error rate.