GlossaryΒΆ

authentication
The process of verifying that a message was created by a specific individual (or program). Like encryption, authentication can be either symmetric or asymmetric. Authentication is necessary for effective encryption.
ciphertext
The encoded data, it’s not user readable. Potential attackers are able to see this.
ciphertext indistinguishability
This is a property of encryption systems whereby two encrypted messages aren’t distinguishable without knowing the encryption key. This is considered a basic, necessary property for a working encryption system.
decryption
The process of converting ciphertext to plaintext.
encryption
The process of converting plaintext to ciphertext.
key
Secret data is encoded with a function using this key. Sometimes multiple keys are used. These must be kept secret, if a key is exposed to an attacker, any data encrypted with it will be exposed.
nonce
A nonce is a number used once. Nonces are used in many cryptographic protocols. Generally, a nonce does not have to be secret or unpredictable, but it must be unique. A nonce is often a random or pseudo-random number (see Random number generation). Since a nonce does not have to be unpredictable, it can also take a form of a counter.
plaintext
User-readable data you care about.
private key
This is one of two keys involved in public-key cryptography. It can be used to decrypt messages which were encrypted with the corresponding public key, as well as to create signatures, which can be verified with the corresponding public key. These must be kept secret, if they are exposed, all encrypted messages are compromised, and an attacker will be able to forge signatures.
public key
This is one of two keys involved in public-key cryptography. It can be used to encrypt messages for someone possessing the corresponding private key and to verify signatures created with the corresponding private key. This can be distributed publicly, hence the name.
public-key cryptography
asymmetric cryptography
Cryptographic operations where encryption and decryption use different keys. There are separate encryption and decryption keys. Typically encryption is performed using a public key, and it can then be decrypted using a private key. Asymmetric cryptography can also be used to create signatures, which can be generated with a private key and verified with a public key.
symmetric cryptography
Cryptographic operations where encryption and decryption use the same key.
text
This type corresponds to unicode on Python 2 and str on Python 3. This is equivalent to six.text_type.