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Cryptography, Authentication, & Authorization

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Cryptography is the process of encrypting and decrypting data in order to keep that data safe when storing or transmitting it.

Encryption is a way of hiding data by converting it to an encoded format.

Decryption is a way of revealing encrypted data by decoding it from its encoded format.

Symmetric and Asymmetric Encryption

Symmetric encryption uses the same key to encrypt and decrypt data.

Asymmetric encryption uses a public key to encrypt data and a different private key to decrypt data.


Hashing is a one-way process that takes data of any size and represents it as a unique hash value of a fixed size. No matter how large or complex your file is, hashing provides a fast, reliable way to compare files and verify their authenticity.

Hashing can be used to store sensitive data in a secure way.

Authentication & Authorization

Authentication is who you are. Logging in with a username and password is an example of authentication.

Authorization is what you can do. Only being allowed into non-VIP sections of the site is an example of authorization.

Multi-Factor Authentication (MFA)

Multi-factor authentication (MFA) is more secure than single-factor authentication.

Using more forms of authentication makes an asset more secure.

One example of MFA would be:

  • First, logging into a website with a username and password
  • Then, receiving a One-Time Passcode (OTP) that needs to input into the same website


OAuth is a secure framework that makes use of a trusted third-party for authentication.

When a service asked if you want to “Sign in with ____”, this an example of OAuth.

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Introduction to Cybersecurity

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