Symmetric and Asymmetric Encryption

• What is the process of encoding a message called?

  Encryption
• What is the purpose of encryption?

  To ensure only sender and recipient can read
• What was one of the first forms of encryption?

  The Caesar cipher
• How does the Caesar cipher work?

  It replaces letters with others a fixed distance away
• What is required to decrypt a message encoded with the Caesar cipher?

  The recipient needs to know the key
• Why is symmetric encryption considered less secure?

  Key interception or duplication can occur
• What is symmetric encryption?

  Using a single key for both encryption and decryption
• What is a potential risk of symmetric encryption?

  Key interception or duplication
• What is asymmetric encryption?

  Using two different keys for encryption and decryption
• What is a key pair in asymmetric encryption?

  Two keys: public and private
• What is the role of the public key?

  It can be shared publicly
• What should never be shared in asymmetric encryption?

  The private key
• How does the public-private key method enhance security?

  It allows secure communication without sharing private keys
• What happens when Jane uses my public key to encrypt a message?

  Only I can decrypt it with my private key
• What does encrypting a message with my private key signify?

  It confirms the message's authenticity
• What is a combined encryption key?

  Using both public and private keys for encryption
• What are the four assurances provided by the public-private key system?

  Confidentiality, authenticity, integrity, and non-repudiation
• What is an encryption key?

  A sequence of alphanumeric characters
• What is a popular standard for encryption keys mentioned in the video?

  256-bit encryption key
• How many possible combinations does a 256-bit encryption key have?

  $2^{256}$ possible combinations
• How long would it take to crack a 256-bit encryption key?

  Billions of billions of years
• What analogy is often used regarding the time to crack a 256-bit key?

  It would take longer than the universe's age