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Identity-based encryption

Identity-based encryption (IBE) definition

Identity-based encryption (or IBE) is a method that encrypts messages with a user’s identity (like their email address) instead of a public key. IBE can be a great option when companies want to simplify encryption for the user. It is commonly used in secure email communication, access control systems, and messaging.

See also: AES encryption

How identity-based encryption works

  1. 1.In most systems, a trusted authority called the Private Key Generator (PKG) manages all keys.
  2. 2.When new users join, they provide their identity info (like email or username) to the PKG.
  3. 3.The PKG creates a unique private key for each user using a master secret key and their identity. This private key is used for decryption.
  4. 4.Senders encrypt messages using the recipient's identity as the key — no need for the recipient's public key.
  5. 5.When the recipient receives the message, they ask the PKG for their private key. The PKG verifies the recipient and gives them the key.
  6. 6.The recipient can decrypt the message and access its contents securely.
  7. 7.The PKG also can revoke a user’s private key (for example, if it’s compromised).

Examples of IBE in use

  • An insurance firm may use this encryption method to secure its email system.
  • Universities may use IBE to manage access to various campus buildings.
  • An instant messaging app may use identity-based encryption to let users communicate privately.
  • A hospital may use IBE to securely access patient medical records.
  • File-sharing services may use IBE to boost user security and privacy.