Verifiable Encryption

Related Concepts

Zero Knowledge Proof

Definition

Verifiable encryption is an encryption scheme where one can prove some property of a message m, while the message is given in an encrypted form. When an encryption scheme is secure, the encryption E(m) should reveal no information regarding m. But this property may not be suitable in cases where checking some property of the encrypted content is required before processing the encrypted data. Verifiable encryption allows a verifier to check certain property of the content that is encrypted.

Applications

An example of such a case is a key escrow_scheme. In a typical key escrow scheme, when a sender sends an encrypted message, he is required to encrypt the key which he used to encrypt the message, and the encryption of the key is by using the escrow agent’s public key. This way, the escrow agent can always obtain the key used to encrypt the message, and thus the escrow agent can read the message. However, the sender can fool the escrow...