CGGI (Cheon-Gentry-Goldwasser-Ishai) Scheme
The CGGI scheme, proposed by Cheon, Gentry, Goldwasser, and Ishai, is a homomorphic encryption scheme that enhances efficiency through bootstrapping.
Key Components
- Secret Key Generation: The secret key is generated based on the LWE (Learning with Errors) problem.
- Public Key Generation: The public key is composed of the secret key and LWE samples.
- Encryption: Encrypts messages to generate LWE ciphertexts.
- Decryption: Decrypts the ciphertexts to restore the original message.
Homomorphic Operations
The CGGI scheme supports complex operations efficiently through effective bootstrapping.
- Homomorphic Addition: Performed through the addition of LWE samples.
- Homomorphic Multiplication: Executed through the multiplication of LWE samples while maintaining efficiency via bootstrapping.