Bootstrapping

Bootstrapping is basically “recrypting” procedure to get a “fresh” ciphertextfro-m the noisy ciphertext corresponding to the same plaintext. A scheme is called bootstrappable if it can evaluate its own decryption algorithm circuit [Gentry 2009]. First, the ciphertext is transformed into a bootstrappable ciphertext using squashing. Then, by applying bootstrapping procedure, one gets a “fresh” ciphertext