The Calculation Of Fully Homomorphic Encryption On Cloud Platform

Fully Homomorphic Encryption(FHE) system means that the plaintext is encrypted into ciphertext, and it allows to be carried out by arbitrary operations to get another ciphertext and the result of the new ciphertext is equal to the result that operating on plaintext directly. In 2009, great progress was obtained on FHE, Gentry realized a FHE scheme on the basis of ideal lattices. With the continuous development of cloud computing, the advantage of FHE that the ciphertext can be arbitrary carried out becomes manifest. It requires the support of an open source cloud platform to store the ciphertext encrypted by FHE on cloud platform and calculate it. Openstack is an open source project about cloud computing management platform, aimed at providing software for the construction and management of public cloud and private cloud. It is IaaS(Infrastructure as a Service) component that allows anyone to build and deliver their own cloud computing services. This article will focus on the calculation of FHE on the cloud platform. Details are as follows:1)Select an appropriate cloud platform building tool named Openstack by investigating cloud computing virtualization technology and cloud platform, and build a private cloud platform based on Openstack. Firstly, configure the basic environment including network configuration and the installation of NTP, Openstack key package, database and message queue. Then, install several important components, such as certification service Keystone, mirror service Glance, storage service Cinder, computing service Nova, network service Neutron, UI service Horizon and configure each part.2)Research some typical FHE schemes based on integers, such as the DGHV scheme, BDGHV scheme, Cheon's FHE scheme and improved BDGHV scheme, study on the implementating process and construction mechanisms of these algorithms, and compare their advantages and disadvantages, then choose the improved BDGHV scheme as the experimental scheme. Install the environment configurations in Ubuntu required by the environment, such as the GMP open source math library and Crypto++ cryptography library, then complete the FHE scheme with C++ language.3)Deploy the improved BDGHV scheme to the cloud platform, and the processes are as follows: the users upload two encrypted ciphertexts to the cloud, the cloud server store them in the database of Openstack, and then achieve the calculation of ciphertexts according to the computing needs of users, and store it in the database for users to fetch. The users can fetch it in the database via the SQL language and decrypt the ciphertext to obtain the results which is corresponding to the calculation of the plaintexts.