具相等性驗證的全同態加密

Abstract

全同態加密（Fully Homomorphic Encryption, FHE）支援在密文空間中進行運算。然而，全同態加密並不支援條件控制（conditioal control）。近年提出的相等性驗證（equality test）也因進行同態運算時其密文會發生改變而不適用於全同態加密。在本研究中，我們提出了一種具相等性驗證的全同態加密系統——FHEET。此系統允許我們在全同態加密上執行相等性驗證，進而能在全同態加密中使用條件控制。Fully homomorphic encryption (FHE) enables operation over ciphertext space. However, FHE is not capable for conditional control. Recent equality test schemes are not applicable for FHE due to the same reason, its ciphertext changes when homomorphic operation. In this work, we propose a fully homomorphic encryption with equality test scheme, FHEET. This scheme allows us to do equality test over FHE and makes conditional control capable for FHE.