另一種關連式資料庫加解密法

Abstract

本文提出一種新的資料庫加密法。其主旨乃是將置換、重排、 區塊加密等方法整合，以達到關連式資料庫之安全加解密的功能。本法之 特點為針對不同的記錄，使用不同的密匙做加密，因而提高了明文攻擊的 困難度。此外，本文利用簡單之運算達成資料安全的目的，節省作業之時 間，以確保加解密效率。透過對密文資料量的事前掌控，避免明文擴充之 弊。 簡而言之，在安全、效率及空間三方面，本法皆有一定程度之滿足 。

In this paper, we propose a new encryption method for the relational databases based upon substitution, permutation and block cipher. Each block is encrypted by different keys and that makes known-plaintext attack more difficult. All the operations we need are XOR and permutation. The space which a encrypted record needs is almost the same as a plaintext record. Our scheme not only encrypts the data records for security but also avoids plaintext-extension and does operations efficiently.