학술논문

Substring Searchable Symmetric Encryption Based on an Improved DAWG
Document Type
Journal Article
Source
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences. 2022, E105.A(12):1578
Subject
directed acyclic word graph
searchable symmetric encryption
string matching
Language
English
ISSN
0916-8508
1745-1337
Abstract
A searchable symmetric encryption (SSE) scheme is a method that searches encrypted data without decrypting it. In this paper, we address the substring search problem such that for a set D of documents and a pattern p, we find all occurrences of p in D. Here, a document and a pattern are defined as a string. A directed acyclic word graph (DAWG), which is a deterministic finite automaton, is known for solving a substring search problem on a plaintext. We improve a DAWG so that all transitions of a DAWG have distinct symbols. Besides, we present a space-efficient and secure substring SSE scheme using an improved DAWG. The proposed substring SSE scheme consists of an index with a simple structure, and the size is O(n) for the total size n of documents.