Changho Seo

New efficient bit-parallel polynomial basis multiplier for special pentanomials

We present a bit-parallel polynomial basis multiplier based on a new divide-and-conquer approach using squaring. In particular, we apply the proposed approach to special types of irreducible pentanomials called as types I and II pentanomials, and induce explicit formulae and complexities of the proposed multiplier for these types of pentanomials. As a result, the proposed multiplier for type I pentanomials has almost the same time complexity, but about 25% reduced space complexity compared with the best known results in the literature. For type II pentanomials, we obtain the multiplier which has the lowest time complexity and about 25% reduced space complexity than the best known polynomial basis multipliers.

Symmetric searchable encryption with efficient range query using multi-layered linked chains

Searchable encryption is an encryption system which provides confidentiality of stored documents and usability of document search at the same time. Remote cloud storage is the most typical application for searchable encryption. By applying searchable encryption, inside attacks can be prevented fundamentally. Designing searchable encryption which supports various queries—for example, range query, conjunctive keyword query, etc.—is also important for convenience. In this paper, we focus on range query problem. Up to now, only a few results have been proposed, in which the main functions are constructed using public key cryptosystems. Therefore, the amount of computations for encryption and search is large. Furthermore, search time depends on the size of the entire database. We propose a new searchable encryption protocol which is based on a symmetric key encryption and linked chain structure instead of public key-based techniques. The main contribution of the protocol is reducing the computation cost for search remarkably. In reality, the amount of computations depends on the number of documents that are matched to a query instead of the size of the entire database.

Comments on “Multiway Splitting Method for Toeplitz Matrix Vector Product”

We propose block decompositions for the Toeplitz matrix-vector product (TMVP) using the k-way splitting method presented in the above paper. As a result, we show that the space complexity for TMVP can be improved.

New Block Recombination for Subquadratic Space Complexity Polynomial Multiplication Based on Overlap-Free Approach

In this paper, we present new parallel polynomial multiplication formulas which result in subquadratic space complexity. The schemes are based on a recently proposed block recombination of polynomial multiplication formula. The proposed two-way, three-way, and four-way split polynomial multiplication formulas achieve the smallest space complexities. Moreover, by providing area-time tradeoff method, the proposed formulas enable one to choose a parallel formula for polynomial multiplication which is suited for a design environment.

Parallel Implementation of LSH Using SSE and AVX

Hash function is a cryptographic primitive which conduct authentication, signature and data integrity. Recently, Wang et al. found collision of standard hash function such as MD5, SHA-1. For that reason, National Security Research Institute in Korea suggests a secure structure and efficient hash function, LSH. LSH consists of three steps, initialization, compression, finalization and computes hash value using addition in modulo , bit-wise substitution, word-wise substitution and bit-wise XOR. These operation is parallelizable because each step is independently conducted at the same time. In this paper, we analyse LSH structure and implement it over SIMD-SSE, AVX and demonstrate the superiority of LSH.

An Implementation of an SHA-3 Hash Function Validation Program and Hash Algorithm on 16bit-UICC

A hash function is an essential cryptographic algorithm primitive that is used to provide integrity to many applications such as message authentication codes and digital signatures. In this paper, we introduce a concept and test method for a Cryptographic Algorithm Validation Program (CAVP). Also, we design an SHA-3 CAVP program and implement an SHA-3 algorithm in 16bit-UICC. Finally, we compare the efficiency of SHA-3 with SHA-2 and evaluate the exellence of the SHA-3 algorithm.

Comments on “On the Polynomial Multiplication in Chebyshev Form”

In the above paper, Akleylek proposed an efficient multiplication algorithm for polynomials in Chebyshev form. In this comment, we show that a recombination of the above proposed algorithm induces more efficient algorithm for the multiplications of polynomials in Chebyshev form.

Efficient multiplier based on hybrid approach for Toeplitz matrix-vector product ☆

Abstract We propose a hybrid approach for a Toeplitz matrix–vector product (TMVP) of size k ⋅ 2 i 3 j , where k ≥ 1 and i , j ≥ 0 . It is possible to make trade-offs between time and space complexities for a TMVP by choosing values k, i, and j properly. We show that the multiplier based on the proposed hybrid TMVP approach has lower space as well as time complexities than other subquadratic space complexity multipliers for five fields recommended by NIST. Moreover, for those five fields, the space complexities of the proposed multiplier are reduced by a minimum 59 % and a maximum 77 % compared with quadratic space complexity multiplier.

Encrypted Data Deduplication Using Key Issuing Server

Data deduplication is an important technique for cloud storage savings. These techniques are especially important for encrypted data because data deduplication over plaintext is basically vulnerable for data confidentiality. We examined encrypted data deduplication with the aid of a key issuing server and compared Convergent Encryption with a technique created by M.Bellare et al. In addition, we implemented this technique over not only Dropbox but also an open cloud storage service, Openstack Swift. We measured the performance for this technique over Dropbox and Openstack Swift. According to our results, we verified that the encrypted data deduplication technique with the aid of a key issuing server is a feasible and versatile method.

Analysis of the present state and Improvement of the Institute of Information Security Education for the Gifted

Today, as a daily routine such as administration/finance is operated under information system and various cyber crime against national, public, and private institutions happen, demand for information security manpower is increasing. Hence, Ministry of Education has formed an Institute of Information Security Education for the Gifted to early discover talent in the field of information security and train professional personnel with specialty and ethics in 4 universities of country in 2014. But the nascent Institute of Information Security Education for the Gifted lack systematic analyses compared to Institute of Mathematics and Science Education for the Gifted that has existed from a long time ago. In this paper, we analyze the state of the Institute of Information Security Education for the Gifted in three parts: operation, selection, education and suggest an improvement to build a practical program for effective operations and education.