Earticle

이 연구는 전자계약에 대한 이론적 배경을 정리하고, 국토교통부 부동산거래 전자계 약시스템에서 적용된 기술과 특징을 고찰하였다. 실제 전자계약서의 디지털 서명 구간 별로 내용을 변경하고 나타나는 무결성 여부를 검증했다. 연구 결과, 부동산 전자계약서는 디지털 서명 유효성 확인기능을 가진 PDF 문서뷰 어를 이용하여 무결성 검증이 가능하고, 인터넷 접속과 제 3자 증명 없이 무결성을 확인 할 수 있었다. 결과적으로, 계약서 소지자 본인 및 전자계약서를 제시받은 금융기관 및 공공기관에서 신뢰하고 이용할 수 있다는 것을 확인했다. 단, 디지털 서명검증 기능이 없는 PDF 문서뷰어를 이용하는 경우 제2종 오류 유형로 인한 위험이 발생할 수 있다.

This study puts together the theoretical background of the electronic contract and reviews the technology and features applied in the electronic contract system for real estate transactions of the Ministry of Land, Infrastructure and Transport. In order to verify the integrity of the actual electronic contract, modification of the code of the electronic contract file was conducted for each digital signature section and the results were reviewed. This study shows that the integrity of the electronic contract of real estate transaction can be verified by using the PDF viewer which conforms to the international standard of digital signature validation, and the integrity of the electronic contract can be verified without Internet access and third party proof. As a result, it is confirmed that the holder of the electronic contract and the financial institution and public institution that have presented the electronic contract can trust and use electronic contract. However, if a user uses a PDF viewer without a digital signature verification function, the type 2 error risk may occur.

최근 들어, 스마트 단말에서 지불, 인터넷 뱅킹 등 금융업무와 관련된 중요한 정보들을 다루는 경우가 많 아졌다. 또한 스마트 단말의 실행환경이 공개 소프트웨어 환경 위주로 발전하면서, 사용자들이 임의의 응용소프트웨 어를 다운받아 사용하는 것이 용이하게 됨에 따라, 스마트 단말이 보안적 측면에서 취약하게 되었다. 본 논문에서는 하드웨어 기반의 스마트 단말 보안 기술의 특징을 알아본다. 또한, 본 논문에서는 스마트 단말 에서 실행되는 응용 프로그램을 위한 MTM 하드웨어기반의 안전한 스마트 단말 실행환경에 대한 구현방법을 제안한다. 기존의 MTM 이 모바일 장치에 대한 신뢰의 근원 기능만을 제공한 반면, 본 논문에서 제시하는 MTM 기반 모바일 보안 환경은 모바 일 장치에서 실행되는 응용프로그램이 필요로 하는 다양한 보안 기능을 제공할 수 있다. 향후, 보안 하드웨어와 연 동이 가능한 IoT 기기와 게이트웨이 보안 기술, 그리고 보안 하드웨어를 활용하여 다양한 IoT 기기에 적용하여 신뢰 성과 보안성을 확보하는 방안에 대한 연구를 진행할 예정이다.

Recently, the frequency of dealing important information regarding financial services like paying through smart device or internet banking on smart device has been increasing. Also, with the development of smart device execution environment towards open software environment, it became easier for users to download and use random application software, and its security aspect appears to be weakening. This study inspects features of hardware-based smart device security technology. Furthermore, this study proposes a realization method in MTM hardware-based secure smart device execution environment for an application software that runs in smart devices. While existing MTM provides the root of trust function only for the mobile device, the MTM-based mobile security environment technology proposed in this paper can provide numerous security functions that application program needs in mobile device. The further researches on IoT devices that are compatible with security hardware, gateway security technology and methods that secure reliability and security applicable to varied IoT devices by advancing security hardware are the next plan to proceed.

Many organizations today use patch management systems to uniformly manage software vulnerabilities. However, the patch management system does not guarantee the integrity of the patch in the process of providing the patch to the client. In this paper, we propose a method to guarantee patch integrity through dual electronic signatures. The dual electronic signatures are performed by the primary distribution server with the first digital signature and the secondary distribution server with the second digital signature. The dual electronic signature ensures ensure that there is no forgery or falsification in the patch transmission process, so that the client can verify that the patch provided is a normal patch. The dual electronic signatures can enhance the security of the patch management system, providing a secure environment for clients.

Software bills of materials (SBOMs) support supply chain transparency, but they do not prove that a delivered SBOM reproducibly corresponds to its software artifact. Existing signing and provenance mechanisms protect integrity and traceability, yet lack consumer-side reproducible verification. We propose an SBOM integrity verification framework combining procedure disclosure, consumer-side reproduction, authority-generated reference evidence, and digest comparison. A trusted authority records a reference digest, and consumers compare it with locally reproduced and delivered SBOM digests. Experiments on 100 real-world container images show detection of artifact tampering, SBOM substitution, distribution modification, and adaptive tampering beyond signature-based approaches.

자동차의 센서, 신호 등 데이터를 수집·처리하는 ECU 데이터가 공격에 의해 조작되면 운전자에게 피해를 줄 수 있 다. 본 논문에서는 블록체인을 이용하여 자동차 ECU 데이터의 무결성을 검증하는 시스템을 제안한다. 자동차와 서버는 세션 키를 이용해 데이터를 암호화하여 송·수신하기 때문에 통신 과정에서 신뢰성을 보장한다. 서버는 해시 함수를 이용해 전송받 은 데이터의 무결성을 검증한 후, 데이터에 이상이 없으면 블록체인과 off-chain인 분산저장소에 저장한다. ECU 데이터 해 시값은 블록체인에 저장하여 변조할 수 없으며, 원본 ECU 데이터는 분산저장소에 저장한다. 해당 검증 시스템을 이용해 ECU 데이터에 대한 공격 및 변조를 사용자가 검증할 수 있으며, 악의적인 사용자가 ECU 데이터에 접근하여 데이터 변조 시 무결성 검증을 수행할 수 있다. 보험, 자동차 수리, 거래 및 판매 등의 상황에서 사용자의 필요에 따라 사용할 수 있다. 향후 연구로는 실시간 데이터 무결성 검증을 위한 효율적인 시스템 구축이 필요하다.

If ECU data, which is responsible for collecting and processing data such as sensors and signals of automobiles, is manipulated by an attack, it can cause damage to the driver. In this paper, we propose a system that verifies the integrity of automotive ECU data using blockchain. Since the car and the server encrypt data using the session key to transmit and receive data, reliability is ensured in the communication process. The server verifies the integrity of the transmitted data using a hash function, and if there is no problem in the data, it is stored in the blockchain and off-chain distributed storage. The ECU data hash value is stored in the blockchain and cannot be tampered with, and the original ECU data is stored in a distributed storage. Using the verification system, users can verify attacks and tampering with ECU data, and malicious users can access ECU data and perform integrity verification when data is tampered with. It can be used according to the user's needs in situations such as insurance, car repair, trading and sales. For future research, it is necessary to establish an efficient system for real-time data integrity verification.

최근 네트워크 및 하드웨어 기술이 발전하여 블록체인 기술과 보안을 융합하는 연구가 활발히 진행되고 여러 네트워크 기술에 적용되고 있다. 기존의 블록체인을 활용한 기술을 분석하고 제한된 환경에서 비공개 블록체인을 활용 한 파일의 무결성을 검증하는 모델을 제안한다. 제안하는 모델은 비공개 블록체인 플랫폼인 하이퍼레저 패브릭의 체인 코드로 작성하고 비공개 블록체인 통합 관리 플랫폼인 하이퍼레저 익스플로러를 통해 파일의 무결성 검증을 확인할 수 있 다. 제안한 모델의 성능을 개발자 관점과 사용자 관점에서 분석했다. 블록체인 플랫폼을 실행하기 위한 다양한 모듈의 버전에 따른 호환성 문제가 존재하고 체인코드 상태와 그룹 등 제한된 요소만 확인이 가능하다는 결과를 얻었다.

Recent advances in network and hardware technologies have led to active research and multiple network technologies that fuse blockchain technologies with security. We propose a system model that analyzes technologies using existing blockchain and verifies the integrity of files using private blockchain in a limited environment. The proposed model can be written as a chain code of Hyperleisure Fabric, a private blockchain platform, and verified for integrity of files through Hyperleisure Explorer, a private blockchain integrated management platform. The system performance of the proposed model was analyzed from a developer perspective and from a user perspective. As a result of the analysis, there are compatibility problems according to the version of various modules to run the blockchain platform, and only limited elements such as chain code status and groups can be checked.

디지털 영상매체의 특성상 데이터 접근 용이성에 따른 복제 및 변형, 손상, 휘발성 등의 위험이 발생하고 있어 안전하게 보존하는 방법에 대한 연구가 필요하다. 단방향암호화 해시함수를 활용하여 뉴미디어 영상작품의 무결성검증방법 적용연구를 진행하였으며, 이를 바탕으로 영상 장기 보존의 기초자료를 구축하고자 하였다. 해시함수는 임의의 길이를 가진 데이터를 입력받아 고정된 길이의 값, 즉 해시값을 생성하는 함수를 의미하며 데이터에 따라 해시값이 달라지는 특징이 있다. 이를 활용하여 초기값과 현재의 값을 비교하여 데이터 생성 이후 위변조 없이 그대로의 상태를 유지 하고 있는 무결성을 판단하는 데 활용할 수 있다. Microsoft가 개발한 기본 프로그램인 Windows Powershell을 이용하여 해시값을 생성하였으며 해시함수로 SHA(Secure Hash Algorithm)-256을 사용 하였다. 해시함수 적용 여부를 판단하기 위해 실험을 진행하였으며, 실험결과, 변형 및 손상유형에 따른 해시값 변화, 해시 생성시간, 다수의 파일 해시값 생성 결과를 통해 작품 적용 가능성을 확인할 수 있었고 빠르게 손상 여부 판단이 가능하였다. 추후 주기적인 검사를 통해 해시값을 비교하면 무결성검증 뿐만 아니라 파일 포맷 또는 저장매체의 상태변화까지 확인할 수 있을 것으로 기대된다.

Due to the characteristic of digital video media, there are risk of copying, deformation, damage, and volatility due to ease of access to data, so research on how to safely preserve it is necessary. A study was conducted to apply integrity verification method of new media video using one-way encryption hash function, and based on this, basic data for long-term image preservation were established. The hash function refers to a function that generates data with any length of a fixed length, and the hash value of a fixed length, and the hash value is different depending on data. This can be used to compare the initial value with the current value to determine the integrity of maintaining the state without forgery and alteration after data generation. The hash value was generated using Windows Powershell, a basic program developed by Microsoft, and SHA (Secure Hash Algorithm)-256, was used as a hash function. An experiment was conducted to determine whether the hash function was applied. As a result of the experiment, the applicability of the work was confirmed through hash value changes according to deformation and damage type, hash generation time, and multiple file hash value generation results, and it was possible to quickly determine whether or not there was damage. By comparing hash values through periodic inspection in the future, it is expected that not only integrity verification but also changes in the status of the file format or storage medium can be confirmed.

2002년에 제정된 전자정부법에 따라 행정업무 환경이 전자문서 중심으로 전환되면서 전자문서 관리를 위한 1만 6,228개 행정정보시스템과 1만9,533개 데이터베이스가 설치되었다. 2020년에는 공공기록물 관리에 관한 시행령 개정 및 행정정보 데이터세트 기록관리 기준에 관한 공공표준을 제정하여 행정정보 데이터세트에 대한 기록관리를 본격적으로 추진하였다. 이로써 전자문서로 한정되어 있던 기록관리 범위를 데이터세트까지 포괄하게 되었다. 전자 문서는 파일에 보관되므로 파일 단위의 기록관리가 이루어졌지만 데이터세트는 실행 중인 DBMS(관계형, NoSQL 등)에서 관리되므로 파일 단위로 무결성을 검증하는 기존 방식이 적용되기 어렵다. 그래서 본 연구에서는 블록체인 을 기반으로 관계형 그리고 NoSQL 데이터베이스에서 관리되고 있는 데이터세트에 대해서 무결성을 검증할 수 있 는 방안을 제시한다. 실제 프로토타입 구현을 통해 제안한 방안이 DBMS에 관리되는 데이터세트에 대해서도 효과 적으로 무결성을 검증할 수 있음을 증명하였다. 본 논문의 연구결과는 향후 대용량의 전자기록이 생산되는 현재의 기록관리 분야에서 무결성을 검증할 수 있는 기술 기반을 제공할 수 있을 것으로 기대된다.

According to the E-Government Act enacted in 2002, as the government work environment shifted to electronic documents, 16,228 administrative information systems and 19,533 databases were installed to manage electronic documents. In 2020, public records management for administrative information datasets was promoted in earnest by amending the enforcement ordinance on public records management and enacting public standards for administrative information dataset records management standards. The records management system, which was limited to electronic documents, has now been encompassed to the dataset. Since each electronic document is stored in a file, datasets are managed in the currently running DBMS(RDB, NoSQL, etc.), unlike records management in units of files, it is difficult to introduce the existing method of verifying the integrity of each file to datasets. Therefore, in this study, we propose a method to verify the integrity of datasets managed in relational and NoSQL databases based on blockchain. By implementing a prototype, we proved that the proposed method can effectively verify the integrity of datasets in the DBMS. The research results of this paper are expected to provide a technological base to verify the integrity of the current records management field where large-capacity electronic records are produced in the future.

Databases play an important role today in every modern organization, verifying their integrity is needed. Watermarking can be used to protect the integrity of database. In this paper, we present a secure fragile embedding watermark technique to verify the authenticity of an outsourced numeric relational database. Our technique treats the watermark embedding as an optimization problem by securely inserting a single watermark bit in individual database partition and the optimal threshold is computed for watermark detection. The approach partitions the database in different groups of square matrix and modifies the database while preserving the field values usability constraints. The database group determinant value is used to compute the position of field to be marked. Furthermore, we evaluated our scheme on a real case study and results show its effectiveness. The proposed scheme can detect and localize the malicious modifications made to the database. The proposed technique is highly resilient to common attacks and it overcomes some limitations of previous approaches on fragile watermarking.

Due to advancement in cloud computing technology, the research on the outsourced database has been spotlighted. In database outsourcing, because the service provider might be untrusted or compromised, two issues of data security emerge: data confidentiality and data integrity. Many data transformation schemes were widely studied for preserving data confidentiality, but they are vulnerable to data leakage problem because they do not consider data distribution when encrypting original data. Meanwhile, several query authentication schemes were proposed to verity data integrity, but they suffer from transmission overhead of verification data. Motivated by these problems, we propose a privacy-aware query authentication scheme which guarantees the data confidentiality and the query result integrity of sensitive data. To solve the original data leakage problem, our clustering-based data transformation scheme is designed to select anchors based on data distribution. To verify the query result, we propose a query result authentication index that stores an encrypted signature for each anchor, which is a concatenated hash digest of cluster data. A user compares the verification information with the cluster signatures stored in the verification index. Through performance evaluation, we show that our method outperforms the existing method in terms of query processing time and verification data size.

There exist two key problems about data aggregation that should be thoroughly explored - algorithm design in networking layer, and algorithm design in application layer. Those two problems should be subtlety tackled in termers of high efficiency and robustness. Therefore, the former one requires the survivability and highly reliable design at networking layer, the latter one usually asks for high efficiency and robustness at application layer. Moreover, the optimization of algorithms is also considered for further enhancement. The integrity check is a key requirement for optimization. The context-aware and cross-layer design is applied in the optimization. A dynamic fragment odd-even parity checking code is proposed, and a context-aware aggregative integrity check code is proposed.

A self-adaption fault-tolerant mechanism based on access frequency (SFMAF) is proposed for the cloud storage platform, wherein this mechanism aims at adopting the approximate LRU (Least Recently Used) algorithm to maintain a file access frequency table in order to self-adaptively adjust the fault-tolerant mode. Specifically, the replica redundancy mechanism is adopted in SFMAF for the frequently accessed files and RS (Reed-Solomon) erasure code tolerant mechanism is adopted in SFMAF for the rarely accessed files. The experiment result shows: compared with the replica redundancy mechanism, SFMAF can reduce the transmission flow of the internal system data at the cost of increasing CPU and memory usage rates in an acceptable range, namely: the system storage space is reduced.

MapReduce, a large-scale data processing paradigm, is gaining popularity. However, like other distributed computing frameworks, MapReduce suffers from the integrity assurance vulnerability: malicious workers in the MapReduce cluster could tamper with its computation result and thereby render the overall computation result inaccurate. Existing solutions are effective in defeating the malicious behavior of non-collusive workers, but are less effective in detecting collusive workers. In this paper, we propose the Verification-based Integrity Assurance Framework (VIAF). By using task replication and probabilistic result verification, VIAF can detect both non-collusive and collusive workers, even if the malicious workers dominate the environment. We have implemented VIAF on Hadoop, an open source MapReduce implementation. Our theoretical analysis and experimental result show that VIAF can achieve high job accuracy while imposing moderate performance overhead.

Cloud storage offers clients great convenience to relieve them from heavy burden of storage and management, so an increasing number of clients choose to outsource their data to remote cloud providers. However, for clients, this entails a sacrifice of actual control of these files. Remote servers may suffer from disk failure for uncertain reasons or even delete rarely accessed data to sell these storages to other clients. Therefore, there’s a great necessity for clients to make sure that their data are well stored in remote servers. Numbers of remote integrity checking (RIC) schemes are proposed to solve issues above, including following up work Provable Data Possession (PDP) and Proofs of Retrievability (PoR), which can be applied in cloud auditing. This paper presents state-of-the-art RIC schemes and makes a classification from the perspective of whether they support dynamic verifications, i.e., whether they can still be used to make verifications after clients modify, insert or delete files. In static verification schemes, we delve into the mechanisms and techniques used for integrity checking. For dynamic ones, we discuss the authentication structures that support dynamic operations. We also present several remarks to guide readers to a wide vision of data checking as conclusions and future work.

Interconnect lines with inter-layer vias are experimentally characterized by using high-frequency S-parameter measurements. Test patterns are designed and fabricated using a package process. Then they are measured using Vector Network Analyzer (VNA) up to 25 GHz. Modeling a via as a circuit, its model parameters are determined. It is shown that the circuit model has excellent agreement with the measured S-parameters. The signal integrity of the lines with inter-layer vias is evaluated by using the developed circuit model. Thereby, it is shown that via may have a substantially deteriorative effect on the signal integrity of high-speed integrated circuits.

A new efficient analytical eye-diagram determination technique for coupled interconnect lines is presented. Two coupled lines are decoupled into isolated eigen modes; bit blocks for coupled lines, which are defined as a block of consecutive bits, are then represented with decoupled modes. The crosstalk effects within the bit blocks are taken into account. Thereby, the crucial input bit patterns for the worst case eye-diagram determination are modeled mathematically, including inter-symbol interference (ISI). The proposed technique shows excellent agreement with the SPICE-based simulation. Furthermore, it is very computation-time-efficient in the order of magnitude, compared with the SPICE simulation, which requires numerous pseudo-random bit sequence (PRBS) input signals.

함정 전투관리체계는 다양한 센서, 무장 장비들이 연동 노드를 통해 연결되며 체계내 노드간 효율적인 통신을 위해 DDS(Data Distribution Service) 통신을 활용한다. DDS를 사용하기 위해 체계내 응용소프트웨어 사이에는 DDS토픽을 기본으로 하는 PUB/SUB(Publication/Subscribe)방식으로 통신한다. 이 PUB/SUB방식으로 통신하는 DDS 메시지 구조가 일치하지 않으면 송수신 응용소프트웨어에서 잘못된 명령처리 및 정보전달 등 문제가 발생한다. 이를 개선하기 위해 본 논문에서는 해시트리를 활용한 DDS 메시지 구조 무결성 검증 방법을 제안한다. 제안하는 방법의 전투관리체계에 적용가능성을 확인하기 위해, 제안하는 방법의 메시지 구조 무결성 검증률을 측정하고 전투관리체계의 운용과 개발과정에 미치는 영향을 확인하기 위해 전투관리체계 초기화 시간 비교, 메시지 해시트리의 생성시간 측정을 하였다. 이 시험을 통해 본 논문에서 제안하는 체계 안정성을 위한 메시지 구조 검증 방법이 함정 전투관리체계에 적용 가능함을 확인하였다.

Naval CMS(Combat Management System) is linked to various sensors and weapon equipment and use DDS(Data Distribution Service) for efficient data communication between ICU(Interface Control Unit) Node and IPN(Information Processing Node). In order to use DDS, software in the system communicates in an PUB/SUB(Publication/Subscribe) based on DDS topic. If the DDS messages structure in this PUB/SUB method does not match, problems such as incorrect command processing and wrong information delivery occur in sending and receiving application software. To improve this, this paper proposes a DDS message structure integrity verification method. To improve this, this paper proposes a DDS message structure integrity verification method using a hash tree. To verify the applicability of the proposed method to Naval CMS, the message integrity verification rate of the proposed method was measured, and the integrity verification method was applied to CMS and the initialization time of the existing combat management system was compared and the hash tree generation time of the message structures was measured to understand the effect on the operation and development process of CMS. Through this test, It was confirmed that the message structure verification method for system stability proposed in this paper can be applied to the Naval CMS.

The Optical Wide-field patroL-Network (OWL-Net) is a global optical network for Space Situational Awareness in Korea. The primary operational goal of the OWL-Net is to track Low Earth Orbit (LEO) satellites operated by Korea and to monitor the Geostationary Earth Orbit (GEO) region near the Korean peninsula. To obtain dense measurements on LEO tracking, the chopper system was adopted in the OWL-Net's back-end system. Dozens of angle-only measurements can be obtained for a single shot with the observation mode for LEO tracking. In previous work, the reduction process of the LEO tracking data was presented, along with the mechanical specification of the back-end system of the OWL-Net. In this research, we describe an integrity assessment method of time-position matching and verification of results from real observations of LEO satellites. The change rate of the angle of each streak in the shot was checked to assess the results of the matching process. The time error due to the chopper rotation motion was corrected after re-matching of time and position. The corrected measurements were compared with the simulated observation data, which were taken from the Consolidated Prediction File from the International Laser Ranging Service. The comparison results are presented in the In-track and Cross-track frame.