• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.5
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• pp.581-591
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• 2016

RFID(Radio Frequency IDentification) is a key technology in ubiquitous computing and is expected to be employed in more fields in the near future. Nevertheless, the RFID system is vulnerable to attacks by eavesdropping or altering of the messages transmitted in wireless channels. In 2013, Oh et al. proposed a mutual authentication protocol between a tag and a reader in RFID systems. Their protocol is designed to resist location tracking for privacy protection. However, all tags and readers use only one network-wide key in their protocol and tags are usually vulnerable to physical attacks. We found that their protocol is still vulnerable to tag/reader impersonation attacks and location tracking if an attacker obtains the network-wide key from a tag. In this paper, we propose a security improved authentication protocol for privacy protection in RFID systems. In addition, we demonstrate that the proposed scheme is efficient in terms of computation and communication costs.

• The KIPS Transactions:PartC
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• v.13C no.2 s.105
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• pp.195-202
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• 2006

For applying sensor networking technology for our daily life, security service is essential, and pairwise key establishment is the key point for security. In this paper, we propose fairwise key establishment mechanism for secure coumunication in sensor networks. In the mechanism, we cluster the network field before deployment and predistribute key materials to normal sensor nodes and clusterheads. For clusterheads, more key materials are predistributed, and after deployment, sensor nodes which need to establish pairwise keys with other sensor nodes in different clusters make request for related key materials to their own clusterheads. Our proposal reduces the memory requirements for normal sensor nodes by distributing more information to clusterheads, and it raises the security level and resilience against node captures. In addition, it guarantees perfect pairwise key establishments for every pair of neighboring nodes and provides efficient and secure sensor communications.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1594-1617
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• 2018

In this paper, we consider a spectrum access scenario which consists of two groups of users, namely Primary Users (PUs) and Secondary Users (SUs) in Cooperative Cognitive Radio Networks (CCRNs). SUs cooperatively relay PUs messages based on Amplify-and-Forward (AF) and Decode-and-Forward (DF) cooperative techniques, in exchange for accessing some of the spectrum for their secondary communications. From the literatures, we found that the Conventional Distributed Algorithm (CDA) and Pragmatic Distributed Algorithm (PDA) aim to maximize the PU sum-rate resulting in a lower sum-rate for the SU. In this contribution, we have investigated a suit of distributed matching algorithms. More specifically, we investigated SU-based CDA (CDA-SU) and SU-based PDA (PDA-SU) that maximize the SU sum-rate. We have also proposed the All User-based PDA (PDA-ALL), for maximizing the sum-rates of both PU and SU groups. A comparative study of CDA, PDA, CDA-SU, PDA-SU and PDA-ALL is conducted, and the strength of each scheme is highlighted. Different schemes may be suitable for different applications. All schemes are investigated under the idealistic scenario involving perfect coding and perfect modulation, as well as under practical scenario involving actual coding and actual modulation. Explicitly, our practical scenario considers the adaptive coded modulation based DF schemes for transmission flexibility and efficiency. More specifically, we have considered the Self-Concatenated Convolutional Code (SECCC), which exhibits low complexity, since it invokes only a single encoder and a single decoder. Furthermore, puncturing has been employed for enhancing the bandwidth efficiency of SECCC. As another enhancement, physical layer security has been applied to our system by introducing a unique Advanced Encryption Standard (AES) based puncturing to our SECCC scheme.

• ETRI Journal
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• v.44 no.6
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• pp.903-914
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• 2022

Mobile and telecommunication networking uses temporary and random identifiers (IDs) to protect user privacy. For greater intelligence and security o the communications between the core network and the mobile user, we design and build a dynamic randomization scheme for the temporary IDs for mobile networking, including 5G and 6G. Our work for ID randomization (ID-RZ) advances the existing state-of-the-art ID re-allocation approach in 5G in the following ways. First, ID-RZ for ID updates is based on computing, as opposed to incurring networking for the re-allocation-based updates, and is designed for lightweight and low-latency mobile systems. Second, ID-RZ changes IDs proactively (as opposed to updating based on explicit networking event triggers) and provides stronger security (by increasing the randomness and frequency of ID updates). We build on the standard cryptographic primitives for security (e.g., hash) and implement our dynamic randomization scheme in the 5G networking protocol to validate its design purposes, which include time efficiency (two to four orders of magnitude quicker than the re-allocation approach) and appropriateness for mobile applications.

• Journal of Communications and Networks
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• v.13 no.2
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• pp.175-186
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• 2011

The proliferation of advanced technologies has been altering our lifestyle and social interactions-the next frontier is the digital home. Although the future of smart homes is promising, many technical challenges must be addressed to achieve convenience and security. In this paper, we delineate the unique combination of security challenges specifically for access control and consider the challenges of how to simply and securely assign access control policies to visitors for home devices and resources. We present a set of intuitive access control policies and suggest four access control settings based on our in-person interview results. Furthermore, we propose the automated Clairvoyant access right assignment (CARA) mechanism that utilizes home owners' social relationship to automatically deduce to which class a visitor belongs. The combination of CARA and the suggested mapping provides a promising first step for home policy assignment such that nonexpert home owners can let visitors use their home network with confidence. We anticipate that future research can build on our proposed mechanisms to provide confidence to non-expert home owners for letting visitors use their home network.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.3
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• pp.313-323
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• 2020

With the development of smart grid technologies, a user can use the secure and reliable power services in smart gird environments. However, the users are not secure against various potential attacks because the smart gird services are provided through the public channel. Therefore, a secure and lightweight authentication and key agreement scheme has become a very important security issue in smart grid in order to guarantee user's privacy. In 2019, Zhang et al. proposed a lightweight authentication scheme for smart gird communications. In this paper, we demonstrate that Zhang et al.'s scheme is vulnerable to impersonation and session key disclosure attacks, and then we propose a secure authentication and key agreement scheme for smart grid environments without tamper-resistant devices. Moreover, we perform the informal security and the BAN logic analysis to prove that our scheme is secure various attacks and provides secure mutual authentication, respectively. We also perform the performance analysis compared with related schemes. Therefore, the proposed scheme is efficiently applicable to practical smart gird environments.

• International Journal of Computer Science & Network Security
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• v.23 no.5
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• pp.13-20
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• 2023

In connected vehicles, drivers are exposed to attacks when they communicate with unauthenticated peers. This occurs when a vehicle relies on outdated information resulting in interactions with vehicles that have expired or revoked certificates claiming to be legitimate nodes. Vehicles must frequently receive or query an updated revoked certificate list to avoid communicating with suspicious vehicles to protect themselves. In this paper, we propose a scheme that works on a highway divided into clusters and managed by roadside units (RSUs) to ensure authenticity and preserve hidden identities of vehicles. The proposed scheme includes four main components each of which plays a major role. In the top hierarchy, we have the authority that is responsible for issuing long-term certificates and managing and controlling all descending intermediate authorities, which cover specific regions (e.g., RSUs) and provide vehicles with short-term pseudonyms certificates to hide their identity and avoid traceability. Every certificate-related operation is recorded in a blockchain storage to ensure integrity and transparency. To regulate communication among nodes, security managers were introduced to enable authorization and access right during communications. Together, these components provide vehicles with an immediately revoked certificate list through RSUs, which are provided with publish/subscribe brokers that enable a controlled messaging infrastructure. We validate our work in a simulated smart highway environment comprising interconnected RSUs to demonstrate our technique's effectiveness.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.215-224
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• 2010

A container security device (CSD) monitors intrusions through the cargo door; it is a reduced function device that uses IEEE 802.15.4 with a beacon mode. However, in the beacon mode, the CSD consumes too much battery power in periodical idle listening and sensing trials. Moreover, the CSD cannot send the message to the CSD reader actively, and it makes big latency problem. Therefore, we propose a low-power CSD to reduce the unnecessary power consumption. The proposed CSD follows the requirements of the U.S. Department of Homeland Security, and reduces battery consumption through a power-efficient hardware design, a night-watch mechanism for low-power operation and low-power sensing to reduce unnecessary monitoring. And the CSD sends alert message to the CSD reader. Simulation results show that our CSD reduces battery consumption by over 70% through the night-watch mechanism and by approximately 80% through the low-power sensing. And the CSD can send the alert message to the remote CSD reader by over 94%.

• Journal of Distribution Science
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• v.14 no.11
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• pp.37-47
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• 2016

Purpose - Many countries nowadays look at cloud computing as an opportunity because it holds great advantages for governments. Public sector in Yemen still uses traditional computing. This study tends to explore the factors that would affect cloud computing adoption in government organizations in Yemen. Research design, data and methodology - We used a combination of DOI theory and TOE framework with some changes to suit the context of government organizations. Eight hypotheses were proposed with a questionnaire developed and sent to people in Yemen. 118 responses were collected to assess the hypotheses. Results - Results indicate that Yemen lacks some prerequisites of cloud technology in terms of technological readiness and regulations. The factors: relative advantage, compatibility, security concern, perception of benefits and government support were accepted. Perception of benefits, in particular, is found to affect the decision of adoption. Security concern also showed a direct and indirect influence on cloud adoption in the government. Respondents consider security a key issues of the technology. The factors: complexity, technology readiness and regulatory support were rejected. Conclusions - Based on all analysis results, this study proposed some steps toward adopting cloud computing in Yemen.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2C
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• pp.208-218
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• 2008

We are sure that RFID system should be a widely used automatic identification system because of its various advantages and applications. However, many people know that invasions of privacy in RFID system is still critical problem that makes it difficult to be used. Many works for solving this problem have focused on light-weight cryptographic functioning in the RFID tag. An agent scheme is another approach that an agent device controls communications between the tag and the reader for protecting privacy. Generally an agent device has strong security modules and enough capability to process high-level cryptographic protocols and can guarantees consumer privacy. In this paper, we present an enhanced mobile agent for RFID privacy protection. In enhanced MARP, we modified some phases of the original MARP to reduce the probability of successful eavesdropping and to reduce the number of tag's protocol participation. And back-end server can authenticate mobile agents more easily using public key cryptography in this scheme. It guarantees not only privacy protection but also preventing forgery.