• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2019.05a
• /
• pp.288-289
• /
• 2019

This paper studies the secrecy capacity for a wireless cooperative network with perfect channel state information at the relays, and receiver. A similar assumption is also made for the instance where there exist a direct link between the transmitter and receiver. Physical Layer security techniques are employed in wireless networks to mitigate against the activity of eavesdroppers. It offers a viable alternative to computationally intensive encryption. In this paper the design of a protocol utilizing jamming (via jamming nodes) for better security and relaying (via relay nodes) for the amplify-and-forward (AF) operation, is investigated. A a signal-to-noise variant of secrecy known as secrecy gap is explored because of its use of lesser computational power - preferable for practical systems. Thus we maximize this signal-to-noise approach instead of the conventional secrecy capacity maximization method. With this, an iterative algorithm using geometric programming (GP) and semi-definite programming (SDP) is presented with appreciable benefits. The results show here highlight the benefits of using fractional components of the powers of the relays to offer better secrecy capacity.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.14 no.1
• /
• pp.59-69
• /
• 2004

Password-based authenticated group key exchange protocols provide a group of user, communicating over a public(insecure) channel and holding a common human-memorable password, with a session key to be used to construct secure multicast sessions for data integrity and confidentiality. In this paper, we present a password-based authenticated group key exchange protocol and prove the security in the random oracle model and the ideal cipher model under the intractability of the decisional Diffie-Hellman(DH) problem and computational DH problem. The protocol is scalable, i.e. constant round and with O(1) exponentiations per user, and provides forward secrecy.

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

• Convergence Security Journal
• /
• v.23 no.4
• /
• pp.43-52
• /
• 2023

Many businesses and organizations use smartcard-based user authentication for remote access. In the meantime, through various studies, dynamic ID-based remote user authentication protocols for distributed multi-server environments have been proposed to protect the connection between users and servers. Among them, Qiu et al. proposed an efficient smart card-based remote user authentication system that provides mutual authentication and key agreement, user anonymity, and resistance to various types of attacks. Later, Andola et al. found various vulnerabilities in the authentication scheme proposed by Qiu et al., and overcame the flaws in their authentication scheme, and whenever the user wants to log in to the server, the user ID is dynamically changed before logging in. An improved authentication protocol is proposed. In this paper, by analyzing the operation process and vulnerabilities of the protocol proposed by Andola et al., it was revealed that the protocol proposed by Andola et al. was vulnerable to offline smart card attack, dos attack, lack of perfect forward secrecy, and session key attack.

• Journal of KIISE:Information Networking
• /
• v.32 no.6
• /
• pp.659-667
• /
• 2005

A Mobile Ad Hoc Network(MANET) is a multi hop wireless network with no prepared base stations or centralized administrations, where flocks of peer systems gather and compose a network. Each node operates as a normal end system in public networks. In addition to it, a MANET node is required to work as a router to forward traffic from a source or intermediate node to others. Each node operates as a normal end system in public networks, and further a MANET node work as a router to forward traffic from a source or intermediate node to the next node via routing path. Applications of MANET are extensively wide, such as battle field or any unwired place; however, these are exposed to critical problems related to network management, node's capability, and security because of frequent and dynamic changes in network topology, absence of centralized controls, restricted usage on network resources, and vulnerability oi mobile nodes which results from the special MANET's character, shared wireless media. These problems induce MANET to be weak from security attacks from eavesdropping to DoS. To guarantee secure authentication is the main part of security service In MANET because networks without secure authentication are exposed to exterior attacks. In this paper, a multistage authentication strategy based on CGSR is proposed to guarantee that only genuine and veritable nodes participate in communications. The proposed authentication model is composed of key manager, cluster head and common nodes. The cluster head is elected from secure nodes, and key manager is elected from cluster heads. The cluster head will verify other common nodes within its cluster range in MANET. Especially, ID of each node is used on communication, which allows digital signature and blocks non repudiation. For performance evaluation, attacks against node authentication are analyzed. Based on security parameters, strategies to resolve these attacks are drawn up.

• Convergence Security Journal
• /
• v.12 no.6
• /
• pp.11-17
• /
• 2012

Network security performance evaluation is a complex and diverse system environments, a single, specific performance measurements alone performance evaluation measure itself and the meaning of the reliability of the evaluation results do not limit the number of days only. In this paper, we propose a method to measure the security features of security, QoS measurement techniques using MOS satisfaction. MOS(Mean Opinion Score) Rating specifications for network security, QoS satisfaction and how to operate the development and operational model for future customer's satisfaction for information systems that can be used to evaluate the QoS measurement/analysis be utilized in the field. Objectified in the form of standards and performance measurement system provider (supplier development) and consumers(users) all the results available so that how to develop a system. Development is the development of information security features, the performance of these two features networking capabilities and a comprehensive evaluation of a three-gaeyoungyeok Correlating performance measurement methodology. Systematic measurement environment designed using the proposed methodology of this study, when the operating system is on the satisfaction of the security, QoS can be calculated. Forward In addition, a variety of performance metrics and performance measurement methods by extending the network security system satisfaction rating upgrade by the way will be.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.6
• /
• pp.1077-1082
• /
• 2019

The development of computing technology and networking has developed into a fundamental technology of the Fourth Industrial Revolution, which provides a ubiquitous environment. In the ubiquitous environment, the IoT environment has become an issue so that various devices and the things can be actively accessed and connected. Also, the RFID system using the wireless identification code attaches an RFID tag to the object, such as the production and distribution of products. It is applied to the management very efficiently. EPCglobal is conducting a research on RFID system standardization and various security studies. Since RFID systems use wireless environment technology, there are more security threats than wire problems. In particular, failure to provide confidentiality, indistinguishability, and forward safety could expose them to various threats in the Fourth Industrial Revolution. Therefore, this study analyzes the standard method of EPCgolbal and proposes RFID security method using hash code that can consider the amount of computation.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.1B
• /
• pp.1-10
• /
• 2003

An EPON which is going on standardization in IEEE 802.3ah, is tree topology consists of a OLT and multiple ONU using passive optical components, so this network is susceptible to variable security threats - eavesdropping, masquerading, denial of service and so on. In this paper, we design a security protocol supporting authentication and confidentiality services in MAC layer in order to prevent these security threats and to guarantee secure data exchange The designed security protocol introduce public-key based authentication and key management protocols for efficient key management, and choose Rijndael algorithm, which is recent standard of AES, to provide the confidentiality of EPON Proposed authentication and key management protocols perform authentication and public-key exchange at a time, and are secure protocols using derived common cipher key by exchanging public random number To implement the designed security protocol, we propose the procedures of authentication and public-key exchange, session key update, key recovery. This proposed protocol is verified using unknown session key, forward secrecy, unknown key-share, key-compromise impersonation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.2 no.6
• /
• pp.312-332
• /
• 2008

Password-based authentication key exchange (PAKE) protocols in the literature typically assume a password that is shared between a client and a server. PAKE has been applied in various environments, especially in the “client-server” applications of remotely accessed systems, such as e-banking. With the rapid developments in modern communication environments, such as ad-hoc networks and ubiquitous computing, it is customary to construct a secure peer-to-peer channel, which is quite a different paradigm from existing paradigms. In such a peer-to-peer channel, it would be much more common for users to not share a password with others. In this paper, we consider password-based authentication key exchange in the three-party setting, where two users do not share a password between themselves but only with one server. The users make a session-key by using their different passwords with the help of the server. We propose an efficient password-based authentication key exchange protocol with different passwords that achieves forward secrecy in the standard model. The protocol requires parties to only memorize human-memorable passwords; all other information that is necessary to run the protocol is made public. The protocol is also light-weighted, i.e., it requires only three rounds and four modular exponentiations per user. In fact, this amount of computation and the number of rounds are comparable to the most efficient password-based authentication key exchange protocol in the random-oracle model. The dispensation of random oracles in the protocol does not require the security of any expensive signature schemes or zero-knowlegde proofs.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.18 no.5
• /
• pp.49-57
• /
• 2008

User authentication and key agreement are very important components to provide secure home network service. Although the TTA adopted the EEAP-PW protocol as a user authentication and key transmission standard, it has some problems including not to provide forward secrecy. This paper first provides an analysis of the problems in EEAP-PW and then proposes a new attribute-based authenticated key agreement protocol, denoted by EEAP-AK. to solve the problems. The proposed protocol supports the different level of security by diversifying network accessibility for the user attribute after the user attribute-based authentication and key agreement protocol steps. It efficiently solves the security problems in the EEAP-PW and we could support more secure home network service than the EEAP-AK.