• Journal of Communications and Networks
• /
• v.6 no.2
• /
• pp.156-162
• /
• 2004

In recent years, mobile ad-hoc networks have received a great deal of attention in both academia and industry to provide anytime-anywhere networking services. As wireless networks are rapidly deployed, the security of wireless environment will be mandatory. In this paper, we describe a group key management architecture and key agreement protocols for secure communication in mobile ad-hoc wireless networks (MANETs) overseen by unmanned aerial vehicles (UAVs). We use implicitly certified public keys method, which alleviates the certificate overhead and improves computational efficiency. The architecture uses a two-layered key management approach where the group of nodes is divided into: 1) Cell groups consisting of ground nodes and 2) control groups consisting of cell group managers. The chief benefit of this approach is that the effects of a membership change are restricted to the single cell group.

• The KIPS Transactions:PartC
• /
• v.10C no.6
• /
• pp.763-768
• /
• 2003

In this paper, we propose a S/KEY based authentication protocol using smart cards to address the vulnerebilities of both the S/KEY authentication protocol and the secure one-time password protpcol which YEH, SHEN and HWANG proposed [1]. Because out protpcel is based on public key, it can authenticate the server and distribute a session key without any pre-shared secret. Also, it can prevent off-line dictionary attacks by using the randomly generated user is stored in the users smart card. More importantly, it can truly achieve the strength of the S/KEY scheme that no secret information need be stored on the server.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.1
• /
• pp.31-40
• /
• 2014

In Korea, the Public Key Infrastructure (PKI) has been introduced. For secure information transmission and identification, the electronic signature authorization system of a certificate-based is built, and then the service provide.The certificate is stored in location what users can easily access and copy. Thus, there is a risk that can be stolen by malware or web account hacking. In addition, private key passwords can be exposed by the logging tool, after keyboard security features are disabled. Each of these security weaknesses is a potential conduit for identity theft, property/asset theft, and theft of the actual certificates. The present study proposes a method to prevent the private key file access illegally. When a certificate is stored, the private key is encrypted by the dependent element of the device, and it is stored securely. If private key leakage occurs, the retrieved key could not be used on other devices.

• Journal of the Korea Convergence Society
• /
• v.8 no.12
• /
• pp.9-14
• /
• 2017

Recently, the Internet of Things are developing in accordance with the technology of implementation in low-cost, small-size, low power consumption and smart sensor that can communicate using the internet. Especially, key management researches for secure information transmission based on the Internet of Things (IoT) are actively performing. But, Internet of Things(IoT) are uses sensor. Therefore low-power consumption and small-memory are restrictive condition. As a result, managing the key is difficult as a general security measure. However, The problem of secure key management is an essential challenge For the continuous development of the Internet of things. In this paper, we propose a key distribution and management technique in secure Internet of things. In the key generation and management stage, it satisfies the conditions and without physically constrained for IoT based communication.

• The KIPS Transactions:PartC
• /
• v.11C no.7 s.96
• /
• pp.971-980
• /
• 2004

This paper describes the design and implementation of the video conferencing system using public key infrastructure which is used for user authentication and encryption. Public key infrastructure reinforces the authentication process for conference participant, and the symmetric key system blocks malicious access to information and protect conference control information. This paper shows the implementation of the trans portation layer secure protocol in conformity with Korea public key authentication algorithm standard and symmetric encryption algorithm (DES, 3DES and AES) for media stream encryption. In this paper, we deal with two ways of protecting information : transportation layer secure protocol secures user authentication process and the conference control information; while public key-based authentication system protects personal information of users when they connect to the network. When distributing the session keys for encryption, Internet Key Exchange is used for P2P communication, and secure protocol is employed for 1 : N multi-user communication in the way of distributing the public key-based en-cryption key.

• Journal of KIISE:Information Networking
• /
• v.36 no.5
• /
• pp.437-455
• /
• 2009

In the near future, various multicast based services will be provided over clustered wireless networks. To provide multicast services in secure manner, multicast messages are encrypted by using group key which is shared by group members. Therefore, various group key management schemes have been introduced until now. Among them, tree based approach is one of the most representative paradigms in group key management. Traditional tree based approaches effectively reduce rekeying message transmissions of the key distribution center. However, they do not consider the network bandwidth used for transmitting the rekeying messages. In this paper, we firstly present formulas that describe bandwidth consumption of tree based group key management scheme. Based on our formulations, we propose a bandwidth efficient key tree management scheme for clustered wireless networks where membership changes occur frequently. Simulation results show that our scheme effectively reduces the bandwidth consumption used for rekeying compared to existing key tree schemes.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.14 no.6
• /
• pp.69-78
• /
• 2004

During the last decade, security models have been defined for two- and three-parity key exchange protocols. Currently there is a growing research interest in security models for group key management schemes. While various security models and provably secure protocols have been proposed for distributed group key exchange schemes, no results are hewn for centralized group key distribution schemes in spite of their theoretical and practical importance. We describe security requirements and a formal security model for centralized group key distribution scheme: we define the model on the channel controlled by adversaries with the ability of strong user corruption. In the security model, we propose a conversion module which can transform centralized tree-based group key distribution schemes in the literature to provably secure centralized tree-based group key distribution schemes.

• Journal of Advanced Navigation Technology
• /
• v.16 no.4
• /
• pp.679-686
• /
• 2012

Many researches have proposed key management schemes for Smartgrid System. However, previous studies lack the proper considerations for availability and device security. In this paper, we build up cryptographic security improvement for robust Smartgrid Systems. In addition, we propose a public-key management and hash function architecture for robust Smartgrid Systems which supports reduces the number of key and Secure Device in AMI network environments.

• Journal of information and communication convergence engineering
• /
• v.7 no.2
• /
• pp.98-106
• /
• 2009

Process Control Systems (PCSs) or Supervisory Control and Data Acquisition (SCADA) systems have recently been added to the already wide collection of wireless sensor networks applications. The PCS/SCADA environment is somewhat more amenable to the use of heavy cryptographic mechanisms such as public key cryptography than other sensor application environments. The sensor nodes in the environment, however, are still open to devastating attacks such as node capture, which makes designing a secure key management challenging. In this paper, a key management scheme is proposed to defeat node capture attack by offering both forward and backward secrecies. Our scheme overcomes the pitfalls which Nilsson et al.'s scheme suffers from, and is not more expensive than their scheme.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
• /
• 2003.07a
• /
• pp.21-25
• /
• 2003

Key exposure is the most devastating attacks in any crytographic scheme. In this paper, we investigate key exposure problem in blind signature. We then present a variant of Okamoto-Guillou-Quisquater (OGQ for short) blind signature scheme guaranteeing forward secrecy. Namely, even if current secret key is revealed, forging any signature valid in the past is impossible. Our proposed scheme exhibits an efficient key updating protocol and introduces no significant communication overhead.