• Proceedings of the Korean Information Science Society Conference
• /
• 2012.06d
• /
• pp.366-368
• /
• 2012

Network Coding approach to IP tracback was proposed by Sattari et al. [5] in order to reduce number of packets required to trace the source of a single attack scenario. In this paper, we analysis and point out limitations and problems of their proof for benefit of network coding to IP traceback.

• Proceedings of the IEEK Conference
• /
• 1999.11a
• /
• pp.89-92
• /
• 1999

This paper describes on the threats such as IP spoofing, denial of service, and ILMI based attack etc. for IP over ATM network. Especially we discuss on the threats due to ATM characteristics that are VC stealing, multiparty and multi-connection call. Also we investigate on the threats of ATM based MPLS network. Finally we discuss and suggest the various solutions of ATM security.

• Proceedings of the IEEK Conference
• /
• 2000.07b
• /
• pp.743-746
• /
• 2000

In this paper we propose a new network called Dynamic network for symmetric block ciphers. Dynamic cipher has the property that the key-size, the number of round, and the plaintext-size are scalable simultaneously We present the method for designing secure Dynamic cipher against meet-in-the-middle attack and linear cryptanalysis. Also, we show that the differential cryptanalysis to Dynamic cipher is hard.

• International Journal of Computer Science & Network Security
• /
• v.22 no.7
• /
• pp.157-164
• /
• 2022

The proposed privacy preserving scheme has identified the drawbacks of existing schemes in Vehicular Networks. This prototype enhances the number of nodes by decreasing the cluster size. This algorithm is integrated with the whale optimization algorithm and Block Chain Technology. A set of results are done through the NS-2 simulator in the direction to check the effectiveness of proposed algorithm. The proposed method shows better results than with the existing techniques in terms of Delay, Drop, Delivery ratio, Overhead, throughout under the denial of attack.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.2
• /
• pp.173-181
• /
• 2011

User authentication and key exchange protocols are the most important cryptographic applications. For user authentication, most protocols are based on the users' secret passwords. However, protocols based on the users' secret passwords are vulnerable to the password guessing attack. In 1992, Bellovin and Merritt proposed an EKE(Encrypted Key Exchange) protocol for user authentication and key exchage that is secure against password guessing attack. After that, many enhanced and secure EKE protocols are proposed so far. In 2006, Lo pointed out that Yeh et al.'s password-based authenticated key exchange protocol has a security weakness and proposed an improved protocol. However, Cao and Lin showed that his protocol is also vulnerable to off-line password guessing attack. In this paper, we show his protocol is vulnerable to on-line password guessing attack using new attack method, and propose an improvement of password authenticated key exchange protocol for imbalanced wireless networks secure against password guessing attack.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.8
• /
• pp.95-104
• /
• 2013

DDoS attacks have became as a social threat since 2009 7.7 DDoS turmoil. Even though defence techniques have been developing to provide against those threats, they become much more sophisticate. In recent years, the attack form of DDoS is changing from high amount of traffic attack of network layers to highly sophisticate small amount of application layers. To make matters worse, attack agent for the attack has became very intelligent so that it is difficult to be blocked since it can't be distinguished from normal PCs. In the user authentication system(such as CAPTCHA) User intervention is required to distinguish normal PCs and intelligent attack agents and in particular, in a NAT environment, IP-based blocking method can be cut off the normal users traffic at the same time. This research examined defense techniques which are able to distinguish between agent and normal PC and effectively block ways the HTTP DDoS offense applying one-time session key based authentication method using Cookie which is used in HTTP protocol to protect web sever from sophisticate application layer of DDoS.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.4
• /
• pp.809-817
• /
• 2012

One of the OSI 7 Layer DDoS Attack, HTTP POST DDoS can deny legitimate service by web server resource depletion. This Attack can be executed with less network traffic and legitimate TCP connections. Therefore, It is difficult to distinguish DDoS traffic from legitimate users. In this paper, I propose an anomaly HTTP POST traffic detection algorithm and http each page Content-Length field size limit with defense method for HTTP POST DDoS attack. Proposed method showed the result of detection and countermeasure without false negative and positive to use the r-u-dead-yet of HTTP POST DDoS attack tool and the self-developed attack tool.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.5
• /
• pp.1041-1051
• /
• 2012

Attack on Cloud Computing, an intensive service solution using network infrastructure recently released, generates service breakdown or intrusive incidents incapacitating developmental platforms, web-based software, or resource services. Therefore, it is needed to conduct research on security for the operational information of three kinds of services (3S': laaS, PaaS, SaaS) supported by the Cloud Computing system and also generated data from the illegal attack on service blocking. This paper aims to build a system providing optimal services as a 4-stage defensive method through the test on the attack and defense of Cloud Computing services. It is a defense policy that conducts 4-stage, orderly and phased access control as follows: controlling the initial access to the network, controlling virtualization services, classifying services for support, and selecting multiple routes. By dispersing the attacks and also monitoring and analyzing to control the access by stage, this study performs defense policy realization and analysis and tests defenses by the types of attack. The research findings will be provided as practical foundational data to realize Cloud Computing service-based defense policy.

• The KIPS Transactions:PartC
• /
• v.11C no.6 s.95
• /
• pp.711-718
• /
• 2004

Packet sampling is the techniques to collect a part of the packets through network and analyze the characteristicsof the traffic for managing the network and keeping security. This paper presents a study on the sampling techniques applied to DDoS traffic and on the characteristics of the sampled traffic to detect DDoS attack efficiently and improve traffic analysis capacity. Three famous sampling techniques are evaluated with different sampling rates on various DDoS traffics. To analyze traffic characteristics, one of the DDoS attack detection method. Traffic Rate Analysis (TRA) is used. Simulation results verify that using sampling techniques preserve the traffic characteristics of DDoS and do not significantly reduce the detection accuracy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.05a
• /
• pp.650-652
• /
• 2013

As VANET(Vehicular Ad-hoc NETwork) improves road safety, efficiency, and comfort, and provides a value-added service such as commerce information or internet access. it is the most important technology in ITS(Intelligent Transportation System). But, In VANETs, better communication efficiency can be achieved by sacrificing security and vice versa. VANETs cannot get started without either of them. Therefore, to solve these problems simultaneously, this paper proposes MAC(Message Authentication Code) based SDAP(Secure Data Aggregation Protocol) which removes redundant data or abnormal data between vehicles and verifies the integrity of message. The MAC based SDAP not only improves the efficiency of data delivery but also enhances the security by detecting malicious attacks such as propagation jamming attack, forgery attack, and disguised attack.