• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.442-444
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• 2004

서비스 거부 공격은 그 피해의 규모에 비해 방어하기가 무척 어려우며 충분히 대비를 한다 해도 알려지지 않은 새로운 서비스 거부 공격 기법에 피해를 입을 위험성이 항상 존재한다. 또한 최근 나타나고 있는 서비스 거부 공격 기법은 시스템 자원을 고갈시키는 분산 서비스 거부 공격(DDoS)에서 네트워크의 대역폭을 고갈시킴으로서 주요 네트워크 장비를 다운시키는 분산 반사 서비스 거부 공격(DRDoS)으로 진화하고 있다 이러한 공격 기법은 네트워크 트래픽의 이상 징후로서만 탐지될 뿐 개별 패킷으로는 탐지가 불가능하여 공격 징후는 알 수 있으되 자동화된 대응이 어려운 특징이 있다. 본 논문에서는 이미 알려진 공격뿐 아니라 새로운 서비스 거부 공격 패킷을 탐지하기 위하여, 패턴 분류 문제에 있어서 우수한 성능을 보이는 것으로 알려져 있는 Support Vector Machine(SVM)을 사용한 실험을 진행하였다. 테스트 결과. 학습된 공격 패킷에 대해서는 정확한 구분이 가능했으며 학습되지 않은 새로운 공격에 대해서도 탐지가 가능함을 보여주었다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.7 s.349
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• pp.72-83
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• 2006

It is not a practical solution that the DDoS attacks or worm propagations are protected and responded within a domain itself because it clogs access of legitimate users to share communication lines beyond the boundary a domain. Especially, the DDoS attacks with spoofed source address or with bogus packets that the destination addresses are changed randomly but has the valid source address does not allow us to identify access of legitimate users. We propose a scheme of distributed network security management to protect access of legitimate users from the DDoS attacks exploiting randomly spoofed source IP addresses and sending the bogus packets. We assume that Internet is divided into multiple domains and there exists one or more domain security manager in each domain, which is responsible for identifying hosts within the domain. The domain security manager forwards information regarding identified suspicious attack flows to neighboring managers and then verifies the attack upon receiving return messages from the neighboring managers. Through the experiment on a test-bed, the proposed scheme was verified to be able to maintain high detection accuracy and to enhance the. normal packet survival rate.

• Journal of Convergence for Information Technology
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• v.7 no.2
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• pp.1-9
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• 2017

Recently, the DDoS attack using the amplifier method makes it difficult to distinguish the normal traffic from the normal server and it is difficult to detect even the attack detection. Since the SSDP protocol is a common protocol widely used in IoT devices, it is used as a DDoS amplification attack. In this paper, we analyze the reflector attack of SSDP which is one of the DDoS and suggest a technical proposal to detect and defend against the attack by managing the Mac address of each device. Also, we propose a control structure to protect the reflection attack of SSDP in Home IoT. The efficiency of the proposed system has been verified by performing an experimental attack on the virtual environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.3
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• pp.449-455
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• 2021

This paper proposes an encryption web transaction attack detection system based on the existing web application monitoring system. Although there was difficulty in detecting attacks on the encrypted web traffic because the existing web traffic security systems detect and defend attacks based on encrypted packets in the network area of the encryption section between the client and server, by utilizing the technology of the web application monitoring system, it is possible to detect various intelligent cyber-attacks based on information that is already decrypted in the memory of the web application server. In addition, since user identification is possible through the application session ID, statistical detection of attacks such as IP tampering attacks, mass web transaction call users, and DDoS attacks are also possible. Thus, it can be considered that it is possible to respond to various intelligent cyber attacks hidden in the encrypted traffic by collecting and detecting information in the non-encrypted section of the encrypted web traffic.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.8 no.5
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• pp.429-437
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• 2015

DDoS attacks have been used for paralyzing popular Internet services. Especially, amplification attacks have grown dramatically in recent years. Defending against amplification attacks is challenging since the attacks usually generate extremely hugh amount of traffic and attack traffic is coming from legitimate servers, which is hard to differentiate from normal traffic. Moreover, some of protocols used by amplification attacks are widely adopted in IoT devices so that the number of servers susceptible to amplification attacks will continue to increase. This paper studies on the analysis of amplification attack mechanisms in detail and proposes defense methodologies for scenarios where attackers, abused servers or victims are in a monitoring network.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.5
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• pp.127-134
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• 2014

In DRDoS(Distributed Reflective Denial of Service) attacks, the victim is bombarded by packets from legitimate reflector unlike DDoS(Distributed Denial of Service) attacks through zombie, which is more dangerous than DDoS attack because it is in stronger disguise. Therefore, the method of filtering packet method on router are useless. Moreover SCTP(Stream Control Transmission Protocol) multi-homing feature, such as with an improved transmission protocol allows detecting attacks is more difficult and the effect of the attack can be maximized. In this paper we propose a DRDoS detection mechanism based on DRDoS utilizing attention to the characteristics of stateful protocols. The proposed scheme is backed by stateful firewall, and detect DRDoS attacks through a rules table and perform a defense treatment against DRDoS attack. Rules table with a simple structure is possible to easily adapt for any kind of stateful protocol can used by DRDoS attack. The experimental result confirm that our proposed scheme well detect DRDoS attacks using SCTP, the next-generation transmission protocol which not known by victim, and reduce the attacking packets rapidly.

• Proceedings of the Korea Contents Association Conference
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• 2004.05a
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• pp.278-282
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• 2004

Recently traffic flooding attack has happened faster and faster owing to expansion of the worm attack and development of the method of traffic flooding attack. The method in the past time is problematic in detecting the recent traffic flooding attacks, which are running quickly. Therefore, this paper aims to establish the algorithm which reduces the time of detection to traffic flooding attack in collecting and analyzing traffics.

• Journal of the Korea Society for Simulation
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• v.21 no.3
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• pp.17-24
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• 2012

This paper suggests Effectiveness Evaluation Methods of DDoS attacks countermeasures model by simulation. According to the security objectives that are suggested by NIST(National Institute of Standards and Technology), It represents a hierarchical Effectiveness Evaluation Model. we calculated the weights of factors that security objectives, security controls, performance indicator through AHP(Analytic Hierarchy Process) analysis. Subsequently, we implemented Arena Simulation Model for the calculation of function points at the performance indicator. The detection and protection algorithm involve methods of critical-level setting, signature and anomaly(statistic) based detection techniques for Network Layer 4, 7 attacks. Proposed Effectiveness Evaluation Model can be diversely used to evaluate effectiveness of countermeasures and techniques for new security threats each organization.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.16 no.1
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• pp.71-77
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• 2006

Several network attacks, such as distributed denial of service (DDoS) attack, present a very serious threat to the stability of the internet. The threat posed by network attacks on large networks, such as the internet, demands effective detection method. Therefore, a simple intrusion detection system on large-scale backbone network is needed for the sake of real-time detection, preemption and detection efficiency. In this paper, in order to discriminate attack traffic from legitimate traffic on backbone links, we suggest a relatively simple statistical measure, entropy, which can track value frequency. Den is conspicuous distinction of entropy values between attack traffic and legitimate traffic. Therefore, we can identify what kind of attack it is as well as detecting the attack traffic using entropy value.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.814-816
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• 2003

분산 서비스 거부 공격 기법이 점점 더 향상되어감에 따라 이에 대한 대응 기법 또한 여러가지가 제안되고 있다. 기존의 탐지에 기반을 둔 기법들은 공격을 탐지하기 위한 Rule이 미리 준비되어야 한다는 점에서 실제 트래픽과 구별이 어려운 DDoS 공격의 경우 효율적인 대응이 될 수 없다. 이를 극복하기 위해서 트래픽 감지와 QoS 기법에 기반을 둔 대응 방안이 활발히 연구 중에 있다. 본 논문에서는 현재까지 나와 있는 트래픽 감지 기반의 대응 기법 연구들을 정리하고 라우터 기반의 보안기능 개발 연구에서 트래픽 감지 기반의 대응 방안 적용 과정을 소개한다.