• Journal of Korea Multimedia Society
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• v.16 no.6
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• pp.678-688
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• 2013

Different Different from a single attack, in DDoS Attacks, the botnets that are distributed on network initiate attacks against the target server simultaneously. In such cases, it is difficult to take an action while denying the access of packets that are regarded as DDoS since normal user's convenience should also be considered at the target server. Taking these considerations into account, the DDoS botnet detection system that can reduce the strain on the target server by detecting DDoS attacks on each user network basis, and then lets the network administrator to take actions that reduce overall scale of botnets, has been implemented in this study. The DDoS botnet detection system proposed by this study implemented the program which detects attacks based on the database composed of faults and abnormalities collected through analyzation of hourly attack traffics. The presence of attack was then determined using the threshold of current traffic calculated with the standard deviation and the mean number of packets. By converting botnet-based detection method centering around the servers that become the targets of attacks to the network based detection, it was possible to contemplate aggressive defense concept against DDoS attacks. With such measure, the network administrator can cut large scale traffics of which could be referred as the differences between DDoS and DoS attacks, in advance mitigating the scale of botnets. Furthermore, we expect to have an effect that can considerably reduce the strain imposed on the target servers and the network loads of routers in WAN communications if the traffic attacks can be blocked beforehand in the network communications under the router equipment level.

• Journal of Convergence Society for SMB
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• v.5 no.1
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• pp.19-23
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• 2015

Distributed Denial of Service attack is a form of denial of service attacks, the attacker to attack a place in a number of points of attack by a wide variety of forms over the network to perform a service on a point attack . Do not use a specific server or client attempts to make a connection to many services available that prevents this attack and so normally used . Corresponding methods of DDoS attacks has a corresponding managerial aspects and technical aspects of the proposed two.

• The Journal of Korean Association of Computer Education
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• v.8 no.1
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• pp.65-72
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• 2005

In this study, we suggest a new mechanism on the design and implementation of IP Traceback system against DDos/DRDoS by Zombie and Reflector attack based on spoofed IP packets. After analysis and comparing on the state-of-arts of several IP traceback mechanisms, we can find their own pros and cons primitives. And then we performed simulations on reflector based DRDoS network packets. In first, we suggest a NS-2 based IP traceback module and implement it for finding its real DRDoS attacker. As a results, we can find advanced new IP traceback scheme for providing enhanced proactive functionality against DRDoS attack.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.729-732
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• 2010

통신망의 발달로 다양한 인터넷 기반 기술들이 등장함에 따라 현재는 데이터뿐만 아닌 음성에 대한 부분도 IP 네트워크를 통해 전송하려는 움직임이 발판이 되어 VoIP(Voice Over Internet Protocol)라는 기술이 등장하였다. SIP(Session Initiation Protocol) 프로토콜 기반 VoIP 서비스는 통신 절감 효과가 큰 장점과 동시에 다양한 부가서비스를 제공하여 사용자 수가 급증하고 있다. VoIP 서비스는 호(Call)를 제어하기 위해 SIP 기반으로 구성이 되며, SIP 프로토콜은 IP 망을 이용하여 다양한 음성과 멀티미디어 서비스를 제공하게 되는데 IP 프로토콜에서 발생하는 인터넷 보안 취약점을 그대로 동반하기 때문에 DoS(Denial of Service) 및 DDoS(Distribute Denial of Service)에 취약한 성향을 가지고 있다. DDoS 공격은 단시간 내에 대량의 패킷을 타깃 호스트 또는 네트워크에 전송하여 네트워크 접속 및 서비스 기능을 정상적으로 작동하지 못하게 하거나 시스템의 고장을 유도하게 된다. 인터넷 기반 생활이 일상화 되어 있는 현 시점에서 안전한 네트워크 환경을 만들기 위해 DDoS 공격에 대한 대응 방안이 시급한 시점이다. DDoS 공격에 대한 탐지는 매우 어렵기 때문에 근본적인 대책 마련에 대한 연구가 필요하며, 정상적인 트래픽 및 악의적인 트래픽에 대한 탐지 시스템 개발이 절실히 요구되는 사항이다. 본 논문에서는 SIP 프로토콜 및 공격기법에 대해 조사하고, DoS와 DDoS 공격에 대한 특성 및 종류에 대해 조사하였으며, SIP를 이용한 VoIP 서비스에서 IP 분류와 메시지 중복 검열을 통한 DDoS 공격 탐지기법을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7B
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• pp.489-498
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• 2005

A Denial of Sewice (DoS) attack attempts to prevent legitimate users of a sewice from being adequately served by monopolizing networks resources and, eventually, resulting in network or system congestion. This paper proposes a Minority First (MF) gateway, which is capable of guaranteeing the Quality of Service (QoS) of legitimate service traffic under DoS situations. A MF gateway can rapidly determine whether an aggregated flow is a congestion-inducer and can protect the QoS of legitimate traffic by providing high priority service to the legitimate as aggregate flows, and localize network congestion only upon attack traffic by providing low priority to aggregate flows regarded as congestion-inducer. We verify through simulation that the suggested mechanism possesses excellence in that it guarantees the QoS of legitimate traffic not only under a regular DoS occurrence, but also under a Distributed DoS (DDoS) attack which brings about multiple concurrent occurrences of network congestion.

• The Journal of the Korea Contents Association
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• v.7 no.1
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• pp.103-115
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• 2007

The vulnerability issue on IEEE 802.1x wireless LAN has been permits the malicious attack such as Auth/Deauth flooding more serious rather than we expected. Attacker can generate huge volume of malicious traffic as the same methods on existing wired network. The objective of wireless IP Traceback is to determine the real attack sources, as well as the full path taken by the wireless attack packets. Existing IP Traceback methods can be categorized as proactive or reactive tracing. But, these existing schemes did not provide enhanced performance against DoS attack on wireless traffic. In this paper, we propose a 'TTL based advanced Packet Marking' mechanism for wireless IP Packet Traceback with wireless Classification function. Proposed mechanism can detect and control DoS traffic on AP and can generate marked packet for reconstructing on the real path from the non-spoofed wireless attack source, by which we can construct secure wireless network based on AP with enhance traceback performance.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.05a
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• pp.252-255
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• 2002

As more critical services are provided in the internet, the risk to these services from malicious users increases. Several networks have experienced problems like Denial of Service(DoS) attacks recently. We analyse a network-based denial of service attack, which is called SYM flooding, to TCP-based networks. It occurs by an attacker who sends TCP connection requests with spoofed source address to a target system. Each request causes the targeted system to send instantly data packets out of a limited pool of resources. Then the target system's resources are exhausted and incoming TCP port connections can not be established. The paper is concerned with a detailed analysis of TCP SYN flooding denial of service attack. In this paper, we propose a Real Time Scan Detector(RTSD) mechanism and evaluate it\`s Performance.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.41-48
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• 2019

In 2018, Cui et al proposed a three-factor remote user authentication scheme using biometrics. Cui et al claimed that their authentication scheme is vulnerable to eavesdropping attack, stolen smart card attack, and especially Dos(denial-of-service) attack. Also they claimed that it is safe to password guessing attack, impersonation attack, and anonymity attack. In this paper, however, we analyze Cui et al's authentication scheme and show that it is vulnerable to replay attack, insider attack, stolen smart card attack, and user impersonation attack, etc. In addition, we present the design flaws in Cui et al's authentication scheme as well.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.447-452
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• 2013

Berkley Media Access Control (B-MAC) protocol is one of the well-known MAC protocols, which uses adaptive preamble sampling scheme and is designed for wireless sensor networks (WSN). In this paper, we are reviewed about security vulnerability in B-MAC, and analyzed the power which is consumed at each stage of B-MAC protocol according to vulnerability of denial of sleep(DoS) and replay problem. From our analytical results, it can be considered the need of power efficient authentication scheme which provides the reliability, efficiency, and security for a general B-MAC communication. This is the case study of possible DoS vulnerability and its power consumption in B-MAC.

• Journal of Korea Multimedia Society
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• v.12 no.9
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• pp.1323-1332
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• 2009

In this paper, we analyze security weakness of 4-Way Handshake in IEEE 802.11i and propose fast and secure 2-Way Handshake mechanism. Compute PTK(Pairwise Transient Key) using sequence number instead of random numbers in order to protect Replay attack and DoS attack. Also, proposed 2-Way Handshake mechanism can mutual authenticate between mobile station and access point and derive PTK using modified Re-association Request and Re-association Response frames. And, compare with others which are fast and secure Handoff mechanisms.