Soon-seok Lee

An efficient anti-DDoS mechanism using flow-based forwarding technology

During the last “7.7 cyber attack”, a lot of web servers in Korea suffered from DDoS attacks even while most of the systems are believed to be guarded by various kinds of security systems. This is because it takes long to analyze and detect the attacks to filter out the traffic in most of the current anti-DDoS systems. In this paper, we propose an anti-DDoS mechanism using flow-based network forwarding technology which filters out DDoS attack traffic effectively before the other professional anti-DDoS systems can finish analysis of the attacks and react against them.

Cooperative Scenario based Centralized Defense Mechanisms for Low-Rate TCP Attacks

The low-rate TCP attack has been reported recently. That is essentially a periodic short burst which exploits the homogeneity of the minimum retransmission timeout (RTO) of TCP flows. It is difficult to identify this sort of attack in BcN (broadband convergence network) due to no cooperative defense mechanisms among different networks. In this paper, NCP (network control platform) based centralized defense mechanisms are proposed. Firstly, low-rate TCP attack and the previous defense mechanisms are reviewed. It helps us to find and select reasonable features of them for supporting the proposed mechanism. Secondly, we propose a cooperative defending scenario between NCP as centralized controller and MDRs (monitoring and defending routers). Without adopting defense mechanism to all routers in network, it is possible to effectively protect network resource from low-rate TCP. That is because the attack flows can be filtered at both victim-side and attack side MDRs with cooperative scenario. The performance id evaluated by using ns-2 simulator