Denial of Service (DoS) attack is a threat in today's network because DoS attacks are easy to launch, while defending a network resource against them is very difficult. DoS attack is an attempt to make a machine or network resource unavailable to its legitimate users. It has put tremendous pressure over security experts in bringing out effective defense solutions. These attacks could be implemented with variety of tools and codes. Large number of countermeasure techniques tries to detect the attack and filter it out. In this paper a study is made on recent techniques on Denial of Service protection. Our discussion aims to identify the current methods in detection and mitigation of DoS attacks in the network.

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Traffic Feature Conditional Entropy (tfce) Genetic Algorithm (ga) Cumulative Sum (cusum).