Analysis of Countermeasures for DDoS Attacks and Evaluation of Entropy based Detection Mechanism using NS2

An attack which deprives legitimate users of the services rendered by a server is termed as a DDoS Attack. Since, attacks like these have already proved to be detrimental for the standard functionalities of the World Wide Web so there crops up an exigency for making our systems proactively smart and cautious in order to counteract such situations. In the view of the past records of the DDoS attacks, sincere researches have been made in this area and several new techniques and methods have been devised as well. However, this does not deter attackers from taking a step back; they are also equally earnest in finding new ways of attacking to outsmart these countermeasures. The paper covers the architecture of Botnet for the basic understanding of DDoS attacks and the need to combat the same. Along with botnet taxonomy, it discusses the methodologies that have been developed and implemented so far. It also talks about the upcoming techniques like Entropy based detection mechanism that are on the radar of development and testing to counterattack the ever growing new nefarious designs of the attackers.