Abstract: “Internet users have been attacked by widespread email viruses earlier, but now scenario has been changed. Now attackers are no more interested to just attract media attention by infecting a large number of computers on the network; in fact, their interest has been shifted to compromising and controlling the infected computers for their personal profits. This new attack trend brings the concept of botnets over the global network of computers. With the high reported infection rates, the vast range of illegal activities and powerful comebacks, botnets are one of the main threats against the cyber security. This paper provides the readers with a background on botnet life-cycle, architecture and malicious activities. It also classifies botnet detection techniques, reviews the recent research works on botnet traffic detection and finally indicates some challenges posed to future work on botnet detection.”

Keywords: Cyber security, malware, botnet, C&C server, intrusion detection system.