The quality of service is the main feature of Internet services. To fault these services of the web server or a website, the attacker uses a Denial of Service (DoS) attack and these DoS attacks now-a-days can be easily detected using many attack detection tools. The Low-Rate Denial of Service (LRDoS) attacks are a new type of DoS attacks that sends high intensity requests in an ON/OFF pattern to degrade victim’s performance and evade the detection designed for traditional DoS attacks. It is more difficult for traditional DoS attack detection method to detect LRDoS attack.