As opposed to the conventional DoS attacks, Low rate DOS Attacker injects a short burst of traffic periodically to fill up the bottleneck buffers right before the expiration of the sender’s RTO. This forces the sender’s TCP connections to timeout with very low throughput. These attacks are hard to detect and prevent, as most of the DoS attack detection systems are triggered by high-rate traffic. This paper presents the survey of techniques available for detecting Low rate Do’S attacks and compares them using various parameters.