Author(s): Rupinder Singh1, Dr. Jatinder Singh2, Dr. Ravinder Singh2

Wireless sensor network (WSN) is a collection of dispersed and dedicated sensors nodes for monitoring, recording the physical conditions of the environment, and organizing the collected data at a central location. WSN are playing a great role in the controlling and managing environments in different situations and has become important part of research area. WSN research is usually classified into three categories i.e. hardware & software of the sensors nodes, application area and communication & security. Due to limited resources of computation power, battery, communication range, WSN are vulnerable to different types of attacks and hello flood attack is one of them. This attack is performed by malicious node by flooding the hello request to the legitimate node continuously in order to break the security. In this paper we first describe the working of hello flood attack and then we discuss various countermeasures proposed in the literature for tackling with hello flood attack. A detailed study of these countermeasures with their limitations is the need of the time so that new and improved one can be proposed in the future for more robust security against hello flood attack