A Survey of Fault Tolerance Methods in Wireless Sensor Networks

---------------------------------------------------------------------***--------------------------------------------------------------------Abstract In Wireless Sensor Networks (WSN’s) fault tolerance is one of the most important critical issues. The difficulty of missing communication link, Node and data are ineluctably foreordained in WSN’s and due to assorted factors such as power drain, environmental crash, radio interference, asymmetric communication links, dislocation of sensor node and collision, network experience failure quandaries. Many that are able To attain higher data reliability, precision, energy preserving, network lifetime enhancement and minimize failure of components researchers have proposed various fault tolerant mechanisms in WSN’s . This paper state a significant analysis of fault tolerance mechanisms in wireless sensor networks such as Mobile Agent(MA) mechanisms, relay node mechanisms and Hand Over mechanisms to identify the strengths and importance of each one of these mechanisms. Collectively, this paper suggests some of future research directions that will be contributory for researchers who are working in Wireless sensor field.