No abstract

Wireless sensor network (WSN) is becoming famous because of its use in various applications of different areas such as environment, defense, medical, house, media and education. WSN is a structure free network where requirement of application decides the network structure, topology and routing protocols. Data transmission in sensor network is possible with the help of routing protocols. There are multiple routing protocols in WSN which provide efficient data delivery but reliability is still a major constraint of WSN. When data is transmitted from source node to the sink or Base Station (BS), some data packets may lost due to some reason such as failure of node, dead node. Sometimes node is not interested in forwarding data and drops the data packet. The problem of lost data affects the reliability of the network. Various energy efficient protocols have been proposed but they do not ensure reliability. This paper studies the reliability issue. Also highlights some of the proposed techniques to make network more reliable.