Energy efficient distributed flooding time synchronization Protocol for Heterogeneous WSN's

摘要

Wireless sensor networks had attracted interest of researchers in the decade due to number of challenges and applications. It is a type of ad hoc network that consist of hundred of nodes and can be deployed and work without human intervention. These nodes are micro sensors which are less in their price and therefore have different constraints. Nodes work together using wireless networking in different areas such as accurately monitoring the environmental conditions and then aggregate the data to form useful information. There are number of other applications of Wireless sensor networks. The nodes require working together for distributed tasks and accurate, reliable time is one of the needs for some of its applications. The protocols used for the clock synchronization for wired network are not suitable for wireless sensor networks due to severe energy constraints. The protocols in wired network need to send messages to server again and again to get synchronized, which is not possible in Wireless sensor networks. The reliable and energy efficient clock synchronization have different challenges, which are intensively working out by the researchers in this field. In this paper work, we propose that clock synchronization provide overhead and these overheads can be eliminated up to some extent. Physical clock synchronization is not possible and we advocate the concept of virtual clocks, which are used for the purpose of synchronization. The wireless sensor networks are single hop and multi hop in nature. We use a method "Waiting Flood" which is a hybrid protocol.