A FUZZY DECISION MAKER FOR WIRELESS SENSOR NETWORK IN UBIQUITOUS NETWORK ENVIRONMENT

Abstract

Large range of tiny embedded sensor devices capable of sensing, communicating and routing data is available now days. Due to higher failure rate of sensor nodes or their mobility, the sink node might not exist in their transmission range. We propose an approach which uses fuzzy logic to deal with diverse QoS requirements of sensor applications. We have designed, an Intelligent Intermediate Robust Gateway (IIRG) module, which provides an efficient and consistent QoS based connectivity to sensor applications to outside world. This Gateway defines a decision structure needed by sensor network applications to switch over to any wireless network, in order to make communication with the remote sink fulfilling application QoS requirement. The result of our approach shows that it is capable of selecting appropriate network for range of sensor network applications. So far many different approaches have been adopted, for making these switching decisions and among all of these approaches, MADM (Multiple Attribute Decision Making) is considered as one of the approach for solving such types of vertical handover problems. The types of few MADM algorithms are AHP, TOPSIS, MEW and SAW. A comparison between these MADM algorithms has been done. Results of each algorithm and their response against the decision ranking have been analyzed. It is observed that TOPSIS is suffering from non stability in behavior; MEW shows penalizing behavior towards poor attributes, where as AHP and SAW shows less risk in decision ranking with minimum standard error mean and statistical variance.