Decoupling data dissemination from the mobile sink's trajectory in wireless sensor networks: Current Research and Open Issues

The aim of Wireless Sensor Networks (WSNS) is to accumulate data and in this perspective, firstly the need of distributed data management emerges and gain vital importance. Secondly data dissemination of this accumulated data has its own importance. Now distributed data management and data dissemination is an essential paradigm in wireless sensor networks resulting in minimizing the number of transmissions, eliminating the redundant data, conserve the energy, and thus resulting in the overall increase in the lifetime of the network. Traditionally data dissemination has been done by utilizing static sinks. These static sinks were not only prone to hotspots problem but also decrease throughput, increase the number of transmitted packets, less energy conservation of sensor nodes, and above all decrease the overall network lifetime. To deal with these aforementioned problems the need of incorporating mobile sink arises. Now the paradigm of distributed data management and data dissemination is shifting from static sink to mobile sink and now more and more research work has been done in the domain of mobile sink wireless sensor networks. In this report, firstly, we presents state of the art survey on Data Management and Data Dissemination techniques with Mobile Sink. Moreover we classify these techniques into two ample sub-categories. Under this classification, we identify, review, compare, and highlight these techniques and their pros and cons. We do a SWOT (Strength, Weaknesses, Opportunities, Threats) analysis of each scheme. We also discuss where each scheme is appropriate. Secondly, we presents a new distributed data management scheme which is based upon Random Walk Based Membership Service to facilitate Data Dissemination in Mobile Sink based Wireless Sensor Networks. Our proposed scheme efficiently deals with the aforementioned problems and we also compare the characteristics of our proposed scheme with the state-of-the-art data-dissemination schemes. We propose using Random Walks (RWs) with uniformly distributed views to disseminate data through the WSN with a controlled overhead. This is performed by the use of a Random Walk Based Membership Service the RaWMS. Our proposal solves then the problems generated when (a) all nodes are storage motes, being no aggregation performed (b) one center node plays the role of storage mote and aggregates data from all the other nodes (c) replication is performed on all nodes in the network. To the best of our knowledge, we are the first to propose an efficient data dissemination approach (in terms of overhead, adaptiveness and representativeness) to allow a mobile sink to gather a representative view of the monitored region covered by n sensor nodes by only visiting any m nodes, where hopefully m << n.