Distributed Methods for Multi-Sink Wireless Sensor Networks Formation

Introduction

A Wireless Sensor Network (WSN) is composed of a set of hundreds of devices deployed in a common area, which are connected among them. Each device has the same capabilities; it is able to collect information from the surrounding environment through one or more sensors, process this information in a local manner. Data collection is usually made by a sink node or base station. A WSN can be used to control multiple tasks in one environment; the sensors require of data sensed from multiple sources by delivering information to multiple sinks at the same time.

There are a wide variety of current research problems in this area, such as tracking, surveillance, military applications, building automation, disaster management, and agriculture, among others. The applications are designed to obtain precise information from the environment regardless of the human presence. Radio communication, processing, transmission/reception generally are the main cause of power consumption. A multi-sink approach is becoming an efficient scheme to reduce the energy consumption in the whole network, either in a centralized or distributed application. In this paper, distributed techniques are presented and analysed.

The analysis is focused on the used strategies in a multiple sink environment, whether the nodes are static or mobile and how applications can be improved by mixing more than one strategy; the objective of the application such as event detection, following a target, finding the best route, collecting and data aggregation, among others. The survey covers recent and traditional works and presents a discussion of their advantages and drawbacks. A simple and operational distributed algorithm that performs network formation and data collection using a multi-sink environment is presented.

This article is organized as follows: the next section presents the generalities and features of WSNs. The third section presents a classification of distributed approaches based on multi-sink environments; the fourth section describes the classification of the related works and discusses their proposals. The fifth section focuses on the simple and operational proposal of a distributed and multi-sink protocol for a WSN; finally, the last section presents the concluding remarks, which drive further research in the area.