WIRELESS SENSOR NETWORKS: INTRODUCTION

Before, I actually begin; I wish to recall the movie “Twister”. Hopefully, many of you would have watched this movie. If not, no worries. In this movie, a particular group of scientists fight their way into the mouth of a tornado to release sensors to gather data about the interior of a tornado. At that instant, I realized that they were actually releasing were Wireless sensor networks capable of collecting data about the tornado.

Observation is crucial for scientific progress because it forms the basis of any study. Advances in semi-conductor technology have spurred the growth of devices with large computing power and lost cost. Every year, the size and the cost of these devices are decreasing exponentially. Researchers are using this technology to gather data more efficiently and thereby creating a new dimension of computing in science.

With better fabrication techniques, it is now possible to integrate sensor, computing device and a networking device in a single system. These systems are highly proficient in interacting with the environment and collect more information which effectively increases the quality of any study.

Systems are built with miniature radios and exceptionally small mechanical devices which sense the quality of physical world. Such systems are inexpensive and are densely deployed capable of coordinating with each other. Combining such systems with system software technology has made instrumentation of the world possible with high fidelity.

To realize this venture demands more challenges. The individual systems in the Wireless Sensor Network (WSN) are inherently resource constrained:

• The computing devices operate on low memory, limited processing speed and low communication bandwidth
• The desire of WSN to be autonomous places a severe energy constraint. 

So, the design for such systems has to be in a way that these systems process information and give maximum output on an aggregate, not individually.

In most WSN settings, in order to minimize energy consumption, most of the device’s components, likely the radio are turned off. Also, the individual nodes are subjected to harsh environmental conditions. Furthermore, since the nodes are densely deployed, there will be a high degree of interaction between them and there is a greater need for developing architecture and protocols which allows their efficient operation.

Despite these challenges, the nodes must remain inexpensive and must organize themselves to program and manage the network as a whole.