Internet of Things and Data Analytics Handbook

12WIRELESS SENSOR NETWORKS

DAVID Y. FONG

CITS Group, San Jose, CA, USA

12.1 INTRODUCTION

Wireless Sensor Networks (WSN) play a critical role in Internet of Things (IoT). They are the interface of the IoT system to the physical world, collecting information from the terminals and sending it back to the system. Each node of the network is responsible for sensing and collecting certain physical properties, sending and receiving information to and from other nodes in the network, and aggregating the information. The information collected is sent to a gateway and fed into the Internet.

In the past decade, the cost of sensors, actuators, microprocessors, and network infrastructures has come down rapidly, making the WSN a practical reality. Many applications that were too expensive to operate are now within reach with reasonable cost.

In many cases, the sensor nodes are deployed in remote areas or difficult‐to‐access locations, drawing operating power from a battery, and communicate wirelessly. Due to this nature, the sensor nodes need to consume very little power and be able to self‐organize in the context of network configuration in case of individual node failure.

However, even in cases where sensors are sufficiently small, smart, and inexpensive, challenges remain. In addition to power consumption, they include data security and interoperability.

In this chapter, we describe the characteristics of the WSN and analyze the power constraints, the network operation, the operating ...