WSN:

• WSN stands for Wireless Sensor Network. A WSN system incorporates a gateway that provides wireless connectivity back to the wired world and distributed nodes.
• WSNs can be used to monitor and/or control physical environment in a space where it is difficult or impossible to do so manually. A WSN is generally composed of a centralized station (sink) and tens, hundreds, or thousands of tiny sensor nodes.
• With the integration of information sensing, computation and wireless communication, these devices can sense the physical phenomenon, pre-process the raw information, and share the processed information with their neighboring nodes.
• The sensor nodes can form a WSN either ad hoc or with, for example, a cluster-based architecture. The sink node can query information and sometimes control the behavior of the sensor nodes.
• The information is often unidirectional flow from the sensor nodes to the sink. Since a WSN has a centralized sink and unidirectional information flow, it acts as a centralized system.
• But the sensor nodes are distributed and behave collaboratively. At the same time, WSM is not only a database system but also a resource-constrained network with most networking functions, so they are often used to monitor events and collect data. Hence, the environment is event driven and data centric.
• Hence, WSNs are a special type of distributed network system that is similar to database, real-time and embedded systems.
• A wireless sensor network (WSN) has important applications such as remote environmental monitoring and target tracking.
• This has been enabled by the availability, particularly in recent years, of sensors that are smaller, cheaper, and intelligent. These sensors are equipped with wireless interfaces with which they can communicate with one another to form a network.
• The design of a WSN depends significantly on the application, and it must consider factors such as the environment, the application’s design objectives, cost, hardware, and system constraints.

Applications of WSN:

• Health care monitoring.
• Air pollution monitoring
• Forest fire detection
• Landslide detection
• Water quality monitoring
• Natural disaster prevention

Advantages:

• It can accommodate new devices at any time.
• Flexible to go through physical partitions.
• It can be accessed through a centralized monitor.

Disadvantages:

• Comparatively low speed of communication.
• Gets distracted by various elements.
• Costly at large.