A wireless sensor network (WSN) is one form of system or setup in which multiple sensor nodes are interconnected with each other through a wireless communication medium.
Each sensor node is a tiny energy-bounded, multifunctional device that collects data from its nearby environment then performs some sort of computation on collected data.
Then send all this gathered data towards the main base station or sink.
Category 1 WSNs (C1WSNs)
These are invariably mesh-based systems with multihop radio connectivity among or between WSNs.
It utilizes dynamic routing in both the wireless and wireline portions of the network.
C1WSNs are networks in which end devices like sensors are permitted to be more than one radio hop away from a routing or forwarding node.
The forwarding node is a wireless router that supports dynamic routing.
Wireless routers are often connected over wireless links.
Features of C1WSNs:
Sensor nodes can support communications on behalf of other sensor nodes by acting as repeaters.
The forwarding node supports dynamic routing and more than one physical link to the rest of the network is
physically and logically present.
The radio links are measured in thousands of meters.
The forwarding node can support data processing or reduction on behalf of the sensor nodes.
These all features made it a relatively Complex and meshy wireless system.
An example of this type of network is Military theater systems.
Category 2 WSNs (C2WSNs)
These are point-to-point or multipoint-to-point star-based systems generally with single-hop radio connectivity to WSNs.
It utilizes static routing over the wireless sensor network.
Typically, there will be only one route from the WSNs to the companion terrestrial/wireline forwarding node.
C2WSNs are networks in which end devices like sensors are one radio hop away from a terrestrially homed forwarding node.
The forwarding node calls it a wireless router that is connected to the terrestrial network via either a landline or a point-to-point wireless link.
Features of C2WSNs:
Sensor nodes do not support communications on behalf of any other sensor nodes.
The forwarding node supports only static routing to the terrestrial network, and only one physical link to the terrestrial network is present.
The radio link is measured in hundreds of meters.
The forwarding node does not support data processing or reduction on behalf of the sensor nodes.
These all features made it a relatively simple wireless system.
An example of this type of network is Residential control systems.