Routing protocols in wireless sensor networks

Presently quite a lot of WSN protocols are available using different techniques
to ensure proper routing of authentic data; each protocol has its own advantages
and disadvantages in design.
The figure below shows the different network architectures and routing
techniques used by the protocols to work.
Fig 1.4a: Routing protocols in WSNs.
The figure shows three different network structures:
Flat routing:
Each sensor nodes behaves the same way and co-operates with other nodes to
perform the sensing task. The network contains a large number of such nodes
and a Base Station (BS) sends queries to certain regions and waits for data from
the sensors located in the selected regions. Data-centric routing is used where
there is no global identifier for nodes; instead data is identified using attribute
based naming.
Hierarchical Routing:
This routing method have special advantages related to scalability and efficient
communication, they also provide energy-efficient routing in WSNs.
Location-Based Routing:
Sensor nodes are addressed depending on their locations. Relative coordinates
of neighboring nodes is obtained either by exchanging information between
neighbor nodes or by directly communicating with a Global Positioning System
(GPS). [8]
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