Energy consumption in wireless sensor networks 

In general wireless sensor networks operated with the help of battery power and the life of these batteries are fixed to certain limits and after some time the life can be expired. Optimizing the energy consumption is always required across the wireless sensor networks to save the battery power. There are different scenarios where the energy is consumed across the wireless sensor networks and all these scenarios should be considered to optimize the energy consumption across the wireless sensor networks. In general the sensors operated under the battery power and these sensors consume some energy at the communication level itself to route the packets and also maintain the routing tables.

Frequent updates to the routing tables involves lot of computation across the sink node of the wireless sensor networks and these computation consumes some energy with respect to the overall energy consumption across the wireless sensor networks.  In general the sensor nodes across the wireless sensor networks have some database capabilities and they process the query requests from the neighboring sensor nodes and pass little information across the network and even this process consumes ample energy across the wireless sensor networks.

The type of routing chosen across the wireless sensor networks also plays a vital role in deciding the energy consumption and the routing protocol plays an important role in the energy consumption process. In general there are three different types of routing protocols across the wireless sensor networks like proactive routing protocol, reactive routing protocols and hybrid routing protocols. Proactive routing protocols are table driven routing protocols and they operated under the guidance of the routing table information and the overall energy consumption across these routing protocols is very less as the routing is static in nature and there are no dynamic updates to the routing tables and the routing process is not affected to the dynamic changes in the topology of the wireless sensor networks.

Reactive routing protocols are dynamic in nature and on demand routing protocols. They are dynamic in nature and can change the routing decisions as per the changes in the topology and thus the energy consumption is more across the reactive routing protocols when compared to the proactive routing protocols. Hybrid routing protocols operates under the combined principles of the proactive and reactive routing protocols and thus the energy consumption is less when compared to proactive or reactive routing protocols as they routing decisions are changes as per the current networking conditions. The level of energy consumption also depends on type of routing followed like single path and multipath routing. In general single path routing consumes more energy when compared to the multipath routing.