Abstract:
Wireless sensor networks (WSNs) form an important part of industrial application.
There has been growing interest in the potential use of WSNs in applications such as environment
monitoring, disaster management, health care monitoring, intelligence surveillance and defence
reconnaissance. In these applications, the sensor nodes (SNs) are envisaged to be deployed in
sizeable numbers in an outlying area, and it is quite difficult to replace these SNs after complete
deployment in many scenarios. Therefore, as SNs are predominantly battery powered devices,
the energy consumption of the nodes must be properly managed in order to prolong the network
lifetime and functionality to a rational time. Different energy-efficient and energy-balanced routing
protocols have been proposed in literature over the years. The energy-efficient routing protocols
strive to increase the network lifetime by minimizing the energy consumption in each SN. On the
other hand, the energy-balanced routing protocols protract the network lifetime by uniformly
balancing the energy consumption among the nodes in the network. There have been various
survey papers put forward by researchers to review the performance and classify the different
energy-efficient routing protocols for WSNs. However, there seems to be no clear survey emphasizing
the importance, concepts, and principles of load-balanced energy routing protocols for WSNs. In this
paper, we provide a clear picture of both the energy-efficient and energy-balanced routing protocols
for WSNs. More importantly, this paper presents an extensive survey of the different state-of-the-art
energy-efficient and energy-balanced routing protocols. A taxonomy is introduced in this paper to
classify the surveyed energy-efficient and energy-balanced routing protocols based on their proposed
mode of communication towards the base station (BS). In addition, we classified these routing
protocols based on the solution types or algorithms, and the input decision variables defined in the
routing algorithm. The strengths and weaknesses of the choice of the decision variables used in the
design of these energy-efficient and energy-balanced routing protocols are emphasised. Finally, we suggest possible research directions in order to optimize the energy consumption in sensor networks.