A systematic review on heterogeneous routing protocols for wireless sensor network

• A complete taxonomy for heterogeneous WSNs is provided so that users can select one of the categories based upon its merits over the others.
• A detailed analysis of protocols in different categories with respect to various performance evaluation parameters has been presented in the paper.
• A detailed comparison of various protocols with respect to different metrics with advantages/disadvantages is performed.

The latest developments in wireless communication are more focused on delivering sensitive information to its final destination under several constraints such as energy, latency, reliability, stability, and security. Through the latest developments in digital technology, wireless transceiver, and Micro-Electro-Mechanical Systems (MEMS), it is possible to integrate sensing and computing units along with transceiver and power supply to a single unit called as Sensor Node (SN). The collection of SNs built a specialized type of network called as Wireless Sensor Networks (WSNs). Many pre-existing research proposals on WSNs have focused mainly on minimization of energy consumption during the process of sensing, computation, and transferring data to the Base Station (BS) using gateways. Although clustering is the most prominent technique for the enhancement of network lifetime by efficient energy utilization of SN, but node heterogeneity is another interesting aspect which can be used to save the energy consumption of SNs in the network field. Keeping in view of all these issues, in this paper, we have categorized various heterogeneous routing protocols for WSNs based upon various predefined parameters. Relative comparison of various protocols with other existing state-of-the-art protocols is provided with respect to various performance evaluation parameters such as- CH Selection, Energy Efficiency, Security, and Application Specific. The broad categorization gives insights to various users to select one of the protocols from different categories based upon its merits over the others.