A Fuzzy logic based objective function to improve reliability of RPL routing protocol in LLNs

In wireless networks, a routing protocol is considered critical for the efficient transmission of packets along with MAC protocol. RPL protocol is introduced as a routing protocol for LLNs. RPL protocol is designed to offer the best path for data packet transmission in the specific resource constraint environment, such as the limitation of battery power, processing, and storage. It uses an objective function to choose the best routing paths for data packet transmission in the wireless network. However, the key limitation of these objective functions is that they use a single routing metric namely, Expected Transmission Count (ETX) or Hop Count. The use of single routing metric results in the degradation of the overall performance of the RPL protocol in the LLNs. In order to address this issue, various schemes are proposed by different researchers. This paper provides a thorough analysis of the composite routing metric whose objective is to mitigate the limitation of a single routing metric. A fuzzy logic-based scheme framework is also proposed in this paper to resolve this single routing metric limitation.