I. Introduction
The Advanced Metering Infrastructure (AMI) is one of the prominent applications in Smart Grid (SG) [1]. The AMI assists in upgrading the current power system using bidirectional communication between smart meter devices at homes and servers. A widely applied routing protocol in AMI is Routing Protocol for Low-Power and Lossy Networks (RPL) [2]. The next-generation electricity grid, AMI, needs a reliable two-way communication protocol. However, RPL nodes select sub-optimal or insecure routing paths with low-quality links, and they suffer from severe unreliability problems. Moreover, the design of a reliable RPL protocol for AMI systems is a critical challenge due to the adversarial activities and constrained resources of the smart meter nodes [3]. Recently, AMI networks allow huge and various numbers of smart meters. With the expansion of network size and new services in AMI, the packet sending frequency between smart meters and gateway systems grows drastically. It tends to be many issues in the provision of security protection. For example, the attacker can compromise the smart devices in the system to carry out several routing attacks, such as a Rank attack, Hello Flood attack, DoS attack, and Version Number Attack. Therefore, in the AMI with resource-restricted smart meters, how to carry out a reliable and secure routing is particularly important [4].