The rapid evolution of smart grids requires effective communication protocols to transfer data reliably and securely. Controller Area Network (CAN) is one of the most recognized protocols that offer reliable data transmission in smart grids due to its robustness, real-time capabilities, and relatively low initial cost of its required hardware. However, as a smart city becomes more interconnected, it also becomes more vulnerable to cyber-attacks. As there are many mechanisms to secure the CAN nodes from attacks, most of those mechanisms have computational overhead, resulting in more delay in the network. We implemented a solution that requires almost no overhead to any CAN node connected to the network. It depends on a single node responsible for securing the CAN network. This approach seeks to augment network security while reducing security mechanisms overhead to all CAN network nodes. The methodology and comprehensive test results will be presented in detail during a subsequent discussion. The used software for development is Code Composer Studio, and the used microcontroller evaluation boards (EVB) are TM4C 1294.