This document discusses securing the smart grid, particularly at the edge where many small and resource-constrained devices are located. It notes that hackers have previously infiltrated nuclear power plant systems through external networks. While more complex smart devices have sufficient processing power and encryption for security, simple devices require solutions that use little code space and power. The document proposes a solution using a lightweight cipher and authentication protocol to securely transmit smart meter data along the power supply network. Key challenges in implementing security include managing a large number of keys and providing privacy and authentication without excessive processing demands. Event management and responding to situations in real time is also an issue requiring mature infrastructure.