Important changes in electricity consumption model require a communication network within the electrical grid, which is called the Advanced Metering Infrastructure (AMI) that can handle the increase of multiple and fluctuating production sites. Recently, we witness the convergence of this communication network and the electricity network into what is now called Smart Grid. This communication network will serve the purpose of automatic meter reading, but new usages and services could be developed on top of this network. The massive integration of renewable energy sources will shift the production level close to the consumption sites. Therefore, new communication models are required to control the energy consumption depending on the production capabilities. In this Chapter, we explain why a two-way communication network is necessary for future Smart Grid. Furthermore, we present the required network characteristics, and we particularly describe what are the current protocols selected to achieve these goals.