Advanced Metering Infrastructure (AMI), seen as foundation for overall grid modernization, is an integration of many technologies providing an intelligent connection between consumers and system operators. One of the biggest challenges that AMI faces is to gather and process huge amounts of metering data. This requires a scalable communication architecture which provides adequate aggregation bandwidth while allowing to efficiently process metering data. In this paper, we introduce a novel communication architecture for AMI in which metering data is aggregated and processed in a tree-like topology. Through analysis we show that the architecture is scalable and resilient in presence of failure and partly self-organization. The experiments performed in large scale French Grid5000 platform also show the efficiency of communication of the proposed architecture.