Contrail project (Collaborative project): Open Computing Inftrastructures for Elastic Services (2010-2013). Seventh Research Framework Programme (FP7). Contract No 257438. The goal of the Contrail project is to design, implement, evaluate and promote an open source system in which resources that belong to different operators are integrated into a single homogeneous Federated Cloud that users can access seamlessly. Contrail will vertically integrate an open-source distributed operating system for autonomous resource management in Infrastructure-as-a-Service environments, and high level services and runtime environments as foundations for Platform-as-a-Service.