This Recommendation provides the functional framework for resource scheduling among multiple cloud service providers (CSPs) and its functional requirements based on multiple CSPs’ interconnection relationship (multi-CSP IR) modelling and Infrastructure as Code (IaC). It describes typical use cases and derives the corresponding functional requirements on several aspects, including model lifecycle management, model selection and instantiation, model repository management, model resolution, IaC environment establishment, and lifecycle management for heterogeneous resource deployment.