This document discusses the methodology for designing IOT platforms. It includes specifications for purpose and requirements, processes, domains, information, services, and functional and operational views. It also provides examples of applying this methodology to design an IOT-based weather monitoring system. The system uses sensors to collect environmental data like temperature, pressure and humidity from multiple nodes. The nodes send the data to the cloud for aggregation, analysis and storage in a database. Diagrams show the system's domain model, controller service, deployment design and mapping of functional groups to operational specifications.