If you need ISO 27017 for certification or compliance:

The document summarizes ISO/IEC 27017 cloud computing security standard requirements that apply to cloud service customers. Scribd

The primary contribution of ISO 27017 is its clarification of the relationship between Cloud Service Providers (CSPs) and Cloud Service Customers (CSCs). Traditional security models often struggle with the ambiguity of "who owns which risk." ISO 27017 addresses this by providing guidelines on: