In cloud security architecture, security elements are added to cloud architecture. Cloud security always involves a shared responsibility between the cloud provider and the cloud consumer. The division of responsibility depends on the type of cloud structure you are using: IaaS, PaaS, or SaaS. There is a division of responsibility imagined by the International Organization for Standardization (ISO), NIST, and even the Cloud Security Alliance (CSA). In the end, however, it will be determined by the cloud provider and customer and written into the contract.
As a cloud customer, it is important to do a risk assessment to ensure you understand the consequences of using any form of cloud. If you’re not building your own cloud in your own data center, the contract should state who is responsible for what, or at a minimum, what you can rely on the cloud provider to do.