Certificate of Cloud Security Knowledge (CCSK) Practice Test 2025 - Free CCSK Practice Questions and Study Guide

The primary responsibility for the underlying physical infrastructure in an Infrastructure as a Service (IaaS) model rests with the physical layer. This layer includes the tangible components such as the servers, storage devices, networking hardware, and the data center facilities that house all of these resources. In an IaaS environment, users can provision and manage virtualized computing resources that run on this physical infrastructure, enabling them to deploy and manage applications without needing to invest in or manage physical hardware directly.

In contrast, the other layers mentioned play different roles within the cloud computing stack. The application layer is concerned with the software applications providing end-user services. The platform layer deals with middleware and development environments that support application development. The hypervisor layer is responsible for creating and managing virtual machines but does not constitute the physical infrastructure itself; it operates on top of the physical layer to abstract and allocate physical resources to virtual machines.

Understanding the structure of IaaS highlights the importance of the physical layer, as it forms the foundation upon which cloud services and virtual infrastructure are built.