Which cloud service model provides comprehensive access to infrastructure resources?

The Infrastructure as a Service (IaaS) model is distinguished by its provision of comprehensive access to infrastructure resources, which include servers, storage, and networking capabilities. Users of IaaS can provision and manage these resources according to their needs, allowing for significant flexibility and control over the computing environment. This model is particularly beneficial for businesses and developers who require customized setups for applications or workloads, enabling them to scale resources up or down based on demand without the need for physical hardware investment.

In contrast, Platform as a Service (PaaS) offers a platform allowing developers to build, deploy, and manage applications without worrying about the underlying infrastructure. While it provides essential resources, it does not grant the same level of infrastructure access as IaaS. Software as a Service (SaaS) delivers applications over the internet, managed by third-party providers; users interact with the software without any backend infrastructure management. The term "Community" typically refers to a cloud deployment model rather than a service model, indicating a shared infrastructure among several organizations with common concerns. Therefore, IaaS stands out as the model that grants comprehensive access to infrastructure resources necessary for greater customization and management.