What key characteristic defines cloud computing services?

Cloud computing services are primarily characterized by on-demand network access to a shared pool of configurable computing resources. This essential feature allows users to easily provision and release resources as needed, often through a self-service portal. The “on-demand” aspect highlights that users can obtain resources instantly without requiring human interaction with service providers, which increases efficiency and flexibility in how organizations manage their IT resources.

The shared resources mention implies that the infrastructure is typically multi-tenant, allowing multiple customers to use a single pool of resources while maintaining data isolation and security, which is a fundamental characteristic of cloud architecture. This model also contributes to cost-effectiveness, as resources can be allocated dynamically based on demand.

In contrast, the other options present characteristics that are not defining aspects of cloud computing. High maintenance requirements suggest a need for significant ongoing management, which is contrary to the cloud model that promotes ease of use and lower maintenance. Exclusive access implies a restriction that doesn’t align with the collaborative and flexible nature of cloud services, as they are designed for broad accessibility. A heavy reliance on physical infrastructure goes against the cloud principle of abstraction and virtualization, where users interact with resources independent of the underlying hardware.