Multitenancy is the aspect of cloud computing that involves having multiple customers and applications running within the same system and sharing the same resources. Although considerable mechanisms are in place to ensure isolation and separation, the data and applications are ultimately using shared resources. Broad network access refers to the ability to access cloud services from any location or client.
Portability refers to the ability to easily move cloud services between different cloud providers, whereas elasticity refers to the capabilities of a cloud environment to add or remove services, as needed, to meet current demand.

When leasing space in a data center, an organization can avoid the enormous startup and building costs associated with a data center, and can instead leverage economies of scale by grouping with other organizations and sharing costs.

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Regardless of the particular cloud service used, physical security of hardware and facilities is always the sole responsibility of the cloud provider. The cloud provider may release information about their physical security policies and procedures to ensure any particular requirements of potential customers will meet their regulatory obligations. Personal security of developers and regulatory compliance are always the responsibility of the cloud customer. Responsibility for operating systems, and the auditing of them, will differ based on the cloud service category used.