The cloud infrastructure dedicated solely to a single organisation, hosted…

NIST SP 800-145 classifies cloud deployment models chiefly by who has exclusive or shared use of the infrastructure. A private cloud is provisioned exclusively for one organisation — it may be hosted on that organisation's own premises or run by a third party. A public cloud is offered to the general public over the internet by a third-party provider. A community cloud is shared by several organisations that have common concerns. A hybrid cloud composes two or more of these distinct infrastructures together.

The stem describes infrastructure that is (a) dedicated solely to one organisation and (b) hosted within that organisation's own premises — an on-premises deployment reserved for exclusive use by one organisation is exactly a private cloud, so matching this exclusive-use criterion against the taxonomy above identifies it as a private cloud.

• public cloud — open to any customer over the internet; not restricted to a single organisation.

• community cloud — shared by multiple organisations with common needs; still not single-tenant.

• hybrid cloud — a combination of at least two separate cloud infrastructures interoperating; not one wholly on-premises setup.

So the cloud infrastructure dedicated solely to a single organisation within its own premises is a private cloud.