Comprehensive and Detailed Explanation From Exact Extract:

In a colocation data center model, the facility (building, power, cooling, physical security, and connectivity) is owned and managed by a third-party provider, while the enterprise typically installs and manages its own servers and network equipment inside that facility. The key difference from an on-premises data center is who is responsible for operating and managing the physical environment.

An on-premises data center is located at and operated by the enterprise itself, which means the organization directly manages the building infrastructure, power, cooling, physical access, and related facilities.

Option A is incorrect because using dedicated hardware provided by the enterprise can occur in both on-premises and colocation models. It does not clearly distinguish colocation from on-premises.

Option B is incorrect because being located within the enterprise's premises describes an on-premises data center, not a colocation center.

Option C is incorrect because ownership and operation by the enterprise also corresponds to an on-premises model.

Option D is correct because a colocation data center is managed by a third-party provider, who is responsible for the physical site and its supporting infrastructure while the enterprise uses that space to host its equipment.

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