You can read first part of the tutorial here
Based on the target users of a cloud services, physical placement and management of cloud infrastructure, NIST has defined four cloud deployment services namely public cloud, private cloud, hybrid cloud and community cloud, the major being the first three.
The cloud infrastructure is for the sole use of a single entity. This could be an organization or an administration. Here the services are provisioned, managed, and operated by the organization or a third party with whom the organization has signed a contract or some combination of them.
Characteristics of Private Cloud
- The private cloud could be hosted inside office premises or outside.
- Private Cloud is fully dedicated for an entity. Private Cloud could be managed by the entity which owns it or by a vendor by contractual agreement with an entity.
- Private Cloud usually requires high investment compared to other cloud deployment models
When to go for Private Cloud?
- When the information stored in the cloud is sensitive and it requires high control and security.
- When performance of service is critical for the organization
The public cloud is available to all. It may be owned, managed, and operated by a cloud service provider and the user can avail the service for pay per use cost.
Characteristics of Public Cloud
- Public Cloud don't require initial upfront investment. Users pay for usage.
- It lives on the premises of the cloud provider. It’s always off-site for cloud users
When to go for public cloud?
- When the focus is on reducing capital expenses.
- When the data is not really critical
- When the processing requires high scalability and flexibility in terms of computing power
Hybrid cloud is a composition of two or more distinct cloud infrastructures (private, community, or public) that remain unique entities, but are bound together by standardized or proprietary technology that enables data and application portability