The deployment model divides clouds into private, public (public) and hybrid.
Private clouds are internal cloud infrastructure and enterprise services. These clouds are within the corporate network. An organization can manage a private cloud itself or outsource the task.
The infrastructure can be hosted either at the customer’s premises or by an external operator, or partially at the customer’s premises and partially at the operator’s premises. An ideal private cloud is a cloud deployed on an organization’s premises, serviced and controlled by its employees.
Private clouds have the same advantages as public clouds, but with one important feature: the enterprise itself is engaged in installing and maintaining the cloud. The complexity and cost of building an internal cloud can be very high and the cost of running it can exceed the cost of using public clouds.
It should be noted that private clouds have advantages over public clouds: more detailed control over different cloud resources provides companies with any available configuration options. In addition, private clouds are ideal for performing work that cannot be trusted to the public cloud for security reasons.
Public clouds are cloud services provided by a provider. They are outside the corporate network. Users of these clouds do not have the ability to manage or maintain this cloud, the responsibility rests with the cloud owner. The cloud service provider assumes responsibility for installing, managing, providing and maintaining software, application infrastructure or physical infrastructure. Customers only pay for the resources they use.
At the same time, public cloud services are mainly provided as standard configurations, i.e. based on the conditions of the most common usage cases. This means that the user has fewer options for choosing a configuration compared to systems in which resources are managed by the user himself.
It should also be kept in mind that because consumers have little control over the infrastructure, processes that require strict security and compliance measures are not always suitable for implementation in a public cloud.
Hybrid clouds are a combination of public and private clouds. Typically, they are created by an enterprise and the responsibilities for managing them are shared between the enterprise and the public cloud provider. A hybrid cloud provides services, some of which are public clouds and some are private clouds. Typically, this type of cloud is used when an organization has seasonal periods of activity.
In other words, as soon as the internal IT infrastructure is not performing its current tasks, some capacity is transferred to a public cloud, as well as to provide users with access to enterprise resources (to a private cloud) through a public cloud. A well-designed hybrid cloud can serve both security critical processes, such as receiving payments from customers, and more marginal processes.
The main drawback of this type of cloud is the complexity of effectively creating and managing such solutions. You need to obtain services from different sources and organize them as if they were a single source. The interaction between private and public components can further complicate the solution.
As this is a relatively new architectural concept in the field of cloud computing, more and more practical recommendations and tools are emerging for this model, and its widespread adoption may take longer until it is better understood.
Five main points that help to get a more accurate idea of the private cloud device:
- Cloud is not necessarily a source of savings.
One of the main misconceptions is that the cloud will save money. Savings are possible, but not a mandatory attribute.
- A private cloud can more effectively redistribute resources to meet corporate requirements and can reduce capital expenditures on equipment.
But a private cloud requires investment in automation, and savings alone may not recoup the full cost. So, cost reduction is not the main advantage of this model. From this point of view, the main incentive to implement the cloud model should not be savings, but the speed of market entry, the ability to quickly adapt and dynamically scale in response to demand, which can increase the speed of implementation of new services.
- A private cloud is not always implemented at the customer’s premises.
A private cloud means privacy, not a specific location, resource ownership or self-management. Many vendors offer non-local private clouds, i.e. allocate resources to a single customer, excluding the sharing of a single pool by several customers. A cloud is private because of its privacy, not because of where it is deployed, who owns it and who is responsible for its management. Some may, for example, host their data centers or pool the resources of different customers, but isolate them from each other using and other similar technologies.
- A private cloud (like a public cloud) is not just infrastructure services.
Server virtualization is a major trend and therefore a powerful engine for private cloud computing. But a private cloud is not just about infrastructure as a service . For example, to develop and test new software, a high level platform as a service makes more sense than just providing virtual machines.
Today, the fastest growing segment of cloud computing is IaaS. It provides the lowest tier data center resources in an easy-to-use form, but does not fundamentally change the way it works. To create new applications that were originally designed for the cloud and provide completely new services that may be very different from what the previous applications gave, developers are better off using PaaS.
- A private cloud may no longer be private.
On the one hand, a private cloud provides the benefits of a cloud: it is fast to rebuild, scalable and efficient, eliminating some of the security threats, potential and real, that characterize public clouds. On the other hand, over time, the level of service, security and compliance in public cloud services will certainly improve.
It is therefore possible that some private clouds will become public clouds in their entirety. Most private cloud services, on the other hand, are likely to evolve into hybrid cloud services, expanding the available features through the use of public cloud services and other third-party resources.