Public Cloud vs Private Cloud: What’s The Difference? | Telehouse
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Public and Private Cloud: The Difference

As their data requirements and costs continue to increase, more and more businesses are considering cloud-based solutions. Perhaps the most attractive benefit is the strong cost-efficiency that outsourcing business data operations to the cloud can provide. This is thanks in part to economies of scale, particularly in the domains of energy and operating costs. 
However, while most cloud service providers offer excellent frameworks for cutting down on the operational costs of traditional hosting, the decision to make first is whether to opt for Public cloud or Private cloud services.
Below we present a comparative overview to help you to make the right decision when moving to the cloud.

What is public cloud?

A cloud service which is made available to the general public, often on a pay-as-you-go basis, is customarily referred to as a Public Cloud. Since its services can be utilised by the customers on-demand, without an agreement on a fixed rate, it is a textbook example of utility computing. In essence, users only pay by the hour for the resources they have used. Additionally, some public cloud services are free of charge.
Public Clouds are also known as multi-tenant environments. They’re often thought of as being effective solutions to the common problem of network or hardware bottlenecking. It wouldn’t be an exaggeration to say that Public Cloud Computing was conceived primarily to provide increased computing performance, while at the same time lowering business costs and the need to plan resource usage ahead of time.
Consequently, with a public cloud setup, all the responsibilities associated with maintaining infrastructure and service stability such as backups, disaster recovery or updates are transferred to service providers. However, it is also worth noting that some of the cloud vendors on the market will expect their users to be responsible for their application level security. A user and an operator could, therefore, share the responsibility for the security of the intermediate layers of the software stack, while public cloud providers remain accountable for physical security and enforcing external firewall policies.

What is private cloud?

A private cloud is also known as a single tenant environment, in which computing resources are rented by a single client or company. The definitive element of a private cloud is that it is dedicated to serving the needs of an individual enterprise, with virtual private clouds being the only exception to this rule.
Traditional Private Cloud hosting is a proprietary, customised infrastructure that, if not outsourced to a data centre, is otherwise built on the premises of a company, and linked to its own private network.
Private hosting is not considered to be utility computing since it can’t be purchased in the pay-as-you-go manner and has a flat rate attached to it instead.  Most often, the beneficiaries of such models prove to be large enterprises with a strong usability plan which help them to avoid over-provisioning or under-provisioning.
Virtual Private Clouds, unlike their costly Private Cloud Computing counterparts, can be created within a multi-tenant public cloud environment shared by various users. The desired isolation here is achieved not by physical separation of hardware, but by a network-based separation granted with private subnets.
The importance of implementing virtualisation into digital systems is something which is stressed by Cloud providers, who advertise it as an inexpensive tool for theft and DDoS attack protection and distributed denial - of – service (DDoS) attacks. In essence, a healthy, bug- free virtualisation software will make it impossible, either for a user to attempt an attack on another user’s infrastructure or the sensitive portions of the provider’s cloud infrastructure.

Should you choose public or private cloud?

A common difference between public and some types of private cloud is that customers outsourcing their data function to a public cloud cease to be responsible for its management or maintenance and for the underlying complexity in general. This isn’t the case with some types of private cloud.
Therefore, proprietary architecture and as a result private cloud for all IT resources is often recommended for mid to large size enterprises. Especially for those organisations in which data security and compliance with data protection legislation are crucial. By having direct control of their data handling infrastructure, organisations can be made better prepared for avoiding and handling possible cyber-attacks.
Advocates for Private Cloud Computing also argue that it gives enterprises full control to allocate their resources, administer their network, and of course more freedom when it comes to choosing software solutions. Private Clouds are often quite easily scalable, as the vendors providing them are expected to provide new resources, whenever their clients find it necessary.
However, despite the range of advantages of single-tenant environments, these are not suitable in all cases and the choice between public cloud and private cloud is often not clear-cut. Although the single-tenant environment is often praised for being good value for money, financing a proprietary private cloud computing infrastructure is rarely described with the same enthusiasm. The initial investment in hardware alone can be quite substantial creating a barrier to entry, thus public cloud deployments are generally favoured by small and mid-size companies.
When choosing between a public cloud or private cloud solution for their computing requirements, companies need to have their business and security objectives in mind. Anyone who is concerned about complying with data protection regulations or directives should consider Private Cloud deployment as their model for virtualised resources. Equally, those who are just at the beginning of their entrepreneurial journey and don’t have more than broad predictions about the scalability of their offering would probably be better served with public cloud services.