A public cloud is one based on the standard cloud computing model, in which a service provider makes resources, such as applications and storage, available to the general public over the Internet. Public cloud services may be free or offered on a pay-per-usage model.
In public clouds the resources are shared between multiple clients and all the services are controlled by services provider.
Public clouds rely on a third-party cloud service provider for services such as servers, data storage and applications, which are delivered to the company through the Internet. A public cloud can free companies from the potentially expensive costs of having to purchase, manage and maintain on-premises hardware and software infrastructure.
Public clouds can also typically be deployed much faster and with more scalability and accessibility than on-premises infrastructure as a result of the public cloud provider’s expertise and existing infrastructure. Public cloud subscribers may pay pay-as-you-go fees or fixed monthly fees for the public cloud services they utilize
The main benefits of using a public cloud service are:
- Easy and inexpensive set-up because hardware, application and bandwidth costs are covered by the provider.
- Scalability to meet needs.
- No wasted resources because you pay for what you use.
The term "public cloud" arose to differentiate between the standard model and the private cloud
, which is a proprietary network or data center that uses cloud computing technologies, such as virtualization. A private cloud is managed by the organization it serves. A third model, the hybrid cloud
, is maintained by both internal and external providers.
PUBLIC CLOUD ADVANTAGES
Simple and easy: Public clouds are available as a service in the internet, they are easy to deploy.
Cost: Initial investment is very low or nil.
Less time: The IT resources and services are available immediately saving time for the company.
No maintenance: The hardware and networks are maintained by the cloud services provider. Internal IT staffs have no responsibility in maintaining the infrastructure.
No contracts: No long term commitment with service provider because public clouds are usually pay-as-you-go models.
PUBLIC CLOUD DISADVANTAGES
Lacks proper controls: The client has no control of data or infrastructure. There are issues of data privacy and integrity. The service level policies and compliances are completely enforced by the service provider.
Performance: The performance of the network depends on the speed of the internet connectivity.
Weak on Security: Since the hardware resource is shared between multiple users, IT security issues are more profound and data is vulnerable to thefts.
Customization: Customization of resources or services is not possible.