Types of cloud computing are —
(i) Public Clouds –
The public cloud environment is that type of Cloud computing environments that are open for public use or that are open for all type of public and alternatively for a large industry group. Some public clouds are Google, Amazon, IBM offerings and many others that are available for the public for their commercial use.
(ii) Private Clouds –
Private Cloud is a cloud which is own by a particular organization for their private use of cloud computing. The cloud is implemented within the private premises of organizations or institution and uses it to provide services to the users of the institution of them. Therefore it is known as a private cloud.
(iii) Hybrid (Heterogeneous) Clouds –
Hybrid or Heterogeneous Clouds provide that type of cloud computing environment which combines two or more type of clouds where those clouds keep their unique identities within it but are combine or bound together as a single unit service.
It identifies as a private cloud that has been augmented with different resources or services hosted in public cloud. Because of these properties, it is known as Hybrid or Heterogeneous Clouds.
(iv) Community Clouds –
Community clouds are those types of clouds that are particularly intended to the address requirements of a particular industry. The cloud is characterized by a multi-administrative domain encompassing various deployment models. Therefore these types of clouds are community clouds.
Public clouds are the first type or expression of cloud computing which is formed to public clouds. This cloud is available to anyone with the realization of cloud computing canonical view where the services provided are presented to anyone, at any instant and from anywhere by using the Internet.
In this cloud infrastructure, it is a distributed system from a structural perspective and possibly formed by one or more data centers, on top of which the specific public cloud services provided by the cloud providers are implemented.
Client or user can easily sign-in to this cloud which is provided by a cloud service provider, use its services and enter their personal details securely.
Public cloud platforms-
Public cloud platforms provide the best solution or option for handling high loads on the local infrastructure and provide solutions for reducing IT business costs.
For small organizations or enterprises, they have become an interesting alternative and very beneficial for them for the price point of view.
Some Small organization is able to begin their business without large upfront investments by entirely depending on this cloud infrastructure for their IT requirements. It can be used both to extend the IT infrastructure of enterprise on-demand and to completely replace it.
This cloud provides its services to a large number of users instead of a single one. Multi-tenancy is a basic feature of public clouds. This is required by a user to have a virtual public cloud environment that is possibly isolated, and separated, from the other users.
It is also a basic requirement to offer effective monitoring of user activities, the other QoS(Quality of Service) attributes which are negotiated with users, and ensure the required performance. In this cloud environment, QoS management is an important feature.
As a result, a considerable portion of the software infrastructure is given to monitoring the cloud resources, to bill them on the basis of the contract done with the user and to keep the complete history of cloud usage for each customer. For public clouds, these features are basic since they help providers to provide services to users with full accountability.
Public cloud services-
In this cloud services, it can provide various types of services like infrastructure/hardware, software/applications, and platform as a service. As an example, SalesForce.com is a cloud computing providing software as a service, Google AppEngine is a public cloud providing an application development platform as a service and Amazon liC2 is a public cloud providing infrastructure as a
Finally, we can say that public clouds are large hardware and software infrastructure whose capability is sufficient to meet the requirements of multiple User, however, they suffer from security threats and administrative pitfalls.
Pros and cons of this cloud–
2-Speed of access
5-privacy of data
6-Available at cheap price
These can also be the challenges for this cloud–
2-Some security challenges
3-Limitation of data storages