No two clouds are the same. At cloud computing there are different models. Public clouds, private clouds, hybrid clouds and community clouds differ according to who the services come from, how they are organized and which target group they target.
One for all: Public Cloud
A public cloud, also known as a public cloud, is made freely accessible and openly available to a large public by a provider via the network. The respective providers, known here primarily as providers such as Amazon, Google or Microsoftprovide the infrastructure of their cloud. Access for users via the Internet usually takes place without any special restrictions. In the case of a public cloud, the user has neither insight nor control over exactly where or how the provider operates. It is also important to know that all users of a public cloud access the same pool for the infrastructure. The configuration as well as the guaranteed security and the variants available to the user in the cloud are limited to the essentials.
In return, users of a public cloud benefit from mass business. This is because the respective provider passes on its financial expenditure for the infrastructure to a large number of users. Each individual pays the low costs in a pay-as-you-go system. If only because of their almost unlimited number of servers, public clouds are also extremely reliable. If one component fails, the respective cloud can access other components in the shortest possible time.
Closed Company: Private Clouds
Private clouds are services operated and organized by companies or organizations themselves. Often companies, authorities or institutions prefer these private clouds for data protection reasons or because of the security of their IT, to which they grant access exclusively to their own employees. Authorized users can also be customers, business partners or suppliers. Private clouds can be designed and hosted internally. In this case, the IT is located within the own organisation and can be accessed via the internal network, the intranet. External hosting is also possible. External clouds, i.e. clouds hosted by a specialized third party, are just as exclusive as internal private clouds and thus offer the security that public clouds lack. In return, the costs of private clouds are higher. Providers of external hosting are specialized companies and increasingly also telecommunications companies.
The mix: Hybrid Clouds
If public and private clouds are combined, we speak of hybrid clouds. In this hybrid form, certain services can run on the Internet with public providers on the one hand, while other applications remain within the company for data protection reasons. The challenge here is to separate business processes into those that are critical or non-critical in terms of data protection. The advantages of the hybrid cloud are, in addition to the flexible use of all resources, the good scalability and the lower costs compared to the pure private cloud. However, the management of the cloud is associated with higher effort. Also the risk that Data into the wrong cloud is higher. In addition, the hybrid cloud has a greater administrative overhead.
Good for projects: Community Cloud
Community Clouds are a special case. In this concept, organizations or companies in an industry connect to each other via their private clouds to form a cloud. All members of the community have access to this community cloud. These clouds are ideal wherever organizations or companies have similar or identical tasks for which they want to use a common infrastructure. The users are connected by the same requirements, for example in terms of compliance with special security regulations or legal provisions, for example with regard to data security and data protection. Community clouds are often not limited to providing infrastructure and services, but are often closely aligned with users' business processes.
