Introduction into cloud computing or what is a cloud
Cloud computing - is a popular term that is used wherever possible. What is cloud computing and what it offers?
Cloud - a collection of IT-resources such as computing resources (servers), disk space (data storage), network equipment, communication channels, software (operating systems, databases, application software). According to the concept of cloud computing, these resources are allocated for the end user immediately on demand.
Typically, the user gets access to the resources allocated for him by using the Internet. This is typical for a public cloud. A public cloud is built by a compony to provide services to external customers. The company owner of the cloud is responsible for its performance, availability of the necessary resources, manages all processes associated with maintaining access to the cloud. The consumer only uses the resources of the cloud.
There is also a private cloud - a cloud that is created by the company for its own needs and is not available to external customers. Typically, these clouds are in large companies, which have sufficient funds to build a cloud, and which have a complex structure of internal divisions, with changing needs in computing resources.
A Hybrid cloud - a cloud based upon use of both private and public clouds. For example, the company has its own private cloud with a certain resource, and in excess of the available resource, a resource of public clouds.
What offers a cloud?
The cloud provides the flexibility that is missing when using the traditional approach to IT-infrastructure. To increase capacity of servers you do not have to wait for the delivery of additional equipment, no need to buy new licenses or to increase the support staff. Everything happens quickly and on demand. But more than that, you can also reduce the resources consumed. For example, the company has a new project, under which purchased the equipment, software, people are hired, and then the project is frozen for six months. As a result, the company has spent money on equipment and software, which will be idle for six months. Moreover, for the six months hardware and software can get out of date. Using cloud computing, the company pays only for the resources it consumes at a particular point in time. This approach is called pay as you go.
Options for providing cloud services.
The transformation of IT into a service greatly simplifies and organizes the process of using IT-technologies. Many companies consider IT as a service, even within a single company which helps successfully conclude and implement agreements between business and IT.
Cloud is also a service that can be provided in different ways.
IaaS - Infrastructure as a Service. In this case, the cloud provides an entire infrastructure - network equipment, storage, servers, operating systems, control systems. You get your own virtual data center, which is flexibly scaled like everything in a cloud.
PaaS - Platform as a Service. The level of abstraction above the IaaS. It provides a platform (operating system, database, application server load balancing, etc.) for applications.
SaaS - Software as a Service. A ready to use application is provided to end user through a Web interface. An example of such service is Microsoft Office 365.
Many believe that the term "cloud computing" is just a marketing term of companies which provide these services because there is no brand new technological solutions. But at the same time, there is a new approach to the way of providing this information technology as a service, which gives a business flexible, high-quality prompt solutions that allow companies to successfully respond to market changes.