Define the Cloud Computing Landscape
Beginning of this article let some basic inquiries about Cloud computing. What is cloud computing? What are the cloud services? What is a cloud site? What does the cloud file storage mean? How is cloud computing used? What is SaaS service for B2C and B2B sales? What are SaaS ERP and SaaS CRM systems and solutions? What cloud computing models are used to develop web applications? What are Modern data centers, on the basis of which SaaS, PaaS, and IaaS are created?

IT Support Services experts define the Cloud as an innovative model or concept of an IT infrastructure organization, which consists of distributed and shared configurable hardware and network resources, as well as software, deployed on remote (cloud) data centers of providers (like IT Companies in Birmingham). That is, a cloud is a new approach to the organization of IT infrastructure.

Cloud computing is a model for providing remote access to shared computing resources that are physically distributed on many remote devices that form the so-called cloud and it is a model of providing scalable computing resources to a consumer as a service over the Internet. Cloud technologies are a model for presenting managed IT services over the Internet to a consumer.

Cloud Computing Definition - a model of enabling ubiquitous and convenient network access on demand to a pool shared of configurable computing resources (networks, servers, storage, applications, and services) that can be rapidly made available and released with minimal management effort or interaction with the provider (supplier). This cloud model is represented (described) by five main characteristics, three service models and four deployment models.

Self-service on demand- The consumer, as necessary, automatically, without interaction with each service provider, can independently determine and change the computing capacity, such as server time, data storage capacity.

Wide (universal) network access- Computing capabilities are available over long distances over the network through standard mechanisms, which promotes the wide use of heterogeneous (thin or thick) client platforms (terminal devices).

Pooling resources- Configurable computing resources of the supplier are combined into a single pool for sharing distributed resources by a large number of consumers.

Instant resource elasticity (instant scalability)- Cloud services can be quickly provided, expanded, compressed, and released based on customer needs.

Measured service (accounting of consumed service and the ability to pay for services that were actually used)- Cloud systems automatically manage and optimize the use of resources by taking measurements.

If the model (concept) of providing distributed and shared configurable computing resources corresponds to the above characteristics, then this is cloud computing.

Service Cloud Computing Models:

Software as a Service ( SaaS ) - In this cloud computing provision model, the consumer uses the provider applications running in the cloud infrastructure, which are accessible to the client through the interface (web browser) or the program interface. Consumers cannot manage and control the underlying cloud infrastructure, including the network, servers, operating systems, data warehouses, or even change the settings of a particular application.

Platform as a Service ( PaaS ) - The cloud computing model, in which the consumer gets access to the use of a software platform like operating systems, DBMS, application software, software development tools, and testing tools. In fact, a consumer rents a computer platform with an installed operating system and specialized tools for developing, hosting and managing web applications. The consumer does not control the core cloud infrastructure, including the network, servers, operating systems, or data warehouses, but it manages the deployed applications and possibly environment configuration settings.

Infrastructure as a Service ( IaaS ) - In this model, the consumer can manage processing and storage facilities, as well as other fundamental computing resources (virtual servers and network infrastructure), on which he can independently install operating systems and application programs for his own purposes. In essence, the consumer leases abstract computing power (server time, disk space and bandwidth of network channels) or uses the services of IT infrastructure outsourcing. The consumer does not manage the core cloud infrastructure but manages the operating systems, storage, and applications deployed by it.

Cloud computing deployment models:

Private cloud (private cloud) - an infrastructure designed to use cloud computing in a single organization.
Community cloud- This is a cloud infrastructure that is intended for the exclusive use of cloud computing by a specific community of consumers from organizations that solve common problems.
Public cloud (public cloud) - infrastructure designed for the free use of cloud computing by the general public.
Hybrid cloud- It is a combination of various cloud infrastructures (private, public or communities) that remain unique objects, but interconnected by standardized or private technologies that provide the ability to exchange data and applications.

Based on the above definition of cloud computing, IT Support Birmingham experts have defined cloud services as a multi-layer model consisting of layers: IaaS, PaaS, SaaS. The basis or foundation of cloud services is the physical infrastructure, i.e. servers, storages, networks and system software of the Cloud data center (cloud data center) or a network of interconnected cloud Datacenters.