What is Cloud computing ?
Cloud computing is practice of using computing resources hosted on the Internet. These services are offered from variousdata centers all over the world, which are referred to as the “cloud.”The word “cloud” represents the intangible, yet universal nature of the Internet. Just to give you an example you might have some media content on facebook like pictures and some of these media contents might be stored in different locations by Facebook but you can still access them over the internet without knowing the location where that media content is stored. Cloud service model is composed of five essential characteristics three service models and four deployment methods
This cloud service allows users to obtain, configure and deploy cloud services automatically without requiring human interaction with each service provider.
Broad network access
Broad network access refers to cloud resources hosted in a private cloud network (securely protected resource) that are available for access from a wide range of devices, such as smartphones, PCs, Macs and tablets. These resources are also accessible from a wide range of locations that offer online access.
The provider’s computing resources are pooled to serve multiple users using a multi-tenant model, with different physical and virtual resources dynamically assigned according to consumer demand.C loud computing promotes location independence, the customers generally have no control or know over the exact location of the provided resources but may be able to specify location at a higher level of abstraction (e.g., country, state, or data center). Examples of resources include storage, processing, memory, and network bandwidth.
The capabilities of this cloud service can be elastically provisioned and released automatically, this cloud feature can scale up rapidly outward and inward commensurate with Business demand. To the users, the capabilities available for provisioning often appear to be unlimited and can be appropriated in any quantity at any time.
Cloud services automatically control and optimize resource use by implementing a metering capability appropriate to type of service that it is used for. Resource usage can controlled, monitored and reported.
Cloud service models
Software as a Service (SaaS)
This means the service provided to the user is to use cloud service provider’s application running on cloud infrastructure. The applications can be accessed from various client devices such as web browser or computer application interface. the users do not have to manage or control the underlying cloud infrastructure including servers,networks, storage and operating system.
Platform as a Service (PaaS)
The functionality provided to users is to implement user created application using a programming language, libraries, services and tools provided by cloud service provider. The users don’t need to worry about managing the
cloud infrastructure but they have control deployed software application and its configuration.
Infrastructure as a Service (IaaS)
The cloud service functionality given to the user is to provision processing, storage, networks, and other fundamental computing resources where users are able to deploy and run arbitrary software, which can include operating systems and applications.
the users have no control over the management and maintenance of cloud infrastructure but users have control over operating systems, storage, and deployed applications.
The deployment of this cloud infrastructure is provisioned for exclusive use by single organization including multiple users. this service can be privately owned and managed by an organization, a third party or combination of the two.
The cloud infrastructure is deployed for exclusive use by a specific community of consumers from various organizations that have shared concerns (e.g., mission, security requirements, policy, and compliance considerations).
This cloud service deployment can be managed internally or by a third-party and hosted internally or externally. The service costs are spread over fewer users than a public cloud (but more than a private cloud), so only some of the cost savings potential of cloud computing are realized
The cloud infrastructure is deployed for open use by the general public. It may be owned, managed, and operated by a business, academic, or government organization, or some combination of them. It is implemented on the premises of the cloud provider.
The deployment of hybrid cloud service is the composition of at least one private cloud and at least one public cloud. A hybrid cloud is typically offered in one of two ways, a vendor has a private cloud and forms a partnership with a public cloud provider, or a public cloud provider forms a partnership with a vendor that provides private cloud platforms.