What is Cloud Computing?
Cloud Computing, simply known as ‘Cloud’ is defined as a pool of computing resources hosted over the Internet. Cloud Computing is an infrastructure that enables sharing of computing resources that are otherwise limited and inaccessible to public.
These resources in general include more storage space, more computing power, servers, data centers and on-demand access to applications provided by third-parties for individual users as well as enterprises.
How Cloud works’ -Explained with video
Resources are not only shared by multiple users at the same time but also shared through dynamic allocation as per the demands. As an example, a cloud serving in the Asian region can allocate specific resources (e.g. memory space) to users during Asian business hours and the same or different resource (e.g. Email) can be allocated to Australian users during their business timings. This results in optimized and effective use of resources while hiding other network services and resources from the users in a cloud.
To a user, services are provided only for the duration of time he has paid. Thus, cloud computing also serves as an efficient economic model for users who can otherwise not afford expensive licenses for software that may be required only for a limited period of time. Moreover, it lessens the financial and environmental burden in terms of less energy required for air-conditioning and space for server racks.
Although the concept of cloud computing has evolved over time since its inception, it is generally classified in to three types: Software-as-a-service (SaaS), Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS).
Also learn cloud types based on services
How Cloud Computing Works in Different Applications?
A cloud can be divided in to two sections: A front-end layer and back-end layer both connected through internet. Front end is that of end users or clients that consumes cloud services. This end consists of end user computer and the application to access cloud service.
Different cloud services can have different application interfaces to interact with the cloud.
For example, accessing email through web browsers such as Chrome has a different interface to that of Microsoft Outlook computer-based email.
At the back-End lies the core functioning of a cloud computing system. It deploys high speed computing devices usually used by military, several other special-purpose and general-purpose computers networked together, servers and data centers that make up the cloud. A main server acts as an administrator that looks after the smooth working of the cloud by monitoring traffic flows and catering to the client demands. This is made possible using different protocols and special software called Middleware.
A middleware allows communication between computers in a network within the cloud. Since, servers usually don’t run to its full capacity, a technique called Server virtualization is deployed that optimizes servers’ performance to its full capacity. This way, the need for more physical servers is reduced.
You can read all about cloud computing basics here.
If number of clients in a cloud increase, so does the space requirement to store new clients’ information. For a typical cloud computing system, as minimum as twice the amount of storage space is required to store clients’ data.
This is because of the possibility that servers crash or fail due to a number of reasons. This could include power outage or a link going down between a computer and server. In that case, cloud must maintain a copy of information of all its clients’. The administrative server can access this information through back up servers in order to keep the cloud services up.
To start using a cloud service, a user generally logs in to a public or enterprise portal and orders the desired cloud services. This procedure includes payment through credit card and other specifications such as period of time user plan on to utilize the service.
After payment is validated through Business System Services (BSS), the request is forwarded through the Operating System Services (OSS). The user then receives the credentials to access the requested services for the duration of time he has paid with monthly invoices or according to the consumption.
Rules, laws and policies have been formulated to address these privacy issues. Various encryption techniques are also used to secure data before it is stored in the cloud. Private cloud acts as a better security solution giving more control to user over its data. But then, that is compromised with low cost and flexibility offered in the public cloud.
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