Cloud Computing: An introduction

You might have come across the term cloud computing or simply  the cloud  many times, in the recent past. Just like the system of interconnected computers more popularly known as Internet, cloud computing is also becoming our companion.  Here are the basics of cloud computing for the late entrants. 

If your office is a small one, you might have noticed that data is stored in a single main computer called server and that the individual PCs are connected to this server. Data from server can be fetched only by those employed in your office or organization. Imagine you are using the  e-mail services of  Google or   Yahoo. Here, the e-mails are not saved in your PC or in a server on which you have direct control. It is served in a remote server. Unlike the officer server, which is a dedicated one for your organization alone, the server of Google or Yahoo caters to millions across the globe who do not have any control over the functioning of the server.  This is an example of cloud computing.  Suppose, your company is a new one and that it cannot afford the investment for a dedicated server. In that case, the company can utilize the service of server vendors  for a rent. Just like the e-mail account allows log in facility to account holder only,  data stored in shared server is made available only to the authorized persons.  The interesting point to note is that the server may not be dedicated one for you alone, and your competitor may also be storing data in the same server. 

Cloud Computing -Definition

Cloud computing is one in which large number of remote servers are networked to ensure centralized data storage. The centralized data is made available through online access control to the persons authorized to access the data.  Cloud computing is thus sharing of resources to minimize cost impact. It uses cetralised infrastructure and shared services. The vendor allocates the available resources to maximum number of clients to optimize effectiveness and ensure maximum utilization.  In simple terms, cloud computing is a type of internet based computing where in different components like servers, applications, programmes etc are made available to an organization’s computers  through internet. 
 

Cloud Computing- Components

The cloud Computing has three components:
1.    Client computers – The devices that the end user uses to interact with the cloud.
2.    Distributed servers – Servers may be located in different geographies, but are properly interconnected and servers may be feeling as if they are neighbors.
3.    Data centre – The centre where servers with applications or data is physically located.

Cloud Computing- Types of services

SaaS– Software as a Service- Required software, operating system and network are made available to the client by the vendor. 
PaaS– Platform as a Service- Operating system and network only are made available to the client. 
IaaS– Infrastructure as a Service- Network alone is provided to the client.

 Cloud Computing – Different categories

Public Cloud–  The services and infrastructure are provided over the internet to reduce cost, but the services  are more vulnerable compared to private cloud. 
Private Cloud– The infrastructure and services are provided on private network. It is more secure with more control compared to public cloud, but expenses are on higher side.
Hybrid (Combined) Cloud– Includes public or private options. Things are spread over multiple providers. 
Community Cloud– Services are shared among similar groups or organizations having common purposes, like accounting firms or regulators. 

By John CS