“Applications such as e-mail, web conferencing, customer relationship management (CRM), all run in cloud.”
Cloud computing term is used to refer to a model of network computing where a program (application) runs on connected server/servers rather than on a local computing device such as a PC, tablet or Smartphone.
As like either the traditional client-server model or older mainframe computing,a user connects with a server to perform a task. The only difference with cloud computing is that the computing process may run on one or many connected computers at the same time, utilizing the concept of virtualization.
That means Cloud Computing refers to manipulating, configuring and accessing the applications online. It offers online data storage, infrastructure and application.
There is no need to install a piece of software on our local PC and this is how the cloud computing overcomes platform dependency issues. Hence, the Cloud Computing is making our business application mobile and collaborative.
There are some assured services and models working behind the scene which are making the cloud computing feasible and accessible to end users.
The working models for cloud computing are as follows:
Deployment models can define the type of access to the cloud, which is how the cloud is located? Cloud can have four types of access: Public, Private, Hybrid and Community.
It allows systems and services to be easily accessible to the general public. May be, Public cloud is less secure because of its openness, for e.g., e-mail.
Private Cloud allows systems and services to be accessible within an organization. It gives increased security because of its private nature.
The Community Cloud allows systems and services to be accessible by group of organizations.
Hybrid Cloud is the mixture of public and private cloud. Wherever, the critical activities are performed using private cloud while the non-critical activities are performed using public cloud.
The Cloud Computing is based on Service Models which are the reference models. These can be divided into three basic service models as below:
Infrastructure as a Service (IaaS)
Platform as a Service (PaaS)
Software as a Service (SaaS)
There are many other service models also all of which can take the form like XaaS that is Anything as a Service. This can be Network as a Service, Business as a Service, Identity as a Service, Database as a Service or Strategy as a Service.
The term Cloud Computing came into existence in 1950 with implementation of mainframe computers, accessible via thin (static) clients. Since then, cloud computing has been evolved from static clients to dynamic ones from software to services.
Some technologies are there which are working behind the cloud computing platforms. That makes cloud computing flexible, reliable and usable. Those technologies are as follows:
SOA( Service-Oriented Architecture )
Grid Computing technology
Utility Computing Technology