Cloud computing is location-independent computing,
whereby shared servers provide resources, software,
and data to computers and other devices on demand.
The concept was coined by John McCarthy in 1960.
The term cloud came into commercial use in the early 1990s generally refers to
large ATM network.
By the 21st century the real concept of “cloud computing” has appeared most
focus was on SaaS.
In 1999 , Saleaforce.com was established by Marc, Parker and his fellows.
IBM extended the concept in 2001.
Cloud computing providers offer their services according to
several fundamental models
Infrastructure as a service (IaaS)
Platform as a service (PaaS)
Software as a service (SaaS)
This is the base layer of the cloud stack.
It serves as a foundation for the other two layers, for their execution. The
keyword behind this stack is Virtualization.
Let us try to understand this using Amazon EC2. In Amazon EC2 (Elastic
Compute Cloud) your application will be executed on a virtual computer
(instance). You have the choice of virtual computer, where you can select
a configuration of CPU, memory & storage that is optimal for your
application. The whole cloud infrastructure viz. servers, routers, hardware
based load-balancing, firewalls, storage & other network equipments are
provided by the IAAS provider. The customer buy these resources as a
service on a need basis.
Infrastructure as a Service (IaaS)
Now you don’t need to invest millions of $$$ to get that
development foundation ready for your developers. The PaaS
provider will deliver the platform on the web, and in most of the
cases you can consume the platform using your browser, i.e.
no need to download any software.
Google app Engine and Window Azure are examples of
Cloud OS. are cloud middleware.
Platform as a Service (PaaS)
• Next generation SaaS promises everything as a
service over the internet.
• Cloud computing started with a similar premise.
• A computing paradigm where there exists a
flexible set of computing resources across the
Cloud Service Providers
Advantages of Cloud Computing
Lower computer costs.
Unlimited storage capacity.
Increased data reliability.
Universal document access
Easier group collaboration
Disadvantages of Cloud Computing
Requires a constant Internet connection.
Features might be limited.
15 Nov 2007, IBM
wants some of that
Web 2.0 mojo. That
is what is behind its
today of Blue Cloud,
a set of “cloud
offerings that will be
available to its
customers in the
first quarter of 2008.
Azure platform is
a flexible cloud
lets you focus on
EC2 allows users
to rent virtual
which to run their
Offers users the
ability to build
and host web
It Provides Tremendous benefits to Companies.
You Pay only for Services that you use.
Cloud computing is now evolving like never
Cloud Computing is the fastest growing part of
IT but still has security issues and somewhat it
But definitely, over a period of time, Cloud
Computing will become the most promising
technology in next few years.