What is Cloud Computing?
Cloud computing is an umbrella term used to
refer to Internet based development and services. The cloud is a metaphor for
the Internet. A number of characteristics define cloud data, applications
services and infrastructure:
·
Remotely hosted: Services or
data are hosted on someone else’s infrastructure.
·
Ubiquitous: Services or data
are available from anywhere.
·
Commodified: The result is a
utility computing model similar to traditional that of traditional utilities,
like gas and electricity. You pay for what you would like.
Software as a Service (SaaS)
SaaS is a model of software deployment
where an application is hosted as a service provided to customers across the
Internet. SaaS is generally used to refer to business software rather than
consumer software, which falls under Web 2.0. By removing the need to install
and run an application on a user’s own computer it is seen as a way for
businesses to get the same benefits as commercial software with smaller cost
outlay. Saas also alleviates the burden of software maintenance and support but
users relinquish control over software versions and requirements. The other
terms that are used in this sphere include Platform
as a Service (PaaS) and Infrastructure
as a Service (IaaS).
Cloud Storage
Several large Web companies (such as Amazon
and Google) are now exploiting the fact that they have data storage capacity
which can be hired out to others. This approach, known as ‘cloud storage’
allows data stored remotely to be temporarily cached on desktop computers,
mobile phones or other Internet-linked devices. Amazon’s Elastic Compute Cloud
(EC2) and Simple Storage Solution (S3) are well known examples.
Data Cloud
Cloud Services can also
be used to hold structured data. There has been some discussion of this being a
potentially useful notion possibly aligned with the Semantic Web , though
concerns, such as this resulting in data becoming undifferentiated , have
been raised.