Cloud Delivery and Hosting Models - Deploying and Managing a Cloud Infrastructure - page 161

Community

A community cloud is a type of cloud computing deployment model that is used between a
selective group of users or organizations. A community cloud is generally provisioned using
public cloud technologies, but it can also be delivered using the private or even the hybrid
model. The community cloud can consist of a number of individuals or organizations working
on a joint project and/or collaborating knowledge and data among each other.
The following types of organizations are suited for the community cloud model:

Scientific research organizations that use the community cloud to perform work on
joint projects, research, and experiments

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Government organizations using SaaS application to perform business processes that
are deployed and delivered through a community cloud

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Educational institutions sharing a community cloud to perform research and/or share
knowledge

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On-Premises vs. Off-Premises Hosting

The on-premises versus off-premises debate is nothing new. It existed even before the
advent of real cloud computing. Way back in the 1961, John McCarthy of artificial intel-
ligence (AI) and Lisp fame suggested during a speech given at MIT's centennial that utility
computing would become an ideal business model. Following that notion, in the age of
mainframes and large supercomputers, computing was mainly done online through early
networking technologies. Companies bought computing time from mainframe providers,
and users would sit behind extremely slow terminals for hours imputing data and creating
reports. It was very labor intensive and costly. This went on for more than a decade until
personal computers became powerful enough, with larger storage capacities and cheaper
price points, to allow real on-premises computing. These PCs were still extremely slow and
expensive compared to today's offerings, but they offered more value compared to the all-
online utility computing alternative at that time. Remember your PCs from the '80s? They
were essentially as powerful as modern calculators with the price point of high-end work-
stations. But at that time, they opened up a whole new world of personal computing possi-
bilities, even though they were still considered underpowered at the same time.
As the advantages of computer technology in the '90s pushed businesses to adapt and
change or be at a disadvantage, enterprise computing began to take hold. Data centers were
being built across the industry to allow businesses to make use of computer technology for
business operations. This was now the time of on-premises computing, where large data
centers became the core drivers of business processes and where data and data security, as
always, became a powerful weapon for large corporations. Then came the new millennium
with its focus on online communication, global networking, and the Internet, which changed
the landscape once again.