Environmental Engineering Reference
In-Depth Information
of the future, nevertheless, autonomic computing
is focused on the most pressing problem facing
the IT industry today: the increased complexity
of the IT infrastructure that typically accompanies
the increased business value delivered through
computing advancements. The problem is con-
tributing to an increasing inability of business to
absorb new technology and solutions.
API (Application Programming Interface). Thus
at the hardware level, resources can be added or
withdrawn according to demand posted through
the interface, while the interface to the user is not
changing. Because some cloud computing envi-
ronments use server and storage grid architecture,
cloud computing is sometimes confused with grid
computing. In theory, cloud-computing is similar
to utility-based computing or traditional outsourc-
ing. There are many benefits to cloud computing
besides the reduction of infrastructure cost and
operational support. Because the infrastructure
resides at the cloud provider, capital expendi-
tures are minimized. This includes data center
real estate, electricity, cooling, server, storage,
network technology procurement, and the cost of
resources to manage the environment. Reducing
time to market on the release of new applications
is also a benefit. Some cloud providers offer a set
of development tools that can reduce the time to
develop new applications from months to weeks.
Cloud services providers realize the efficiencies of
a virtualized environment with resource manage-
ment to maximize resource utilization efficiencies.
There is a growing number of cloud computing
providers. Some of the dominant on the market are
Hewlett-Packard, Microsoft, Sun Microsystems,
Salesforce.com, EMC, Amazon, Google. HP offers
a variety of cloud services; HP's strategy is the
company's entrance into cloud computing with
HP Adaptive Infrastructure as a Service (AIaaS),
which lets customers host applications in HP data
centers optimized for Microsoft Exchange, SAP
applications, and other critical business applica-
tions. Providers such as Google and Amazon offer
cloud-computing solutions for e-mail, collabora-
tion, and other web-related services. Googles
Apps cloud covers services such as email and
collaboration. The tools are available to subscrib-
ers and are completely web-based. Google Apps
offers voice and video chat, calendars, and instant
messaging, a service to store documents, provide
content management and provide secure video
Cloud Computing
Cloud computing is the use of the Internet (cloud)
combined with a variety of computer technologies,
such as software applications, servers, storage
and networking components. Cloud computing
is now being used in a hybrid model, whereby
companies are splitting their workloads between
their own data center and the cloud. A cloud is
a pool of virtualized computer resources. Cloud
computing is resulting from the convergence of
grid computing, utility computing and SaaS (Soft-
ware as a Service) and essentially represents the
increasing trend towards the external deployment
of IT resources, such as computational power, stor-
age or business applications and obtaining them
as services. Cloud computing refers to both the
applications delivered as services over the Internet
and the hardware and system software in the data
centers that provide the services. The data center
hardware and software is what is named a cloud
(Stanoevska-Slabeva & Wozniak, 2010a). When
cloud resources are made available in a pay-as-
you-go manner to the general public, it is called a
public cloud. In public clouds services provider is
the owner and manager, services are accessible by
subscription, and driven by standardization. The
term private cloud refers to internal data centers
of a business or other organization, not made
available to the general public. Private clouds
allow for services defined by company, facilitate
service customization, retain services utilization
control integrity and improve interorganizational
efficiency. In cloud the virtualized services are
