What is Cloud Computing?
Instead of buying and maintaining network, server, storage,
applications and supporting equipments at our buildings, let the providers
maintain them for us at their location. By having stringent legal and commercial
contracts, these facilities can be used on demand basis or throughout the year.
Why Cloud Computing?
Say for example, a company has few pay roll servers to run
pay roll for their employees. The pay roll servers and applications are used
primarily during the pay roll run time and remaining days, they stay idle.
During the idle time, the company still spends money for space, electricity, backup,
monitoring and resources. By using the pay roll service on subscription basis
for the payroll run time with the Cloud provider, the money spent for idle time
will be saved. The Cloud provider use the Servers for some other purpose during
that time.
What are Characteristics of Cloud Computing?
On-demand self-service
A consumer unilaterally provisions computing resources as
needed automatically without human interaction (Example: Virtualization)
Resource pooling
Computer resources are pooled to transparently serve
multiple consumers.
Rapid elasticity
Capabilities can be rapidly and elastically provisioned,
in some cases automatically to quickly scale out and rapidly released to
quickly scale in.
Measured service
Cloud systems automatically control and optimize resource
use via a metering capability. Resource usage can be monitored, controlled, and
reported providing transparency for both the provider and consumer of the
service.
Broad network access
Capabilities are accessed over the network and accessed
through standard mechanisms that promote heterogeneous thin or thick client
platforms.
What are the Service Models of Cloud Computing?
Software as a Service (SaaS)
With Software as a Service (SaaS), service consumers get
their software applications from the service provider. The consumer uses the
software as an application while the provider manages the underlying software
and infrastructure. Applications are often delivered to the customer via a web
browser in SaaS architecture (Example: salesforce.com)
Platform as a Service (PaaS)
In Platform as a Service (PaaS), the consumer uses
programming languages and tools from the provider as an application development
and deployment platform. The platform may include databases and middleware in
addition to application development tools. Virtualized and grid computing are
often a key basis for PaaS architectures.
Infrastructure as a Service (IaaS)
With Infrastructure as a Service (IaaS), the provider
manages the underlying physical cloud infrastructure (operating system,
network, storage) while consumers deploy and run their own application software
and provision resources as necessary. Virtualization software is integral to
IaaS architectures.
What are the Cloud Deployment Models?
Private Clouds
It is for an exclusive use by a single organization and
typically controlled, managed and hosted in private data centers. The hosting
and operation of private clouds may also be outsourced to a third party service
provider, but a private cloud remains for the exclusive use of one
organization.
Public Clouds
For use by multiple organizations (tenants) on a shared
basis and hosted and managed by a third party service provider (Example:
Amazon, RackSpace)
Community Clouds
For use by a group of related organizations who wish to
make use of a common cloud computing environment. For example, a community
might consist of the different colleges of a University, all the universities
in a given region, or all the suppliers to a large manufacturer.
Hybrid Clouds
When a single organization adopts both private and public
clouds for a single application in order to take advantage of the benefits of
both. For example, an organization might run the steady-state workload of an
application on a private cloud, but when a spike in workload occurs, such as at
the end of the financial quarter or during the holiday season, they can burst out
to use computing capacity from a public cloud, then return those resources to
the public pool when they are no longer needed.
Oracle Cloud computing Strategy
Oracle has two Cloud Service Models
Platform as a Service (PaaS)
Oracle PaaS is based on Oracle WebLogic Server,
Coherence, Tuxedo and JRockit as a foundation. On the top of the foundation,
the PaaS also includes Oracle Fusion Middleware components such as Oracle SOA
Suite, Oracle BPM Suite, Oracle Identity Management and Oracle Web Center. For
data support, Oracle Database and RAC are used.
Infrastructure as a Service (IaaS)
Oracle IaaS is based on Sun’s Open Storage, Oracle
Solaris, Oracle Enterprise Linux and Oracle VM for virtualization, Sun SPARC and
x86 servers (Present Oracle Exalogic and Exadata). The above
PaaS is hosted by this IaaS.
Both the Oracle PaaS and Oracle IaaS are managed by
Oracle Enterprise Manager (OEM), which provides integrated systems management
from applications to disk across the complete cloud deployment lifecycle.
The below diagram explains the Oracle Cloud Service Model
