Cloud Computing is the use of Computing
Resources(Hardware like Hypervisor,Storage,switches & Software like
Virtualization,vlan trafficing , dynamic ip allocation ) that are delivered as
Service over the Network.It's called cloud since all these above mentioned
resources can be scaled on request and based on usage.
Why cloud Computing is
preferred / benefits of Cloud Computing
· Scalability : -The customer doesn't have
to know (and buy) the full capacity they might need at a peak time. Cloud
computing makes it possible to scale the resources available to the
application. A start-up business doesn't have to worry if the advertising
campaign works a bit too well and jams the servers.
· Pay Per Use :- Customers pay only for what they
use. They don’t have to buy servers or capacity for their maximum needs. Often,
this is a cost savings.
· The
cloud will automatically (or, in some services, with semi-manual operations)
allocate and de-allocate CPU, storage, and network bandwidth on demand. When
there are few users on a site, the cloud uses very little capacity to run the
site, and vice versa.
· Reduces Cost :- Because the data centers
that run the services are huge, and share resources among a large group of
users, the infrastructure costs are lower (electricity, buildings, and so on).
Thus, the costs that are passed on to the customer are smaller.
· Application programming interface (API):- Accessibility to
software that enables machines to interact with cloud software in the same way
that a traditional user interface (e.g., a computer desktop) facilitates
interaction between humans and computers
· Virtualization technology allows
servers and storage devices to be shared and utilization be increased.
Applications can be easily migrated from one physical server to another.
Types of Cloud Computing :-
·
Public Cloud
·
Private Cloud
·
Hybrid Cloud
Public Cloud :- In public cloud
applications, storage, and other resources are made available to the general
public by a service provider. These services are free or offered on a
pay-per-use model. Generally, public cloud service providers like Amazon AWS,
Microsoft and Google own and operate the infrastructure and offer access only
via Internet
Private Cloud : - Private cloud is cloud
infrastructure operated solely for a single organization, whether managed
internally or by a third-party and hosted internally or externally.
Hybrid Cloud :
- Hybrid
cloud uses both public and private cloud infrastructure.
Cloud computing
Models
· Infrastructure as a Service (IaaS). IaaS
offers computers - physical or virtual machines - and other
resources like storage so that developers and IT organizations can use to
deliver business solutions.Cloud providers typically bill IaaS services on a
utility computing basis: cost reflects the amount of resources allocated and
consumed.
·
Platform as a Service (PaaS). Pass offers computing
platform typically including operating system, programming language execution
environment, database, and web server. Application developers can develop and
run their software solutions on a cloud platform without the cost and complexity
of buying and managing the underlying hardware and software layers.
· Software as a Service (SaaS). In the SaaS , the
service provider hosts the software so you don’t need to install it, manage it,
or buy hardware for it. All you have to do is connect and use it. SaaS Examples
include customer relationship management as a service.
