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cloud computer
Cloud computing
INTRODUCTION
Definition: Cloud computing
is a term that applies to applications and data storage that are delivered over
the Internet or via wireless technology. The individual user's device (i.e.
computer, cell phone, etc.)
The phrase is often used in reference to network-based services, which appear to be provided by real server hardware, and are in fact served up by virtual hardware, simulated by software running on one or more real machines. Such virtual servers do not physically exist and can therefore be moved around and scaled up or down on the fly without affecting the end user, somewhat like a cloud.
In common usage,
the term "the cloud" is essentially a metaphor for the Internet.[2]
Marketers have further popularized the phrase "in the cloud" to refer
to software, platforms and infrastructure that are sold "as a
service", i.e. remotely through the Internet. Typically, the seller
has actual energy-consuming servers which host products and services from a
remote location, so end-users don't have to; they can simply log on to the
network without installing anything. The major models of cloud computing
service are known as software as a service, platform as a service, and infrastructure as a service. These cloud
services may be offered in a public, private or hybrid network.[3] Google,
Amazon, Salesforce,
and Microsoft Azure are some well-known cloud vendors.
The popularity
of the term can be attributed to its use in marketing to sell hosted services
in the sense of application service provisioning that run client server
software on a remote location
.Cloud computing
refers to the use of computing resources, those being hardware and/or software)
that reside on a remote machine and are delivered to the end user as a service
over a network, with the most prevalent example being the internet. By
definition, a user entrusts his data to a remote service, on which has limited
to no influence.
Security
As cloud
computing is achieving increased popularity, concerns are being voiced about
the security issues introduced through adoption of this new model.The
effectiveness and efficiency of traditional protection mechanisms are being
reconsidered as the characteristics of this innovative deployment model can
differ widely from those of traditional architectures.
An alternative
perspective on the topic of cloud security is that this is but another,
although quite broad, case of "applied security" and that similar
security principles that apply in shared multi-user mainframe security models
apply with cloud security.
access, data
segregation, privacy, bug exploitation, recovery, accountability, malicious
insiders, management console security, account control, and multi-tenancy
issues. Solutions to various cloud security issues vary, from cryptography,
particularly public key infrastructure (PKI), to use of multiple cloud
providers, standardisation of APIs, and improving virtual machine support and legal support.
The relative
security of cloud computing services is a contentious issue that may be
delaying its adoption.[133] Physical control of the Private Cloud equipment is
more secure than having the equipment off site and under someone else's
control. Physical control and the ability to visually inspect data links and
access ports is required in order to ensure data links are not compromised.
Issues barring the adoption of cloud computing are due in large part to the
private and public sectors' unease surrounding the external management of
security-based services. It is the very nature of cloud
computing-based services, private or public, that promote external
management of provided services. This delivers great incentive to cloud
computing service providers to prioritize building and maintaining strong management
of secure services. Security issues have been categorised into sensitive data
Categories
There are mainly
four models of cloud computing:
Infrastructure as a Service (IaaS)
Platform as a Service (PaaS)
Software as a Service (SaaS)
Network as a Service (Naas)
Advantages
1.Cost
Efficiency
This is the
biggest advantage of cloud computing, achieved by the elimination of the
investment in stand-alone software or servers. By leveraging cloud’s
capabilities, companies can save on licensing fees and at the same time
eliminate overhead charges such as the cost of data storage, software updates,
management etc.
2.Backup and
Recovery
The process of
backing up and recovering data is simplified since those now reside on the
cloud and not on a physical device. The various cloud providers offer reliable
and flexible backup/recovery solutions.
3.Increased
Storage Capacity
The cloud can
accommodate and store much more data compared to a personal computer and in a
way offers almost unlimited storage capacity.
4.Smaller
learning curve
Cloud applications
usually entail smaller learning curves since people are quietly used to them.
Disadvantages
1.Limited
control and flexibility
Since the
applications and services run on remote, third party virtual environments,
companies and users have limited control over the function and execution of the
hardware and software.
2.Dependency and
vendor lock-in
One of the major
disadvantages of cloud computing is the implicit dependency on the provider.
This is what the industry calls “vendor lock-in” since it is difficult, and
sometimes impossible.
Conclusion
Despite its
disadvantages and the fact that it is still in an infant age, cloud computing
remains strong and has great potential for the future. Its user base grows
constantly and more big players are attracted to it, offering better and more
fine tuned services and solutions. We can only hope that the advantages will
further grow and the disadvantages will be mitigated, since cloud computing
seems to have made IT a little bit easier. Happy cloud computing!
Cloud computing offers benefits
for organizations and individuals. There are also
privacy and security concerns. If
you are considering a cloud service, you should
think about how your personal
information, and that of your customers, can best be
protected. Carefully review the
terms of service or contracts, and challenge the
provider to meet
your needs.
Benefits
1.Scalability
Your business
can scale up or scale down your operation and storage needs quickly to suit
your situation, allowing flexibility as your needs change.
2.Business
continuity
Protecting your
data and systems is an important part of business continuity planning. Whether
you experience a natural disaster
3.Access to
automatic updates
Access to
automatic updates for your IT requirements may be included in your service fee.
Depending on your cloud computing service provider
Characteristics
Cloud
computing exhibits the following key characteristics:
- Agility improves with users' ability to re-provision technological infrastructure resources.
- 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. Cloud computing systems typically use Representational State Transfer (REST)-based APIs.
· Virtualization technology allows
sharing of servers and storage devices and increased utilization. Applications
can be easily migrated from one physical server to another.
· Multitenancy
enables sharing of resources and costs across a large pool of users thus
allowing for:
- centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)
- peak-load capacity increases (users need not engineer for highest possible load-levels)
- utilisation and efficiency improvements for systems that are often only 10–20% utilised.
· Reliability improves with the use of
multiple redundant sites, which makes well-designed cloud computing suitable
for business continuity and disaster
recovery.
· Scalability and elasticity via dynamic
("on-demand") provisioning of resources on a fine-grained,
self-service basis near real-time(Note, the VM startup time varies by VM type,
location, os and cloud providers), without users having to engineer for peak
loads
· Performance is monitored, and consistent
and loosely coupled architectures are constructed using web
services as the system interface
Maintenance of cloud computing
applications is easier, because they do not need to be installed on each user's
computer and can be accessed from different places.
Types:-
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. Undertaking a private cloud project requires a significant level and degree of engagement to virtualize the business environment, and requires the organization to reevaluate decisions about existing resources. When done right, it can improve business, but every step in the project raises security issues that must be addressed to prevent serious vulnerabilities.Self-run data centers are generally capital intensive. They have a significant physical footprint, requiring allocations of space, hardware, and environmental controlsPublic cloud
A cloud is called a "public cloud" when the services are rendered over a network that is open for public use. Technically there may be little or no difference between public and private cloud architecture, however, security consideration may be substantially different for services (applications, storage, and other resources) that are made available by a service provider for a public audience and when communication is effected over a non-trusted network. Generally, public cloud service providers like Amazon AWS, Microsoft and Google own and operate the infrastructure and offer access only via Internet (direct connectivity is not offered).Community cloud
Community cloud shares infrastructure between several organizations from a specific community with common concerns (security, compliance, jurisdiction, etc.), whether managed internally or by a third-party and hosted internally or externally. The costs are spread over fewer users than a public cloud (but more than a private cloud), so only some of the cost savings potential of cloud computing are realized.Hybrid cloud
Hybrid cloud is a composition of two or more clouds (private, community or public) that remain unique entities but are bound together, offering the benefits of multiple deployment models. Hybrid cloud can also mean the ability to connect collocation, managed and/or dedicated services with cloud resources.Gartner, Inc. defines a hybrid cloud service as a cloud computing service that is composed of some combination of private, public and community cloud services, from different service providers.A hybrid cloud service crosses isolation and provider boundaries so that it can’t be simply put in one category of private, public, or community cloud service. It allows one to extend either the capacity or the capability of a cloud service, by aggregation, integration or customization with another cloud service.
Distributed cloud
Cloud computing can also be provided by a distributed set of machines that are running at different locations, while still connected to a single network or hub service.How Cloud Computing Works
The goal of cloud computing is to apply traditional supercomputing, or high-performance computing power, normally used by military and research facilities, to perform tens of trillions of computations per second, in consumer-oriented applications such as financial portfolios, to deliver personalized information, to provide data storage or to power large, immersive computer games.
To do this, cloud computing uses networks of large groups of servers typically running low-cost consumer PC technology with specialized connections to spread data-processing chores across them
Features
Focus on your code
Let Google worry about database administration, server configuration, sharding and load balancing. With Traffic Splitting, you can A/B test different live versions of your app. Multitenancy support lets you compartmentalize your application data.Multiple storage options
Choose the storage option you need: a traditional MySQL database using Cloud SQL, a schemaless NoSQL datastore, or object storage using Cloud Storage.Powerful built-in services
App Engine makes you more productive by eliminating the need to write boilerplate code. Managed services, such as Task Queues, Memcache and the Users API, let you build any application.Deploy at Google scale
Some of the world’s most popular web services are built on our platform. You can scale up to 7 billion requests per day and automatically scale down when traffic subsides.Uses:-
1.Agile Development on Cloud
Agility in business operations comes with effective and efficient tools that help in constructing a strong and construing business or work environment. This is due to the fact that cloud technology is built on norms like understanding service-level agreements or SLAs, developing various strategies to understand the business as a whole and then improvising as well as analyzing the steps necessary for keep the businesses running smoothly.2.Cloud, Cost-Effective in Nature
If you haven’t opted for cloud technology till date, don’t lag behind and pop into the cloud market to enjoy a cost-effective business environment. As mentioned above that cloud promotes device independence, the cost of hardware and software automatically cuts short. Although, the initial expense of deploying cloud architecture is there, but that also focuses on pay for what you use model.3.Disaster Recovery Plan Help to Restore Data Quickly on Cloud
For every cloud to be a successful one, pre-configured disaster recovery plan is must. Cloud disaster recovery plan works automatically at the time a server or data crashes and help in restoring at the earliest. Incorporating such applications makes cloud an efficient platform for managing IaaS, PaaS and SaaS competitively.4.Organizations Experience Device Independence
When we say that by putting everything on cloud can reduce your worry of keeping a track of hardware and software devices, we probably want to make your existing physical world into a virtual one. With managed cloud services you don’t have to bother about what’s going on in your in-house IT premises.Applications:-
Software-as-a-Service
(SaaS)
Software-as-a-Service commonly refers to applications delivered to the end user through a web browser or any other web-rich client. Examples include Microsoft OfficeLive.
Platform-as-a-service
(PaaS)
Platform-as-a-Service provides more customisation room, for example, for a developer to acquire a bespoke platform (such as operating system, software, and libraries) that is usually used to carry out a very specific task. Examples include Google AppEngine, SalesForce VMforce, and Joyent Accelerator.
Infrastructure-as-a-Service provides maximum control where a computing infrastructure can be assembled from the operating system upwards. Examples include Amazon EC2, Eucalyptus Community Cloud, and IBM Cloudburst.
Deployment of cloud services:
Cloud services are typically made
available via a private cloud, community cloud,
public cloud or hybrid cloud.
Generally speaking,
services provided by a public cloud are
offered over the
Internet and are
owned and operated by a cloud provider. Some examples include
services aimed at the
general public, such as online photo storage services, e-mail
services, or social
networking sites. However, services for enterprises can also be
offered in a public
cloud.
In a private
cloud, the cloud infrastructure is operated solely for a specific
organization, and is
managed by the organization or a third party.
In a community
cloud, the service is shared by several organizations and made
available only to
those groups. The infrastructure may be owned and operated by the
organizations or by a cloud service
provider.
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