Page 85 - Cloud Essentials

CERTIFICATION SUMMARY

Cloud solutions use technology to serve varying business needs. Private
clouds run on computing infrastructure owned by an organization, and the
private cloud services are for exclusive use by that organization. Cloud
services can be metered for departmental chargeback.
Public clouds offer IT services to all organizations and Internet users, and

these users normally have a monthly subscription fee (essentially, “pay as
you go”). Hybrid cloud combine private and public clouds. For example, a
company might use its private cloud during normal business activity and use
public cloud services to handle additional business activity.
SaaS allows end users to access productivity software using a web
browser, anytime, from a wide range of devices. PaaS allows software
developers to quickly create and test applications or web services.

IaaS offers computing infrastructure resources such as virtual servers,
cloud storage, cloud networks, and so on, to be rented as needed by cloud
customers. Virtualization hides physical hardware from a running guest
operating system so that multiple virtual machines can run concurrently on a
single physical server. This is required for rapid provisioning and
deprovisioning of cloud IaaS services, and it is much quicker than

traditional server procurement.
Because cloud services are delivered over a network (such as the
Internet), fast and redundant network connections should be considered; the
network connection presents a single point of failure. Cloud providers
ensure there is not a single point of failure with their configurations; service
availability will be outlined in the SLA.
Self-service is a cloud characteristic that allows cloud subscribers to use

a web portal to add or remove cloud service components, such as adding
new email accounts for newly hired employees or adding a new virtual
server to handle an increase in business volume.
Authorizing users to access cloud services is possible by creating user
identities in the cloud, but most organizations already have user identities on
their own authentication servers. Identity federation allows users

authenticated within an organization to get authorized to cloud services, all
without re-creating or replicating user accounts to the cloud.
Risks such as network latency, lack of cloud provider data
standardization, or a cloud provider going out of business must be
considered when evaluating cloud solutions.
Rapid application development and testing is possible with PaaS because
of how quickly virtual machines can be provisioned and because of prebuilt

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