Page 80 - Cloud Essentials

use XML to transmit information and allowing developers to export the web

service definition to a text file; these are standards that allow web services
to interact with dissimilar systems and also to be imported into other
environments. Here are some examples of relevant standards you should
look for:

Data formats These include eXtensible Markup Language (XML)
and JavaScript Object Notation (JSON).

Data storage Being able to move data from cloud to cloud reduces
lock-in to a storage provider. This might include the option to export
cloud data to a standard file format that can be imported to a different
cloud storage provider.

Standard virtual machine images This offers the ability to move a
virtual machine from one cloud to another.

Standard application programming interface (API) This allows for
provisioning web services in order to prevent vendor lock-in.

Identity information standards These include Open Authorization
(OAuth), OpenID, and Security Assertion Markup Language (SAML).

CERTIFICATION OBJECTIVE 3.03

Cloud Computing Risks and Challenges

Cloud technology eliminates some existing risks, such as lack of capacity or
slow deployment, but introduces new risks. The risks originate from
different technical characteristics in a networked environment, from the

potential openness of systems, and from the fact that resources are shared.

Application Performance
In a cloud environment, the most likely culprit that will affect application

performance is the network link separating cloud clients and cloud servers.
The performance and speed of network links are described by terms such as
bandwidth and latency.

Bandwidth and Latency
As mentioned earlier in this chapter, bandwidth defines how quickly data

can be moved over a wired or wireless connection. The amount of time it
takes for data to travel from one end of a network link to the other is called

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