Page 560 - Cloud computing: From paradigm to operation

3 XaaS

5 Convention

The keywords "is required to" indicate a requirement which must be strictly followed and from which no
deviation is permitted if conformance to this Recommendation is to be claimed.
The keywords "is recommended" indicate a requirement which is recommended but which is not absolutely
required. Thus this requirement need not be present to claim conformance.
The keywords "can optionally" indicate an optional requirement which is permissible, without implying any
sense of being recommended. This term is not intended to imply that the vendor's implementation must
provide the option and the feature can be optionally enabled by the network operator/service provider.
Rather, it means the vendor may optionally provide the feature and still claim conformance with the
specification.
In the body of this Recommendation and its annexes, the words shall, shall not, should, and may sometimes
appear, in which case they are to be interpreted, respectively, as is required to, is prohibited from, is
recommended, and can optionally. The appearance of such phrases or keywords in an appendix or in material
explicitly marked as informative are to be interpreted as having no normative intent.

6 Introduction to desktop as a service (DaaS)
DaaS is defined as a cloud service category in which the capabilities provided to the cloud service customer
(CSC) are the ability to build, configure, manage, store, execute and deliver users' desktop functions remotely.
With DaaS, the user experience is achieved through a user interface, which is presented on a DaaS client over
the network. Figure 6-1 shows the conceptual view of DaaS.

Figure 6-1 – Conceptual view of DaaS

Instead of maintaining and running a desktop operating system and applications on CSC devices, servers of a
cloud service provider (CSP) located in the cloud are used to execute the instances of users' virtual desktops.
This allows a party (e.g., an organization) to run end user's operating systems and applications, and keep
their data in the cloud computing environment.

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