Page 558 - Cloud computing: From paradigm to operation

3 XaaS

1 Scope
This Recommendation provides use cases, general requirements and functional requirements for desktop as
a service (DaaS).

2 References
The following ITU-T Recommendations and other references contain provisions which, through reference in
this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated
were valid. All Recommendations and other references are subject to revision; users of this Recommendation
are therefore encouraged to investigate the possibility of applying the most recent edition of the
Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is
regularly published. The reference to a document within this Recommendation does not give it, as a stand-
alone document, the status of a Recommendation.

[ITU-T X.1601] Recommendation ITU-T X.1601 (2014), Security framework for cloud computing.
[ITU-T Y.3501] Recommendation ITU-T Y.3501 (2013), Cloud computing framework and high-level
requirements.
[ITU-T Y.3510] Recommendation ITU-T Y.3510 (2013), Cloud computing infrastructure requirements.

3 Definitions

3.1 Terms defined elsewhere

This Recommendation uses the following terms defined elsewhere:
3.1.1 cloud service customer [ITU-T Y.3501]: A person or organization that consumes delivered cloud
services within a contract with a cloud service provider.
3.1.2 cloud service provider [ITU-T Y.3501]: An organization that provides and maintains delivered cloud
services.
3.1.3 hypervisor [ITU-T Y.3510]: A type of system software that allows multiple operating systems to
share a single hardware host.
3.1.4 virtual machine [b-DMTF OVF]: The complete environment that supports the execution of guest
software.

3.2 Terms defined in this Recommendation

This Recommendation defines the following terms:
3.2.1 DaaS client: A physical device and associated software running on the device that collectively
enables a cloud service user to access desktop as a service (DaaS).
3.2.2 desktop as a service (DaaS): A cloud service category in which the capabilities provided to the cloud
service customer are the ability to build, configure, manage, store, execute and deliver users' desktop
functions remotely.
3.2.3 virtual desktop: An environment for accessing end user's desktop functions remotely.
NOTE – Examples of end user's desktop functions can include desktop interface functions for applications, data access
functions for multimedia data, and control functions for input/output (I/O) devices.
3.2.4 virtual desktop infrastructure (VDI): A desktop as a service (DaaS) solution enabling the hosting of
a desktop operating system within a virtual machine.
NOTE – In this Recommendation, VDI means that the virtual machine hosting the desktop operation system is running
in a cloud computing environment.

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