Page 633 - Cloud computing: From paradigm to operation

XaaS 3

II.2.2 Detailed use cases

II.2.2.1 NaaS platform use case for cloud CDN

Title NaaS platform use case for cloud content delivery network (CDN)
Description Content provider acting as CSC stores the content in the data centre and monitors the
usage of the content. When the usage of the content reaches certain level of popularity or
if according to some predictions content provider expects a growth of popularity in a
defined period of time, e.g., video transmission of a sport event, content provider creates a
virtual CDN to temporarily move the content from the data centre to the network (vCDN).
XaaS CSP receives the content from the content provider (which can itself create a
distribution service). Content is delivered to the cloud service users (CSUs) from XaaS CSP
data centre using the network of NaaS CSP. The XaaS CSP offers the possibilities to store
the content and to monitor usage parameters. XaaS CSP in cooperation with the NaaS CSP
can duplicate the content in the network nodes, building a virtual CDN service. Basically
XaaS CSP supports CDN functions, thus CDN is in some way "emulated" by the XaaS CSP,
which cooperates with the NaaS CSP.
Roles CSU, CSC, CSP

Figure
(optional)

Pre-conditions – Content provider acting as CSC stores the content in XaaS CSP data centres.
(optional) – Content provider acting as CSC monitors the use of content.
Post-conditions – XaaS CSP offers the virtual CDN service using network resources of the NaaS CSP.
(optional) – Content provider acting as CSC decides to move content from the data centre to the
virtual CDN for a defined period of time.
Derived – Performance (refer to clause 7.1)
requirements – Operation and management (refer to clause 7.2)
– Service chain (refer to clause 7.3)

II.3 NaaS platform related use cases

II.3.1 General use cases
None.

II.3.2 Detailed use cases

II.3.2.1 NaaS platform use case for service chain

Title NaaS platform use case for service chain
Description With CSC's tenants increasing requirements on the service diversity and complexity, CSP
needs to deliver integrated network application services, such as deep packet inspection
(DPI), intrusion detection, intrusion prevention, load balance, firewall, etc. Traditionally,
the set of services are provided using dedicated physical network elements, which have
limited network capacity and functionalities, complex configuration and update, and
lengthy provision period. The situation, when the output of one service is used as input for
the other service is called service chain. In traditional network the set-up of services chain,

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