Page 679 - Cloud computing: From paradigm to operation

XaaS 3

Other aspects to be managed by the NaaS CSP include physical (hardware) resources (compute, storage and
networking resources), resource abstraction and virtual resources. The main functions of resource
abstraction are:
– abstraction of physical resources allowing decoupling of NFs from underlying physical resources;
– allocation of virtual resources from physical resources;
– provision of virtual resources (virtual compute, virtual storage) for execution of NFs as well as
virtualized network connectivity resources for interconnecting NFs of a given NS or for
interconnecting multiple NSs.

7 Functionalities for NaaS

This clause aims to provide the functionalities which are derived from the functional requirements specified
in [ITU-T Y.3512]. The mapping between NaaS service functional requirements and the functionalities
described in this clause is presented in Appendix I.

7.1 NaaS business related functionalities
Business related functionalities in the NaaS architecture are mainly related to the interaction between the
NaaS CSC and NaaS CSP regarding NaaS products offered by the NaaS CSP. This includes NaaS CSP
functionalities related to the selection and purchasing of specific NaaS products from a product catalogue by
the NaaS CSC and all other business related aspects, such as billing. An instance of a NaaS product represents
the subscription to a NaaS product by a given NaaS CSC.
NaaS business related functionalities cover cloud customer management and cloud product management
functionalities supported by the NaaS CSP as per [ITU-T Y.3521] where the cloud customer is a NaaS CSC and
the cloud product is a NaaS product. These functionalities include NaaS CSP's functionalities concerned with
the lifecycle of NaaS products offered to and purchased by NaaS CSCs, i.e., functionalities related to NaaS
products' order management, performance management, usage statistics, as well as the management of
NaaS product instances delivered to NaaS CSCs. More details about lifecycle management of cloud products
and services can be found in [ITU-T Y.3522].

7.2 Functionalities for NaaS service instantiation

7.2.1 Description of NaaS service instantiation
These functionalities are responsible for the instantiation of a NaaS service following the receipt of a valid
NaaS product (and associated NaaS services) order request from a NaaS CSC (e.g., a request for a vCDN
service or VPNaaS service). NaaS service instantiation functionalities maps the validated NaaS CSC request to
specific NaaS service deployment policies. For the requested NaaS service instance, the NaaS service
functionalities requests to the NaaS service orchestration functionalities (see clause 7.3) to realise the
corresponding automatic configuration of required NaaS resources (including network services, network
functions and resources) in the different infrastructure domains of the NaaS CSP (e.g., in access transport
domain, core transport domain and virtualization infrastructure domain) in a programmable manner.

NaaS service instantiation results in the instantiation of NaaS functional components (i.e., NaaS service
capabilities and NaaS administration capabilities components) in the service layer [ITU-T Y.3502] of the NaaS
CSP. For example, in the case of a VPNaaS service being instantiated, dedicated VPNaaS capabilities functional
components will be instantiated in the service layer. These VPNaaS service and administration capabilities
provided by the service layer will allow the NaaS CSC to request for management and configuration changes
of a VPN instance to the NaaS CSP and also enable the NaaS CSC to request dynamic VPN network
reconfiguration.
7.2.2 Modelling for NaaS service instantiation

As part of NaaS service instantiation functionality, a global, coherent and abstract view and representation
of NaaS resources (including network resources, network services, network functions and network
operational policies) used during the lifetime of the NaaS service instance will be provided and presented to

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