Page 710 - Cloud computing: From paradigm to operation

3 XaaS

Appendix III

Relationship between NaaS functional architecture and SDN
(This appendix does not form an integral part of this Recommendation.)

As categorized by [ITU-T Y.3512], NaaS services are divided into NaaS application services, NaaS platform
services, and NaaS connectivity services. As a kind of cloud service, based on its use cases and derived
functional requirements specified in [ITU-T Y.3512], network connectivity service can be implemented by the
traditional technologies and/or emerging technologies, such as SDN.
Both cloud computing and SDN have their own reference architectures, whose mapping is presented in Figure
III.1. NaaS connectivity is a kind of cloud service, which is located in the services layer of the cloud reference
architecture. If it is supported and implemented by SDN, a NaaS connectivity service can be regarded as one
kind of SDN application in SDN architecture and seen as a bridge between the cloud computing and SDN
architectures.

Figure III.1 – Mapping of architectures of cloud computing and SDN

Figure III.2 presents the positioning of a NaaS connectivity service as an application in the SDN architecture.
Such NaaS connectivity service interacts with SDN management functionalities and SDN control layer
functionalities including application support entity, orchestration entity, abstraction entity.

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