Page 676 - Cloud computing: From paradigm to operation

3 XaaS

QoS Quality of Service

SDN Software-Defined Networking
SLA Service Level Agreement

vCDN Virtual Content Delivery Network
vEPC Virtual Evolved Packet Core

vIMS Virtual IP Multimedia Subsystem
VM Virtual Machine
VNF Virtualized Network Function

VPC Virtual Private Cloud
VPN Virtual Private Network

VPNaaS VPN as a Service
vRouter Virtual Router
vSwitch Virtual Switch

VXLAN Virtual Extensible Local Area Network
WAN Wide Area Network

5 Conventions

None.

6 Overview of NaaS functional architecture

6.1 Key NaaS characteristics
The NaaS functional architecture aims for a scalable and programmable on-demand network allowing the
cloud service customer (CSC) to provision network services (NSs) and resources, as needed, automatically or
with minimal interaction with the NaaS cloud service provider (CSP). Key NaaS characteristics to be achieved
include:
– Self-service: the ability to manage network services automatically or with minimal human
interaction. Examples include self-provisioning, self-care and self-design;
– On-demand: the ability to deploy and adjust (increase or decrease) network services rapidly and as
needed. Examples include fast time-to-market, try before you buy, accelerate innovation, easy
migration, update and upgrade;
– Scalability: the ability to scale network services and resources (scale out, in, up or down) in response
to a large usage demand. Example includes scale-up resources based on traffic growth;
– Programmability: the ability to access services features through application programming interfaces
(APIs). Examples include programmable quality of service (QoS) and network policy rules;

– Measured service: metered delivery of services such that usage can be monitored, controlled,
reported, and charged. Example includes case of NaaS CSCs charged only for the services or
resources that they use.

668