Definition of terms

Different standards developing organizations and communities use different terminology related to Network Function Virtualization, Cloud Computing, and Software Defined Networking. This list defines the terminology in the contexts of this document.

API
Application Programming Interface.
Cloud Computing
A model that enables access to a shared pool of configurable computing resources, such as networks, servers, storage, applications, and services, that can be rapidly provisioned and released with minimal management effort or service provider interaction.
Edge Computing
Edge computing pushes applications, data and computing power (services) away from centralized points to the logical extremes of a network.
Instance
Refers in OpenStack terminology to a running VM, or a VM in a known state such as suspended, that can be used like a hardware server.
NFV
Network Function Virtualization.
NFVI
Network Function Virtualization Infrastructure. Totality of all hardware and software components which build up the environment in which VNFs are deployed.
SDN
Software-Defined Networking. Emerging architecture that decouples the network control and forwarding functions, enabling the network control to become directly programmable and the underlying infrastructure to be abstracted for applications and network services.
Server
Computer that provides explicit services to the client software running on that system, often managing a variety of computer operations. In OpenStack terminology, a server is a VM instance.
vForwarder
vForwarder is used as generic and vendor neutral term for a software packet forwarder. Concrete examples includes OpenContrail vRouter, OpenvSwitch, Cisco VTF.
VIM
Virtualized Infrastructure Manager. Functional block that is responsible for controlling and managing the NFVI compute, storage and network resources, usually within one operator’s Infrastructure Domain, e.g. NFVI Point of Presence (NFVI-PoP).
Virtual network
Virtual network routes information among the network interfaces of VM instances and physical network interfaces, providing the necessary connectivity.
VM
Virtual Machine. Virtualized computation environment that behaves like a physical computer/server by modeling the computing architecture of a real or hypothetical computer.
VNF
Virtualized Network Function. Implementation of an Network Function that can be deployed on a Network Function Virtualization Infrastructure (NFVI).
WAN
Wide Area Network.