Overview of a VNF

A VNF, or Virtual Network Function, provides a single function within a Network Service. A VNF consists of one or more VNFCs (Virtual Network Function Component).

An overview of a VNF is given as follows:
  • A Network Service (defined via an Assembly Descriptor) is made up of one or more VNFs
  • A VNF (also defined via an Assembly Descriptor) is made up of one or more VNFCs
  • A VNFC (defined via a Resource Descriptor) is made up of:
    • Lifecycle Ansible® scripts
    • One or more VDUs (Virtual Deployment Unit) - Each VDU will be tied to a specific infrastructure type.
Following are the components and their definitions:
VDU
A VDU is the package or script that can create an image for specific virtual infrastructure.
VNFC
This is the VNF component as a standalone network function that is managed by a Resource manager. In the orchestration component, this is also called a Resource.
  • VDU or multiple VDUs
  • Descriptor (Resource) is a yaml file that describes the interface for a VNFC. Contains properties and other details to describe the interface for the item.
  • Lifecycle scripts: Scripts that map the standard lifecycle actions as start, stop, install, configure, stop to the VDU specific instructions.
VNF
Provides a single function within a Network Service.
  • VNFC: A VNF can consist of multiple VNFCs
  • VNF Descriptor: An assembly.yaml file that describes the interface for a VNF. Contains properties and other details to describe the interface for the VNF. Implemented within the orchestration component by an assembly.
  • VNFC: One or more VNFCs
  • Service Behavior Test scenarios (if any)