Release 0 Data Model Details
Overview
OSM supports descriptors for Virtual Network Functions and Network Services. The data models for these descriptors are aligned with ETSI MANO [1].
Virtual Network Function Descriptor [VNFD] defines the VNF and resources required for realizing the network function. The descriptors includes various components that are part of the VNF. In addition, VNFD also defines the VNF level configuration information.
Network Service Descriptor [NSD] defines a set of interconnected VNFs to realize a network service spanning multiple VNFs. In addition, NSD also defines the NS level configuration information.
Network Service Descriptor
The NSD connects VNFs using the Virtual Links (VLs) as shown in the following diagram:
The VNFs attach to the VLs using the Connection Points (CPs). So the NSD captures the list VNFs and the VLs that connect the VNFs. The following diagram illustrates the high level objects in an NSD:
An example NS containing an IMS VNF is here.
Virtual Network Function Descriptor (VNFD)
The VNFD connects Virtual Deployment Units (VDUs) using the internal Virtual Links (VLs). Each VDU represents a VM/Container. The following diagram illustrates the internal structure of VNFD:
The VDUs attach to the internal VLs using the internal Connection Points (CPs). So the VNFD captures the list VDUs and the internal VLs that connect the VDUs. Note that for a VNF containing a single VDU, there may not be any internal VLs. The following diagram illustrates the high level objects in an VNFD:
An example IMS VNF is here.
Data Modeling Language and Format
The VNF and NS descriptors are modeled using YANG. The input format for descriptor is YAML. The descriptors are validated against the YANG schema when the VNF/NS packages are on-boarded. For details about the YANG schema and descriptors refer to the "Detailed Documents/Information" section below.
Packages
The NSD and VNFD are on-boarded using NS and VNF packages respectively. At the time of instantiation additional artifacts such as images, icons, scripts, and charms are needed in addition to the descriptors. To provide a simple and one click on-boarding experience the packages encapsulate all necessary artifacts in addition to the descriptors. The packages are distributed in the tar.gz format.
NS Package
The NS package may contain the following files and directories:
| - nsd.yaml
| - README
| - checksum.txt
| - scripts\
| - icons\
| - config\
VNF Package
The VNF package may contain the following files and directories:
| - vnfd.yaml
| - README
| - checksum.txt
| - imagess\
| - scripts\
| - icons\
| - charms\
Detailed Documents/Information
Data Model Document: Media:OSM_Release0_Data_Models.doc
UML representation of Network Service Descriptor: Media:Nsd.png
UML representation of VNF Descriptor Media:Vnfd.png