Network Service Model and TOSCA Types

Owned by Nagesha Subramanya
Last updated: Mar 20, 2018
3 min read

Building NS modular bring a lot of benefits.

  • Simplifies NS building ; simple small networks built and then composed to make it complex.

  • Reduces maintenance overheads.

  • Allows reuse ; use the existing the network service.

  • Individual NS can be from different companies.

  • Can have hierarchy.



The proposal is to define the TOSCA node model for the NS  (abstract and substituted service template) which facilitates the modularity , composition and nesting of NS. 

  • NS can include VNF, PNF and other nested NS along with the SAP if any.







  • Nested NS is represented as an abstract node which can have its implementation as another service template or it can be referenced from an existing NS.


Network Service node (abstract)
node_types: tosca.nodes.nfv.NS.NS1: derived_from: tosca.nodes.Root version: 1.0.0 description: specific network service node. properties: id: type: string description: network service descriptor identifier (NSD). required: true designer: type: string description: identifies the designer of NSD. required: true version: type: string description: identifies the version of NSD. required: true name: type: string description: name of the NSD. required: true invariantId: type: string description: version independent network service descriptor identifier (NSD). required: true ... interfaces: Basic: type: tosca.interfaces.nfv.ns.lifecycle.Basic ... requirements: - virtualLinkable1: tosca.capabilities.nfv.VirtualLinkable - virtualLinkable2: tosca.capabilities.nfv.VirtualLinkable
Network Service template
description: World Famous Network Service topology_template: substitution_mappings: node_type: tosca.nodes.nfv.NS.NS1 properties: id: 316aa140-c99a-4a08-b8f5-8e2cb73c83e8 designer: Nokia version: "1.0.0" name: "World Famous" invariantId: 416aa140-c99a-4a08-b8f5-8e2cb73c8fef requirements: - virtualLinkable1: [ vnf1, virtualLinkable2 ] - virtualLinkable2: [ SAP1, virtualLinkable2 ] capabilities: ... interfaces: ... node_templates: vnf1: type: tosca.nodes.nfv.VNF.VNF1 properties: ... requirements: - virtualLinkable1: VL1 #virtualLinkable2 is exposed through substitution mapping ns2: type: tosca.nodes.nfv.NS.NS2 properties: ... requirements: - virtualLinkable1: VL1 pnf: type: tosca.nodes.nfv.PNF.PNF1 properties: ... requirements: - virtualLinkable1: VL1 VL1: type: tosca.nodes.nfv.VL properties: ... SAP1: type: tosca.nodes.nfv.SAP properties: layer_protocol: ipv4 sap_address_assignment: true requirements: - virtualLinkable1: VL1 #virtualLinkable2 is exposed through substitution mapping ...