Class Diagram
Based on ONF Core IM, ONAP R2+ Wan Descriptor IM is designed as below class diagram:
The Wan Descriptor is made of some service components and resources. The resources are painted in yellow in the class diagram.
- Forwarding Construct: The Forwarding Construct (FC) class models enabled constrained potential for forwarding between interfaces at a particular specific layerProtocol.
- FC Point: Fowarding Construct Point. The association of the FC to interfaces is made via FC Points. The FC Point class models the access to the FC function.
- Node: Node resource, it could be a site or a network element or anything else which can be a host for endPoint or any other node.
- FC Route: The routing relationships within FC are described, including routing between sub FC (interdomain links), and links between network elements, and exchange relationship within network elements. SubFc describes the lower level FC. FC objects support a recursive aggregation relationship such that the internal construction of FC can be exposed as multiple lower level FC objects (partitioning). Lower level FC could belong to different domain, which is useful for cross domain FC.
- Link Connection: The exchange relationship between nodes, describing how the interfaces between nodes are linked. The link can depend on the FC of the service layer, such as overlay network depend on underlay network.
- XC: Exchange Connection. The exchange relationship within a node describes how the interfaces within the node are linked.
- XC Point: Exchange Connection Point. Interfaces involved in exchange in a node or a link.
The wan descriptor application for general scenario is shown as below diagram:
There is a special resource class not shown in the class diagram above, that is configuration. The classes of Wan Descriptor shown above are abstract, we could use them to describe any wan scenario with specify configuration which has the specify parameters for the scenario. For example, we could use overlay vpn configuration an FC to describe overlay vpn. All specify configuration classes are derived from configuration base class which is shown as below diagram:
The specify configuration class will be consumed by specify Direct Graph in SDN-C. As we could import configuration class in SDC and import DG in SDN-C dynamically, new wan scenario could be taught to ONAP after version release.
Use Case Example
Take the ONAP R1 VoLTE use case as an example. Volte wan contains overlay vpn and underlay vpn, both of them could be described as a FC. And the relationship between overlay vpn and underlay vpn could be described by FCRoute and LinkConnection.
The class diagram of ONAP R1 VoLTE use case shown as below:
Wan descriptor node type definition example: WAN_type_definition.yaml
Volte Wan configuration node type definition example: WAN_Volte_wan_configuration_definition.yaml
Volte Wan template example: VoLTE_WAN_template.yaml