In developing the TMF920A Topology Discovery Service and the supporting TMF686 API Topology graph API it was realized that the Information Model Framework needed to separate the specification of Graphs, Vertices and Edges from instances of Graphs, Vertices and Edges. For example there may be multiple Vertex Specification for different types of Router (ProviderEdge, Core,etc.), Router shelves ( self powered unpowered) Router Slide in Card(Wired Gigabit Ethernet, Optical), Power Supplies, Power Distribution Bars, communication links, etc.; that each require their own specification of parameters that need to be modeled and instantiated in instances of vertices and edges. Instance normally comply to one specification type. <br/>
