1. A method comprising: mapping, by a data processing machine, entities of a first network model to a second network model, the second network model having a different arrangement of entities than the first network model, and the mapping establishes a correspondence between corresponding entities in each model, identifying, by the machine, added, removed, and matched entities based on the mapping, comparing, by the machine, the matched entities to identify modified entities having one or more configuration differences, and reporting, by the machine, configuration differences between the first and second network models based on the added, removed, and modified entities, wherein: each of the first and second network models provides a high-fidelity representation of the actual network, and includes representations of physical devices and links between the devices, the mapping includes a sequence of refinements of objects in each of the first and second network models, the sequence of refinements correspond to mapping to different network entities, each refinement is based on a set of rules associated with the network entity corresponding to the refinement, the mapping at each refinement includes providing a label to each network object associated with the network entity, combining each label from each refinement of the sequence of refinements to identify each network object by a composite label, and identifying the matched entities in each of the first and second network models as those having the same composite label.
1. A method comprising: mapping, by a data processing machine, entities of a first network model to a second network model, the second network model having a different arrangement of entities than the first network model, and the mapping establishes a correspondence between corresponding entities in each model, identifying, by the machine, added, removed, and matched entities based on the mapping, comparing, by the machine, the matched entities to identify modified entities having one or more configuration differences, and reporting, by the machine, configuration differences between the first and second network models based on the added, removed, and modified entities, wherein: each of the first and second network models provides a high-fidelity representation of the actual network, and includes representations of physical devices and links between the devices, the mapping includes a sequence of refinements of objects in each of the first and second network models, the sequence of refinements correspond to mapping to different network entities, each refinement is based on a set of rules associated with the network entity corresponding to the refinement, the mapping at each refinement includes providing a label to each network object associated with the network entity, combining each label from each refinement of the sequence of refinements to identify each network object by a composite label, and identifying the matched entities in each of the first and second network models as those having the same composite label. 7. The method of claim 1 , wherein reporting the configuration differences includes providing an interactive user interface.