1. A method comprising: mapping entities of a first network model to a second network model, identifying added, removed, and matched entities based on the mapping, comparing the matched entities to identify modified entities having one or more configuration differences, and reporting configuration differences between the first and second network models based on the added, removed, and modified entities, wherein 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, and each refinement is based on a set of rules associated with the corresponding network entity.