The present system includes a system, method and device for inferring connectivity between network devices across a third party network. Configuration data related to the network devices is examined and configuration data about the network is inferred. The inferred configuration data may be related to a communication protocol, network bandwidth, and the like. A model representing the network is then created to indicate inferred interfaces and connections through the external network between network devices. The representation may be rendered in various forms, such as a display or data exported to another system. Various studies may also be performed using the model, such as traffic, routing, or planning studies.