1. A method of inferring connectivity between unconnected network segments, the method comprising: identifying, by a network analysis system, network segments that, based on available configuration data, are unconnected; examining, by the network analysis system, the configuration data related to the unconnected network segments; creating, by the network analysis system, an abstraction of at least one external network that is assumed to connect the unconnected network segments, the abstraction including two or more newly created interfaces and including one or more connections between these interfaces that are not directly identified in the configuration data; inferring, by the network analysis system, routing protocol configuration data for each of the interfaces based on protocol information in the examined configuration data; and rendering, by the network analysis system, the abstraction of the at least one external network.