The work presents a modeling and analysis framework for heterogeneous industrial networks architectures which is based on a tight integration of a network simulator with embedded software, middleware and a real-time operating system. This framework is suitable for modeling and simulating the behavior of typical components involved in factory automation applications (e.g., PLCs, remote controllers, operational screens, etc.) when they are connected through heterogeneous industrial networks. Experiments show that the framework allows to take early architectural decisions by evaluating the expected system performance based on the available models.