The open-source On-Chip Communication Network (OCCN) defines an efficient framework for network-on-chip modeling and simulation based on an object-oriented C++ library built on top of SystemC. OCCN increases the productivity of developing communication driver models through the definition of a universal communication API. This API provides a new design pattern that enables creation and reuse of executable transaction level models (TLMs). OCCN also addresses protocol refinement, design exploration, and high-level performance modeling.