OMNeTs

OMNeTs is a general-purpose, open-source discrete-event simulation framework used primarily for modeling computer networks and other distributed systems. It provides a modular, component-based environment in which researchers can build complex models from reusable pieces and study system behavior under varied conditions. The core simulator manages event scheduling, execution order, and data collection while remaining flexible enough to support different modeling goals.

Models in OMNeTs are described using the Network Description (NED) language to declare modules and their connections, and implemented in C++. Simple modules encapsulate behavior, while compound modules group submodules into hierarchical structures. This separation of description, implementation, and composition enables reuse and scalable design of large networks. The framework supports custom statistics, logging, and scenario configuration to support repeatable experiments.

OMNeTs includes visualization and debugging tools, notably Tkenv and Qtenv, which allow stepping through events, inspecting module state, and animating network activity. It also supports parallel and distributed simulation to handle large-scale experiments across multiple processors. A rich ecosystem of models and libraries exists, with INET providing comprehensive protocols and components for IP networks, wireless links, mobility, and related technologies.

Applications of OMNeTs span wired, wireless, and mixed-network research, including wireless sensor networks, vehicular networks, Internet of Things, and protocol evaluation. It is widely used in academic settings for teaching and research as well as in industry for rapid prototyping of network concepts.

The project is open-source and available under an academic license that permits free use for research and education.