pynem

Pynem is an open-source Python library for network emulation and experimentation. It provides a high-level API to define virtual topologies, configure interconnects, and run applications within an isolated emulated network. The library aims to make network experiments reproducible and accessible by offering Python-native configuration, modular components, and pluggable backends.

Core concepts include topologies, nodes (hosts and routers), links with adjustable parameters (bandwidth, delay, jitter, and packet loss), and an orchestration layer that launches processes and collects metrics. Pynem leverages Linux facilities such as network namespaces and traffic control to realize the emulated links and supports integration with common Python testing and data-analysis workflows.

Typical workflows involve constructing a topology in Python code, starting the emulation, launching client and server applications, performing measurements (throughput, latency, loss), and tearing down the environment. The library emphasizes simplicity and extensibility, enabling researchers and educators to prototype network scenarios quickly.

Relation to other tools: Pynem is positioned as a lighter-weight alternative to more feature-rich platforms such as Mininet, focusing on Python-native configuration and ease of use. It is intended for education, research prototyping, and automated testing.

Development and licensing: The project is maintained by an open-source community, with a public repository and contribution guidelines. Documentation covers installation, API reference, and examples.

See also: Mininet, network emulation, software-defined networking.