The General Modeling Network Specification (GMNS) defines data format specifications for modeling networks that work across software platforms and regions. GMNS facilitates seamless integration of tools and ideas in travel modeling, as well as tools and ideas developed in adjacent fields. It provides a uniform format for sharing routable road network files that is both human- and machine-readable.
GMNS (through version v0.96) was developed under the auspices of the Zephyr Foundation, with support from the Federal Highway Administration (FHWA), and is intended to facilitate the sharing of tools and data sources by modelers. It is designed to be used in multi-resolution and multi-modal static and dynamic transportation planning and operations models with time-varying networks.
From 2018 to 2024, the original GMNS Project Management Committee defined GMNS requirements, evaluated existing solutions, and drafted, disseminated, and revised the GMNS specification, which can be found here.
An introduction to GMNS can be found here: General Modeling Network Specification: A Specification for Sharing Routable Road Networks
Community members and researchers have developed an ecosystem of tools to facilitate use of GMNS, including:
A suite of tools for defining, creating, and building network scenarios — starting from a base network and layering project cards (network diffs) to create future networks and variants.
An open-source Python package for obtaining and converting OpenStreetMap networks — drivable, bikeable, walkable, railway, and aeroway — into GMNS-formatted files with a single line of code.
An open-source, cross-platform Python path engine for GMNS networks, offering fast shortest-path routing plus a framework for column-based (path-based) modeling and demand applications.
A small, multimodal demonstration network can be found here.
In 2024, a new, expanded Project Management Committee (PMC) formed, succeeding the original GMNS-only committee, to bring GMNS and NetworkWrangler together under shared governance.
To learn more about this project, please reach out to the google group, gmns@.
Lead: Lisa Zorn
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