OS Multi-modal Routing Network (OS MRN) is designed and built in the OpenSteetMap (OSM) schema to facilitate straightforward import into many routing software applications. The OpenStreetMap model has three core data elements: ways, nodes and relations. See Elements - OpenStreetMap Wiki for more information.
A way represents a linear feature on the ground. In OS MRN, these are called Transport Links and are linear representations of where people can travel along a network.
A node is a single point in space. In OS MRN, these are called Transport Nodes and build up the topology of the network, connecting ways together.
A relation defines how other elements work together. In OS MRN, these are called Turn Restrictions and represent information about turn restrictions.
OSM uses a system of tags to apply information against different features. We have taken existing OS network and routing data and mapped this to the OSM schema. We will include all the values from the OSM schema in the OS MRN code lists, but not all values are populated in the first release of OS MRN.
Transport Links combine the following existing transport information into one feature type:
OS NGD Road Links
OS NGD Path and Connecting Links
OS NGD Ferry Links
OS NGD Railway Links
OS NGD Access Restrictions
OS NGD Speed data
Transport Nodes combine the following existing transport information and into one feature type:
OS NGD Road Nodes
OS NGD Path and Connecting Nodes
OS NGD Ferry Nodes
OS NGD Railway Nodes
Turn Restrictions take the existing OS NGD Turn Restrictions.