With Great Power Comes Great Responsibility

Frederik Ramm

Playlists: 'sotm2021' videos starting here / audio

The mapping of access restrictions is often neglected, but access restrictions (and default assumptions about whether a path without any such information is usable or not) are important to make OSM safe to use.

OpenStreetMap has grown from a geeky niche project to a respectable data source powering a multitude of apps and web sites.

Our ethos is to “map reality”, and our approach is incremental – one person might trace something from aerial imagery, another person might add a street name from their own local knowledge, and a third person surveys and records a speed limit on a visit to the area.

Many paths, trails, and streets have access restrictions that may not be apparent from aerial imagery. These could range from oneway traffic rules to restrictions on certain types of vehicles, to “no dogs allowed”, or something could be entirely private, or in a military danger area.

End users of OpenStreetMap based services are often insufficiently informed about access restrictions, leading to a rising number of complaints from land owners or otherwise responsible individuals, and frequent requests to “immediately remove from OSM” a certain object. This can either be due to missing access restrictions in OSM, or due to existing access restrictions not being correctly interpreted by the platform using OSM data.

This talk intends to take stock of the current situation in OSM and major data-consuming apps, and make some recommendations aimed at both mappers and data consumers in order to reduce the risk of leading users down the wrong path.

The author is a member of OpenStreetMap’s Data Working Group which handles incoming complaints.


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