Collos is a platform provided by Semtech which provides localization algorithms as a service. Please refer to http://preview.collos.org/ for more information and for signing up.
ChirpStack Geolocation Server integrates with the Collos v2 TDoA localization algorithm. Both single-frame and multi-frame TDOA are implemented.
For more information on metrics, see Prometheus metrics. The Collos backend exposes the following metrics:
A Histogram type metrics tracking the total number of API calls to the Collos API endpoint and their durations (using buckets).