Reachability Score Summary
The BGP Reachability Score metric is related to the Availability Score, and both are designed to gauge the availability of your monitored prefixes to Catchpoint's network of BGP collectors. The difference between these metrics is that Reachability Score disregards any peers which have not had a path to the prefix for over 24 hours. This eliminates the effect of regionality on the metric, as any peers in regions that the prefix is not advertised to will be ignored. The two metrics are calculated as follows:
Availability Score = (# Peers with path ) / (# All Peers) * 100
Reachability Score = (# Peers with path) / (# Peers that had path within previous 24 hours) * 100
Limitation
Please note that Reachability Scores are not available for data collected prior to the Allegro release. Charts for times prior to March 17, 2022 will indicate a Reachability Score of 0.