The BBC's Geostats prototype (2010) detects censorship events by normalizing hourly traffic from two sources — a web-bug-based Livestats API and approximately 30GB/day of uncompressed Akamai streaming logs — alerting when traffic deviates ±60% from a rolling historical average keyed to hour-of-day and day-of-week. A key limitation identified is that CDN log files arrive up to 24 hours behind real-time, preventing timely detection of live blocking events.
From 2011-kathuria-bypassing — Bypassing Internet Censorship for News Broadcasters
· §2.2–§2.3
· 2011
· Free and Open Communications on the Internet
Implications
Operators building blocking-detection systems should combine near-real-time client-side telemetry (web beacons, app heartbeats) with server-side CDN logs to compensate for CDN log latency of up to 24 hours.
A ±60% threshold against a rolling same-hour/same-weekday baseline is a workable starting point for anomaly alerting, but should be supplemented with ISP-level granularity to distinguish blocking from network outage.