FINDING · EVALUATION
During the February 2012 Dodo-Telstra BGP route leak, AS1221 (Telstra) exhibited a 20-minute congestion phase in which γC and γ3 both dropped while η rose from approximately 3 to 5 seconds, followed by a complete outage during which zero darknet sources were observed from the AS. The congestion phase produced measurable packet loss before the full blackout, providing an early-warning window of roughly 20 minutes.
From 2013-benson-gaining — Gaining Insight into AS-level Outages through Analysis of Internet Background Radiation · §IV-A · 2013 · Traffic Monitoring and Analysis
Implications
- Early η elevation (>4 s) on a path to a proxy AS can serve as a predictive signal of imminent full blockage — circumvention clients should begin failover to alternate relays before the link goes completely dark.
- A two-phase signature (congestion precedes blackout) can be detected with passive retransmit monitoring, giving circumvention infrastructure time to redistribute user load across providers.
Tags
Extracted by claude-sonnet-4-6 — review before relying.