Internet Outage Trends Sean Donelan Equinix Inc NANOG

Internet Outage Trends Sean Donelan Equinix Inc NANOG 21 Atlanta, Georgia

What are the questions? Was there any difference between Internet disruptions in 1999 and after Y 2 K? u Is the trend changing? u What really causes problems on the Internet? u What are fiber carriers and excavators doing to defend against the backhoe threat? u

Methodology u Reviewed multiple sources – – NANOG archives Newspaper archives Web searches Personal archives Identified unique outages (dedup multiple reports about the same event) u Did not identify root cause or carrier at fault u “Significant” – I know it when I see it u

Year to Year comparison

Sample Events Sep 17 1999 – Rochelle Park CO flooded u Sep 30 1999 – backhoe cuts gas line and fiber shared by multiple providers in Ohio u Nov 23 1999 – DCS failure, power outages, multiple fiber cuts on east and west coasts u May 22 2000 – Corrupt AS path crashes routers u Sep 8 2000 – Alternate fiber cut while u

Summary u 119 significant disruptions in 1999 u 93 significant disruptions in 2000 u Compared to FCC Telco reporting – 170 outages reported for 7/1/986/30/99 – 172 outages reported for 7/1/996/30/00

What are Diggers doing? u Database of excavators who routinely fail to notify One-Call centers u Free cellular call #DIG u Dig Safely and Common Ground Alliance u Improved ticket parsing and dispatching u New locating technology

Drill. Check u Courtesy: AT&T

Dig Safely

Internet Statistics? Internet reliability publicly measured by end-to-end connections u Effects of congestion are included in Internet measurements (busy signals) u Some backbones report 100% availability u End-to-end reachability exceeds 97% u 60% of Internet problems are repaired in less than 30 minutes u

What causes problems? u Analysis of Internet “outages” – – – – Maintenance (16. 2%) Loss of power (16%) Fiber cuts (15. 3%) Hardware failure (9%) Routing error (6. 1%) Congestion (4. 6%) Malicious attack (1. 5%) Software bug (1. 3%) Courtesy: Internet Performance Measurement and Analysis Project University of Michigan

Original Concept u Paul Baran; On Distributed Communications: 1. Introduction to Distributed Communications Network (1964)

Questions? Sean Donelan Sdonelan@equinix. com Equinix Inc