How Verizon and a BGP Optimizer Knocked Large Parts of the Internet Offline Today

Tom Strickx on Cloudflare’s blog:

Today at 10:30UTC, the Internet had a small heart attack. A small company in Northern Pennsylvania became a preferred path of many Internet routes through Verizon (AS701), a major Internet transit provider. This was the equivalent of Waze routing an entire freeway down a neighborhood street — resulting in many websites on Cloudflare, and many other providers, to be unavailable from large parts of the Internet. This should never have happened because Verizon should never have forwarded those routes to the rest of the Internet. To understand why, read on.

There have been smaller and larger outages over the past few years, with AWS failures triggering the biggest problems for users. These lasted for mere hours at worst and I’m sure darker scenarios is still to come. What will the fallout of a serious (week- or month-long) internet outage entail?