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

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.

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Hasnain says:

Interesting read on the internet outage yesterday - full of technical details and a really accessible explanation of what happened. It also contains good explanations for preventative measures ISPs can take.

Also full of Cloudflare throwing *lots* of shade on Verizon. I'm impressed that this came out in ~8 hours, that legal signed off, and that Verizon haven't pushed back yet.

"IRR filtering would not have increased Verizon's costs or limited their service in any way. Again, the only explanation we can conceive of why it wasn't in place is sloppiness or laziness."

"All of the above suggestions are nicely condensed into MANRS (Mutually Agreed Norms for Routing Security)"

Posted on 2019-06-25T15:59:52+0000