The article says: "For quite some time we've been grilling our candidates about dirty corners of TCP/IP stack. Every engineer here must prove his/her comprehen

The article says: "For quite some time we've been grilling our candidates about dirty corners of TCP/IP stack. Every engineer here must prove his/her comprehensive understanding of the full network stack. For example: what are the differences in checksumming algorithms between IPv4 and IPv6 stacks? I'm joking of course, but in the spirit of the old TCP/IP pub game I want to share some of the amusing TCP/IP quirks I've bumped into over the last few months while working on CloudFlare's automatic attack mitigation systems." That is, these are not real interview questions. They are trivia questions. I doubt most engineers even at Cloudflare can answer these without research.