That would be IP over some lower level physical layer, not some custom content stuffed into an IP packet :) (It's absolutely worth reading some of those old Ap

That would be IP over some lower level physical layer, not some custom content stuffed into an IP packet :) (It's absolutely worth reading some of those old April Fools' RFCs, by the way [0]. I'm a big fan of RFC 7168, which introduced HTTP response code 418 "I'm a teapot".) [0]: https://en.wikipedia.org/wiki/April_Fools%27_Day_Request_for_Comments#List_of_April_Fools'_Day_RFCs https://en.wikipedia.org/wiki/April_Fools%27_Day_Request_for...