Where does “6in4” come from?

6in4 (English) comes from English in, from Middle English in, from Old English in, from Proto-West Germanic *in.

6in4 (English): An Internet transition mechanism for migrating from Internet Protocol version 4 (IPv4) to IPv6

Definitions

  1. An Internet transition mechanism for migrating from Internet Protocol version 4 (IPv4) to IPv6

Ancestry of “6in4”, step by step

6in4 traces back through 3 separate lines of ancestry.

via English in

StepLanguageWordMeaning
1EnglishinUsed to indicate location, inclusion, or position...
2Middle EnglishinAny kind of accomodation; particularly; A home or...
3Old Englishinin; Alternative form of inn
4Proto-West Germanic*in

via English 4

StepLanguageWordMeaning
1English4abbreviation of for

via English 6

StepLanguageWordMeaning
1English6MI6; the agency or a particular agent
Every word from Proto-West Germanic *inEvery word from Old English inEvery word from Middle English in