Each two-letter language code (of ISO 639-1) has an equivalent three-letter code (as of ISO 639-2, and -3)
Since WMF servers use a mix of ISO 639-1 and ISO 639-2/3 (and some made up) codes for the language subdomains of their servers, it would aid those wanting to automatically link to them from multilanguage environments, and those who cannot memorize "the other" set of abbreviations, if servers were reachable under arbitray codes. There are no conflicts.
This could be had in two ways:
- on the DNS level, the three-letter-code-domain could be made an alias of, or cname to, the two-letter-code-domain.
- on the http level, all requests reaching a server via the three-letter-code-domain could be redirected to the appropriate two-letter-code-domain, using the http "redirect permanently" response code.
Imho the latter is preferrable because it creates less net traffic and server load while at the same time allowing linksetters to use any code set.
I don't know how many of the these codes are affected: While ISO 639-2 codes generally overlap with ISO 639-3 code, there are few languages, where ISO 639-2 offers additional ones, which are not present, and not used, in ISO 639-3. Also these could and should be redirected to their ISO 639-1 equivalents.
http://www.loc.gov/standards/iso639-2/php/code_list.php
gives a mapping of both code sets to the 2-letter codes
Version: unspecified
Severity: enhancement