Domain names may (when this is written, February 2001) not contain other characters than A-Z, a-z, 0-9, " -" and "." between elements. Upper and lower case characters are indifferent to the meaning of a domain name. Many people want to use national characters in other languages than English, like "é" and "ä", in domain names. Various proposals for modifying the DNS to allow this are being discussed. One group of proposals is using a method which does not require any changes at all in the way the domain name servers work. How can this be achieved?


Encode the forbidden characters using some encoding rule, which encodes them into the set of permitted characters. The encoding rule can for example be similar to the BASE64 or QUOTED-PRINTABLE encodings in MIME. However, since upper and lower case characters in domain names are identical, BASE32 should be used instead of BASE64. BASE32 is an encoding which only uses lower case characters.

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