Valid domain names must have a minimum length of 3 and up to 63 alphanumeric characters (.lu excluded) per name (a . . . z, 0 . . . 9,-).
A domain name may contain letters or figures (a..z, 0...9). Only the hyphen.
(-) is allowed as special character. The hyphen can only be used in between two characters and not as first or last character of a domain name. Use only lower case characters as domain names are case insensitive.
