Discussion on Chinese Domain Name technology including encoding, testing
Clean 8 bits & UTF-8 problem Escape code “ \ ” rule must be clear. Ex. 成功成功 \ Other special character in UNIX shell Ex. 教育 (|) “ 教育 ” will be workable
Windows 9X Ex. 統一企業 will be error Automatic insertion “ \ ” in DNS, not insertion “ \ ” in DHCP Ex. ping 成功 \ 大學 Windows 2K UTF-8 in resolver(ping,ftp) Clean 8 bits in nslookup Double encoding in IE5 and resolver Clean 8 bits & UTF-8 problem
Windows Client & Server 之轉碼
Suggestion Chinese character & Alpha numeric character mixed sub-domain name. if there exist 8 bits character then that sub-domain character is case sensitive
For example: 王.tw 王.TWthe same For example: 王.tw 王.twdifferent Suggestion
Multi-lingual Multi-Byte character & single byte character 的問題 多國語言使用 multi-byte character
Problem (1) Multi-byte character has the byte code that is equivalent to single byte ASCII code, and some intermediate processing software package(Ex. BIND, sendmail, web proxy) can not recognize them separately. Especially in control character code ( “ \ ”, ”, ” | ”… )
Solutions Solution 1 Multi-byte character: \nnn\nnn. Solution 2 Non ASCII code transformation. UTF-8 Solution 3 All character transform to pure ASCII code, UTF-7, UTF-5 Solution 4 Clear byte stuffing, Escape code rule “ \\ ”, ” ”
Problem (2) All alphanumeric domain name is case insensitive, Multi-byte character is case sensitive.
Solutions Solution 1 Alphanumeric character transfer to lower(or upper) case first. (client iDNS UTF5) Solution 2 All Multi-byte character are transformed to UTF-8, so the multi-byte character will 8th bit set (negative byte) and it will be recognized easily. (win 2K DNS server)
Solutions Solution 3 If there exists one multi-byte character in sub-domain name, than that sub-domain will be case sensitive. (BIND server) For ex. : 王.tw “ A 王 ” is case sensitive
Why need solution 3 Clear 8 bits is possible Leading byte encoding has been used popularly (BIG5, GB, JIS … ) Compression ratio and conversion efficiency ? An intermediate stage toward UNICODE.