Punycode
Sign in to savePunycode is a representation of Unicode with the limited ASCII character subset used for Internet hostnames. Using Punycode, host names containing Unicode characters are transcoded to a subset of ASCII consisting of letters, digits, and hyphens, which is called the letter–digit–hyphen (LDH) subset. For example, the German München (English: Munich) is encoded as Mnchen-3ya.
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Article
10 sectionsContents
- Origin of the name
- Description
- Separation of ASCII characters
- Encoding the non-ASCII characters
- Variable-length number encoding
- ACE prefix for internationalized domain names
- Examples
- See also
- References
- External links
Punycode is a representation of Unicode with the limited ASCII character subset used for Internet hostnames. Using Punycode, host names containing Unicode characters are transcoded to a subset of ASCII consisting of letters, digits, and hyphens, which is called the letter–digit–hyphen (LDH) subset. For example, the German München (English: Munich) is encoded as Mnchen-3ya.
While the Domain Name System (DNS) technically supports arbitrary sequences of octets in domain name labels, the DNS standards recommend the use of the LDH subset of ASCII conventionally used for host names, and require that string comparisons between DNS domain names should be case-insensitive. The Punycode syntax is a method of encoding strings containing Unicode characters, such as internationalized domain names (IDNA), into the LDH subset of ASCII favored by DNS. It is specified in IETF Request for Comments 3492.