Korean Character Encoding for Internet Messages (RFC1557)
Original Publication Date: 1993-Dec-01
Included in the Prior Art Database: 2000-Sep-12
Internet Society Requests For Comment (RFCs)
U. Choi: AUTHOR [+3]
This document describes the encoding method being used to represent Korean characters in both header and body part of the Internet mail messages [RFC822]. This encoding method was specified in 1991, and has since then been used. It has now widely being used in Korean IP networks.
Network Working Group U. Choi
Request for Comments: 1557 K. Chon
Category: Informational KAIST
Solvit Chosun Media
Korean Character Encoding for Internet Messages
Status of this Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
This document describes the encoding method being used to represent
Korean characters in both header and body part of the Internet mail
messages [RFC822]. This encoding method was specified in 1991, and
has since then been used. It has now widely being used in Korean IP
This document also describes the name of the encoding method which is
to be used in order to match the message header and body format of
MIME [MIME1, MIME2].
This document describes only the encoding method for plain text.
Other text subtypes, rich text and similar forms of text, are beyond
the scope of this document.
It is assumed that the starting code of the message is ASCII. ASCII
and Korean characters can be distinguished by use of the shift
function. For example, the code SO will alert us that the upcoming
bytes will be a Korean character as defined in KSC 5601. To return
to ASCII the SI code is used.
Therefore, the escape sequence, shift function and character set used
in a message are as follows:
SO KSC 5601
ESC $ ) C Appears once in the beginning of a line
before any appearance of SO characters.
The KSC 5601 [KSC5601] character set that includes Hangul, Hanja
(Chinese ideographic characters), graphic and foreign characters,
etc., is two bytes long for each character.
For more information about Korean character sets please refer to the
KSC 5601-1987 document. Also, for more detailed information about
the escape sequence and the shift function you can look for the ISO
2022 [ISO2022] document.
Where this document in its formal syntax does not agree with the
description part, priority should be given to the formal syntax of
The notations used in this section of the document are according to
those used in STD 11, RFC 822 [RFC822] with the same meaning.
* (asterisk) has the following meaning :
The above means that "anything" has to be used at least l times and
at most m times. Default values for l and m are 0 and infinitive,
body = *e-line *1( designator *( e-line / h-line ))
designator = ESC "$" ")" "C"
e-line = *te...