RFC 1468 (rfc1468) - Page 1 of 6
Japanese Character Encoding for Internet Messages
Alternative Format: Original Text Document
Network Working Group J. Murai
Request for Comments: 1468 Keio University
M. Crispin
Panda Programming
E. van der Poel
June 1993
Japanese Character Encoding for Internet Messages
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard. Distribution of this memo is
unlimited.
Introduction
This document describes the encoding used in electronic mail [RFC 822]
and network news [RFC 1036] messages in several Japanese networks. It
was first specified by and used in JUNET [JUNET]. The encoding is now
also widely used in Japanese IP communities.
The name given to this encoding is "ISO-2022-JP", which is intended
to be used in the "charset" parameter field of MIME headers (see
[MIME1] and [MIME2]).
Description
The text starts in ASCII [ASCII], and switches to Japanese characters
through an escape sequence. For example, the escape sequence ESC $ B
(three bytes, hexadecimal values: 1B 24 42) indicates that the bytes
following this escape sequence are Japanese characters, which are
encoded in two bytes each. To switch back to ASCII, the escape
sequence ESC ( B is used.
The following table gives the escape sequences and the character sets
used in ISO-2022-JP messages. The ISOREG number is the registration
number in ISO's registry [ISOREG].
Esc Seq Character Set ISOREG
ESC ( B ASCII 6
ESC ( J JIS X 0201-1976 ("Roman" set) 14
ESC $ @ JIS X 0208-1978 42
ESC $ B JIS X 0208-1983 87
Note that JIS X 0208 was called JIS C 6226 until the name was changed
Murai, Crispin & van der Poel