As per Relevance of the word information, we have this rfc below:
Network Working Group HF.
Request for Comments: 1922 Tsinghua
Category: Informational DY.
Tsinghua
ZG.
TC.
WCH.
M.
U
March 1996
Chinese Character Encoding for Internet
Status of this
This memo provides information for the Internet community. It
not specify an Internet standard. Distribution of this memo
unlimited
This memo describes methods of transporting Chinese characters
Internet services which transport text, such as electronic
[RFC-822], network news [RFC-1036], telnet [RFC-854] and the
Wide Web [RFC-1866].
As the use of Internet covers more and more Chinese people in
world, the need has increased for the ability to send
containing Chinese characters on the Internet. The methods
in this document provide means of transporting existing
character sets as well as leaving space for future extension
This document describes two encodings, ISO-2022-CN
ISO-2022-CN-EXT. These are designed with interoperability in
and are encouraged in this document for current Chinese interchange
they are 7-bit, support both simplified and traditional
using both GB and CNS/Big5, and do not impose any unusual
requirements on ASCII characters
As important related issues, this document gives
descriptions of the two encodings CN-GB and CN-Big5, and a
description of ISO/IEC 10646 [ISO-10646]. CN-GB and CN-Big5
Zhu, et al Informational [Page 1]
RFC 1922 Chinese Character Encoding March 1996
currently used as the internal codes for Chinese documents
ISO-10646 is the universal multi-octet character set defined by ISO
we feel that in the future it may become the preferred technology
Chinese documents and electronic mail when it is widely available
1. 7-bit Chinese encodings: ISO-2022-CN and ISO-2022-CN-
1.1.
ISO-2022-CN is based on ISO 2022 [ISO-2022], similar to earlier
on ISO-2022-JP [RFC-1468] and ISO-2022-KR [RFC-1557] for the
and Korean languages respectively. It is 7-bit, and supports
simplified Chinese characters using GB 2312-80 [GB-2312]
traditional Chinese characters using the first two planes of
11643 [CNS-11643], as well as ASCII [ASCII] characters
ISO-2022-CN-EXT is a superset of ISO-2022-CN that
supports other GB character sets and planes of CNS 11643.
Since ISO-2022-CN and ISO-2022-CN-EXT are 7-bit encodings, they
not require the 8-bit SMTP extensions. ISO-2022-CN supports all
Chinese characters that appear in Big5 [BIG5].
1.2. ISO-2022-
The starting code of ISO-2022-CN is ASCII. ASCII and
characters are distinguished by designations (ESC sequences)
shift functions
Designations define the Chinese character sets used in the text
There are three kinds of designations: SOdesignation, SS2
and SS3designation
The SOdesignation is in the form ESC $ ) , where is the "
character" assigned to the character set by ISO (refer to the
registry [ISOREG] for more details). The SS2designation is in
form ESC $ * , and the SS3designation is in the form ESC $ + .
A designation overrides any previous designation for subsequent
in the text
There are four kinds of shifts: SI, SO, SS2 and SS3. Shift
specify how to interpret the subsequent bytes
The shift SI (one byte with hexadecimal value 0F) declares
subsequent bytes are interpreted in ASCII
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The shift SO (one byte with hexadecimal value 0E) declares
subsequent bytes are interpreted in the character set defined
SOdesignation
The shift SS2 (two bytes with hexadecimal values 1B 4E) declares
the subsequent TWO bytes are interpreted in the character set
by SS2designation, after which the previous interpretation (from
or SO) is restored
The shift SS3 (two bytes with hexadecimal values 1B 4F) declares
the subsequent TWO bytes are interpreted in the character set
by SS3designation, after which the previous interpretation (from
or SO) is restored
The escape sequences, shift functions and character sets used in
ISO-2022-CN text are as follows
Character sets Shift in
--------------------------------------------------------------------
ASCII
GB 2312, CNS 11643-plane-1
CNS 11643-plane-2 SS
ESC $ ) A Indicates the bytes following SO are
characters as defined in GB 2312-80,
another SOdesignation
ESC $ ) G Indicates the bytes following SO are as
in CNS 11643-plane-1, until
SOdesignation
ESC $ * H Indicates the two bytes immediately
SS2 is a Chinese character as defined in
11643-plane-2, until another SS2
If there are any GB or CNS characters on a line, a designation
the corresponding character set must be used so that each line
its own character set information and the text can be
correctly when scroll back in a window. Also, there must be a
to ASCII (SI) before the end of the line (i.e., before the CRLF).
other words, each line starts in ASCII, and ends in ASCII
Example: the hex
1b 24 29 41 0e 3d 3b 3b 3b 1b 24 29 47 47 28 5f 50 0
represents the Chinese word for "Interchange" (jiao huan) twice
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RFC 1922 Chinese Character Encoding March 1996
the first time in simplified form using GB-2312 (the 3d 3b 3b 3
sequence above), and the second time in traditional form
CNS-11643 (the 47 28 5f 50 sequence above). The sequence 1b 24 29
41 is the SOdesignation for GB-2312, the 0e is SO to switch
Chinese from ASCII, the 1b 24 29 47 is the SOdesignation
CNS-11643 plane 1, and finally the 0f is the SI to return to
at the end of the line
The name given to this character encoding is "ISO-2022-CN". This
is intended to be used as the "charset" parameter in MIME [MIME-1,
MIME-2] messages
Content-Type: text/plain; charset=iso-2022-
The ISO-2022-CN encoding is already in 7-bit form, so it is
necessary to use a Content-Transfer-Encoding header
Other restrictions are given in the "Formal Syntax of ISO-2022-CN
(Section 7.1 of this document).
1.3. ISO-2022-CN-
ISO-2022-CN-EXT supports all characters in existing GB, Big5 and
11643 character sets
The escape sequences, shift functions and character sets used in
ISO-2022-CN-EXT text are as follows
Character sets Shift in
--------------------------------------------------------------------
ASCII
GB 2312, GB 12345, CNS 11643-plane-1, ISO-IR-165
GB 7589, GB 13131, CNS 11643-plane-2 SS
GB 7590, GB 13132 or other new GBs,CNS 11643-plane-3 or SS
higher planes of CNS 11643
Note: Currently, there are some GB sets that have not
registered in ISO. Here , , ,
represent the final character that will be assigned
ISO for those sets. These GB sets shall only be used once
final characters are assigned
Zhu, et al Informational [Page 4]
RFC 1922 Chinese Character Encoding March 1996
ESC $ ) A Indicates the bytes following SO are
characters as defined in GB 2312-80,
another SOdesignation
ESC $ * Indicates the two bytes immediately
SS2 is a Chinese character as defined in
7589-87 [GB-7589], until another SS2
ESC $ + Indicates the two bytes immediately
SS3 is a Chinese character as defined in
7590-87 [GB-7590], until another SS3
ESC $ ) Indicates the bytes following SO are as
in GB 12345-90 [GB-12345], until
SOdesignation
ESC $ * Indicates the two bytes immediately
SS2 is a Chinese character as defined in
13131-91 [GB-13131], until
SS2designation
ESC $ + Indicates the two bytes immediately
SS3 is a Chinese character as defined in
13132-91 [GB-13131], until
SS3designation
ESC $ ) E Indicates the bytes following SO are as
in ISO-IR-165 (for details, see section 2.1),
until another SOdesignation
ESC $ ) G Indicates the bytes following SO are as
in CNS 11643-plane-1, until
SOdesignation
ESC $ * H Indicates the two bytes immediately
SS2 is a Chinese character as defined in
11643-plane-2, until another SS2
ESC $ + I Indicates the immediate two bytes following SS
is a Chinese character as defined in
11643-plane-3, until another SS3
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RFC 1922 Chinese Character Encoding March 1996
ESC $ + J Indicates the immediate two bytes following SS
is a Chinese character as defined in
11643-plane-4, until another SS3
ESC $ + K Indicates the immediate two bytes following SS
is a Chinese character as defined in
11643-plane-5, until another SS3
ESC $ + L Indicates the immediate two bytes following SS
is a Chinese character as defined in
11643-plane-6, until another SS3
ESC $ + M Indicates the immediate two bytes following SS
is a Chinese character as defined in
11643-plane-7, until another SS3
As in ISO-2022-CN, each line starts in ASCII, and ends in ASCII,
has its own designation information before any Chinese
appear
The name given to this character encoding is "ISO-2022-CN-EXT".
name is intended to be used as the "charset" parameter in
messages
Content-Type: text/plain; charset=ISO-2022-CN-
The ISO-2022-CN-EXT encoding is also in 7-bit form, so it is
necessary to use a Content-Transfer-Encoding header
Other restrictions are given in the "Formal Syntax
ISO-2022-CN-EXT" (Section 7.2 of this document).
1.4. How to Support Big5 or other internal codesets with ISO-2022-
and ISO-2022-CN-
Since there are many different Chinese internal coding
[CJKINF], such as EUC GB, Big5, CCCII (an encoding for
systems mainly used in Taiwan), GBK (the new standard
for Chinese internal code, also is the codepage for
simplified Chinese Windows 95) etc., ISO-2022-CN and ISO-2022-CN-EXT
which are 7-bit and will not lose information during
among different codesets, facilitate interchange between the
Chinese coding systems in the Internet
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RFC 1922 Chinese Character Encoding March 1996
For instance, ISO-2022-CN and ISO-2022-CN-EXT can be used to
the popular Big5 codeset, because the first two planes of CNS-11643
contain the same Chinese characters as Big5's "common part"
two duplicate characters. By the "common part" we mean the part
is not specific to any Big5 vendor, consisting of 5401
frequently used characters in Big5 range 0xA440-0xC67E, 7652
frequently used characters in Big5 range 0xC940-0xF9D5, and 441
symbols in Big5 range 0xA140-0xA3E0, as defined in Institute
Information Industry's (III) technical report C-26 (see also [Big5]).
The appendix of this document presents a conversion table
converting Big5 into CNS-11643, including specific extensions of
popular vendors. For other extensions, vendors and implementors
Big5 products are ENCOURAGED to create detailed conversion tables,
order to increase interoperability between different coding systems
Public domain software (binary or C source code) for
between Big5 and CNS-11643 is available on many Internet sites.
the time of this writing, the following FTP sites and software
advertised
1) Beijing
ftp://ftp.net.tsinghua.edu.cn/pub/Chinese/convert/big5cns.
(IP address: 166.111.1.6)
2) Xi'an
ftp://ftp.xanet.edu.
/pub/chinese-soft/unix/convert/BeTTY-1.534.tar.
(IP address: 202.112.11.131)
3) Taiwan
ftp://ftp.seed.net.tw/Pub/Chinese/DOS/code-convert/chcode.
(IP address: 140.92.1.65)
4) US
ftp://ftp.ifcss.org/pub/software/unix/convert/BeTTY-1.534.tar.
(IP address: 128.123.1.55)
5) Japan
ftp://etlport.etl.go.jp/pub/iso-2022-cn/convert/big5cns.
(IP address: 192.31.197.99)
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2. 8-bit Chinese encodings: CN-GB and CN-Big
The CN-GB and CN-Big5 MIME charsets are defined below
Note: the use of 8-bit character sets requires the use of
an 8-to-7 Content-Transfer-Encoding mechanism such as "BASE64"
"QUOTED-PRINTABLE" if the network is not 8-bit clean, or the 8-
SMTP extensions [SMTPEXT] with the "8BIT
Content-Transfer-Encoding on 8-bit clean networks. Otherwise,
8-bit message that passes through a 7-bit mailer is likely to
the 8th bit truncated, resulting in an unreadable message
Although "just send 8-bit data" has been common practice in
past, it is incorrect according to the Internet standards
causes interoperability problems
2.1. CN-
E-mail using CN-GB characters is sent in this way
GB 2312-80 characters are used with ASCII characters, not GB 1988-89
[GB-1988].
GB 2312-80 is also 7-bit, to avoid conflicting with ASCII. If
character is from GB 2312-80, the MSB (bit-8) of each byte is set
1, and therefore becomes a 8-bit character. Otherwise, the byte
interpreted as ASCII. This constructs a character set named "
Internal Code".
This method is also adopted in the .gb files in the Internet
To use this character scheme with MIME, CN-GB is used as the
for the charset parameter
Content-Type: text/plain; charset=cn-gb; charset-edition=1980
Note: The "charset-edition" is a new MIME parameter described
section 4.1 of the "Specification" part of this document
GB 12345-90 is the traditional form of GB 2312, the charset
given to this set is CN-GB-12345 with the charset-edition of 1990.
There are also character sets that can only be used with other
sets. For example, GB 8565-88 [GB-8565] is used with GB 2312
some other characters to form the ISO-IR-165 set (also known as
2312 + GB 8565.2). ISO-IR-165 contains all characters from
2312-80 as revised by GB 6345.1-86 and GB 8565.2-88. Its
charset name is CN-GB-ISOIR165 with the charset-edition of 1992.
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RFC 1922 Chinese Character Encoding March 1996
CN-GB-12345 and CN-GB-ISOIR165 support ASCII in a similar manner
CN-GB; the MSB of Chinese characters is set to 1 to distinguish
ASCII
Note: There are some supplementary character sets in GB, i.e.
7589-87, GB 7590-87, GB 13131-91 and GB 13132-91. Normally,
won't be used independently without using GB-2312 or GB-12345,
they are not necessarily to be registered. Characters in
standards could be supported with ISO-2022-CN and ISO-2022-CN-EXT
If, in the future, they need to be used with "charset" names,
is the responsibility of any interested third party (
standardization organization or anybody else) to write
necessary documents and register the charset with the IANA. It
encouraged that the charset names take the form of CN-GB-,
such as CN-GB-12345, where is the GB standard number.
charset-edition should also be given. All CN-GB-
should be coded in 8-bit in a similar fashion to CN-GB
To ensure interoperability, the CN-GB charset should be used
possible instead of a CN-GB- charset
2.2. CN-Big
Big5 is a two-byte character set of traditional Chinese characters
widely used in Taiwan and overseas. E-mail of CN-Big5 is sent
this way
Big5 is used with ASCII. The MSB of ASCII characters is always 0.
The MSB of the first byte of a Big5 character is always 1;
distinguishes it from an ASCII character. The second byte has 8
significant bits. Therefore, CN-Big5 is an 8-bit encoding with
15-bit codespace
To use this character scheme with MIME, CN-Big5 is used as the
for the charset parameter
Content-Type: text/plain; charset=cn-big5; charset-edition=1984
Note: The "charset-edition" is a new MIME parameter described
section 4.1 of the "Specification" part of this document
3. Universal Multilingual Character Set: ISO/IEC-10646/
ISO/IEC 10646 defines a 32bit character space with the intent
encode all characters in the world. Currently, only the lowest 16
plane of ISO 10646, the Basic Multilingual Plane (BMP), is defined
The BMP is code-by-code identical to Unicode [Unicode 1.1].
contains a large repertoire of Chinese characters (it
Zhu, et al Informational [Page 9]
RFC 1922 Chinese Character Encoding March 1996
includes all the characters of GB 2312-80, GB 12345-90, GB 8565-89,
CNS 11643's plane 1 and 2, and part of some other standards)
therefore can be used to transport Chinese characters in the
community. This document does not give any details on how to
this, as this has been done elsewhere. For details of using
with MIME, refer to RFC 1641 [RFC-1641], RFC 1642 [RFC-1642].
assigned names for 10646 set, refer to STD 2--"Assigned Numbers",
which is RFC 1700 [RFC-1700] currently. For more up-to-date
numbers, please check
ftp://ftp.isi.edu/in-notes/iana/assignments/character-
4. Two New MIME
Here we define two new MIME parameters to be used with "charset
parameters
4.1. "charset-edition
This parameter is used after the MIME "charset" parameter, using
digits (AD) to indicate what the year of edition is for the
set standard shown in "charset". Its use is optional
Implementations should ignore this parameter unless
implementation has specific support for that particular character
edition
The reason for defining this parameter is that there are
differences in the defined characters between editions of a
set standard. Sometimes, the difference can not be ignored
otherwise implementations would have problems when processing it
There are only two ways to indicate this difference, in the
MIME syntax. One way is to indicate the edition in the charset name
such as CN-GB-1988-80 (the 1980's edition of GB 1988). The other
is to define a new optional parameter such as "charset-edition".
latter way is better because receiving applications that can
process an older edition can still recognize the character set
offer to display the text in the older edition. This display
have a few mistakes, but it is better than refusing to display
text at all or defaulting to an inappropriate character set such
US-ASCII or ISO-8859-1.
4.2. "charset-extension
This parameter is also used after the MIME "charset" parameter.
is case-insensitive and optional, and any value of this
should be registered in IANA. Unregistered value should start
"x-" as with any MIME extension-token. Implementations should
this parameter unless the implementation has specific support
Zhu, et al Informational [Page 10]
RFC 1922 Chinese Character Encoding March 1996
that particular character set extension
A character set extension has displayed glyphs for code points
are not assigned in the character set, for example, vendor-
extensions of standard character sets. This parameter provides
option of using these extensions. Although character set
may cause interoperability problems, we recognize the existence
such extensions
For example
Content-Type: text/plain; charset=CN-Big5; charset-edition=1984;
charset-extension=ETen-2.00.03-
This may indicate Eten company's extension of Big5: ETen 2.00.03
DOS, assuming that "ETen-2.00.03-DOS" is registered with the IANA..
4.3. Formal Syntax
The following changes and additions are made to the MIME syntax
charset-edition := "charset-edition" "=" 4
; year of edition in four
charset-extension := "charset-extension" "=" extension-
5. Background
5.1. Writing systems and their encodings in Chinese-speaking nations
The mainland provinces of China use simplified Chinese character
daily life. GB is the standard electronic character set. It is
main means for communications between people who share
Chinese characters in the world
Taiwan uses traditional Chinese characters in daily life. CNS-11643
is the formal character set for information interchange in Taiwan
however, Big5, a widely-used character set of traditional
characters, is the de-facto internal code standard in Taiwan
Hong Kong uses traditional Chinese characters in daily life, but
both GB and Big5 in electronic form, because Hong Kong people
communicate with people in all of China's provinces
Singapore seldom uses Chinese characters, and uses the
form when Chinese characters are used. In electronic form,
is more popular, however GB is also used
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RFC 1922 Chinese Character Encoding March 1996
5.2. Miscellaneous information about Chinese character
The GB 1988-89 character set is identical to ISO 646 [ISO-646]
for currency symbol and tilde. The currency symbol and the tilde
replaced by the Yuan sign and the overline. This set is GB's
of ISO 646. This character set and CNS 5205 [CNS-5205] are
encouraged for use in the Internet, since ASCII combined with GB 2312
or CNS 11643-plane 1 and plane 2 contains all the characters in them
The GB 2312-80 character set consists of simplified
characters, digits, and the Latin, Greek and Russian alphabets,
some other symbols; in all, 7445 characters. Each character
represented with two bytes
GB 13000-95 [GB-13000] is GB's variant of ISO 10646. However,
interoperability in the Internet, assigned names for ISO 10646
encouraged instead
Currently both sides of the Taiwan Straits are cooperating closely
promoting the use of ISO 10646's BMP and in continuing
development together with other organizations under ISO
5.3. Miscellaneous implementation
For maximum interoperability, implementations SHOULD at least
sending and receiving ISO-2022-CN. Supporting all
character sets in ISO-2022-CN-EXT is greatly encouraged
To meet the current usage, support of CN-GB (the status quo
simplified Chinese e-mail ) or CN-Big5 (the status quo
traditional Chinese e-mail) may be necessary. However, it is
reliable to send documents directly with these internal codes
therefore sending ISO-2022-CN message is always encouraged
possible
To the maximum extent possible, implementations should be capable
receiving messages in any of the encodings described in
document, even if they only transmit messages in one form
Preferably the implementation should display the characters
glyphs appropriate to the typographic tradition that is implied
the encoding of the received text. Implementation may also
these encodings to the encoding that its platform supports
The human user (not implementor) should try to keep lines within 80
display columns, or, preferably, within 75 (or so) columns, to
insertion of ">" at the beginning of each line in excerpts.
Chinese character takes up two columns, and the shift sequences
Zhu, et al Informational [Page 12]
RFC 1922 Chinese Character Encoding March 1996
not take up any columns. The implementor is reminded that
characters take up two bytes and should not be split in the middle
break lines for displaying, etc
Freely available fonts of Chinese characters
Beijing
ftp://ftp.net.tsinghua.edu.cn/pub/Chinese/fonts
Xi'an
ftp://ftp.xanet.edu.cn/pub/chinese-soft/fonts
Taiwan
ftp://ftp.edu.tw/Chinese/ifcss/software/fonts
ftp://ftp.ntu.edu.tw/Chinese/ifcss/software/fonts
Hong Kong
ftp://ftp.cuhk.hk/pub/chinese/ifcss/software/fonts
Singapore
ftp://ftp.technet.sg:/pub/chinese/fonts
US
ftp://ftp.ifcss.org/pub/software/fonts
http://ccic.ifcss.org/www/pub/software/fonts
6. X.400
X.400 has the ability of carrying different character sets in
message by using the body part "GeneralText" defined
ISO/IEC-10021-7 [ISO-10021].
The X.400 ASN.1 definition of the GeneralText body part is
general-text-body-part EXTENDED-BODY-PART-
PARAMETERS GeneralTextParameters IDENTIFIED BY id-ep-general-
DATA
::= id-et-general-
GeneralTextParameters ::= SET OF
CharacterSetRegistration ::= INTEGER (1..32767)
GeneralTextData ::=
Therefore, to use ISO-2022-CN, set the "CharacterSetRegistration
part as { 6 58 171 172 }, and add an ESC sequence of ESC ( B (
bytes, hexadecimal values: 1B 28 42) before the beginning of
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RFC 1922 Chinese Character Encoding March 1996
line of ISO-2022-CN text
Similarly, to use ISO-2022-CN-EXT, set the registered numbers of
character sets in the "CharacterSetRegistration" part and add ESC (
at the beginning of each line. For the registered numbers,
refer to ISO registry. In addition to the character sets
by ISO-2022-CN, currently registered numbers are
ISO IR 165 (GB 2312+GB 8565.2): 165
CNS 11643-plane 3: 183
CNS 11643-plane 4: 184
CNS 11643-plane 5: 185
CNS 11643-plane 6: 186
CNS 11643-plane 7: 187
176 is the registered number for the BASESET of ISO/IEC 10646-1:1993
UCS-2 with implementation level 3, Escape sequence of ESC % / E (
bytes, hexadecimal values 1B 25 2F 45) indicates starting of
codeset
For CN-GB and CN-Big5 character sets, there are no formal
that could be used in X.400 yet
For detail about X.400 use of character sets, please refer to
1502 [RFC-1502].
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RFC 1922 Chinese Character Encoding March 1996
7. Formal Syntax of ISO-2022-CN and ISO-2022-CN-
The notational conventions used here are identical to those used
RFC 822.
7.1. Formal Syntax of ISO-2022-
body ::= * ( ascii_line / c_line )
ascii_line ::= *char
c_line ::= *char 1*(1*designation 1*(*char 1*c_text *char))
designation ::= SOdesignation / SS2
SOdesignation ::= ESC "$" ")" finalchar_for_
SS2designation ::= ESC "$" "*" finalchar_for_SS
finalchar_for_SO ::= "A" / "G
finalchar_for_SS2 ::= "H
c_text ::= 1* ( SO-SI-segment / SS2segment )
SO-SI-segment ::= SO 1*c_char *designation *c_segment
c_segment ::= 1* ( c_char / SS2segment )
SS2segment ::= SS2 c_
c_char ::= one_of_94 one_of_94
; ( Octal, Decimal.)
ESC ::= ; ( 33, 27.)
SI ::= ; ( 17, 15.)
SO ::= ; ( 16, 14.)
SS2 ::= ; ( 33 116, 27 78.)
one_of_94 ::= ; ( 41-176, 33-126. )
char ::= ; ( 40-177, 30-127. )
Zhu, et al Informational [Page 15]
RFC 1922 Chinese Character Encoding March 1996
7.2. Formal Syntax of ISO-2022-CN-
body ::= * ( ascii_line / c_line )
ascii_line ::= *char
c_line ::= *char 1*(1*designation 1*(*char 1*c_text *char))
designation ::= SOdesignation / SS2designation / SS3
SOdesignation ::= ESC "$" ")" finalchar_for_
SS2designation ::= ESC "$" "*" finalchar_for_SS
SS3designation ::= ESC "$" "+" finalchar_for_SS
finalchar_for_SO ::= "A" / / "G" / "E
finalchar_for_SS2 ::= / / "H
finalchar_for_SS3 ::= / / "I" / "J" / "K" / "L
/ "M
c_text ::= 1* ( SO-SI-segment / SS2segment / SS3segment )
SO-SI-segment ::= SO 1*c_char *designation *c_segment
c_segment ::= 1* ( c_char / SS2segment / SS3segment )
SS2segment ::= SS2 c_
SS3segment ::= SS3 c_
c_char ::= one_of_94 one_of_94
; ( Octal, Decimal.)
ESC ::= ; ( 33, 27.)
SI ::= ; ( 17, 15.)
SO ::= ; ( 16, 14.)
SS2 ::= ; ( 33 116, 27 78.)
SS3 ::= ; ( 33 117, 27 79.)
one_of_94 ::= ; ( 41-176, 33-126.
Zhu, et al Informational [Page 16]
RFC 1922 Chinese Character Encoding March 1996
)
char ::= ; ( 40-177, 30-127.
)
8. Registration of New "charset"s and New MIME
8.1. This document defines the following MIME "charset" names
Chinese text
ISO-2022-CN, ISO-2022-CN-
CN-GB, CN-Big
CN-GB-12345
CN-GB-ISOIR165
8.2. This document defines two new MIME parameters
charset-
charset-
This document is the result of cooperation in APNG-CC, the
Character sub-working group of the I18N/L10N (
and Localization) working group of APNG (Asia-Pacific
Group), coordinator Zhu Haifeng .
membership of APNG-CC consists of individuals from both sides of
Taiwan Strait, HongKong, and from Singapore and other countries.
wish to thank all members of APNG-CC
Prof. Yao Shiquan (Deputy chair of CITS--China Information
Standardization Technical Committee), Ms. Lin Ning (Secretary-
of CITS), Mr. Guo Chengzhong of the Office of the Joint Conference
China Economic Information, and Prof. Zhao Jingrong, Prof.
Jianping, Prof. Li Xing, and Mr. You Yue (Tsinghua University)
other experts from CERNET Expert Committee, Prof. Meng Qingyu (
Computer Software & Technology Services Corporation), Prof.
Jinwen and Mr. Yu Jun (IBM Beijing) gave a lot of support and help
many aspects
Special thanks for the supports towards APNG-CC from Prof.
Tianxing (Chair of CITS).
Prof. Ding ZyKaan from Academia Sinica of Taiwan, and Mr. C. J
Cherng and Mr. C. K. Fan of III (Institute for Information Industry),
Mr. Chang JingShin from Tsinghua University in Hsinchu of Taiwan, Ms
C. C. Hsu from IBM Taiwan and Ms. Tong-Lee Anita Lin from
Zhu, et al Informational [Page 17]
RFC 1922 Chinese Character Encoding March 1996
Taiwan gave a lot of support and contributions in APNG-CC's work.
particular, Ms. C. C. Hsu put much effort towards completing
Appendix of this document
We also wish to thank the following people who contributed in
ways towards this document
Zhang Zhoucai Martin J.
Zhang Ling Kenichi
Zhu Bin Lu
Sun Yufang Nelson
Chen Shuyi Mao
Masataka Ohta Ken
Lua Kim Teng Victor
Stephen G. Simpson Yuan
Liu Huifang Harald T.
Qian Hualin Jiang
Lu Ming Emily
Wu Jian Zhu
Zheng Long Zhang
Yonggang Zhang Feng
Yao
Security
Security issues are not discussed in this memo
Authors'
Zhu Haifeng (HF. Zhu
216 Central Main
Tsinghua
Beijing, 100084
Tel: +86-10-2561144 ext. 3492
Fax: +86-10-2564173
EMail: zhf@net.tsinghua.edu.cn, zhf@net.edu.
Zhu, et al Informational [Page 18]
RFC 1922 Chinese Character Encoding March 1996
Hu Daoyuan (DY. Hu
Tsinghua Networking
Tsinghua
Beijing, 100084
Tel: +86-10-2594016
Fax: +86-10-2564173
EMail: hdy@tsinghua.edu.
Wang Zhiguan (ZG. Wang
Beijing 1101
SubCommitte 2 (SC2)
China Information Technology Standardization Technical
(CITS
Beijing, 100007
Tel: +86-10-4012392
Fax: +86-10-4010601
Kao Tien-cheu (TC. Kao
I.T. Promotion
Institute for Information Industry (III
Tel: +886-2-5631688
Fax: +886-2-563-4209
EMail: tckao@iiidns.iii.org.
Chang Wen-chung (WCH. Chang
Institute for Information Industry (III
Tel: +886-2-7327771
Fax: +886-2-7370188
EMail: chung@iiidns.iii.org.
Zhu, et al Informational [Page 19]
RFC 1922 Chinese Character Encoding March 1996
Mark R.
Networks and Distributed
University of
4545 15th Avenue
Seattle, WA 98105-4527
Tel: +1 (206) 543-5762
Fax: +1 (206) 685-4045
EMail: MRC@CAC.Washington.
Zhu, et al Informational [Page 20]
RFC 1922 Chinese Character Encoding March 1996
Appendix -- Conversion Table for ISO-2022-CN (EXT) and Big
This is a conversion table for the Chinese characters in Big5'
common part and ISO-2022-CN/-EXT, including all the vendor-
characters from Eten, Microsoft and IBM. For conversion source
binary programs for Big5, III provides good on-line services (
site listed in section 1.4), and [CJKINF] is also a good reference
A.1. Big5 (ETen, IBM, and Microsoft version) symbol set
to CNS 11643 Plane 1:
0xA140-0xA1F5 <-> 0x2121-0x2256
0xA1F6 <-> 0x2258
0xA1F7 <-> 0x2257
0xA1F8-0xA2AE <-> 0x2259-0x234
0xA2AF-0xA3BF <-> 0x2421-0x2570
0xA3C0-0xA3E0 <-> 0x4221-0x4241 (ETen and
defined as reserved area
A.2. Big5 (ETen, IBM, and Microsoft version) Level 1 correspondence
CNS 11643-1992 Plane 1:
0xA440-0xACFD <-> 0x4421-0x5322
0xACFE <-> 0x5753
0xAD40-0xAFCF <-> 0x5323-0x5752
0xAFD0-0xBBC7 <-> 0x5754-0x6B4
0xBBC8-0xBE51 <-> 0x6B51-0x6F5
0xBE52 <-> 0x6B50
0xBE53-0xC1AA <-> 0x6F5C-0x7534
0xC1AB-0xC2CA <-> 0x7536-0x7736
0xC2CB <-> 0x7535
0xC2CC-0xC360 <-> 0x7737-0x782
0xC361-0xC3B8 <-> 0x782E-0x7863
0xC3B9 <-> 0x7865
0xC3BA <-> 0x7864
0xC3BB-0xC455 <-> 0x7866-0x7961
0xC456 <-> 0x782
0xC457-0xC67E <-> 0x7962-0x7D4
A.3. Big5 (ETen, IBM, and Microsoft version) Level 2 correspondence
CNS 11643-1992 Plane 2:
0xC940-0xC949 <-> 0x2121-0x212
0xC94A <-> 0x4442 # duplicate of Level 1's 0xA461
0xC94B-0xC96B <-> 0x212B-0x214
0xC96C-0xC9BD <-> 0x214D-0x217
0xC9BE <-> 0x214
0xC9BF-0xC9EC <-> 0x217D-0x224
Zhu, et al Informational [Page 21]
RFC 1922 Chinese Character Encoding March 1996
0xC9ED-0xCAF6 <-> 0x224E-0x2438
0xCAF7 <-> 0x224
0xCAF8-0xD779 <-> 0x2439-0x387
0xD77A <-> 0x3F6
0xD77B-0xDBA6 <-> 0x387E-0x3F69
0xDBA7-0xDDFB <-> 0x3F6B-0x4423
0xDDFC <-> 0x4176 # duplicate of 0xDCD
0xDDFD-0xE8A2 <-> 0x4424-0x554
0xE8A3-0xE975 <-> 0x554C-0x5721
0xE976-0xEB5A <-> 0x5723-0x5A27
0xEB5B-0xEBF0 <-> 0x5A29-0x5B3
0xEBF1 <-> 0x554
0xEBF2-0xECDD <-> 0x5B3F-0x5C69
0xECDE <-> 0x5722
0xECDF-0xEDA9 <-> 0x5C6A-0x5D73
0xEDAA-0xEEEA <-> 0x5D75-0x6038
0xEEEB <-> 0x642
0xEEEC-0xF055 <-> 0x6039-0x6242
0xF056 <-> 0x5D74
0xF057-0xF0CA <-> 0x6243-0x6336
0xF0CB <-> 0x5A28
0xF0CC-0xF162 <-> 0x6337-0x642
0xF163-0xF16A <-> 0x6430-0x6437
0xF16B <-> 0x6761
0xF16C-0xF267 <-> 0x6438-0x6572
0xF268 <-> 0x6934
0xF269-0xF2C2 <-> 0x6573-0x664
0xF2C3-0xF374 <-> 0x664E-0x6760
0xF375-0xF465 <-> 0x6762-0x6933
0xF466-0xF4B4 <-> 0x6935-0x6961
0xF4B5 <-> 0x664
0xF4B6-0xF4FC <-> 0x6962-0x6A4
0xF4FD-0xF662 <-> 0x6A4C-0x6C51
0xF663 <-> 0x6A4
0xF664-0xF976 <-> 0x6C52-0x7165
0xF977-0xF9C3 <-> 0x7167-0x7233
0xF9C4 <-> 0x7166
0xF9C5 <-> 0x7234
0xF9C6 <-> 0x7240
0xF9C7-0xF9D1 <-> 0x7235-0x723
0xF9D2-0xF9D5 <-> 0x7241-0x7244
A.4. Big5 (ETen and IBM Version) specific numeric
correspondence to CNS 11643 Plane 1: (Microsoft version
this area as UDC - User Defined Character
Zhu, et al Informational [Page 22]
RFC 1922 Chinese Character Encoding March 1996
0xC6A1-0xC6BE <-> 0x2621 - 0x263
A.5. Big5 (ETen and IBM Version) specific KangXi
correspondence to CNS 11643 Plane 1: (Microsoft version defined
UDC - User Definable Character
0xC6BF <-> 0x2723
0xC6C0 <-> 0x2724
0xC6C1 <-> 0x2726
0xC6C2 <-> 0x2728
0xC6C3 <-> 0x272
0xC6C4 <-> 0x272
0xC6C5 <-> 0x272
0xC6C6 <-> 0x2734
0xC6C7 <-> 0x2737
0xC6C8 <-> 0x273
0xC6C9 <-> 0x273
0xC6CA <-> 0x2742
0xC6CB <-> 0x2747
0xC6CC <-> 0x274
0xC6CD <-> 0x2753
0xC6CE <-> 0x2754
0xC6CF <-> 0x2755
0xC6D0 <-> 0x2759
0xC6D1 <-> 0x275
0xC6D2 <-> 0x2761
0xC6D3 <-> 0x2766
0xC6D4 <-> 0x2829
0xC6D5 <-> 0x282
0xC6D6 <-> 0x2863
0xC6D7 <-> 0x286
A.6. Big5 (ETen and Microsoft version) specific
correspondence to CNS 11643 Plane 3: (IBM version defined as UDC
0xF9D6 <-> 0x4337
0xF9D7 <-> 0x4F50
0xF9D8 <-> 0x444
0xF9D9 <-> 0x504
0xF9DA <-> 0x2C5
0xF9DB <-> 0x3D7
0xF9DC <-> 0x4B5
A.7. Big5 (ETen version only) specific symbols correspondence to
11643 Plane 4:
0xC879 <-> 0x2123
Zhu, et al Informational [Page 23]
RFC 1922 Chinese Character Encoding March 1996
0xC87B <-> 0x2124
0xC87D <-> 0x212
0xC8A2 <-> 0x2152
A.8. Other Big5 specific symbols which cannot mapping to CNS 11643:
0xC6D8-0xC878 <-> none (ETen and IBM Version
0xC87A <-> none (ETen version only
0xC87C <-> none (ETen version only
0xC87E-0xC8A1 <-> none (ETen version only
0xC8A3-0xC8CC <-> none (ETen version only
0xC8CD-0xC8D3 <-> none (ETen and IBM version
0xF9DD-0xF9FE <-> none (ETen and Microsoft version
Note: However, most of them can be mapped to GB-2312 too.
example, Big5(ETen and IBM version) Hiragana, Katakana,
Cyrillic symbols correspondence to GB-2312:
0xC6E7-0xC77A <-> 0x2421-0x2473 # Japanese
0xC77B-0xC7F2 <-> 0x2521-0x2576 # Japanese
0xC7F3-0xC854 <-> 0xA7A1-0xA7C1 # Cyrillic
0xC855-0xC875 <-> 0xA7D1-0xA7F1 # Cyrillic
Please notice that there are also many symbols that could
supported by GB-2312, for detail, please refer to the ftp sites
section 1.4 of the "Specification" part of this document
Zhu, et al Informational [Page 24]
RFC 1922 Chinese Character Encoding March 1996
[ASCII] American National Standards Institute, "Coded character set
7-bit American National Standard Code for Information Interchange",
ANSI X3.4-1986.
[BIG5] Institute for Information Industry, "Chinese Coded
Set in Computer ", March, 1984
[CJKINF] Ken Lunde, On-line documentation of Chinese/Japanese/
Information Processing, 1995, available at
ftp://ftp.ora.com/pub/examples/nutshell/ujip/doc/cjk.
[CNS-5205] "Information processing: 7-Bit Coded Character Set
Information Interchange", CNS-5205.
[CNS-11643] "Chinese Standard Interchange Code", CNS-11643
1992; "Standard Interchange Code for Generally-Used
Characters", CNS 11643 version 1986.
[GB-1988] "7-bit Coding Character Set for Information Interchange",
GB 1988-89.
[GB-2312] "Coding of Chinese Ideogram Set for Information
Basic Set", GB 2312-80.
[GB-7589] "Code of Chinese Ideograms Set for Information Interchange
the 2nd Supplementary Set", UDC 681.3.048, GB 7589-87.
[GB-7590] "Code of Chinese Ideogram Set for Information Interchange
the 4th Supplementary Set", UDC 681.3.048, GB 7590-87.
[GB-8565] "Information Processing Coded Character Sets for
Communication", UDC 681.3, GB 8565-88.
[GB-12345] "Code of Chinese Ideogram Set for Information
Supplementary Set", GB/T 12345-90.
[GB-13000] "Information Technology: Universal Multiple-Octet
Character Set(UCS) Part 1: Architecture and Basic
Plane", GB13000.1
[GB-13131] "Code of Chinese Ideogram Set for Information Interchange
the 3rd Supplementary Set", GB 13131-91.
[GB-13132] "Code of Chinese Ideogram Set for Information Interchange
the 5th Supplementary Set", GB 13132-91.
Zhu, et al Informational [Page 25]
RFC 1922 Chinese Character Encoding March 1996
[ISO-646] International Organization for Standardization (ISO),
"Information Technology: ISO 7-bit Coded Character Set
Information Interchange", International Standard, Ref. No. ISO/
646:1991.
[ISO-2022] International Organization for Standardization (ISO),
"Information Processing: ISO 7-bit and 8-bit coded character sets
Code extension techniques", International Standard, Ref. No.
2022-1986 (E).
[ISO-10021] Information Technology: Text communication
Message-Oriented Text Interchange Systems (MOTIS), ISO 10021,
1988.
[ISO-10646] ISO/IEC 10646-1:1993(E) Information Technology:
Multiple-octet Coded Character Set (UCS) Part 1: Architecture
Basic Multilingual Plane
[ISOREG] International Organization for Standardization (ISO),
"International Register of Coded Character Sets To Be Used
Escape Sequences".
[MIME-1] Borenstein, N., and Freed, N., "MIME (Multipurpose
Mail Extensions) Part One: Mechanisms for Specifying and
the Format of Internet Message Bodies", RFC 1521, Bellcore, Innosoft
September 1993.
[MIME-2] Moore, K., "MIME (Multipurpose Internet Mail Extensions
Part Two: Message Header Extensions for Non-ASCII Text", RFC 1522,
University of Tennessee, September 1993.
[RFC-822] Crocker, D., "Standard for the Format of ARPA Internet
Messages", STD 11, RFC 822, University of Delaware, August 1982.
[RFC-854] Postel, J., Reynolds J., Telnet Protocol Specification,
854, ISI, May 1983.
[RFC-1036] Horton, M., and Adams, R., "Standard for Interchange
USENET Messages", RFC 1036, AT&T Bell Laboratories, Center
Seismic Studies, December 1987.
[RFC-1468] Murai J., Crispin, M., and van der Poel, E.,
Character Encoding for Internet Messages, June 1993.
[RFC-1557] Choi U., Chon K., and Park H., Korean Character
for Internet Messages, December 1993.
Zhu, et al Informational [Page 26]
RFC 1922 Chinese Character Encoding March 1996
[RFC-1641] Goldsmith D., and Davis M., "Using Unicode with MIME",
1641, Taligent Inc., July 1994
[RFC-1642] Goldsmith D., and Davis M.," UTF-7, A Mail-
Transformation Format of Unicode", July 1994
[RFC-1700] Reynolds J., and Postel J., "Assigned Numbers",RFC 1700,
STD 2, ISI, October 1994
[SMTP] Postel, J. B. "Simple Mail Transfer Protocol", STD 10,
821, USC/Information Sciences Institute, August 1982.
[SMTPEXT] Klensin J., Freed N., Rose M., Stefferud E., and
D., "SMTP Service Extensions", RFC 1651, July 1994.
[Unicode 1.1] "The Unicode Standard, Version 1.1", Addison-Wesley
Reading, MA (to be published; the contents of this standard
currently available by combining [Unicode92], [Unicode93],
[Unicode4]).
[Unicode92] The Unicode Consortium, "The Unicode Standard:
Character Encoding: Version 1.0", Volume 1, Addison-Wesley, Reading
MA, 1992 (ISBN 0-201-56788-1).
[Unicode93] The Unicode Consortium, "The Unicode Standard:
Character Encoding: Version 1.0", Volume 2, Addison-Wesley, Reading
MA, 1992 (ISBN 0-201-60845-6).
[Unicode4] The Unicode Consortium, "The Unicode Standard: Version 1.1
(Prepublication Edition)", Unicode Technical Report #4 (
from the Unicode Consortium).
Zhu, et al Informational [Page 27]
if you see any problems within the linking, don't worry be happy,
this is version 0.1 of the Relevance System and you gotta expect some crappy subroutines sometimes,
just be content we did not write this in Java, which would have made this "bigger and better" HAHAHHA.
RFC documents can be found at I.E.T.F.
Relevance System Copyright © 2002 Spectrum WorldResearch
other technical nosh by ServerMasters Corporation
collaboration of BobX
