draft-ietf-eai-smtpext-01.txt   draft-ietf-eai-smtpext-02.txt 
Network Working Group J. Yao, Ed. Network Working Group J. Yao, Ed.
Internet-Draft W. Mao, Ed. Internet-Draft W. Mao, Ed.
Expires: January 27, 2007 CNNIC Intended status: Informational CNNIC
July 26, 2006 Expires: April 26, 2007 October 23, 2006
SMTP extension for internationalized email address SMTP extension for internationalized email address
draft-ietf-eai-smtpext-01.txt draft-ietf-eai-smtpext-02.txt
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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skipping to change at page 1, line 34 skipping to change at page 1, line 34
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
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This Internet-Draft will expire on January 27, 2007. This Internet-Draft will expire on April 26, 2007.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2006). Copyright (C) The Internet Society (2006).
Abstract Abstract
Internationalized email address includes two parts, the local part Internationalized email address includes two parts, the local part
and the domain part. The way email addresses are used by protocols and the domain part. The ways email addresses are used by protocols
are different from the way domain names are used. The most critical are different from the ways domain names are used. The most critical
difference is that emails are delivered through a chain of peering difference is that emails are delivered through a chain of peering
clients and servers while domain names are resolved by name servers clients and servers while domain names are resolved by name servers
by looking up their own tables. In addition to this, email transport by looking up their own tables. In addition to this, email transport
protocols SMTP and ESMTP provide a negotiation mechanism through protocols SMTP and ESMTP provide a negotiation mechanism through
which clients can make decisions for further processing. So which clients can make decisions for further processing. So
internationalized email address is different from the internationalized email address is different from the
internationalized domain name (IDN). It can be solved by exploiting internationalized domain name (IDN). It can be solved by exploiting
the negotiation mechanism while IDN can not use the negotiation the negotiation mechanism while IDN can not use the negotiation
mechanism. So internationalized email address SHOULD be solved in mechanism. So internationalized email address SHOULD be solved in
the mail transport-level using the negotiation mechanism, which is an the mail transport-level using the negotiation mechanism, which is an
architecturally desirable approach. This document specifies the use architecturally desirable approach. This document specifies the use
of SMTP extension for internationalized email address delivery. It of SMTP extension for internationalized email address delivery. It
also mentions the backward compatible mechanism for downgrade also mentions the backward compatible mechanism for downgrade
procedure, as specified in an associated specification. The protocol procedure, as specified in an associated specification. The protocol
proposed here is MTA-level solution which is feasible, proposed here is MTA-level solution which is feasible,
architecturally more elegant, and not as difficult to deploy in architecturally more elegant, and not as difficult to deploy in
relevant communities. relevant communities.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Role of this specification . . . . . . . . . . . . . . . . 3 1.1. Role of this specification . . . . . . . . . . . . . . . . 4
1.2. Proposal Context . . . . . . . . . . . . . . . . . . . . . 3 1.2. Proposal Context . . . . . . . . . . . . . . . . . . . . . 4
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Mail Transport-level Protocol . . . . . . . . . . . . . . . . 4 2. Mail Transport-level Protocol . . . . . . . . . . . . . . . . 5
2.1. Framework for the Internationalization Extension . . . . . 4 2.1. Framework for the Internationalization Extension . . . . . 5
2.2. The Address Internationalization Service Extension . . . . 4 2.2. The Address Internationalization Service Extension . . . . 5
2.3. Extended Mailbox Address Syntax . . . . . . . . . . . . . 5 2.3. Extended Mailbox Address Syntax . . . . . . . . . . . . . 6
2.4. The ALT-ADDRESS parameter . . . . . . . . . . . . . . . . 6 2.4. The ALT-ADDRESS parameter . . . . . . . . . . . . . . . . 7
2.5. The Suggestion of the Value of the ALT-ADDRESS 2.5. The Suggestion of the Value of the ALT-ADDRESS
parameter . . . . . . . . . . . . . . . . . . . . . . . . 7 parameter . . . . . . . . . . . . . . . . . . . . . . . . 8
2.6. Additional ESMTP Changes and Clarifications . . . . . . . 8 2.6. Body Parts and SMTP Extensions . . . . . . . . . . . . . . 9
2.6.1. The Initial SMTP Exchange . . . . . . . . . . . . . . 8 2.7. Additional ESMTP Changes and Clarifications . . . . . . . 9
2.6.2. Trace Fields . . . . . . . . . . . . . . . . . . . . . 8 2.7.1. The Initial SMTP Exchange . . . . . . . . . . . . . . 10
2.6.3. Mailing List Question . . . . . . . . . . . . . . . . 9 2.7.2. Trace Fields . . . . . . . . . . . . . . . . . . . . . 10
2.6.4. Message Header Label . . . . . . . . . . . . . . . . . 9 2.7.3. Mailing List Question . . . . . . . . . . . . . . . . 10
2.6.5. POP and IMAP . . . . . . . . . . . . . . . . . . . . . 9 2.7.4. Message Header Label . . . . . . . . . . . . . . . . . 10
3. Potential problems . . . . . . . . . . . . . . . . . . . . . . 9 2.7.5. POP and IMAP . . . . . . . . . . . . . . . . . . . . . 10
3.1. Impact to IRI . . . . . . . . . . . . . . . . . . . . . . 9 2.7.6. SMTP Service Extension for DSNs . . . . . . . . . . . 11
3.2. Impact to RFC 2476 and many email related RFC . . . . . . 9 3. Potential problems . . . . . . . . . . . . . . . . . . . . . . 11
4. Implementation Advice . . . . . . . . . . . . . . . . . . . . 10 3.1. Impact to IRI . . . . . . . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 3.2. Impact to RFC 2476 and many email related RFC . . . . . . 11
6. Security considerations . . . . . . . . . . . . . . . . . . . 10 4. Implementation Advice . . . . . . . . . . . . . . . . . . . . 11
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10 6. Security considerations . . . . . . . . . . . . . . . . . . . 12
8.1. Normative References . . . . . . . . . . . . . . . . . . . 10 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
8.2. Informative References . . . . . . . . . . . . . . . . . . 12 8. Change History . . . . . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 8.1. draft-ietf-eai-smtpext: Version 00 . . . . . . . . . . . . 12
Intellectual Property and Copyright Statements . . . . . . . . . . 15 8.2. draft-ietf-eai-smtpext: Version 01 . . . . . . . . . . . . 12
8.3. draft-ietf-eai-smtpext: Version 02 . . . . . . . . . . . . 12
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References . . . . . . . . . . . . . . . . . . . 13
9.2. Informative References . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
Intellectual Property and Copyright Statements . . . . . . . . . . 16
1. Introduction 1. Introduction
1.1. Role of this specification 1.1. Role of this specification
An overview document [EAI-overview] specifies the requirements for, An overview document [EAI-overview] specifies the requirements for,
and components of, full internationalization of electronic mail. and components of, full internationalization of electronic mail.
This document specifies an element of that work, specifically the This document specifies an element of that work, specifically the
definition of an SMTP extension [RFC1869] for the internationalized definition of an SMTP extension [RFC1869] for the internationalized
email address transport delivery. email address transport delivery.
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https://www1.ietf.org/mailman/listinfo/ima for information about https://www1.ietf.org/mailman/listinfo/ima for information about
subscribing. The list's archive is at subscribing. The list's archive is at
http://www1.ietf.org/mail-archive/web/ima/index.html. http://www1.ietf.org/mail-archive/web/ima/index.html.
2. Mail Transport-level Protocol 2. Mail Transport-level Protocol
2.1. Framework for the Internationalization Extension 2.1. Framework for the Internationalization Extension
The following service extension is defined: The following service extension is defined:
1. The name of the SMTP service extension is "Internationalized 1. The name of the SMTP service extension is "Email Address
Email and Extensions"; Internationalization";
2. The EHLO keyword value associated with this extension is 2. The EHLO keyword value associated with this extension is
"UTF8SMTP"; "UTF8SMTP";
3. No parameter values are defined for this EHLO keyword value. In 3. No parameter values are defined for this EHLO keyword value. In
order to permit future (although unanticipated) extensions, the order to permit future (although unanticipated) extensions, the
EHLO response MUST NOT contain any parameters for that keyword. EHLO response MUST NOT contain any parameters for that keyword.
If a parameter appears, the SMTP client that is conformant to If a parameter appears, the SMTP client that is conformant to
this version of this specification MUST treat the ESMTP response this version of this specification MUST treat the ESMTP response
as if the "UTF8SMTP" keyword did not appear. as if the "UTF8SMTP" keyword did not appear.
4. An optional parameters is added to the SMTP MAIL and RCPT 4. An optional parameter is added to the SMTP MAIL and RCPT
commands. The parameter is named as ALT-ADDRESS. The "ALT- commands. The parameter is named as ALT-ADDRESS. The "ALT-
ADDRESS" requires an all-ASCII address as a substitute for the ADDRESS" requires an all-ASCII address as a substitute for the
i18mail addresses that we call the primary address; you can learn i18mail addresses that we call the primary address; you can learn
more in [EAI-overview] or [EAI-downgrading]. The value of "ALT- more in [EAI-overview] or [EAI-downgrading]. The value of "ALT-
ADDRESS" is set by the sender when MUA and the submit ion server ADDRESS" is set by the sender when MUA and the Submission server
have a communication. have a communication.
5. No additional SMTP verbs are defined by this extension. 5. No additional SMTP verbs are defined by this extension.
6. Servers offering this extension MUST provide support for, and 6. Servers offering this extension MUST provide support for, and
announce, the 8BITMIME extension [RFC1652]. announce, the 8BITMIME extension [RFC1652].
2.2. The Address Internationalization Service Extension 2.2. The Address Internationalization Service Extension
An SMTP Server that announces this extension MUST be prepared to An SMTP Server that announces this extension MUST be prepared to
accept a UTF-8 string [RFC3629] in any position in which RFC 2821 accept a UTF-8 string [RFC3629] in any position in which RFC 2821
specifies that a "mailbox" MAY appear. That string MUST be parsed specifies that a "mailbox" MAY appear. That string MUST be parsed
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data or instructions embedded in the address that the ACE process data or instructions embedded in the address that the ACE process
would hide. Some SMTP servers may depend on these specific data or would hide. Some SMTP servers may depend on these specific data or
instructions to do some operations while the local parts applied with instructions to do some operations while the local parts applied with
ACE will lose or hide these data or instructions. SMTP [RFC2821] ACE will lose or hide these data or instructions. SMTP [RFC2821]
prohibits SMTP relays from converting local parts because the level prohibits SMTP relays from converting local parts because the level
of SMTP relays' knowledge on the structure of local parts is assumed of SMTP relays' knowledge on the structure of local parts is assumed
to be zero. However, we can raise the knowledge level by supplying to be zero. However, we can raise the knowledge level by supplying
additional information. Many human users' email addresses do not additional information. Many human users' email addresses do not
have any embedded structure processed by the final delivery MTA. In have any embedded structure processed by the final delivery MTA. In
that case, the sender can specify that these email addresses are safe that case, the sender can specify that these email addresses are safe
to be converted in predefined way. The final delivery SMTP server to be converted in the predefined way. The final delivery SMTP
can revert the addresses even though they are as in all ASCII form. server can revert the addresses even though they are as in all ASCII
Unless the MUA or the submission server clearly knows that the non- form. Unless the MUA or the submission server clearly knows that the
ASCII address can be safely transformed into the all-ASCII address, non-ASCII address can be safely transformed into the all-ASCII
the non-ASCII address should not be transformed because transformed address, the non-ASCII address should not be transformed because
email address may cause some potential problems. transformed email address may cause some potential problems.
This document suggests that the ALT-ADDRESS is set directly by the This document suggests that the ALT-ADDRESS is set directly by the
sender; In default, the all-ASCII address can not be transformed. sender; In default, the all-ASCII address should not be gotten from
the transformation of the non-ASCII address.
2.6. Additional ESMTP Changes and Clarifications 2.6. Body Parts and SMTP Extensions
While this specification requires that servers support the 8BITMIME
extension [RFC1652] to ensure that servers have adequate handling
capability for 8-bit data and to avoid a number of complex encoding
problems, the use of internationalized addresses obviously does not
require non-ASCII body parts in the MIME message. The UTF8SMTP
extension MAY be used with the BODY=8BITMIME parameter if that is
appropriate given the body content or, if the server advertises it
and it is appropriate, with the BODY=BINARYMIME parameter specified
in [RFC3030].
Assuming that the server advertises UTF8SMTP and 8BITMIME, and at
least one non-ASCII address, with or without ALT-ADDRESS, the precise
interpretation of these parameters on the MAIL command is:
1. Headers are in UTF-8, body parts are in ASCII.
2. Headers are in UTF-8, some or all body parts contain 8-bit line-
oriented data.
3. Headers are in UTF-8, some or all body parts contain binary data
without restriction as to line lengths or delimiters.
2.7. Additional ESMTP Changes and Clarifications
The mail transport process involves addresses ("mailboxes") and The mail transport process involves addresses ("mailboxes") and
domain names in contexts in addition to the MAIL and RCPT commands domain names in contexts in addition to the MAIL and RCPT commands
and extended alternatives to them. In general, the rule is that, and extended alternatives to them. In general, the rule is that,
when RFC 2821 specifies a mailbox, this document expects UTF-8 to be when RFC 2821 specifies a mailbox, this document expects UTF-8 to be
used for the entire string; when RFC 2821 specifies a domain name, used for the entire string; when RFC 2821 specifies a domain name,
the name SHOULD be in punycode form if its raw form is non-ASCII. the name SHOULD be in punycode form if its raw form is non-ASCII.
The following subsections list and discuss all of the relevant cases. The following subsections list and discuss all of the relevant cases.
Support and use of this extension requires support for 8BITMIME. It Support and use of this extension requires support for 8BITMIME. It
means that 8BITMIME MUST be advertised by the UTF8SMTP capability means that 8BITMIME MUST be advertised by the UTF8SMTP capability
SMTP server. SMTP server.
2.6.1. The Initial SMTP Exchange 2.7.1. The Initial SMTP Exchange
When an SMTP or ESMTP connection is opened, the server sends a When an SMTP or ESMTP connection is opened, the server sends a
"banner" response consisting of the 220 reply code and some "banner" response consisting of the 220 reply code and some
information. The client then sends the EHLO command. Since the information. The client then sends the EHLO command. Since the
client cannot know whether the server supports UTF8SMTP until after client cannot know whether the server supports UTF8SMTP until after
it receives the response from EHLO, any domain names that appear in it receives the response from EHLO, any domain names that appear in
this dialogue, or in responses to EHLO, MUST be in hostname form, this dialogue, or in responses to EHLO, MUST be in hostname form,
i.e., internationalized ones MUST be in punycode form. i.e., internationalized ones MUST be in punycode form.
2.6.2. Trace Fields 2.7.2. Trace Fields
Internationalized domain names in Received fields MUST be transmitted Internationalized domain names in Received fields MUST be transmitted
in the punycode form. Addresses in "for" clauses need further in the punycode form. Addresses in "for" clauses need further
examination and might be treated differently depending on [EAI- examination and might be treated differently depending on
utf8header]. The reasoning in the introductory portion of [EAI- [EAI-utf8header]. The reasoning in the introductory portion of
overview] strongly suggests that these addresses be in UTF-8 form, [EAI-overview] strongly suggests that these addresses be in UTF-8
rather than some specialized encoding. form, rather than some specialized encoding.
2.6.3. Mailing List Question 2.7.3. Mailing List Question
How a mixture of traditional and internationalized addresses on a How a mixture of traditional and internationalized addresses on a
mailing list will impact message flows, error reports, and delivery mailing list will impact message flows, error reports, and delivery
notifications in all plausible combinations of UTF8SMTP capability notifications in all plausible combinations of UTF8SMTP capability
and un-capability servers is discussed and specified in the [EAI- and un-capability servers is discussed and specified in the
mailing list]. [EAI-mailing list].
2.6.4. Message Header Label 2.7.4. Message Header Label
The message header label MAY be used to identify and distinguish the The message header label MAY be used to identify and distinguish the
i18mail message from the normal message when SMTP messages are i18mail message from the normal message when SMTP messages are
transmitted on wire. This issue is discussed and specified in [EAI- transmitted on wire. This issue is discussed and specified in
utf8header]. [EAI-utf8header].
2.6.5. POP and IMAP 2.7.5. POP and IMAP
While SMTP mainly takes care of the transportation of messages and While SMTP mainly takes care of the transportation of messages and
the header fields on wire, POP essentially handles the retrieval of the header fields on wire, POP essentially handles the retrieval of
mail objects from the server by a client. In order to use mail objects from the server by a client. In order to use
internationalized user names based on i18mail for the retrieval of internationalized user names based on i18mail for the retrieval of
messages from a mail server using the POP protocol, a new capability messages from a mail server using the POP protocol, a new capability
SHOULD be introduced following the POP3 extension mechanism SHOULD be introduced following the POP3 extension mechanism
[RFC2449]. This is discussed and specified in the [EAI-pop]. [RFC2449]. This is discussed and specified in the [EAI-pop].
IMAP [RFC3501] uses the traditional user name which is based on IMAP [RFC3501] uses the traditional user name which is based on
ASCII. IMAP SHOULD be updated to support the internationalized user ASCII. IMAP SHOULD be updated to support the internationalized user
names based on i18mail for the retrieval of messages from a mail names based on i18mail for the retrieval of messages from a mail
server. This is discussed and specified in the [EAI-imap]. server. This is discussed and specified in the [EAI-imap].
2.7.6. SMTP Service Extension for DSNs
How to facilitate the use of SMTP Service Extension for DSNs
[RFC3461] in the work of EAI will be addressed in the [EAI-dsn].
3. Potential problems 3. Potential problems
3.1. Impact to IRI 3.1. Impact to IRI
The mailto: schema in IRI [RFC3987] MAY need to be modified when EAI The mailto: schema in IRI [RFC3987] MAY need to be modified when EAI
is standardized. is standardized.
3.2. Impact to RFC 2476 and many email related RFC 3.2. Impact to RFC 2476 and many email related RFC
The EAI protocol will impact on many email related RFC such as The EAI protocols will impact on many email related RFC documents
Message Submission [RFC2476] and SMTP Service Extension for DSNs such as Message Submission [RFC2476]. These protocols SHOULD be
[RFC3461]. These protocol SHOULD be considered when implementing the considered when implementing the EAI protocol.
EAI protocol.
4. Implementation Advice 4. Implementation Advice
In the absence of this extension, SMTP clients and servers are In the absence of this extension, SMTP clients and servers are
constrained to using only those addresses permitted by RFC 2821. The constrained to using only those addresses permitted by RFC 2821. The
local parts of those addresses MAY be made up of any ASCII local parts of those addresses MAY be made up of any ASCII
characters, although certain of them MUST be quoted as specified characters, although certain of them MUST be quoted as specified
there. It is notable in an internationalization context that there there. It is notable in an internationalization context that there
is a long history on some systems of using overstruck ASCII is a long history on some systems of using overstruck ASCII
characters (a character, a backspace, and another character) within a characters (a character, a backspace, and another character) within a
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7. Acknowledgements 7. Acknowledgements
Much of the text in the initial version of this document was derived Much of the text in the initial version of this document was derived
or copied from [Klensin-emailaddr] with the permission of the author. or copied from [Klensin-emailaddr] with the permission of the author.
Significant comments and suggestions were received from Xiaodong LEE, Significant comments and suggestions were received from Xiaodong LEE,
Nai-Wen Hsu, Yangwoo KO, Yoshiro YONEYA, and other members of the JET Nai-Wen Hsu, Yangwoo KO, Yoshiro YONEYA, and other members of the JET
team and were incorporated into the document. Special thanks to team and were incorporated into the document. Special thanks to
those contributors for this version of document, those includes (but those contributors for this version of document, those includes (but
not limited to) John C Klensin, Charles Lindsey, Dave Crocker, Harald not limited to) John C Klensin, Charles Lindsey, Dave Crocker, Harald
Tveit Alvestrand, Marcos Sanz, Chris Newman, Martin Duerst, Edmon Tveit Alvestrand, Marcos Sanz, Chris Newman, Martin Duerst, Edmon
Chung, Tony Finch. Chung, Tony Finch, Kari Hurtta.
8. References 8. Change History
8.1. Normative References [[anchor20: REMOVE THIS: This section is used for tracking the update
of this document. It may be useful to retain parts of it to
facilitate establishing dates and documents for the history of this
work.]]
8.1. draft-ietf-eai-smtpext: Version 00
This version supercedes draft-yao-ima-smtpext-03.txt. It refines the
ABNF definiton of the internationalized email address. It represents
as the EAI working group document.
8.2. draft-ietf-eai-smtpext: Version 01
o Upgraded to reflect discussions during IETF 66.
o Remove the atomic parameter.
o Add the new section of "the Suggestion of the value of the ALT-
ADDRESS parameter".
8.3. draft-ietf-eai-smtpext: Version 02
o Upgraded to reflect the recent discussion of the ima@ietf.org
mailing list.
o Add the section of "Body Parts and SMTP Extensions".
o Add the new section of "Change History".
o Add the subsection about SMTP extensions for DSN.
9. References
9.1. Normative References
[ASCII] American National Standards Institute (formerly United [ASCII] American National Standards Institute (formerly United
States of America Standards Institute), "USA Code for States of America Standards Institute), "USA Code for
Information Interchange", ANSI X3.4-1968, 1968. Information Interchange", ANSI X3.4-1968, 1968.
ANSI X3.4-1968 has been replaced by newer versions with ANSI X3.4-1968 has been replaced by newer versions with
slight modifications, but the 1968 version remains slight modifications, but the 1968 version remains
definitive for the Internet. definitive for the Internet.
[EAI-downgrading] [EAI-downgrading]
YONEYA, Y., Ed. and K. Fujiwara, Ed., "Downgrading YONEYA, Y., Ed. and K. Fujiwara, Ed., "Downgrading
mechanism for Internationalized eMail Address (IMA)", mechanism for Internationalized eMail Address (IMA)",
draft-ietf-eai-downgrade-00 (work in progress), draft-ietf-eai-downgrade-02 (work in progress),
October 2005. August 2006.
[EAI-dsn] Newman, C., "SMTP extensions for DSNs", 12 2006, <http://
www.ietf.org/internet-drafts/draft-ietf-eai-dsn-00.txt>.
[EAI-imap] [EAI-imap]
Resnick, P. and C. Newman, "Considerations for IMAP in Resnick, P. and C. Newman, "Considerations for IMAP in
Conjunction with Email Address Internationalization", Conjunction with Email Address Internationalization",
draft-ietf-eai-imap-utf8-00 (work in progress), May 2006. draft-ietf-eai-imap-utf8-00 (work in progress), May 2006.
[EAI-mailing list] [EAI-mailing list]
Chung, E., "Mailing Lists and Internationalized Email Chung, E., "Mailing Lists and Internationalized Email
Addresses", June 2006. Addresses", June 2006.
Forthcoming Forthcoming
[EAI-overview] [EAI-overview]
Klensin, J. and Y. Ko, "Overview and Framework for Klensin, J. and Y. Ko, "Overview and Framework for
Internationalized Email", draft-ietf-eai-framework-01.txt Internationalized Email", draft-ietf-eai-framework-02.txt
(work in progress), June 2006. (work in progress), October 2006.
[EAI-pop] Newman, C., "POP3 Support for UTF-8", June 2006, <http:// [EAI-pop] Newman, C., "POP3 Support for UTF-8", June 2006, <http://
www.ietf.org/internet-drafts/draft-ietf-eai-pop-00.txt>. www.ietf.org/internet-drafts/draft-ietf-eai-pop-00.txt>.
[EAI-utf8header] [EAI-utf8header]
Yeh, J., "Transmission of Email Headers in UTF-8 Yeh, J., "Transmission of Email Headers in UTF-8
Encoding", draft-ietf-eai-utf8headers-00.txt (work in Encoding", draft-ietf-eai-utf8headers-01.txt (work in
progress), June 2006. progress), August 2006.
[RFC1652] Klensin, J., Freed, N., Rose, M., Stefferud, E., and D. [RFC1652] Klensin, J., Freed, N., Rose, M., Stefferud, E., and D.
Crocker, "SMTP Service Extension for 8bit-MIMEtransport", Crocker, "SMTP Service Extension for 8bit-MIMEtransport",
RFC 1652, July 1994. RFC 1652, July 1994.
[RFC1869] Klensin, J., Freed, N., Rose, M., Stefferud, E., and D. [RFC1869] Klensin, J., Freed, N., Rose, M., Stefferud, E., and D.
Crocker, "SMTP Service Extensions", STD 10, RFC 1869, Crocker, "SMTP Service Extensions", STD 10, RFC 1869,
November 1995. November 1995.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2449] Gellens, R., Newman, C., and L. Lundblade, "POP3 Extension [RFC2449] Gellens, R., Newman, C., and L. Lundblade, "POP3 Extension
Mechanism", RFC 2449, November 1998. Mechanism", RFC 2449, November 1998.
[RFC2476] Gellens, R. and J. Klensin, "Message Submission", [RFC2476] Gellens, R. and J. Klensin, "Message Submission",
skipping to change at page 12, line 12 skipping to change at page 14, line 23
[RFC2476] Gellens, R. and J. Klensin, "Message Submission", [RFC2476] Gellens, R. and J. Klensin, "Message Submission",
RFC 2476, December 1998. RFC 2476, December 1998.
[RFC2821] Klensin, J., "Simple Mail Transfer Protocol", RFC 2821, [RFC2821] Klensin, J., "Simple Mail Transfer Protocol", RFC 2821,
April 2001. April 2001.
[RFC2822] Resnick, P., "Internet Message Format", RFC 2822, [RFC2822] Resnick, P., "Internet Message Format", RFC 2822,
April 2001. April 2001.
[RFC3030] Vaudreuil, G., "SMTP Service Extensions for Transmission
of Large and Binary MIME Messages", RFC 3030,
December 2000.
[RFC3454] Hoffman, P. and M. Blanchet, "Preparation of [RFC3454] Hoffman, P. and M. Blanchet, "Preparation of
Internationalized Strings ("stringprep")", RFC 3454, Internationalized Strings ("stringprep")", RFC 3454,
December 2002. December 2002.
[RFC3461] Moore, K., "Simple Mail Transfer Protocol (SMTP) Service [RFC3461] Moore, K., "Simple Mail Transfer Protocol (SMTP) Service
Extension for Delivery Status Notifications (DSNs)", Extension for Delivery Status Notifications (DSNs)",
RFC 3461, January 2003. RFC 3461, January 2003.
[RFC3463] Vaudreuil, G., "Enhanced Mail System Status Codes", [RFC3463] Vaudreuil, G., "Enhanced Mail System Status Codes",
RFC 3463, January 2003. RFC 3463, January 2003.
skipping to change at page 12, line 43 skipping to change at page 15, line 9
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", RFC 3629, November 2003. 10646", RFC 3629, November 2003.
[RFC3987] Duerst, M. and M. Suignard, "Internationalized Resource [RFC3987] Duerst, M. and M. Suignard, "Internationalized Resource
Identifiers (IRIs)", RFC 3987, January 2005. Identifiers (IRIs)", RFC 3987, January 2005.
[RFC4234] Crocker, D. and P. Overell, "Augmented BNF for Syntax [RFC4234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 4234, October 2005. Specifications: ABNF", RFC 4234, October 2005.
8.2. Informative References 9.2. Informative References
[Klensin-emailaddr] [Klensin-emailaddr]
Klensin, J., "Internationalization of Email Addresses", Klensin, J., "Internationalization of Email Addresses",
draft-klensin-emailaddr-i18n-03 (work in progress), draft-klensin-emailaddr-i18n-03 (work in progress),
July 2005. July 2005.
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail [RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part One: Format of Internet Message Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996. Bodies", RFC 2045, November 1996.
skipping to change at page 15, line 5 skipping to change at page 16, line 5
Email: yaojk@cnnic.cn Email: yaojk@cnnic.cn
Wei MAO (editor) Wei MAO (editor)
CNNIC CNNIC
No.4 South 4th Street, Zhongguancun No.4 South 4th Street, Zhongguancun
Beijing Beijing
Phone: +86 10 58813055 Phone: +86 10 58813055
Email: mao@cnnic.cn Email: mao@cnnic.cn
Intellectual Property Statement Full Copyright Statement
Copyright (C) The Internet Society (2006).
This document is subject to the rights, licenses and restrictions
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This document and the information contained herein are provided on an
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OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
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Intellectual Property
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
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skipping to change at page 15, line 29 skipping to change at page 16, line 45
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ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Copyright Statement
Copyright (C) The Internet Society (2006). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
Acknowledgment Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is provided by the IETF
Internet Society. Administrative Support Activity (IASA).
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