ids/2/590.txt

-Network Working Group                                          R. Fajman
-Request for Comments: 2298                 National Institutes of Health
-Category: Standards Track                                     March 1998
+Network Working Group                                     T. Hansen, Ed.
+Request for Comments: 3798                             AT&T Laboratories
+Obsoletes: 2298                                        G. Vaudreuil, Ed.
+Updates: 3461, 2046                                  Lucent Technologies
+Category: Standards Track                                       May 2004
 
 
-                      An Extensible Message Format
-                 for Message Disposition Notifications
+                   Message Disposition Notification
 
 Status of this Memo
 
    This document specifies an Internet standards track protocol for the
    Internet community, and requests discussion and suggestions for
    improvements.  Please refer to the current edition of the "Internet
    Official Protocol Standards" (STD 1) for the standardization state
    and status of this protocol.  Distribution of this memo is unlimited.
 
 Copyright Notice
 
-   Copyright (C) The Internet Society (1998).  All Rights Reserved.
+   Copyright (C) The Internet Society (2004).  All Rights Reserved.
 
 Abstract
 
    This memo defines a MIME content-type that may be used by a mail user
-   agent (UA) or electronic mail gateway to report the disposition of a
-   message after it has been sucessfully delivered to a recipient.  This
-   content-type is intended to be machine-processable.  Additional
+   agent (MUA) or electronic mail gateway to report the disposition of a
+   message after it has been successfully delivered to a recipient.
+   This content-type is intended to be machine-processable.  Additional
    message headers are also defined to permit Message Disposition
    Notifications (MDNs) to be requested by the sender of a message.  The
    purpose is to extend Internet Mail to support functionality often
    found in other messaging systems, such as X.400 and the proprietary
    "LAN-based" systems, and often referred to as "read receipts,"
-   "acknowledgements," or "receipt notifications."  The intention is to
+   "acknowledgements", or "receipt notifications."  The intention is to
-   do this while respecting the privacy concerns that have often been
+   do this while respecting privacy concerns, which have often been
    expressed when such functions have been discussed in the past.
 
    Because many messages are sent between the Internet and other
    messaging systems (such as X.400 or the proprietary "LAN-based"
    systems), the MDN protocol is designed to be useful in a multi-
    protocol messaging environment.  To this end, the protocol described
    in this memo provides for the carriage of "foreign" addresses, in
    addition to those normally used in Internet Mail.  Additional
    attributes may also be defined to support "tunneling" of foreign
    notifications through Internet Mail.
 
 Table of Contents
 
-   1.   Introduction ............................................  2
-   2.   Requesting Message Disposition Notifications ............  3
-   3.   Format of a Message Disposition Notification ............  7
-   4.   Timeline of events ...................................... 17
-   5.   Conformance and Usage Requirements ...................... 18
-   6.   Security Considerations ................................. 19
-   7.   Collected Grammar ....................................... 20
-   8.   Guidelines for Gatewaying MDNs .......................... 22
-   9.   Example ................................................. 24
-   10.  IANA Registration Forms ................................. 25
-   11.  Acknowledgments ......................................... 26
-   12.  References .............................................. 26
-   13.  Author's Address ........................................ 27
-   14.  Copyright ............................................... 28
+   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
+       1.1.  Purposes . . . . . . . . . . . . . . . . . . . . . . . .  3
+       1.2.  Requirements . . . . . . . . . . . . . . . . . . . . . .  3
+       1.3.  Terminology. . . . . . . . . . . . . . . . . . . . . . .  4
+   2.  Requesting Message Disposition Notifications . . . . . . . . .  4
+       2.1.  The Disposition-Notification-To Header . . . . . . . . .  4
+       2.2.  The Disposition-Notification-Options Header. . . . . . .  6
+       2.3.  The Original-Recipient Header. . . . . . . . . . . . . .  7
+       2.4.  Use with the Message/Partial Content Type. . . . . . . .  8
+   3.  FORMAT OF A MESSAGE DISPOSITION NOTIFICATION . . . . . . . . .  8
+       3.1.  The message/disposition-notification content-type. . . .  9
+       3.2.  Message/disposition-notification Fields. . . . . . . . . 11
+       3.3.  Extension-fields . . . . . . . . . . . . . . . . . . . . 16
+   4.  Timeline of Events . . . . . . . . . . . . . . . . . . . . . . 17
+   5.  Conformance and Usage Requirements . . . . . . . . . . . . . . 18
+   6.  Security Considerations. . . . . . . . . . . . . . . . . . . . 19
+       6.1.  Forgery. . . . . . . . . . . . . . . . . . . . . . . . . 19
+       6.2.  Privacy. . . . . . . . . . . . . . . . . . . . . . . . . 19
+       6.3.  Non-Repudiation. . . . . . . . . . . . . . . . . . . . . 20
+       6.4.  Mail Bombing . . . . . . . . . . . . . . . . . . . . . . 20
+   7.  Collected Grammar. . . . . . . . . . . . . . . . . . . . . . . 20
+   8.  Guidelines for Gatewaying MDNS . . . . . . . . . . . . . . . . 22
+       8.1.  Gatewaying from other mail systems to MDNs . . . . . . . 23
+       8.2.  Gatewaying from MDNs to other mail systems . . . . . . . 23
+       8.3.  Gatewaying of MDN-requests to other mail systems . . . . 24
+   9.  Example. . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
+   10. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 25
+       10.1. Disposition-Notification-Options header parameter names. 26
+       10.2. Disposition modifier names . . . . . . . . . . . . . . . 26
+       10.3. MDN extension field names. . . . . . . . . . . . . . . . 26
+   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 27
+   12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 27
+       12.1. Normative References . . . . . . . . . . . . . . . . . . 27
+       12.2. Informative References . . . . . . . . . . . . . . . . . 28
+   Appendix A - Changes from RFC 2298 . . . . . . . . . . . . . . . . 29
+   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 29
+   Full Copyright Statement . . . . . . . . . . . . . . . . . . . . . 30
 
*1.  Introduction
 
-   This memo defines a MIME content-type [5] for message
+   This memo defines a [RFC-MIME-MEDIA] content-type for message
disposition notifications (MDNs).  An MDN can be used to notify the
sender of a message of any of several conditions that may occur after
successful delivery, such as display of the message contents,
printing of the message, deletion (without display) of the message,
or the recipient's refusal to provide MDNs.  The
"message/disposition-notification" content-type defined herein is
intended for use within the framework of the "multipart/report"
-   content type defined in RFC 1892 [7].
+   content type defined in [RFC-REPORT].

> This memo defines the format of the notifications and the 
-   RFC 822 headers used to request them.
+   [RFC-MSGFMT] headers used to request them.

-   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
-   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
-   document are to be interpreted as described in RFC 2119.
 
-1.1 Purposes
+1.1.  Purposes

>   The MDNs defined in this memo are expected to serve several purposes:

>   (a)  Inform human beings of the disposition of messages after
-        succcessful delivery, in a manner which is largely independent of
+        successful delivery, in a manner that is largely independent of
human language;

>   (b)  Allow mail user agents to keep track of the disposition of
messages sent, by associating returned MDNs with earlier message
transmissions;

    (c)  Convey disposition notification requests and disposition
         notifications between Internet Mail and "foreign" mail systems
         via a gateway;
 
    (d)  Allow "foreign" notifications to be tunneled through a MIME-
         capable message system and back into the original messaging
         system that issued the original notification, or even to a third
         messaging system;
 
    (e)  Allow language-independent, yet reasonably precise, indications
         of the disposition of a message to be delivered.
 
-1.2 Requirements
+1.2.  Requirements
 
    These purposes place the following constraints on the notification
    protocol:
 
-   (a)  It must be readable by humans, as well as being machine-parsable.
+   (a)  It must be readable by humans, and must be machine-parsable.

    (b)  It must provide enough information to allow message senders (or
         their user agents) to unambiguously associate an MDN with the
         message that was sent and the original recipient address for
-        which the MDN is issued (if such information is available),
+        which the MDN was issued (if such information is available),
even if the message was forwarded to another recipient address.
 
    (c)  It must also be able to describe the disposition of a message
         independent of any particular human language or of the
         terminology of any particular mail system.
 
-   (d)  The specification must be extensible in order to accomodate
+   (d)  The specification must be extensible in order to accommodate
         future requirements.
 
+1.3.  Terminology
+
+   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+   document are to be interpreted as described in [RFC-KEYWORDS].
+
+   All syntax descriptions use the ABNF specified by [RFC-MSGFMT], in
+   which the lexical tokens (used below) are defined: "atom", "CRLF",
+   "mailbox", "msg-id", and "text".  The following lexical tokens are
+   defined in the definition of the Content-Type header in [RFC-MIME-
+   BODY]: "attribute" and "value".

* 2.  Requesting Message Disposition Notifications
>   Message disposition notifications are requested by including a
Disposition-Notification-To header in the message.  Further
information to be used by the recipient's [INS(rfc3798)[M]]UA in generating the MDN
may be provided by [INS(rfc3798)[also]] including Original-Recipient and/or
Disposition-Notification-Options headers in the message.

メッセージ配置通知はメッセージに [CODE(822)[[[Disposition-Notification-To]]]]
頭を含めることにより要求します。[[受信者]]の [[MUA]] が [[MDN]]
を生成するに当たって使用する更なる情報をメッセージの
[CODE(822)[[[Original-Recipient]]]] 頭や
[CODE(822)[Disposition-Notification-Option]]]]
頭も含めることにより提供しても構いません。

* 2.1[INS(rfc3798)[.]]  The Disposition-Notification-To Header
>   A request [DEL(rfc3798)[that]] [INS(rfc3798)[for]] 
the receiving user agent [INS(rfc3798)[to]] issue message disposition
notifications is made by placing a Disposition-Notification-To header
into the message.  The syntax of the 
header, [DEL(rfc3798)[using the ABNF of RFC 822 [2],]] is

[[受信]]した[[利用者エージェント]]がメッセージ配置通知を発行するようにとの[[要求]]は[[メッセージ]]に
[CODE(822)[Disposition-Notification-To]] [[頭]]を入れることにより行います。
この頭の構文は次の通りです。

>
-   mdn-request-header = "Disposition-Notification-To" ":" [DEL(rfc3798)[1#mailbox]] [INS(rfc3798)[mailbox *("," mailbox)]]

[DEL(rfc3798)[
>   The mailbox token is as specified in RFC 822 [2].

[[字句]] [CODE(ABNF)[[[mailbox]]]] は [[RFC 822]] で規定されているものです。
]DEL]

>   The presence of a Disposition-Notification-To header in a message is
merely a request for an MDN.  The recipients' user agents are always
free to silently ignore such a request.  Alternatively, an explicit
denial of the request for information about the disposition of the
message may be sent using the "denied" disposition in an MDN.

メッセージにおける [CODE(822)[Disposition-Notification-To]]
頭の存在は単なる [[MDN]] の要求です。
[[受信者]]の[[利用者エージェント]]はこの要求を常に黙って自由に無視できます。
その代わりに [[MDN]] の [CODE(MDN)[[[denied]]]] 
配置を使ってメッセージの配置に関する情報の要求の拒絶を明示的に送信しても構いません。

>   An MDN MUST NOT itself have a Disposition-Notification-To header. 
An MDN MUST NOT be generated in response to an MDN.

[[MDN]] 自体は [CODE(822)[Disposition-Notigication-To]] 頭を持っていては'''なりません'''。
[[MDN]] を [[MDN]] への[[応答]]として生成しては'''なりません'''。

>   [DEL(rfc3798)[At most one MDN may be issued on behalf of each particular recipient by their user agent.]] [INS(rfc3798)[A user agent MUST NOT issue more than one MDN on behalf of each particular recipient.]]  
That is, once an MDN has been issued on behalf
of a recipient, no further MDNs may be issued on behalf of that
recipient, even if another disposition is performed on the message.
However, if a message is forwarded, an MDN may have [INS(rfc3798)[been]] issued for
the recipient doing the forwarding and the recipient of the forwarded
message may also cause an MDN to be generated.

[[利用者エージェント]]はそれぞれの[[受信者]]について複数回 [[MDN]]
を発行しては'''なりません'''。つまり、ある受信者について1度 [[MDN]]
が発行されたら、以後そのメッセージに別の配置が取られたとしても [[MDN]] 
をその受信者について再度発行してはいけません。
但し、メッセージが[[転送]]された場合は転送を行った受信者について [[MDN]]
を発行しても構いませんし、転送メッセージの受信者も [[MDN]]
を生成して構いません。

>  While Internet standards normally do not specify the behavior of user
interfaces, it is strongly recommended that the user agent obtain the
user's consent before sending an MDN.  This consent could be obtained
for each message through some sort of prompt or dialog box, or
globally through the user's setting of a preference.  The user might
also indicate globally that MDNs are [INS(rfc3798)[to]] never [DEL(rfc3798)[to]] be sent or that a
"denied" MDN is always sent in response to a request for an MDN.

インターネット規格は通常[[利用者界面]]の動作を規定しませんが、
[[利用者エージェント]]は [[MDN]] を送信する前に[[利用者]]の同意を得ることを強く推奨します。
この同意は問合せや[[対話箱]]のようなもので得ることもできましょうし、
利用者の設定であらかじめ得ておくことも可能でしょう。
利用者は [[MDN]] を絶対に送らないことや [CODE(MDN)[[[denied]]]] [[MDN]]
を常に [[MDN]] 要求に対する応答として送信することを望むかもしれません。

>    MDNs SHOULD NOT be sent automatically if the address in the
Disposition-Notification-To header differs from the address in the
Return-Path header (see [DEL(rfc3798)[RFC 822 [2] ]] [INS(rfc3798)[ [RFC-MSGFMT] ]]).  In this case, confirmation
from the user SHOULD be obtained, if possible.  If obtaining consent
is not possible (e.g., because the user is not online at the time),
then an MDN SHOULD NOT be sent.

[CODE(822)[Disposition-Notification-To]] 頭の[[番地]]が
[CODE(822)[[[Return-Path]]]] 頭の番地と異なる場合には [[MDN]]
を自動的に送信する'''べきではありません'''。こも場合、
可能なら利用者に確認する'''べきです'''。同意を得ることが不可能な場合
(例えば利用者がその時[[線上]]でない場合) は
[[MDN]] を送る'''べきではありません'''。

>    Confirmation from the user SHOULD be obtained (or no MDN sent) if
there is no Return-Path header in the message, or if there is more
than one distinct address in the Disposition-Notification-To header.

メッセージに [CODE(822)[[[Return-Path]]]]
頭がない場合や [CODE(822)[Disposition-Notification-To]]
頭に複数の異なる番地が指定されている場合には利用者に確認を取る
(か [[MDN]] を送らない) '''べきです'''。

>    The comparison of the addresses should be done using only the 
addr-spec (local-part "@" domain) portion, excluding any phrase and route.
The comparison MUST be case-sensitive for the local-part and 
case-insensitive for the domain part.

[[番地]]の[[比較]]は [CODE(ABNF)[[[addr-spec]]]]
([CODE(ABNF)[[[local-part]] @" [[domain]]]])
の部分のみで [CODE(ABNF)[[[phrase]]]] や [CODE(ABNF)[[[route]]]]
は除外して行うべきです。比較は [CODE(ABNF)[[[local-part]]]]
は大文字・小文字を区別し、 [CODE(ABNF)[[[domain]]]] 部は大文字・
小文字を区別せずに行わなければ'''なりません'''。

>    If the message contains more than one Return-Path header, the
implementation may pick one to use for the comparison, or treat the
situation as a failure of the comparison.

メッセージが複数 [CODE(822)[[[Return-Path]]]]
頭を持っている場合、実装は比較時にどれか1つを選んでも構いませんし、
比較失敗としても構いません。

>   The reason for not automatically sending an MDN if the comparison
fails or more than one address is specified is to reduce 
the [DEL(rfc3798)[possibilities for mail loops and use of MDNs]] [INS(rfc3798)[possibility of mail loops and of MDNs being used]] for mail bombing.

比較失敗時や複数の番地が指定された時に自動的に送信するべきではないのは、
メイルの循環や [[MDN]] が[[メイル爆弾]]に使われる危険性を減らすためです。

>   A message that contains a Disposition-Notification-To header SHOULD
also contain a Message-ID header as specified in [DEL(rfc3798)[RFC 822 [2] ]] [INS(rfc3798)[ [RFC-MSGFMT] ]].  This
will permit automatic correlation of MDNs with [INS(rfc3798)[their]] original
messages by user agents.

[CODE(822)[Disposition-Notification-To]] 頭を含むメッセージは、
[[RFC 2822]] で規定されている [CODE(822)[[[Message-ID]]]] 
頭も含むべきです。そうすれば[[利用者エージェント]]は [[MDN]]
と元のメッセージを自動的に関係づけられます。

> If [DEL(rfc3798)[it is desired to]] [INS(rfc3798)[the]] request [INS(rfc3798)[for]] message disposition notifications for some
recipients and not others [INS(rfc3798)[is desired]], two copies of the message
should be sent, one with a[DEL(rfc3798)[n]] Disposition-Notification-To header and one
without.  Many of the other headers of the message (e.g., To, [DEL(rfc3798)[cc]] [INS(rfc3798)[Cc]])
will be the same in both copies.  The recipients in the respective
message envelopes determine for whom message disposition
notifications are requested and for whom they are not.  If desired,
the Message-ID header may be the same in both copies of the message.
Note that there are other situations (e.g., [DEL(rfc3798)[bcc]] [INS(rfc3798)[Bcc]]) in which it is
necessary to send multiple copies of a message with slightly
different headers.  The combination of such situations and the need
to request MDNs for a subset of all recipients may result in more
than two copies of a message being sent, some with a 
Disposition-Notification-To header and some without.

受信者の一部にはメッセージ配置通知を要求し、他の受信者には要求したくない時は、
[CODE(822)[[[Disposition-Notification-To]]]] 頭があるものとないものの
2種類を用意して送信するべきです。メッセージの他の多くの頭 (例えば
[CODE(822)[[[To]]]] や [CODE(822)[[[Cc]]]] は両者共同じにします。
各メッセージの[[封筒]]にはそれぞれメッセージ配置通知を要求する[[受信者]]と要求しない受信者を指定します。
それが望ましければ両メッセージ共 [CODE(822)[[[Message-ID]]]] 
頭は同じにしても構いません。ちなみに、他にも頭が幾分異なるメッセージを複数送信するのが必要な状況があります
(例えば [CODE(822)[[[Bcc]]]] の時)。そうした状況と受信者の一部で [[MDN]] 
要求が必要な場合との組合せで [CODE(822)[[[Disposition-Notification-To]]]]
頭が含まれるものと含まれないものも入れて3種類以上のメッセージが必要となるかもしれません。

>    Messages posted to newsgroups SHOULD NOT have a 
Disposition-Notification-To header.

[[ニュース組]]に[[投函]]するメッセージは
[CODE(822)[[[Disposition-Notification-To]]]] 頭を持つ'''べきではありません'''。

* 2.2[INS(rfc3798)[.]]  The Disposition-Notification-Options Header
>   Future extensions to this specification may require that information
be supplied to the recipient's [INS(rfc3798)[M]]UA for additional control over how
and what MDNs are generated.  The Disposition-Notification-Options
header provides an extensible mechanism for such information.  The
syntax of this header[DEL(rfc3798)[, using the ABNF of RFC 822 [2],]]
is [INS(rfc3798)[as follows:]]

>
-      Disposition-Notification-Options =           "Disposition-Notification-Options" ":"           disposition-notification-parameters
>
-      disposition-notification-parameters = parameter *(";" parameter)
>
-     parameter = attribute "=" importance "," [DEL(rfc3798)[1#value]] [INS(rfc3798)[value *("," value)]]
>
-      importance = "required" / "optional"

[DEL(rfc3798)[
>   The definitions of attribute and value are as in the definition of
the Content-Type header in RFC 2045 [4].

[CODE(ABNF)[[[attribute]]]]  と [CODE(ABNF)[[[value]]]]
は [[RFC 2045]] の [CODE(MIME)[[[Content-Type]]]]
頭の定義によります。
]DEL]

>    An importance of "required" indicates that interpretation of the
parameter is necessary for proper generation of an MDN in response to
this request.  If a[INS(rfc 3798)[n M]]UA does not understand the meaning of the
parameter, it MUST NOT generate an MDN with any disposition type
other than "failed" in response to the request.  An importance of
"optional" indicates that a[INS(rfc3798)[n M]]UA that does not understand the meaning
of this parameter MAY generate an MDN in response anyway, ignoring
the value of the parameter.

重要度 [CODE(822)[[[required]]]] はこの要求に対する [[MDN]]
の適切な生成のためにその[[引数]]の解釈が必要であることを示します。
[[MUA]] がその引数を理解できない場合には、この要求に対して
[CODE(MDN)[[[failed]]]] 以外の配置型の [[MDN]] 応答を生成しては'''なりません'''。
重要度 [CODE(822)[[[optional]]]] はその引数を理解できない [[MUA]]
もその引数の値を無視して [[MDN]] 応答を生成して'''構わない'''ことを表します。

>    No parameters are defined in this specification.  Parameters may be
defined in the future by later revisions or extensions to this
specification.  Parameter attribute names beginning with "X-" will
never be defined as standard names; such names are reserved for
experimental use.  MDN parameter names not beginning with "X-" MUST
be registered with the Internet Assigned Numbers Authority (IANA) and
described in a standards-track RFC or an experimental RFC approved by
the IESG.  [INS(rfc3798)[(]]See Section 10 for a registration form.[INS(rfc3798)[)]]

この仕様では引数を定義しません。引数はこの仕様の将来の改訂や拡張で定義するかもしれません。
[CODE(822)[[[X-]]]] で始まる引数属性名は標準の名前としては決して定義せず、
実験用に予約します。 [CODE(822)[[[X-]]]] で始まらない [[MDN]]
引数名は [[IANA]] に登録すると共に [[IESG]] で承認された[[標準化過程]]
[[RFC]] か[[実験的]] [[RFC]] で説明しなければ'''なりません'''。

>    If a required parameter is not understood or contains some sort of
error, the receiving [INS(rfc3798)[M]]UA SHOULD issue an MDN with a disposition type
of "failed" (see Section 3.2.6)[INS(rfc3798)[,]] and include a Failure field (see
Section 3.2.7) that further describes the problem.  MDNs with the [DEL(rfc3798)[a]]
disposition type of "failed" and a "Failure" field MAY also be
generated when other types of errors are detected in the parameters
of the Disposition-Notification-Options header.

必須の引数が理解できなかったか何らかの[[誤り]]を含む場合、
[CODE(MDN)[[[failed]]]] 配置型で問題を説明した [CODE(MDN)[[[Failure]]]]
欄を含んだ [[MDN]] を受信した [[MUA]] は発行する'''べきです'''。
配置型が [CODE(MDN)[[[failed]]]] で [CODE(MDN)[[[Failure]]]] な [[MDN]]
は [CODE(822)[[[Disposition-Notification-Options]]]] 頭の引数で他の種類の誤りが検出された時にも生成して'''構いません'''。

>    However, an MDN with a disposition type of "failed" MUST NOT be
generated if the user has indicated a [DEL(rfc3798)[preferance]] [INS(rfc3798)[preference]] that MDNs are not to
be sent.  If user consent would be required for an MDN of some other
disposition type to be sent, user consent SHOULD also be obtained
before sending an MDN with a disposition type of "failed".

しかし、配置型 [CODE(MDN)[[[failed]]]] の [[MDN]] は[[利用者]]が [[MDN]]
を送信しないと設定している時には生成しては'''なりません'''。
何か他の配置型の [[MDN]] を送るために利用者の同意が必要なら、
利用者の同意も配置型 [CODE(MDN)[[[failed]]]] の [[MDN]]
を送信する前に得る'''べきです'''。

*2.3[INS(rfc3798)[.]]  The Original-Recipient Header
>   Since electronic mail addresses may be rewritten while the message is
in transit, it is useful for the original recipient address to be
made available by the delivering MTA.  The delivering MTA may be able
to obtain this information from the ORCPT parameter of the SMTP RCPT
TO command, as defined in [DEL(rfc3798)[RFC 1891 [8] ]] [INS(rfc3798)[ [RFC-SMTP] and [RFC-DSN-SMTP]]].

電子メイル番地は[[メッセージ]]の転送中に書き換えられるかもしれませんから、
[[配達]]する [[MTA]] が元の[[受信者]]の番地を利用可能にすると便利です。
配達 MTA はこの情報を [[SMTP]] [CODE[[[RCPT]] [[TO]]]] [[命令]]
の [CODE[[[ORCPT]]]] 引数から得ることができるかもしれません。

>  [INS(rfc3798)[ [RFC-DSN-SMTP] is amended as follows:]] If [DEL(rfc3798)[this]] [INS(rfc3798)[the ORCPT]] information is
available, the delivering MTA SHOULD insert an Original-Recipient
header at the beginning of the message (along with the Return-Path
header).  The delivering MTA MAY delete any other Original-Recipient
headers that occur in the message.  The syntax of this header[DEL(rfc3798)[, using the ABNF of RFC 822 [2],]] is as follows]][INS(rfc3798)[:]]

この [CODE[[[ORCPT]]]] 情報が利用可能名場合、配達 [[MTA]]
はメッセージのはじめに ([CODE(822)[[[Return-Path]]]]
頭と一緒に) [CODE(822)[[[Original-Recipient]]]]
頭を挿入する'''べきです'''。配達 MTA はメッセージにある他の
[CODE(822)[[[Original-Recipient]]]] 頭を削除して'''構いません'''。
この頭の構文は次の通りです。

>
-      original-recipient-header =
"Original-Recipient" ":" address-type ";" generic-address

>   The address-type and generic-address token are as [DEL(rfc3798)[as]] specified in the
description of the Original-Recipient field in section 3.2.3.

[CODE(822)[[[Original-Recipient]]]] 欄の字句 
[CODE(ABNF)[[[address-type]]]] と [CODE(ABNF)[[[generic-address]]]]
は3.2.3節にあります。

>   The purpose of carrying the original recipient information and
returning it in the MDN is to permit automatic correlation of MDNs
with the original message on a per-recipient basis.

元の受信者の情報を伝達してとそれを [[MDN]]
で返すのは、 [[MDN]] を元のメッセージと受信者毎に自動的に関係づけるためです。

*2.4[INS(rfc3798).]]  Use with the Message/Partial Content Type
>   The use of the headers Disposition-Notification-To, Disposition-
Notification-Options, and Original-Recipient with the MIME
[DEL(rfc3798)[Message/partial]] [INS(rfc3798)[message/partial]] content type ([DEL(rfc3798)[RFC 2046 [5] ]] [INS(rfc3798)[ [RFC-MIME-MEDIA] ]]) requires further
definition.

[[MIME]] [CODE(MIME)[[[message/partial]]]] [[内容型]]と
[CODE(822)[[[Disposition-Notification-To]]]],
[CODE(822)[[[Disposition-Notification-Options]]]],
[CODE(822)[[[Original-Recipient]]]] を併用するためには更に定義が必要です。

>   When a message is segmented into two or more message/partial
fragments, the three headers mentioned in the above paragraph SHOULD
be placed in the "inner" or "enclosed" message (using the terms 
of [DEL(rfc3798)[RFC 2046 [5] ]] [INS(rfc3798)[ [RFC-MIME-MEDIA] ]]).
These headers SHOULD NOT be used in the headers
of any of the fragments themselves.

メッセージが2つ以上の [CODE(MIME)[[[message/partial]]]]
素片に分割される時は、前段落の3つの頭を
([[RFC 2046]] の用語で言う) [Q[[[内側]]]]の ([Q[囲まれた]])
メッセージに入れる'''べきです'''。これらの頭は素片自体の頭に使う'''べきではありません'''。

>   When the multiple message/partial fragments are reassembled, the
following applies.  If these headers occur along with the other
headers of a message/partial fragment message, they pertain to an 
MDN [DEL(rfc3798)[to]] [INS(rfc3798)[that will]] be generated for the fragment.  If these headers occur in
the headers of the "inner" or "enclosed" message (using the terms 
of [DEL(rfc3798)[RFC 2046 [5] ]] [INS(rfc3798)[ [RFC-MIME-MEDIA] ]]), they pertain to an MDN to be generated for
the reassembled message.  Section 5.2.2.1 of [DEL(rfc3798)[RFC 2046 [5] ]] [INS(rfc3798)[ [RFC-MIME-MEDIA] ]]) is
amended to specify that, in addition to the headers specified there,
the three headers described in this specification are to be appended,
in order, to the headers of the reassembled message.  Any occur[INS(rfc3798)[r]]ences
of the three headers defined here in the headers of the initial
enclosing message must not be copied to the reassembled message.

複数の [CODE(MIME)[[[message/partial]]]] 素片を再結合する時は次の通りとします。
これらの頭が [CODE(MIME)[[[message/partial]]]]
素片メッセージの他の頭と一緒に出現したなら、その素片について [[MDN]]
を生成することになります。頭が ([[RFC 2045]] の用語で言う)
[Q[[[内側]]]]の ([Q[囲まれた]]) メッセージの頭として出現するなら、
再結合したメッセージについて [[MDN]] を生成することを表します。
[[RFC 2046]] の5.2.2.1節は、既に規定されている頭に加えてこの仕様で説明した
3つの頭も再結合メッセージの頭としてこの順で付加するよう改訂します。
ここで定義した3つの頭が最初の囲んでいるメッセージの頭に存在する時は再結合メッセージに複写してはなりません。

* 3.  Format of a Message Disposition Notification
>   A message disposition notification is a MIME message with a top-level
content-type of multipart/report (defined in [DEL(rfc3798)[RFC 1892 [7] ]] [INS(rfc3798)[ [RFC-REPORT] ]]). 
When [DEL(rfc3798)[a]] multipart/report content is used to transmit an MDN:

メッセージ配置通知は最上位[[内容型]]が [CODE(MIME)[[[multipart/report]]]]
の [[MIME]] [[メッセージ]]です。
[CODE(MIME)[[[multipart/report]]]] 内容が [[MDN]]
を転送するのに使われる時は、

>
-    (a)  The report-type parameter of the multipart/report content is
"disposition-notification".
-    (b)  The first component of the multipart/report contains a 
human-readable explanation of the MDN, as described in [DEL(rfc3798)[RFC 1892 [7] ]] [INS(rfc3798)[ [RFC-REPORT] ]]).
-    (c)  The second component of the multipart/report is of content-type
message/disposition-notification, described in section 3.1 of this document.
-    (d)  If the original message or a portion of the message is to be
returned to the sender, it appears as the third component of the
multipart/report.  The decision of whether or not to return the
message or part of the message is up to the [INS(rfc3798)[M]]UA generating the
MDN.  However, in the case of encrypted messages requesting
MDNs, encrypted message text MUST be returned, if it is returned
at all, only in its original encrypted form.

- [CODE(MIME)[[[multipart/report]]]] 内容の [CODE(MIME)[[[report-type]]]]
引数は [CODE(MIME)[[[disposition-notification]]]] です。
- [CODE(MIME)[[[multipart/report]]]] の最初の部分は [[MDN]]
の人間可読な説明を含みます。
- [CODE(MIME)[[[multipart/report]]]] の2番目の部分はこの文書の
3.1節で説明する[[内容型]] [CODE(MIME)[[[message/disposition-notification]]]]
のものです。
- 元のメッセージの一部または全部を[[送信者]]に返す時は
[CODE(MIME)[[[multipart/report]]]] の3番目の部分とします。
メッセージの一部または全部を返すかどうかの決定は [[MDN]]
を生成する [[MUA]] が行います。しかし、[[暗号化]]メッセージが [[MDN]]
を要求している場合、暗号化メッセージ文を全部返すのであれば元の暗号化形でのみ返さなければ'''なりません'''。

>    NOTE:  For message dispos[INS(rfc3798)[i]]tion notifications gatewayed from foreign
systems, the headers of the original message may not be
available.  In this case[INS(rfc3798)[,]] the third component of the MDN may be
omitted, or it may contain "simulated" [DEL(rfc3798)[RFC 822]] [INS(rfc3798)[ [RFC-MSGFMT] ]] headers that
contain equivalent information.  In particular, it is very
desirable to preserve the subject and date fields from the original message.

注意: 外部システムから[[関門]]を通じてやってくるメッセージ配置通知では元のメッセージの頭が利用できないかもしれません。
その場合、 [[MDN]] の3番目の部分は省略しても構いませんし、
等価な情報を含む[Q[仮想]]の [[RFC 2822]] 頭を含めても構いません。
特に主題欄や日付欄を元のメッセージから保存することが非常に望ましいと思われます。

>    The MDN MUST be addressed (in both the message header and the
transport envelope) to the address(es) from the 
Disposition-Notification-To header from the original message for which the MDN is
being generated.

[[MDN]] は [[MDN]] が生成される対象である元のメッセージの
[CODE(822)[[[Disposition-Notification-To]]]] 頭の
(単数または複数の) [[番地]]に
(メッセージの頭においても輸送[[封筒]]においても) 宛てなければ'''なりません'''。

>    The From field of the message header of the MDN MUST contain the
address of the person for whom the message disposition notification
is being issued.

[[MDN]] のメッセージ頭の [CODE(822)[[[From]]]] 欄はメッセージ配置通知を発行する人の番地を含まなければ'''なりません'''。

>    The envelope sender address (i.e., SMTP MAIL FROM) of the MDN MUST be
null (<>), specifying that no Delivery Status Notification messages
or other messages indicating successful or unsuccessful delivery are
to be sent in response to an MDN.

[[MDN]] の送信者番地 (すなわち [[SMTP]] [CODE[[[MAIL]] [[FROM]]]])
は空 ([CODE[[[<>]]]]) にして配送状態通知メッセージやその他の配送の成功・
不成功を知らせるメッセージが [[MDN]] に対する応答として送られないように指定しなければ'''なりません'''。

>    A message disposition notification MUST NOT itself request an MDN.
That is, it MUST NOT contain a Disposition-Notification-To header.

メッセージ配置通知自体は [[MDN]] を要求しては'''なりません'''。
つまり、 [[MDN]] は [CODE(822)[[[Disposition-Notification-To]]]] 
頭を含んでは''なりません'''。

>    The Message-ID header (if present) for an MDN MUST be different from
the Message-ID of the message for which the MDN is being issued.

[[MDN]] の [CODE(822)[[[Message-ID]]]] 頭は (あれば)
[[MDN]] を発行する対象のメッセージの [CODE(822)[[[Message-ID]]]]
とは異ならなければ'''なりません'''。

>    A particular MDN describes the disposition of exactly one message for
exactly one recipient.  Multiple MDNs may be generated as a result of
one message submission, one per recipient.  However, due to the
circumstances described in Section 2.1, MDNs may not be generated for
some recipients for which MDNs were requested.

特定の [[MDN]] は丁度一人の[[受信者]]の丁度一つのメッセージの配置を説明します。
一つのメッセージ[[提出]]の結果として受信者毎に一つずつであわせて複数の [[MDN]]
が生成されるかもしれません。しかし、2.1節で説明した状況により [[MDN]]
が要求された受信者について [[MDN]] が生成されないこともあります。

**3.1[INS(rfc3798)[.]]  The message/disposition-notification content-type
>   The message/disposition-notification content-type is defined as follows:

[CODE(MIME)[[[message/disposition-notification]]]]
内容型は次の通り定義します。

>
:      MIME type name:                message
:   MIME subtype name:   disposition-notification
:   Optional parameters: none
:      Encoding considerations:       "7bit" encoding is sufficient and
MUST be used to maintain readability when viewed by non-MIME mail readers.
:      Security considerations:       discussed in section 6 of this memo.

:MIME 型名:[CODE(MIME)[message]]
:MIME 亜型名:[CODE(MIME)[disposition-notification]]
:省略可能引数:なし
:符号化:[CODE(MIME)[[[7bit]]]] で十分であり、非 [[MIME]]
メイル読み器での表示時の可読性を維持するためにこれを使用しなければ'''なりません'''。
:安全性:このメモの6章で議論します。

>    The message/disposition-notification report type for use in the
multipart/report is "disposition-notification".

[CODE(MIME)[[[multipart/report]]]] で使用する
[CODE(MIME)[[[message/disposition-notification]]]]
報告型は [CODE(MIME)[[[disposition-notification]]]] です。

>    The body of a message/disposition-notification consists of one or
more "fields" formatted according to the ABNF 
of [DEL(rfc3798)[RFC 822]] [INS(rfc3798)[ [RFC-MSGFMT] ]] header
"fields" [DEL(rfc3798)[(see [2])]].  [DEL(rfc3798)[Using the ABNF of RFC 822, the]] [INS(rfc3798)[The]]
syntax of the message/disposition-notification content is as follows:

[CODE(MIME)[[[message/disposition-notification]]]]
の[[本体]]は [[RFC 2822]] の頭[Q[欄]]の
[[ABNF]] に従って書式付けした1つ以上の[Q[[[欄]]]]から成ります。
[CODE(MIME)[[[message/disposition-notification]]]] 内容の構文は次の通りです。

>
      disposition-notification-content = [ reporting-ua-field CRLF ]
           [ mdn-gateway-field CRLF ]
           [ original-recipient-field CRLF ]
           final-recipient-field CRLF
           [ original-message-id-field CRLF ]
           disposition-field CRLF
           *( failure-field CRLF )
           *( error-field CRLF )
           *( warning-field CRLF )
           *( extension-field CRLF )

***3.1.1[INS(rfc3798)[.]]  General conventions for fields
>
Since these fields are defined according to the rules 
of [DEL(rfc3798)[RFC 822 [2] ]] [INS(rfc3798)[ [RFC-MSGFMT] ]],
the same conventions for continuation lines and comments
apply. Notification fields may be continued onto multiple lines by
beginning each additional line with a SPACE or HTAB.  
Text [DEL(rfc3798)[which]] [INS(rfc3798)[that]] 
appears in parentheses is considered a comment and not part of the
contents of that notification field.  Field names are 
case-insensitive, so the names of notification fields may be spelled in
any combination of upper and lower case letters.  Comments in
notification fields may use the "encoded-word" construct defined 
in [DEL(rfc3798)[RFC 2047 [6] ]] [INS(rfc3798)[ [RFC-MIME-HEADER] ]].

欄は [[RFC 2822]] の規則に従って定義しますから、
[[継続行]]や[[注釈]]についても同じ規則を適用します。
通知欄は [CODE(ABNF)[[[SPACE]]]] や [CODE(ABNF)[[[HTAB]]]]
で始まる追加行を使って複数行に継続できます。
括弧内に表れる文章は[[注釈]]とし、
その通知欄の内容の一部とはしません。欄名は大文字・
小文字を区別しないので、大文字と小文字の任意の組合せで綴ることができます。
通知欄の注釈は [[RFC 2047]] で定義される [CODE(ABNF)[[[encoded-word]]]]
構造を使って構いません。

***3.1.2[INS(rfc3798)[.]]  "*-type" subfields
>    Several fields consist of a "-type" subfield, followed by a 
semi-colon, followed by "*text".  For these fields, the keyword used in
the address-type or MTA-type subfield indicates the expected format
of the address or MTA-name that follows.

幾つかの欄は [CODE[-type]] 部分欄とセミコロンと
[CODE(ABNF)[*text]] から成ります。そのような欄では
[CODE(ABNF)[address-type]] 部分欄または [CODE(ABNF)[MTA-type]]
部分欄で使う[[鍵語]]がその後の番地や [[MTA]]
名で期待される書式を示します。

>   The "-type" subfields are defined as follows:

[CODE[-type]] 部分欄は次のように定義します。

>    (a)  An "address-type" specifies the format of a mailbox address.
For example, Internet Mail addresses use the "rfc822" address-type.

[CODE[address-type]] はメイル箱番地の書式を指定します。
例えばインターネット・メイル番地は [SAMP[[[rfc822]]]]
[CODE(ABNF)[[[address-type]]]] を使います。

>          address-type = atom

>   (b)  An "MTA-name-type" specifies the format of a mail transfer
agent name.  For example, for an SMTP server on an Internet
host, the MTA name is the domain name of that host, and the
"dns" MTA-name-type is used.

[CODE(ABNF)[MTA-name-type]] はメイル転送エージェント名の書式を指定します。
例えばインターネットの[[ホスト]]の SMTP]] 鯖では [[MTA]]
名はそのホストの[[ドメイン名]]で、 [CODE[[[dns]]]]
[CODE(ABNF)[MTA-name-type]] を使います。

>          mta-name-type = atom

>   Values for address-type and mta-name-type are case-insensitive.
Thus[INS(rfc3798)[,]] address-type values of "RFC822" and "rfc822" are equivalent.

[CODE(ABNF)[address-type]] と [CODE(ABNF)[mta-name-type]]
の値は大文字・小文字を区別しません。ですから、
[CODE(ABNF)[address-type]] 値 [SAMP[RFC822]] と
[SAMP[rfc822]] は等価です。

>   The Internet Assigned Numbers Authority (IANA) [DEL(rfc3798)[will]] maintain[INS(rfc3798)[s]] a registry
of address-type and mta-name-type values, along with
descriptions of the meanings of each, or a reference to [DEL(rfc3798)[a]] one or more
specifications that provide such descriptions.  (The "rfc822"
address-type is defined in [DEL(rfc3798)[RFC 1891 [8] ]] [INS(rfc3798)[ [RFC-DSN-SMTP] ]].)  Registration forms for
address-type and mta-name-type appear in [DEL(rfc3798)[RFC 1894 [9] ]] [INS(rfc3798)[ [RFC-DSN-FORMAT] ]].

[[IANA]] は [CODE(ABNF)[address-type]] 値と [CODE(ABNF)[mta-name-type]]
値とそれぞれの意味の説明またはその説明を提供する
1つ以上の仕様書への参照を添えた登録簿を管理します。
([CODE[[[rfc822]]]] [CODE(ABNF)[address-type]] は [[RFC 1891]]
で定義されています。) [CODE(ABNF)[address-type]] と
[CODE(ABNF)[mta-name-type]] の登録フォームは [[RFC 1894]] にあります。

[DEL(rfc3798)[
>   IANA will not accept registrations for any address-type name that
begins with "X-".  These type names are reserved for experimental use.

[[IANA]] は [CODE[[[X-]]]] で始まる [CODE(ABNF)[address-type]]
名の登録を受け付けません。この型名は実験用に予約します。
]DEL]

*3.1.3 Lexical tokens imported from RFC 822
[DEL(rfc3798)[
>   The following lexical tokens, defined in RFC 822 [2], are used in the
ABNF grammar for MDNs:  atom, CRLF, mailbox, msg-id, text.

[[RFC 822]] で定義されている字句 [CODE(ABNF)[[[atom]]]], [CODE(ABNF)[[[CRLF]]]],
[CODE(ABNF)[[[mailbox]]]], [CODE(ABNF)[[[msg-id]]]],
[CODE(ABNF)[[[text]]]] を [[MDN]] の [[ABNF]]
文法で使います。
]DEL]

**3.2[INS(rfc3798)[.]]  Message/disposition-notification Fields
***3.2.1[INS(rfc3798)[.]]  The Reporting-UA field
>
-      reporting-ua-field = "Reporting-UA" ":" ua-name [ ";" ua-product ]
>
-      ua-name = *text
>
-      ua-product = *text

>    The Reporting-UA field is defined as follows:

[CODE(MDN)[[[Reporting-UA]]]] 欄は次のように定義します。

>   A[INS(rfc3798)[n]] MDN describes the disposition of a message after it has been
delivered to a recipient.  In all cases, the Reporting-UA is the [INS(rfc3798)[M]]UA
that performed the disposition described in the MDN.  This field is
optional, but recommended.  For Internet Mail user agents, it is
recommended that this field contain both[INS(rfc3798)[:]] the DNS name of the
particular instance of the [INS(rfc3798)[M]]UA that generated the MDN[INS(rfc3798)[,]] and the name
of the product.  For example,

[[MDN]] は[[メッセージ]]が[[受信者]]に[[配送]]された後にその[[配置]]を説明します。
すべての場合において [CODE(MDN)[[[Reporting-UA]]]] は [[MDN]]
に説明されている配置を行った [[MUA]] とします。この欄は省略可能ですが、
記述することを推奨します。インターネット・メイル[[利用者エージェント]]では、
この欄に [[MDN]] を生成した [[MUA]] の特定の[[実現値]]の [[DNS]]
名とその製品名の両方を含めることを推奨します。

>
-    [DEL(rfc3798)[Reporting-UA:  rogers-mac.dcrt.nih.gov; Foomail 97.1]]
-    [INS(rfc3798)[Reporting-UA:  pc.example.com; Foomail 97.1]]

>   If the reporting [INS(rfc3798)[M]]UA consists of more than one component (e.g., a
base program and plug-ins), this may be indicated by including a list
of product names.

報告する [[MUA]] が複数の部品 (例えば基底プログラムと[[プラグイン]])
で構成されている時は、製品名の並びを含めることによりこれを示して構いません。

***3.2.2[DEL(rfc3798)[.]]  The MDN-Gateway field
>   The MDN-Gateway field indicates the name of the gateway or MTA that
translated a foreign (non-Internet) message disposition notification
into this MDN.  This field MUST appear in any MDN [DEL(rfc3798)[which]] [INS(rfc3798)[that]] was
translated by a gateway from a foreign system into MDN format, and
MUST NOT appear otherwise.

[CODE(MDN)[[[MDN-Gateway]]]] 欄は外部 (非インターネット)
メッセージ配置通知からこの [[MDN]] へ翻訳した[[関門]]または [[MTA]]
の名前を示します。この欄は外部システムから [[MDN]]
の書式に翻訳された [[MDN]] には必ず出現しなければ'''なりません'''。また、
その他の [[MDN]] には出現しては'''なりません'''。

>
-         mdn-gateway-field = "MDN-Gateway" ":" mta-name-type ";" mta-name
>
-         mta-name = *text

>    For gateways into Internet Mail, the MTA-name-type will normally be
"smtp", and the mta-name will be the Internet domain name of the gateway.

インターネット・メイルへの[[関門]]では [CODE(ABNF)[MTA-name-type]]
は通常 [CODE[[[smtp]]]] であり、 [CODE(ABNF)[mta-name]]
は[[関門]]のインターネット・ドメイン名です。

***3.2.3[INS(rfc3798)[.]]  Original-Recipient field
>   The Original-Recipient field indicates the original recipient address
as specified by the sender of the message for which the MDN is being
issued.  For Internet Mail messages[INS(rfc3798)[,]] the value of the 
Original-Recipient field is obtained from the Original-Recipient
header from the message for which the MDN is being generated.  If
there is no Original-Recipient header in the message, then the
Original-Recipient field MUST be omitted, unless the same information
is reliably available some other way.  If there is an
Original-Recipient header in the original message (or original recipient
information is reliably available some other way), then the
Original-Recipient field must be supplied.  If there is more than one
Original-Recipient header in the message, the [INS(rfc3798)[M]]UA may choose the one
to use[INS(rfc3798)[,]] or act as if no Original-Recipient header is present.

[CODE(MDN)[[[Original-Recipient]]]] 欄は [[MDN]]
が発行された対象の[[メッセージ]]の[[送信者]]が指定した元の[[受信者]]の番地を示します。
インターネット・メイルのメッセージでは、
[CODE(MDN)[[[Original-Recipient]]]] 欄の値は [[MDN]]
が生成される対象の[[メッセージ]]の [CODE(822)[[[Original-Recipient]]]]
頭から得ます。その[[メッセージ]]に [CODE(822)[[[Original-Recipient]]]]
頭がなければ、同じ情報が他の信頼できる方法で得られる場合を除き、
[CODE(MDN)[[[Original-Recipient]]]] 欄は省略しなければ'''なりません'''。
元の[[メッセージ]]に [CODE(822)[[[Original-Recipient]]]] 頭があれば
(または何か別の信頼できる方法で元の[[受信者]]の情報が得られれば)、
[CODE(MDN)[[[Original-Recipient]]]] 欄を供給しなければなりません。
元の[[メッセージ]]に複数 [CODE(822)[[[Original-Recipient]]]]
頭があれば、 [[MUA]] は一つ選んで使っても構いませんし、
[CODE(822)[[[Original-Recipient]]]] 頭が存在しないように動作しても構いません。

>
-      original-recipient-field = "Original-Recipient" ":" address-type ";" generic-address
>
-      generic-address = *text

>   The address-type field indicates the type of the original recipient
address.  If the message originated within the Internet, the
address-type field [DEL(rfc3798)[field]] will normally be "rfc822", and the address will be
according to the syntax specified in [DEL(rfc3798)[RFC 822 [2] ]] [INS(rfc3798)[ [RFC-MSGFMT] ]].  The value
"unknown" should be used if the Reporting [INS(rfc3798)[M]]UA cannot determine the
type of the original recipient address from the message envelope.

[CODE(ABNF)[address-type]] 欄は元の[[受信者]]の[[番地]]の型を示します。
メッセージが[[インターネット]]内で作成されたものなら、
[CODE(ABNF)[address-type]] 欄は通常 [CODE[[[rfc822]]]]
となり、[[番地]]は [[RFC 2822]] で規定された構文に従います。報告する [[MUA]]
が元の[[受信者]]の[[番地]]の型を[[メッセージ]]の[[封筒]]から決定できなければ、
値 [CODE[[[unknown]]]] を使うべきです。

>    This address is the same as that provided by the sender and can be
used to automatically correlate MDN reports with original messages on
a per recipient basis.

この[[番地]]は[[送信者]]が提供したものと同じであり、
[[MDN]] の報告と元の[[メッセージ]]を受信者毎に自動的に関係付けるために使うことができます。

*3.2.4[INS(rfc3798)[.]]  Final-Recipient field
>   The Final-Recipient field indicates the recipient for which the MDN
is being issued.  This field MUST be present.

[CODE(MDN)[[[Final-Recipient]]]] 欄は [[MDN]]
を発行する対象の[[受信者]]を示します。この欄は存在しなければ'''なりません'''。

>    The syntax of the field is as follows:

この欄の構文は次の通りです。

>      final-recipient-field =           "Final-Recipient" ":" address-type ";" generic-address

>    The generic-address subfield of the Final-Recipient field MUST
contain the mailbox address of the recipient (from the From header of
the MDN) as it was when the MDN was generated by the [INS(rfc3798)[M]]UA.

[CODE(MDN)[[[Final-Recipient]]]] 欄の [CODE(ABNF)[generic-address]]
部分欄は [[MUA]] が [[MDN]] を生成した時の[[受信者]]の[[メイル箱]]の[[番地]]を
([[MDN]] の [CODE(822)[[[From]]]] 欄から) 含めなければ'''なりません'''。

>    The Final-Recipient address may differ from the address originally
provided by the sender, because it may have been transformed during
forwarding and gatewaying into a[DEL(rfc3798)[n]] totally unrecognizable mess.
However, in the absence of the optional Original-Recipient field, the
Final-Recipient field and any returned content may be the only
information available with which to correlate the MDN with a
particular message recipient.

メッセージはまったく認識できないところを[[転送]]されたり[[関門]]を通過したりして転送されてきたかもしれませんから、
[CODE(MDN)[[[Final-Recipient]]]] 番地は元々送信者が指定した番地とは違っているかもしれません。
しかし、省略可能な [CODE(MDN)[[[Original-Recipient]]]]
欄が存在しない時には [CODE(MDN)[[[Final-Recipient]]]]
欄と返される内容だけが [[MDN]] と特定のメッセージ[[受信者]]を関係付けるために使える情報となります。

>    The address-type subfield indicates the type of address expected by
the reporting MTA in that context.  Recipient addresses obtained via
SMTP will normally be of address-type "rfc822".

[CODE(ABNF)[address-type]] 部分欄は報告する [[MTA]]
がその文脈で期待する[[番地]]の型を示します。
[[SMTP]] で得られる[[受信者]]の[[番地]]の [CODE(ABNF)[[[address-type]]]]
は通常 [CODE[[[rfc822]]]] です。

>    Since mailbox addresses (including those used in the Internet) may be
case sensitive, the case of alphabetic characters in the address MUST
be preserved.

メイル箱番地は (インターネットで使われているものも含めて)
大文字・小文字を区別を行うので、番地の大文字・
小文字は保存しなければ'''なりません'''。

***3.2.5[INS(rfc3798)[.]]  Original-Message-ID field
>   The Original-Message-ID field indicates the message-ID of the message
for which the MDN is being issued.  It is obtained from the 
Message-ID header of the message for which the MDN is issued.  This field
MUST be present if the original message contained a Message-ID
header.  The syntax of the field is [INS(rfc3798)[as follows:]]

[CODE(MDN)[[[Original-Message-ID]]]] 欄は [[MDN]]
が発行される対象の[[メッセージ]]のメッセージ識別子を示します。
メッセージ識別子は [[MDN]] が発行される対象の[[メッセージ]]の
[CODE(822)[[[Message-ID]]]] 頭から得ます。この欄は元の[[メッセージ]]が
[CODE(822)[[[Message-ID]]]] を含む時には存在しなければ'''なりません'''。
この欄の構文は次の通りです。

>
-     original-message-id-field = "Original-Message-ID" ":" msg-id

>   The msg-id token is as specified 
in [DEL(rfc3798)[RFC 822 [2] ]] [INS(rfc3798)[ [RFC-MSGFMT] ]].

字句 [CODE(ABNF)[[[msg-id]]]] は [[RFC 2822]]
で定義されています。

***3.2.6[INS(rfc3798)[.]]  Disposition field
>    The Disposition field indicates the action performed by the
Reporting-[INS(rfc3798)[M]]UA on behalf of the user.  This field MUST be present.

[CODE(MDN)[[[Disposition]]]] 欄は [CODE(MDN)[[[Reporting-MUA]]]]
が[[利用者]]に代わって行った動作を示します。
この欄は存在しなければ'''なりません'''。

>    The syntax for the Disposition field is:

[CODE(MDN)[[[Disposition]]]] 欄の構文は次の通りです。

>
-
[PRE(ABNF)[
    disposition-field =
              "Disposition" ":" disposition-mode ";"
                         disposition-type
              [ "/" disposition-modifier
              *( "," disposition-modifier ) ]
]PRE]
> 
-      disposition-mode = action-mode "/" sending-mode
> 
-      action-mode = "manual-action" / "automatic-action"
> 
-      sending-mode = "MDN-sent-manually" / "MDN-sent-automatically"
> 
-
[PRE(ABNF)[
      disposition-type = "displayed"
                      [DEL(rfc3798)[/ "dispatched"]]
                      [DEL(rfc3798)[/ "processed"]]
                       / "deleted"
                      [DEL(rfc3798)[/ "denied"]]
                      [DEL(rfc3798)[/ "failed"]]
]PRE]
>
-
[PRE(ABNF)[
     [DEL(rfc3798)[disposition-modifier = ( "error" / "warning" )]]
                          [DEL(rfc3798)[/ ( "superseded" / "expired" /]]
                              [DEL(rfc3798)["mailbox-terminated" )]]
     [INS(rfc3798)[disposition-modifier = "error"]]
                           / disposition-modifier-extension
]PRE]
> 
-      disposition-modifier-extension = atom

>  The disposition-mode, disposition-type[INS(rfc3798)[,]] and disposition-modifier may
be spelled in any combination of upper and lower case characters.

[CODE(ABNF)[disposition-mode]], [CODE(ABNF)[disposition-type]],
[CODE(ABNF)[disposition-modifier]] は大文字・
小文字の任意の組合せで綴って構いません。

****3.2.6.1[INS(rfc3798)[.]]  Disposition modes
>    The following disposition modes are defined:

次の配置モードを定義します。

>    "manual-action"        The disposition described by the disposition
type was a result of an
explicit instruction by the user rather than some sort of automatically performed action.

:[CODE(MDN)[[[manual-action]]]]:配置型で説明された配置は何らかの自動実行行為ではなく、
[[利用者]]の明示的な指示による結果です。

>    "automatic-action"     The disposition described by the disposition
type was a result of an automatic action,
rather than an explicit instruction by the
user for this message.

:[CODE(MDN)[[[automatic-action]]]]:配置型で説明された配置はこのメッセージに対する[[利用者]]の明示的な指示による結果ではなく、
自動的な動作の結果です。

>   "Manual-action" and "automatic-action" are mutually exclusive.  One
or the other [DEL(rfc3798)[must]] [INS(rfc3798)[MUST]] be specified.

[CODE(MDN)[[[manual-action]]]] と [CODE(MDN)[[[automatic-action]]]]
は相互に排他的です。どちらか1つだけを指定しなければ'''なりません'''。

>    "MDN-sent-manually"    The user explicitly gave permission for this
particular MDN to be sent.

:[CODE(MDN)[[[MDN-sent-manually]]]]:[[利用者]]が明示的にこの [[MDN]]
を送信することを許可しました。

>    "MDN-sent-automatically"
The MDN was sent because the MUA had
previously been configured to do so automatically.

:[CODE(MDN)[[[MDN-sent-automatically]]]]:
[[MDN]] は以前に [[MUA]] が自動的に送信するように設定されているので
送信しました。

>   "MDN-sent-manually" and "MDN-sent-automatically" are mutually
exclusive.  One or the other [DEL(rfc3798)[must]] [INS(rfc3798)[MUST]] be specified.

[CODE(MDN)[[[MDN-sent-manually]]]] と [CODE(MDN)[[[MDN-sent-automatically]]]]
は相互に排他的です。どちらか1つだけを指定しなければ'''なりません'''。

****3.2.6.2[INS(rfc3798)[.]]  Disposition types
>    The following disposition-types are defined:

次の [CODE(ABNF)[disposition-type]] を定義します。

>    "displayed"            The message has been displayed by the [INS(rfc3798)[M]]UA
to someone reading the recipient's mailbox.
There is no guarantee that the content has been read or understood.

:[CODE(MDN)[[[displayed]]]]:[[メッセージ]]は [[MUA]]
から[[受信者]]の[[メイル箱]]を読む誰かに表示されました。
[[内容]]が読まれ理解されたという保証はありません。

[DEL(rfc3798)[
>   "dispatched"   The message has been sent somewhere in some manner
(e.g., printed, faxed, forwarded) without necessarily having been previously
displayed to the user.  The user may or may not see the message later.

:[CODE(MDN)[[[dispatched]]]]:[[メッセージ]]は必ずしも[[利用者]]に以前に[[表示]]されずに何らかの形でどこかに送信
(例えば[[印刷]]、[[FAX]]、[[転送]]) されました。
[[利用者]]は後から[[メッセージ]]を見たかもしれませんし、
見ていないかもしれません。

>  "processed"    The message has been processed in some manner (i.e.,
by some sort of rules or server) without
being displayed to the user.  The user may
or may not see the message later, or there
may not even be a human user associated with the mailbox.

:[CODE(MDN)[[[processed]]]]:[[メッセージ]]は[[利用者]]に[[表示]]されることなく何らかの形で
(何らかの規則や[[鯖]]により) 処理されました。[[利用者]]は後から[[メッセージ]]を見たかもしれませんし、
見ていないかもしれません。あるいはその[[メイル箱]]に関連付けられた人間の利用者は存在すらしていないかもしれません。
]DEL]

>    "deleted"              The message has been deleted.  The
recipient may or may not have seen the
message.  The recipient might "undelete"
the message at a later time and read the message.

:[CODE(MDN)[[[delete]]]]:[[メッセージ]]は[[削除]]されました。
[[受信者]]は[[メッセージ]]を見たかもしれませんし、
見ていないかもしれません。[[受信者]]は後から[[メッセージ]]の削除を取消して内容を読むかもしれません。

[DEL(rfc3798)[
>   "denied"       The recipient does not wish the sender to be informed
of the message's disposition.  A UA may
also siliently ignore message disposition requests in this situation.

:[CODE(MDN)[[[denied]]]]:[[受信者]]は[[メッセージ]]の[[配置]]を[[送信者]]に通知したくないと思っています。
[[MUA]] はこの状況下では黙ってメッセージ配置通知要求を無視しても構いません。

>   "failed"       A failure occurred that prevented the proper
generation of an MDN.  More information
about the cause of the failure may be contained in a Failure field.  The
"failed" disposition type is not to be used for the situation in which there is
is some problem in processing the message
other than interpreting the request for an
MDN.  The "processed" or other disposition type with appropriate disposition
modifiers is to be used in such situations.

:[CODE(MDN)[[[failed]]]]:失敗があって [[MDN]]
を適切に生成できませんでした。失敗の原因についての詳しい情報が
[CODE(MDN)[[[Failure]]]] 欄に含まれているかもしれません。
[CODE(MDN)[[[failed]]]] 配置型は [[MDN]] の[[要求]]の解釈以外で[[メッセージ]]の処理に問題が発生した場合に対しては使いません。
そのような状況においては [CODE(MDN)[[[processed]]]]
などの配置型を適切な配置修飾子と一緒に使います。
]DEL]

****3.2.6.3[INS(rfc3798)[.]]  Disposition modifiers

[DEL(rfc3798)[
>   The following disposition modifiers are defined:

次の配置修飾子を定義します。

>   "error"                            An error of some sort occurred
that prevented successful processing of the message.
Further information is contained in an Error field.

:[CODE(MDN)[[[error]]]]:[[メッセージ]]の処理を正常に行えないような何らかの[[誤り]]が発生しました。
更なる情報が [CODE(MDN)[[[Error]]]] 欄に含まれています。

>   "warning"                          The message was successfully
processed but some sort of exceptional condition occurred.
Further information is contained in a Warning field.

:[CODE(MDN)[[[warning]]]]:[[メッセージ]]は正常に処理されましたが、
何らかの例外的状況が発生しました。更なる情報が
[CODE(MDN)[[[Warning]]]] 欄に含まれています。

>   "superseded"                       The message has been
automatically rendered obsolete by another message received.  The
recipient may still access and read the message later.

:[CODE(MDN)[[[superseded]]]]:[[メッセージ]]は他の受信した[[メッセージ]]により自動的に[[廃止]]とされました。
[[受信者]]はそれでも後からその[[メッセージ]]にアクセスして読むことができるかもしれません。

>   "expired"                          
The message has reached its expiration date and has been
automatically removed from the recipient's mailbox.

:[CODE(MDN)[[[expired]]]]:[[メッセージ]]は[[満期]]の日付に到達し、
[[受信者]]の[[メイル箱]]から自動的に削除されました。

>   "mailbox-terminated"               The recipient's mailbox has been
terminated and all message in it automatically removed.

:[CODE(MDN)[[[mailbox-terminated]]]]:[[受信者]]の[[メイル箱]]は終了し、
すべての[[メッセージ]]が自動的に削除されました。

< "Obsoleted", "expired", and
"terminated" are to be used with the "deleted" disposition type and
the "autoaction" and "autosent" disposition modifiers.

[CODE(MDN)[[[obsoleted]]]], [CODE(MDN)[[[expired]]]],
[CODE(MDN)[[[terminated]]]] は配置型 [CODE(MDN)[[[deleted]]]]
および配置修飾子の [CODE(MDN)[[[autoaction]]]] や [CODE(MDN)[[[autosent]]]]
と併用します。
]DEL]

[INS(rfc3798)[
>   Only the extension disposition modifiers is defined:

拡張配置修飾子だけを定義します。
]INS]

>    disposition-modifier-extension [DEL(rfc3798)[Additional disposition]] [INS(rfc3798)[Disposition]] modifiers may be defined
in the future by later revisions
or extensions to this specification.
Disposition value names beginning with "X-"
will never be defined as standard values;
such names are reserved for experimental
use.  MDN disposition value names NOT
beginning with "X-" MUST be registered with
the Internet Assigned Numbers Authority
(IANA) and described in a standards-track
RFC or an experimental RFC approved by the
IESG.  [INS(rfc3798)[(]]See Section 10 for a registration
form.[INS(rfc3798)[)]]  MDNs with disposition modifier
names not understood by the receiving [INS(rfc3798)[M]]UA
MAY be silently ignored or placed in the user's mailbox without special
inter[DEL(rfc3798)[-]]pretation.  They MUST not cause any
error message to be sent to the sender of the MDN.

[[配置修飾子]]はこの仕様の将来の改訂版や拡張で定義されるかもしれません。
名前が [CODE(MDN)[[[X-]]]] で始まる配置値は標準の値として定義されることはなく、
実験用に予約します。 [CODE(MDN)[[[X-]]]] で始まら'''ない''' [[MDN]]
配置値は [[IANA]] に登録すると共に [[IESG]] で承認された[[標準化過程]] [[RFC]]
または[[実験的]] [[RFC]] で説明しなければ'''なりません'''。受信した [[MUA]]
が理解できない[[配置修飾子]]名を使った [[MDN]] は特別な解釈を行わずに無視したり[[利用者]]の[[メイル箱]]に入れたりして'''構いません'''。
しかし [[MDN]] の[[送信者]]に誤りメッセージを送信しては'''なりません'''。

>   If a[INS(rfc3798)[n M]]UA developer does not wish to register the meanings of such
disposition modifier extensions, "X-" modifiers may be used for this
purpose.  To avoid name collisions, the name of the [INS(rfc3798)[M]]UA
implementation should follow the "X-", (e.g., "X-Foomail-[DEL(rfc3798)[fratzed]]").

[[MUA]] 開発者が[[配置修飾子]]拡張の意味を登録したくない時は、
[CODE(MDN)[[[X-]]]] 修飾子を使って構いません。名前の衝突を防ぐために [[MUA]]
実装の名前を [CODE(MDN)[[[X-]]]] の後に
(例えば [SAMP(MDN)[X-Foomail-]] のように) 付けるべきです。

>   It is not required that a[INS(rfc3798)[n M]]UA be able to generate all of the
possible values of the Disposition field.

[[MUA]] が [CODE(MDN)[[[Disposition]]]] 欄の可能なすべての値を生成できる必要はありません。

>   [DEL(rfc3798)[One and only one MDN may be issued on behalf of each particular recipient by their user agent.]] [INS(rfc3798)[A user agent MUST NOT issue more than one MDN on behalf of each particular recipient.]]
That is, once an MDN has been issued on behalf
of a recipient, no further MDNs may be issued on behalf of that
recipient, even if another disposition is performed on the message.
However, if a message is forwarded, a "dispatched" MDN may be[DEL(rfc3798)[en]] issued
for the recipient doing the forwarding and the recipient
of the forwarded message may also cause an MDN to be generated.

[[利用者エージェント]]は[[受信者]]それぞれに対して複数の MDN]]
を発行しては'''なりません'''。つまり、一度ある[[受信者]]に代わって [[MDN]]
を発行したら、[[メッセージ]]に他の配置を行ったとしても更に [[MDN]]
を発行してはいけません。ただし、[[メッセージ]]が[[転送]]される時は[[転送]]する[[受信者]]に代わって
[CODE(MDN)[[[dispatched]]]] [[MDN]] を発行しても構いませんし、
[[転送]][[メッセージ]]の[[受信者]]も [[MDN]]
を生成させて構いません。

***3.2.7[INS(rfc3798)[.]]  Failure, Error[INS(rfc3798)[,]] and Warning fields
>   The Failure, Error[INS(rfc3798)[,]] and Warning fields are used to supply additional
information in the form of text messages when the "failure"
disposition type, "error" disposition modifier, and/or the "warning"
disposition modif[INS(rfc3798)[i]]er appear.  The syntax is [INS(rfc3798)[as follows:]]

欄 [CODE(MDN)[[[Failure]]]], [CODE(MDN)[[[Error]]]], [CODE(MDN)[[[Wawrning]]]]
は [CODE(MDN)[[[failure]]]] [[配置型]]、
[CODE(MDN)[[[error]]]] [[配置修飾子]][[及び/又は]]
[CODE(MDN)[[[warning]]]] [[配置修飾子]]が出現する時に追加情報を文章で供給するために使います。
構文は次の通りです。

>
-      failure-field = "Failure" ":" *text
>
-      error-field = "Error" ":" *text
> 
-      warning-field = "Warning" ":" *text

**3.3[INS(rfc3798)[.]]  Extension-fields
>   Additional MDN fields may be defined in the future by later revisions
or extensions to this specification.  Extension-field names beginning
with "X-" will never be defined as standard fields; such names are
reserved for experimental use.  MDN field names NOT beginning with
"X-" MUST be registered with the Internet Assigned Numbers Authority
(IANA) and described in a standards-track RFC or an experimental RFC
approved by the IESG.  [INS(rfc3798)[(]]See Section 10 for a registration form.[INS(rfc3798)[)]]

この仕様の将来の改訂版や拡張は追加の [[MDN]] [[欄]]を定義するかもしれません。
[CODE(MDN)[[[X-]]]] で始まる拡張欄名は標準の欄として定義することはなく、
実験用に予約します。 [CODE(MDN)[[[X-]]]] で始まら'''ない''' [[MDN]]
欄名は [[IANA]] に登録すると共に [[IESG]] で承認された[[標準化過程]] [[RFC]]
または[[実験的]] [[RFC]] で説明しなければ'''なりません'''。

>   [DEL(rfc3798)[Extension MDN fields]] [INS(rfc3798)[MDN Extension-fields]] 
may be defined for the following reasons:

[[MDN]] 拡張欄は次のような理由で定義されるかもしれません。

>   (a)  To allow additional information from foreign disposition reports
to be tunneled through Internet MDNs.  The names of such MDN
fields should begin with an indication of the foreign
environment name (e.g.[INS(rfc3798)[,]] X400-Physical-Forwarding-Address).

外部配置報告からの情報を[[インターネット]] [[MDN]]
を通じて[[トンネル]]化できるようにするため。この場合 [[MDN]]
欄の名前は外部環境名で始めるべきです (例:
[SAMP(MDN)[X400-Physical-Forwarding-Address]])。

>   (b)  To allow transmission of diagnostic information [DEL(rfc3798)[which]] [INS(rfc3798)[that]] is specific
to a particular [INS(rfc3798)[mail]] user agent ([INS(rfc3798)[M]]UA).  The names of such MDN
fields should begin with an indication of the [INS(rfc3798)[M]]UA 
implementation [DEL(rfc3798)[which]] [INS(rfc3798)[that]] produced the MDN.  (e.g. Foomail-information).

特定の [[MUA]] 実装特有の診断情報の転送ができるようにするため。
この場合 [[MDN]] 欄の名前は [[MUA]] 実装の名前で始めるべきです (例:
[SAMP(MDN)[Foomail-information]])。

[INS[
訳注: このような目的の欄が [[IESG]] の評価を通過できるとは到底思えませんが...
]INS]

>    If an application developer does not wish to register the meanings of
such extension fields, "X-" fields may be used for this purpose.  To
avoid name collisions, the name of the application implementation
should follow the "X-", (e.g.[INS(rfc3798)[,]] "X-Foomail-Log-ID" or "X-[INS(rfc3798)[Foomail-]]EDI-info").

応用開発者がこのような拡張欄の意味を登録したくない時は、
[CODE(MDN)[[[X-]]]] 欄を使って構いません。名前の衝突を防ぐため、
応用実装の名前を [CODE(MDN)[[[X-]]]] の後に付けるべきです
(例えば [SAMP(MDN)[X-Foomail-Log-ID]] や [SAMP(MDN)[X-Foomail-EDI-Info]])。

* 4.  Timeline of events
>   The following timeline shows when various events in the processing of
a message and generation of MDNs take place:

次の時間表は[[メッセージ]]の処理と [[MDN]] の生成において色々な[[事象]]が起こる時期を示しています。

>   -- User composes message
>   -- User tells [INS(rfc3798)[M]]UA to send message
>   -- [INS(rfc3798)[M]]UA passes message to MTA (original recipient information passed along)
>   -- MTA sends message to next MTA
>   -- Final MTA receives message
>   -- Final MTA delivers message to [INS(rfc3798)[M]]UA (possibly generating a DSN)
>   -- [INS(rfc3798)[M]]UA performs automatic processing and generates corresponding MDNs
("dispatched", "processed", "deleted", "denied"[INS(rfc3798)[,]] or "failed"
disposition type with "automatic-action" and "MDN-sent-automatically" disposition modes)
>   -- [INS(rfc3798)[M]]UA displays list of messages to user
>   -- User selects a message and requests that some action be performed on it. 
>   -- [INS(rfc3798)[M]]UA performs requested action and, with user's permission,
sends [INS(rfc3798)[an]] appropriate MDN ("displayed", "dispatched", "processed",
"deleted", "denied"[INS(rfc3798)[,]] or "failed" disposition type, with 
"manual-action" and "MDN-sent-manually" or "MDN-sent-automatically"
disposition mode).
> -- User possibly performs other actions on message, but no
further MDNs are generated.

= [[利用者]]が[[メッセージ]]を作成
=[[利用者]]が [[MUA]] に[[メッセージ]]を[[送信]]するよう指示
=[[MUA]] が[[メッセージ]]を [[MTA]] に渡す
(元の[[受信者]]の情報が一緒に渡される)
=[[MTA]] が次の [[MTA]] に[[メッセージ]]を[[送信]]
=最後の [{MTA]] が[[メッセージ]]を[[受信]]
=最後の [[MTA]] が [[MUA]] に[[メッセージ]]を[[配送]]
([[DSN]] を生成する場合も)
=[[MUA]] が自動処理を実行して対応する [[MDN]] を生成
([[配置型]]は [CODE(MDN)[[[dispatched]]]], [CODE(MDN)[[[processed]]]],
[CODE(MDN)[[[deleted]]]], [CODE(MDN)[[[denied]]]], [CODE(MDN)[[[failed]]]] で、
[[配置モード]]は [CODE(MDN)[[[automatic-action]]]] と
[CODE(MDN)[[[MDN-sent-automatically]]]])
=[[MUA]] が[[メッセージ]]の一覧を[[利用者]]に[[表示]]
=[[利用者]]が[[メッセージ]]を選択して、
それに対して何らかの動作を実行
=[[MUA]] が要求された動作を実行して適切な [[MDN]] を生成
([[配置型]]は [CODE(MDN)[[[displayed]]]],
[CODE(MDN)[[[dispatched]]]], [CODE(MDN)[[[processed]]]],
[CODE(MDN)[[[deleted]]]], [CODE(MDN)[[[denied]]]], [CODE(MDN)[[[failed]]]] で、
[[配置モード]]は [CODE(MDN)[[[manual-action]]]] と
[CODE(MDN)[[[MDN-sent-manually]]]] または
[CODE(MDN)[[[MDN-sent-automatically]]]])
=[[利用者]]がその[[メッセージ]]に対して更に他の動作を実行するかもしれないが、
もう [[MDN]] は生成しない

* 5.  Conformance and Usage Requirements
>   A[INS(rfc3798)[n M]]UA or gateway conforms to this specification if it generates MDNs
according to the protocol defined in this memo.  It is not necessary
to be able to generate all of the possible values of the Disposition field.

[[MUA]] や[[関門]]は、このメモで定義した[[プロトコル]]に従って [[MDN]]
を生成する時、この仕様に[[適合]]します。 [CODE(MDN)[[[Disposition]]]]
欄が取り得る全ての値を生成できる必要はありません。

>   [INS(rfc3798)[M]]UAs and gateways MUST NOT generate the Original-Recipient field of
an MDN unless the mail protocols provide the address originally
specified by the sender at the time of submission.  Ordinary SMTP
does not make that guarantee, but the SMTP extension defined 
in [DEL(rfc3798)[RFC 1891 [8] ]] [INS(rfc3798)[ [RFC-DSN-SMTP] ]] permits such information to be carried in the envelope
if it is available.  The Original-Recipient header defined in this
document provides a way for the MTA to pass the original recipient
address to the [INS(rfc3798)[M]]UA.

[[MUA]] と[[関門]]は[[送信者]]が[[提出]]時に元々指定した[[番地]]をメイル・プロトコルが提供していない限り
[[MDN]] の [CODE(MDN)[[[Original-Recipient]]]] 欄を生成しては'''なりません'''。
普通 [[SMTP]] はこれを保証しませんが、 [[RFC 1891]]
で定義された [[SMTP]] 
の拡張を使えばこの情報が利用可能な時[[封筒]]で伝達できます。
この文書で定義された [CODE(822)[[[Original-Recipient]]]]
頭は [[MTA]] が元の受信者の番地を [[MUA]] に渡す手段を提供しています。

>    Each sender-specified recipient address may result in more than one
MDN.  If an MDN is requested for a recipient that is forwarded to
multiple recipients of an "alias" (as defined 
in [DEL(rfc3798)[ RFC 1891 [8] ]] [INS(rfc3798)[ [RFC-DSN-SMTP] ]],
section 6.2.7.3), each of the recipients may issue an MDN.

送信者が指定した受信者の番地それぞれについて複数の [[MDN]]
が発行されることがあります。ある[[受信者]]に [[MDN]]
が要求され、それが[Q[[[別名]]]]の複数の[[受信者]]に[[転送]]されると、
受信者のそれぞれが [[MDN]] を発行するかもしれません。

>   Successful distribution of a message to a mailing list exploder
SHOULD be considered [INS(rfc3798)[the]] final disposition of the message.  A mailing
list exploder [DEL(rfc3798)[may]] [INS(rfc3798)[MAY]] issue an MDN with a disposition type of "processed"
and disposition modes of "automatic-action" and 
"MDN-sent-automatically" indicating that the message has been forwarded to the
list.  In this case, the request for MDNs is not [DEL(rfc3798)[propogated]] [INS(rfc3798)[propagated]] to the
members of the list.

[[メイリング・リスト]]配送器へ[[メッセージ]]の配布が成功したら、
それをもって[[メッセージ]]の最終的な配置とみなす'''べきです'''。
[[メイリング・リスト]]配送器は[[配送型]]が [CODE(MDN)[[[processed]]]]
で[[は移送モード]]が [CODE(MDN)[[[automatic-action]]]] と
[CODE(MDN)[[[MDN-sent-automatically]]]] であって[[メッセージ]]が[[メイリング・リスト]]に[[転送]]されたことを示す
[[MDN]] を発行して'''構いません'''。この場合、 [[MDN]]
の要求は[[メイリング・リスト]]の参加者には伝播しません。

>   Alterna[INS(rfc3798)[t]]ively, the mailing list exploder [DEL(rfc3798)[may]] [INS(rfc3798)[MAY]] issue no MDN 
and [DEL(rfc3798)[propogate]] [INS(rfc3798)[propagate]] the request for MDNs to all members of the list.  The
latter behavior is not recommended for any but small, closely knit
lists, as it might cause large numbers of MDNs to be generated and
may cause confidential subscribers to the list to be revealed. [DEL(rfc3798)[It is also permissible for the mailing list exploder to ]] [INS(rfc3798)[The mailing list exploder MAY also ]]
direct MDNs to itself, correlate them,
and produce a report to the original sender of the message.

代わりに[[メイリング・リスト]]配送器は [[MDN]]
を発行せずに [[MDN]] の要求を[[メイリング・リスト]]の参加者に伝播しても'''構いません'''。
後者の動作は大量の [[MDN]] が生成されてしまいますし、
[[メイリング・リスト]]の参加者が分かってしまいますから、
小さな親しい参加者の[[メイリング・リスト]]以外では推奨しません。
[[メイリング・リスト]]配送器は [[MDN]]
を自身に向けて送らせて、元の[[メッセージ]]の[[送信者]]への報告を作成しても'''構いません'''。

>    This specification places no restrictions on the processing of MDNs
received by user agents or mailing lists.

この仕様は[[利用者エージェント]]や[[メイリング・リスト]]が受信した
[[MDN]] の処理については何の制限も行いません。

* 6.  Security Considerations
>    The following security considerations apply when using MDNs:

[[MDN]] を使う時は次の安全上の考慮が必要です。

**6.1[INS(rfc3798)[.]]  Forgery
>   MDNs may be forged as easily as ordinary Internet electronic mail.
User agents and automatic mail handling facilities (such as mail
distribution list exploders) that wish to make automatic use of MDNs
should take appropriate precautions to minimize the potential damage
from denial-of-service attacks.

>    Security threats related to forged MDNs include the sending of:
 
    (a)  A falsified disposition notification when the indicated
-        disposition of the message has not actually ocurred,
+        disposition of the message has not actually occurred,
 
    (b)  Unsolicited MDNs
 
-6.2 Confidentiality

-   Another dimension of security is confidentiality.  There may be cases
+   Another dimension of security is privacy.  There may be cases
in which a message recipient does not wish the disposition of
-   messages addressed to him to be known or is concerned that the
+   messages addressed to him to be known, or is concerned that the sending of
-   sending of MDNs may reveal other confidential information (e.g., when
-   the message was read).  In this situation, it is acceptable for the
-   UA to issue "denied" MDNs or to silently ignore requests for MDNs.
+   MDNs may reveal other sensitive information (e.g., when the message
+   was read).  In this situation, it is acceptable for the MUA to issue
+   "denied" MDNs or to silently ignore requests for MDNs.
 
    If the Disposition-Notification-To header is passed on unmodified
    when a message is distributed to the subscribers of a mailing list,
    the subscribers to the list may be revealed to the sender of the
    original message by the generation of MDNs.
 
    Headers of the original message returned in part 3 of the
    multipart/report could reveal confidential information about host
    names and/or network topology inside a firewall.
 
    An unencrypted MDN could reveal confidential information about an
    encrypted message, especially if all or part of the original message
    is returned in part 3 of the multipart/report.  Encrypted MDNs are
    not defined in this specification.
 
-   In general, any optional MDN field may be omitted if the Reporting UA
-   site or user determines that inclusion of the field would impose too
-   great a compromise of site confidentiality.  The need for such
+   In general, any optional MDN field may be omitted if the Reporting
+   MUA site or user determines that inclusion of the field would impose
+   too great a compromise of site confidentiality.  The need for such
    confidentiality must be balanced against the utility of the omitted
    information in MDNs.
 
-6.3 Non-Repudiation
 
-   Within the framework of today's Internet Mail, the MDNs defined in
-   this document provide valuable information to the mail user; however,
-   MDNs can not be relied upon as a guarantee that a message was or was
-   not not seen by the recipient.  Even if MDNs are not actively forged,
-   they may be lost in transit.  The MDN issuing mechanism may be
-   bypassed in some manner by the recipient.
+   In some cases, someone with access to the message stream may use the
+   MDN request mechanism to monitor the mail reading habits of a target.
+   If the target is known to generate MDN reports, they could add a
+   disposition-notification-to field containing the envelope from
+   address along with a source route.  The source route is ignored in
+   the comparison so the addresses will always match.  But if the source
+   route is honored when the notification is sent, it could direct the
+   message to some other destination.  This risk can be minimized by not
+   sending MDN's automatically.
+
+6.3.  Non-Repudiation
+
+   MDNs do not provide non-repudiation with proof of delivery.  Within
+   the framework of today's Internet Mail, the MDNs defined in this
+   document provide valuable information to the mail user; however, MDNs
+   cannot be relied upon as a guarantee that a message was or was not
+   seen by the recipient.  Even if MDNs are not actively forged, they
+   may be lost in transit.  The recipient may bypass the MDN issuing
+   mechanism in some manner.
+
+   One possible solution for this purpose can be found in RFC 2634
+   [SEC-SERVICES].
+
+6.4.  Mail Bombing
+
+   The MDN request mechanism introduces an additional way of mailbombing
+   a mailbox.  The MDN request notification provides an address to which
+   MDN's should be sent.  It is possible for an attacking agent to send
+   a potentially large set of messages to otherwise unsuspecting third
+   party recipients with a false "disposition-notification-to:" address.
+   Automatic, or simplistic processing of such requests would result in
+   a flood of MDN notifications to the target of the attack.  Such an
+   attack could overrun the capacity of the targeted mailbox and deny
+   service.
+
+   For that reason, MDN's SHOULD NOT be sent automatically where the
+   "disposition-notification-to:" address is different from the envelope
+   MAIL FROM address.  See section 2.1 for further discussion.
 
* 7.  Collected Grammar
 
-   NOTE:  The following lexical tokens are defined in RFC 822:  atom,
-   CRLF, mailbox, msg-id, text.  The definitions of attribute and value
-   are as in the definition of the Content-Type header in RFC 2045 [4].
+   NOTE:  The following lexical tokens are defined in [RFC-MSGFMT]:
+   atom, CRLF, mailbox, msg-id, text.  The definitions of attribute and
+   value are as in the definition of the Content-Type header in [RFC-
+   MIME-BODY].

>   Message headers:
 
-   mdn-request-header = "Disposition-Notification-To" ":" 1#mailbox
 
-   Disposition-Notification-Options =
-        "Disposition-Notification-Options" ":"
-        disposition-notification-parameters
 
-   disposition-notification-parameters = parameter *(";" parameter)
+  mdn-request-header =
+     "Disposition-Notification-To" ":"
+            mailbox *("," mailbox)
+
+  Disposition-Notification-Options =
+            "Disposition-Notification-Options" ":"
+            disposition-notification-parameters
+
+  disposition-notification-parameters =
+            parameter *(";" parameter)
 
-   parameter = attribute "=" importance "," 1#value
+  parameter = attribute "=" importance "," value *("," value)
 
    importance = "required" / "optional"
 
    original-recipient-header =
         "Original-Recipient" ":" address-type ";" generic-address

    Report content:
 
  disposition-notification-content =
            [ reporting-ua-field CRLF ]
        [ mdn-gateway-field CRLF ]
        [ original-recipient-field CRLF ]
        final-recipient-field CRLF
        [ original-message-id-field CRLF ]
        disposition-field CRLF
        *( failure-field CRLF )
        *( error-field CRLF )
        *( warning-field CRLF )
        *( extension-field CRLF )
 
    address-type = atom
 
    mta-name-type = atom

  reporting-ua-field = "Reporting-UA" ":" ua-name [ ";" ua-product ]

    ua-name = *text
 
    ua-product = *text
 
    mdn-gateway-field = "MDN-Gateway" ":" mta-name-type ";" mta-name
 
    mta-name = *text
 
-   original-recipient-field =
-        "Original-Recipient" ":" address-type ";" generic-address
+  original-recipient-field
+            = "Original-Recipient" ":" address-type ";"
+            generic-address

  generic-address = *text

  final-recipient-field =
            "Final-Recipient" ":" address-type ";" generic-address

-   disposition-field = "Disposition" ":" disposition-mode ";"
-                       disposition-type
-                       [ '/' disposition-modifier
-                         *( "," dispostion-modifier ) ]
+  disposition-field =
+            "Disposition" ":" disposition-mode ";"
+            disposition-type
+            [ "/" disposition-modifier
+            *( "," disposition-modifier ) ]
 
    disposition-mode = action-mode "/" sending-mode
 
    action-mode = "manual-action" / "automatic-action"
 
    sending-mode = "MDN-sent-manually" / "MDN-sent-automatically"
 
    disposition-type = "displayed"
-                    / "dispatched"
-                    / "processed"
                     / "deleted"
-                    / "denied"
-                    / "failed"
 
-   disposition-modifier = ( "error" / "warning" )
-                        / ( "superseded" / "expired" /
-                            "mailbox-terminated" )
-                        / disposition-modifier-extension
+  disposition-modifier =  "error" / disposition-modifier-extension
 
    disposition-modifier-extension = atom
 
    original-message-id-field = "Original-Message-ID" ":" msg-id
 
    failure-field = "Failure" ":" *text
 
    error-field = "Error" ":" *text
 
    warning-field = "Warning" ":" *text
 
    extension-field = extension-field-name ":" *text
 
    extension-field-name = atom
 
* 8.  Guidelines for Gatewaying MDNs
 
    NOTE:  This section provides non-binding recommendations for the
    construction of mail gateways that wish to provide semi-transparent
    disposition notifications between the Internet and another electronic
    mail system.  Specific MDN gateway requirements for a particular pair
    of mail systems may be defined by other documents.
 
-8.1 Gatewaying from other mail systems to MDNs
+8.1.  Gatewaying from other mail systems to MDNs
 
-   A mail gateway may issue an MDN to convey the contents of a "foreign"
-   disposition notification over Internet Mail.  When there are
-   appropriate mappings from the foreign notification elements to MDN
+   A mail gateway may issue an MDN to convey the contents of a "foreign"
+   disposition notification over Internet Mail.  When there are
+   appropriate mappings from the foreign notification elements to MDN
    fields, the information may be transmitted in those MDN fields.
    Additional information (such as might be needed to tunnel the foreign
    notification through the Internet) may be defined in extension MDN
    fields.  (Such fields should be given names that identify the foreign
-   mail protocol, e.g. X400-* for X.400 protocol elements)
+   mail protocol, e.g., X400-* for X.400 protocol elements).
 
    The gateway must attempt to supply reasonable values for the
    Reporting-UA, Final-Recipient, and Disposition fields.  These will
    normally be obtained by translating the values from the foreign
    notification into their Internet-style equivalents.  However, some
    loss of information is to be expected.
 
-   The sender-specified recipient address, and the original message-id,
+   The sender-specified recipient address and the original message-id,
    if present in the foreign notification, should be preserved in the
    Original-Recipient and Original-Message-ID fields.
 
    The gateway should also attempt to preserve the "final" recipient
    address from the foreign system.  Whenever possible, foreign protocol
    elements should be encoded as meaningful printable ASCII strings.
 
    For MDNs produced from foreign disposition notifications, the name of
    the gateway MUST appear in the MDN-Gateway field of the MDN.
 
-8.2 Gatewaying from MDNs to other mail systems
+8.2.  Gatewaying from MDNs to other mail systems
 
    It may be possible to gateway MDNs from the Internet into a foreign
    mail system.  The primary purpose of such gatewaying is to convey
    disposition information in a form that is usable by the destination
    system.  A secondary purpose is to allow "tunneling" of MDNs through
-   foreign mail systems, in case the MDN may be gatewayed back into the
+   foreign mail systems in case the MDN may be gatewayed back into the
    Internet.
 
    In general, the recipient of the MDN (i.e., the sender of the
    original message) will want to know, for each recipient:  the closest
    available approximation to the original recipient address, and the
    disposition (displayed, printed, etc.).
 
    If possible, the gateway should attempt to preserve the Original-
-   Recipient address and Original-Message-ID (if present), in the
+   Recipient address and Original-Message-ID (if present) in the
    resulting foreign disposition report.
 
-   If it is possible to tunnel an MDN through the destination
-   environment, the gateway specification may define a means of
-   preserving the MDN information in the disposition reports used by
-   that environment.
+   If it is possible to tunnel an MDN through the destination
+   environment, the gateway specification may define a means of
+   preserving the MDN information in the disposition reports used by
+   that environment.
+
+8.3.  Gatewaying of MDN-requests to other mail systems
+
+   By use of the separate disposition-notification-to request header,
+   this specification offers a richer functionality than most, if not
+   all, other email systems.  In most other email systems, the
+   notification recipient is identical to the message sender as
+   indicated in the "from" address.  There are two interesting cases
+   when gatewaying into such systems:
+
+   1) If the address in the disposition-notification-to header is
+      identical to the address in the SMTP "MAIL FROM", the expected
+      behavior will result, even if the disposition-notification-to
+      information is lost.  Systems should propagate the MDN request.
+
+   2) If the address in the disposition-notification-to header is
+      different from the address in the SMTP "MAIL FROM", gatewaying
+      into a foreign system without a separate notification address will
+      result in unintended behavior.  This is especially important when
+      the message arrives via a mailing list expansion software that may
+      specifically replace the SMTP "MAIL FROM" address with an
+      alternate address.  In such cases, the MDN request should not be
+      gatewayed and should be silently dropped.  This is consistent with
+      other forms of non-support for MDN.
 
* 9.  Example
 
    NOTE:  This example is provided as illustration only, and is not
    considered part of the MDN protocol specification.  If the example
    conflicts with the protocol definition above, the example is wrong.
 
    Likewise, the use of *-type subfield names or extension fields in
    this example is not to be construed as a definition for those type
    names or extension fields.
 
-9.1 This is an MDN issued after a message has been displayed to the user
+   This is an MDN issued after a message has been displayed to the user
    of an Internet Mail user agent.
 
    Date: Wed, 20 Sep 1995 00:19:00 (EDT) -0400
-   From: Joe Recipient <Joe_Recipient@mega.edu>
+   From: Joe Recipient <Joe_Recipient@example.com>
-   Message-Id: <199509200019.12345@mega.edu>
+   Message-Id: <199509200019.12345@example.com>
    Subject: Disposition notification
-   To: Jane Sender <Jane_Sender@huge.com>
+   To: Jane Sender <Jane_Sender@example.org>
    MIME-Version: 1.0
    Content-Type: multipart/report; report-type=disposition-notification;
-         boundary="RAA14128.773615765/mega.edu"
+      boundary="RAA14128.773615765/example.com"
 
-   --RAA14128.773615765/mega.edu
+   --RAA14128.773615765/example.com
 
    The message sent on 1995 Sep 19 at 13:30:00 (EDT) -0400 to Joe
-   Recipient <Joe_Recipient@mega.edu> with subject "First draft of
+   Recipient <Joe_Recipient@example.com> with subject "First draft of
    report" has been displayed.  This is no guarantee that the message
    has been read or understood.
 
-   --RAA14128.773615765/mega.edu
+   --RAA14128.773615765/example.com
    content-type: message/disposition-notification
 
-   Reporting-UA: joes-pc.cs.mega.edu; Foomail 97.1
-   Original-Recipient: rfc822;Joe_Recipient@mega.edu
-   Final-Recipient: rfc822;Joe_Recipient@mega.edu
-   Original-Message-ID: <199509192301.23456@huge.com>
+   Reporting-UA: joes-pc.cs.example.com; Foomail 97.1
+   Original-Recipient: rfc822;Joe_Recipient@example.com
+   Final-Recipient: rfc822;Joe_Recipient@example.com
+   Original-Message-ID: <199509192301.23456@example.org>
    Disposition: manual-action/MDN-sent-manually; displayed
 
-   --RAA14128.773615765/mega.edu
+   --RAA14128.773615765/example.com
    content-type: message/rfc822
 
-   [original message goes here]
+   [original message optionally goes here]
-
-   --RAA14128.773615765/mega.edu--
+   --RAA14128.773615765/example.com--

+10.  IANA Considerations
-10.  IANA Registration Forms

+   This document specifies three types of parameters that must be
+   registered with the Internet Assigned Numbers Authority (IANA).
 
    The forms below are for use when registering a new parameter name for
    the Disposition-Notification-Options header, a new disposition
    modifier name, or a new MDN extension field.  Each piece of
    information required by a registration form may be satisfied either
    by providing the information on the form itself, or by including a
    reference to a published, publicly available specification that
    includes the necessary information.  IANA MAY reject registrations
-   because of incomplete registration forms, imprecise specifications,
+   because of incomplete registration forms or incomplete
-   or inappropriate names.
+   specifications.
 
-   To register, complete the applicable form below and send it via
+   To register, complete the following applicable form and send it via
    electronic mail to <IANA@IANA.ORG>.
 
-10.1 IANA registration form for Disposition-Notification-Options header
-   parameter names
+10.1.  Disposition-Notification-Options header parameter names
 
    A registration for a Disposition-Notification-Options header
    parameter name MUST include the following information:
 
    (a) The proposed parameter name.
 
    (b) The syntax for parameter values, specified using BNF, ABNF,
    regular expressions, or other non-ambiguous language.

>    (c) If parameter values are not composed entirely of graphic
characters from the US-ASCII repertoire, a specification for how
they are to be encoded as graphic US-ASCII characters in a
Disposition-Notification-Options header.

>   (d)  A reference to a standards track RFC or experimental RFC
approved by the IESG that describes the semantics of the parameter values.

-10.2 IANA registration form for disposition modifer names
+10.2.  Disposition modifier names
+
-   A registration for a disposition-modifier name MUST include
+   A registration for a disposition-modifier name (used in the
+   Disposition field of a message/disposition-notification) MUST include
the following information:

>   (a)  The proposed disposition-modifier name.
 
-   (b) A reference to a standards track RFC or experimental RFC approved
-   by the IESG that describes the semantics of the disposition modifier.
+   (b)  A reference to a standards track RFC or experimental RFC
+        approved by the IESG that describes the semantics of the
+        disposition modifier.
 
-10.3 IANA registration form for MDN extension field names
+10.3.  MDN extension field names

>   A registration for an MDN extension field name MUST include the
following information:

>   (a)  The proposed extension field name.

-   (b) The syntax for extension values, specified using BNF, ABNF,
-   regular expressions, or other non-ambiguous language.
+   (b)  The syntax for extension values, specified using BNF, ABNF,
+        regular expressions, or other non-ambiguous language.
 
-   (c) If extension field values are not composed entirely of graphic
-   characters from the US-ASCII repertoire, a specification for how they
-   are to be encoded as graphic US-ASCII characters in a Disposition-
-   Notification-Options header.
+   (c)  If extension-field values are not composed entirely of graphic
+        characters from the US-ASCII repertoire, a specification for how
+        they are to be encoded as graphic US-ASCII characters in a
+        Disposition-Notification-Options header.
 
-   (d) A reference to a standards track RFC or experimental RFC approved
-   by the IESG that describes the semantics of the extension field.
+   (d)  A reference to a standards track RFC or experimental RFC
+        approved by the IESG that describes the semantics of the
+        extension field.

* 11.  Acknowledgments

+   This document is an updated version of the original document written
+   by Roger Fajman.  His contributions to the definition of Message
+   Disposition Notifications are greatly appreciated.
+
-   This document is based on the Delivery Status Notifications document,
+   RFC 2298 was based on the Delivery Status Notifications document
-   RFC 1894 [9], by Keith Moore and Greg Vaudreuil.  Contributions
+   [RFC-DSN-FORMAT] by Keith Moore and Greg Vaudreuil.  Contributions
were made by members of the IETF Receipt Working Group, including
-   Harald Alverstrand, Ian Bell, Urs Eppenberger, Claus Andri Faerber,
+   Harald Alvestrand, Ian Bell, Urs Eppenberger, Claus Andri Faerber,
Ned Freed, Jim Galvin, Carl Hage, Mike Lake, Keith Moore, Paul
-   Overell, Pete Resnick, Chuck Shih.
+   Overell, Pete Resnick, and Chuck Shih.

* 12.  References

+12.1.  Normative References

-   [1]   Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC 821,
-         August 1982.
+   [RFC-SMTP]        Klensin, J., Ed., "Simple Mail Transfer Protocol",
+                     RFC 2821, April 2001.
 
-   [2]   Crocker, D., "Standard for the Format of ARPA Internet Text
-         Messages", STD 11, RFC 822, August 1982.
+   [RFC-MSGFMT]      Resnick, P., Ed., "Internet Message Format", RFC
+                     2822, April 2001.
 
-   [3]   Braden, R. (ed.), "Requirements for Internet Hosts -
-         Application and Support", STD 3, RFC 1123, October 1989.
 
-   [4]   Freed, N., and N. Borenstein, "Multipurpose Internet Mail
-         Extensions (MIME) Part One:  Format of Internet Message
-         Bodies", RFC 2045, November 1996.
+   [RFC-MIME-BODY]   Freed, N. and N. Borenstein, "Multipurpose Internet
+                     Mail Extensions (MIME) Part One: Format of Internet
+                     Message Bodies", RFC 2045, November 1996.
 
-   [5]   Freed, N., and N. Borenstein, "Multipurpose Internet Mail
-         Extensions (MIME) Part Two:  Media Types", RFC 2046, November
-         1996.
+   [RFC-MIME-MEDIA]  Freed, N. and N. Borenstein, "Multipurpose Internet
+                     Mail Extensions (MIME) Part Two: Media Types", RFC
+                     2046, November 1996.
 
-   [6]   Moore, K., "Multipurpose Internet Mail Extensions (MIME) Part
-         Three:  Message Header Extensions for Non-Ascii Text", RFC
-         2047, November 1996.
+   [RFC-MIME-HEADER] Moore, K., "MIME (Multipurpose Internet Mail
+                     Extensions) Part Three: Message Header Extensions
+                     for Non-ASCII Text", RFC 2047, November 1996.
 
-   [7]   Vaudreuil, G., "The Multipart/Report Content Type for the
-         Reporting of Mail System Administrative Messages", RFC 1892,
-         January 1996.
+   [RFC-REPORT]      Vaudreuil, G., "The Multipart/Report Content Type
+                     for the Reporting of Mail System Administrative
+                     Messages", RFC 3462, January 2003.
 
-   [8]   Moore, K., "SMTP Service Extension for Delivery Status
-         Notifications", RFC 1891, January 1996.
+   [RFC-DSN-SMTP]    Moore, K., "Simple Mail Transfer Protocol (SMTP)
+                     Service Extension for Delivery Status
+                     Notifications", RFC 3461, January 2003.
 
-   [9]   Moore, K., and G. Vaudreuil, "An Extensible Format for
-         Delivery Status Notifications, RFC 1894, January 1996. 
+   [RFC-DSN-FORMAT]  Moore, K., and G. Vaudreuil, "An Extensible Format
+                     for Delivery Status Notifications (DSNs)", RFC
+                     3464, January 2003.
+
-   [10]  Bradner, S., "Key Words for Use in RFCs to Indicate
+
+   [RFC-KEYWORDS]    Bradner, S., "Key Words for Use in RFCs to Indicate
          Requirement Levels", BCP 14, RFC 2119, March 1997.

+12.2.  Informative References
+
+   [SEC-SERVICES]    Hoffman, P., Ed., "Enhanced Security Services for
+                     S/MIME", RFC 2634, June 1999.

+Appendix A - Changes from RFC 2298
+
+   The document has new editors.
+
+   The dispositions "denied", and "failed" were removed from the
+   document reflecting the lack of implementation or usage at this time.
+
+   The disposition modifiers "warning", "superseded", "expired",
+   "mailbox-terminated" have not seen actual implementation.  They have
+   been deleted from this document.  The extension modifier, as of yet
+   unused, has been retained for future extension.
+
+   General editorial cleanups include spelling, grammar, and consistency
+   in usage of terms.
+
+   The document has modified BNF for disposition notification options to
+   eliminate the need for dummy values where not otherwise needed.

-13.  Author's Address
+Authors' Addresses

-   Roger Fajman
-   National Institutes of Health
-   Building 12A, Room 3063
-   12 South Drive MSC 5659
-   Bethesda, Maryland 20892-5659
-   USA
 
-   EMail:  raf@cu.nih.gov
-   Phone:  +1 301 402 4265
-   Fax:    +1 301 480 6241

+   Tony Hansen
+   AT&T Laboratories
+   Middletown, NJ 07748
+   USA
+   Voice: +1-732-420-8934
+   EMail: tony+rfc3798@maillennium.att.com
+
+   Gregory M. Vaudreuil
+   Lucent Technologies
+   7291 Williamson Rd
+   Dallas, TX 75214
+   USA
+   Voice: +1 214 823 9325
+   EMail: GregV@ieee.org

-14.  Full Copyright Statement
 
-   Copyright (C) The Internet Society (1998).  All Rights Reserved.
 
-   This document and translations of it may be copied and furnished to
-   others, and derivative works that comment on or otherwise explain it
-   or assist in its implementation may be prepared, copied, published
-   and distributed, in whole or in part, without restriction of any
-   kind, provided that the above copyright notice and this paragraph are
-   included on all such copies and derivative works.  However, this
-   document itself may not be modified in any way, such as by removing
-   the copyright notice or references to the Internet Society or other
-   Internet organizations, except as needed for the purpose of
-   developing Internet standards in which case the procedures for
-   copyrights defined in the Internet Standards process must be
-   followed, or as required to translate it into languages other than
-   English.
 
-   The limited permissions granted above are perpetual and will not be
-   revoked by the Internet Society or its successors or assigns.
 
-   This document and the information contained herein is provided on an
-   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
-   TASK FORCE DISCLAIMS 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.
 
+Full Copyright Statement
 
+   Copyright (C) The Internet Society (2004).  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.
 
+   This document and the information contained herein are provided on an
+   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+   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.
 
+Intellectual Property
 
+   The IETF takes no position regarding the validity or scope of any
+   Intellectual Property Rights or other rights that might be claimed to
+   pertain to the implementation or use of the technology described in
+   this document or the extent to which any license under such rights
+   might or might not be available; nor does it represent that it has
+   made any independent effort to identify any such rights.  Information
+   on the procedures with respect to rights in RFC documents can be
+   found in BCP 78 and BCP 79.
 
+   Copies of IPR disclosures made to the IETF Secretariat and any
+   assurances of licenses to be made available, or the result of an
+   attempt made to obtain a general license or permission for the use of
+   such proprietary rights by implementers or users of this
+   specification can be obtained from the IETF on-line IPR repository at
+   http://www.ietf.org/ipr.
 
+   The IETF invites any interested party to bring to its attention any
+   copyrights, patents or patent applications, or other proprietary
+   rights that may cover technology that may be required to implement
+   this standard.  Please address the information to the IETF at ietf-
+   ipr@ietf.org.
 
+Acknowledgement
 
+   Funding for the RFC Editor function is currently provided by the
+   Internet Society.
 
* memo