Network Working Group Greg Vaudreuil
Internet Draft Octel Network Services
Expires in six months Glenn Parsons
Obsoletes: RFC 1911 Nortel Technology
September 9, 1996
Voice Profile for Internet Mail - version 2
<draft-ema-vpim-01.txt>
Status of this Memo
This document is an Internet Draft. Internet Drafts are working
documents of the Internet Engineering Task Force (IETF), its Areas,
and its Working Groups. Note that other groups may also distribute
working documents as Internet Drafts.
Internet Drafts are valid for a maximum of six months and may be
updated, replaced, or obsoleted by other documents at any time. It is
inappropriate to use Internet Drafts as reference material or to cite
them other than as a "work in progress".
To learn the current status of any Internet-Draft, please check the
``1id-abstracts.txt'' listing contained in the Internet-Drafts Shadow
Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe),
munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or
ftp.isi.edu (US West Coast).
Overview
This document profiles Internet mail for voice messaging. It
obsoletes RFC 1911 which describes version 1 of the profile. A list
of changes from that document are noted in Appedix F. As well,
Appendix G lists the open issues with this version of VPIM.
Please send comments on this document to the EMA VPIM Work Group
mailing list: <vpim-l@ema.org>
Working Group Summary
This profile was not reviewed by an active IETF working group.
However, it has been reviewed by the VPIM Work Group of the Electronic
Messaging Association (EMA). This work group, which has
representatives from most major voice mail vendors, has held an
interoperability demonstration between voice messaging vendors and
received comments from traditional messaging vendors.
Internet Draft VPIM v2 September 9, 1996
Table of Contents
1. ABSTRACT 4
2. SCOPE 5
2.1 Voice Messaging System Limitations 5
2.2 Design Goals 6
3. PROTOCOL RESTRICTIONS 7
4. VOICE MESSAGE INTERCHANGE FORMAT 8
4.1 Message Addressing Formats 8
4.2 Message Header Fields 10
4.3 Message Content Types 15
4.4 Forwarded Messages 20
5. MESSAGE TRANSPORT PROTOCOL 21
5.1 ESMTP Commands 21
5.2 ESMTP Keywords 23
5.3 ESMTP Parameters - MAIL FROM 24
5.4 ESMTP Parameters - RCPT TO 24
5.5 ESMTP - SMTP Downgrading 24
6. DIRECTORY ADDRESS RESOLUTION 25
7. IMAP 25
8. MANAGEMENT PROTOCOLS 25
8.1 Network Management 25
9. CONFORMANCE REQUIREMENTS 26
Vaudreuil, Parsons Expires 3/9/97 [Page 2]
Internet Draft VPIM v2 September 9, 1996
10. REFERENCES 27
11. SECURITY CONSIDERATION 29
12. ACKNOWLEDGMENTS 29
13. AUTHORS' ADDRESSES 29
14. APPENDIX A - VPIM REQUIREMENTS SUMMARY 30
15. APPENDIX B - EXAMPLE VOICE MESSAGES 34
16. APPENDIX C - EXAMPLE ERROR VOICE PROCESSING ERROR CODES 37
17. APPENDIX D - AUDIO/32KADPCM CONTENT TYPE 38
18. APPENDIX E - IMAGE/TIFF CONTENT TYPE 39
18.1 References 39
18.2 TIFF Class F 39
19. APPENDIX F - CHANGE HISTORY: RFC 1911 TO THIS DOCUMENT 42
20. APPENDIX G -- OPEN ISSUES 43
Vaudreuil, Parsons Expires 3/9/97 [Page 3]
Internet Draft VPIM v2 September 9, 1996
1. Abstract
A class of special-purpose computers has evolved to provide voice
messaging services. These machines generally interface to a telephone
switch and provide call answering and voice messaging services.
Traditionally, messages sent to a non-local machine are transported
using analog networking protocols based on DTMF signaling and analog
voice playback. As the demand for networking increases, there is a
need for a standard high-quality digital protocol to connect these
machines. The following document is a profile of the Internet
standard MIME and ESMTP protocols for use as a digital voice messaging
networking protocol.
This profile is based on an earlier effort in the Audio Message
Interchange Specification (AMIS) group to define a voice messaging
protocol based on X.400 technology. This protocol is intended to
satisfy the user requirements statement from that earlier work with
the industry standard ESMTP/MIME mail protocol infrastructures already
used within corporate intranets. This Internet Draft will be referred
to as VPIM (Voice Profile for Internet Mail) in this document. This
second version of VPIM is based on implementation experience and
obsoletes RFC 1911 which describes version 1 of the profile.
Vaudreuil, Parsons Expires 3/9/97 [Page 4]
Internet Draft VPIM v2 September 9, 1996
2. Scope
MIME is the Internet multipurpose, multimedia messaging standard.
This document explicitly recognizes its capabilities and provides a
mechanism for the exchange of various messaging technologies,
highlighting voice and facsimile.
This document specifies a restricted profile of the Internet
multimedia messaging protocols for use between voice processing
platforms. These platforms have historically been special-purpose
computers and often do not have the same facilities normally
associated with a traditional Internet Email-capable computer. As a
result, VPIM also specifies additional functionality as it is needed.
This profile is intended to specify the minimum common set of features
to allow interworking between compliant systems.
2.1 Voice Messaging System Limitations
The following are typical limitations of voice messaging platform
which were considered in creating this baseline profile.
1) Text messages are not normally received and often cannot be
displayed or viewed. They can often be processed only via text-to-
speech or text-to-fax features not currently present in many of
these machines.
2) Voice mail machines usually act as an integrated Message
Transfer Agent, Message Store and User Agent. There is no relaying
of messages and RFC 822 header fields may have limited use in the
context of the limited messaging features currently deployed.
3) VM message stores are generally not capable of preserving the
full semantics of an Internet message. As such, use of a voice
mail machine for gatewaying is not supported. In particular,
storage of "CC" lists, "Received" lines, and "Message-ID" may be
limited.
4) Internet-style distribution/exploder mailing lists are not
typically supported. Voice mail machines often implement only
local alias lists, with error-to-sender and reply-to-sender
behavior. Reply-all capabilities using a CC list is not generally
available.
5) Error reports must be machine-parsable so that helpful responses
can be voiced to users whose only access mechanism is a telephone.
6) The voice mail systems generally limit address entry to 16 or
fewer numeric characters, and normally do not support alphanumeric
mailbox names. Alpha characters are not generally used for mailbox
identification as they cannot be easily entered from a telephone
terminal.
Vaudreuil, Parsons Expires 3/9/97 [Page 5]
Internet Draft VPIM v2 September 9, 1996
2.2 Design Goals
It is a goal of this effort to make as few restrictions and additions
to the existing Internet mail protocols as possible while satisfying
the requirements for interoperability with current generation voice
messaging systems. This goal is motivated by the desire to increase
the accessibility to digital messaging by enabling the use of proven
existing networking software for rapid development.
This specification is intended for use on a TCP/IP network, however,
it is possible to use the SMTP protocol suite over other transport
protocols. The necessary protocol parameters for such use is outside
the scope of this document.
This profile is intended to be robust enough to be used in an
environment such as the global Internet with installed base gateways
which do not understand MIME, though typical use is expected to be
within corporate intranets. Full functionality such, as reliable
error messages and binary transport, will require careful selection of
gateways (via MX records) to be used as VPIM forwarding agents.
Nothing in this document precludes use of a general purpose MIME email
packages to read and compose VPIM messages. While no special
configuration is required to receive VPIM compliant messages, some may
be required to originate compliant structures.
It is expected that a VPIM messaging system will be managed by a
system administrator who can perform TCP/IP network configuration.
When using facsimile or multiple voice encodings, it is suggested that
the system administrator maintain a list of the capabilities of the
networked mail machines to reduce the sending of undeliverable
messages due to lack of feature support. Configuration,
implementation and management of this directory listing capabilities
is a local matter.
Vaudreuil, Parsons Expires 3/9/97 [Page 6]
Internet Draft VPIM v2 September 9, 1996
3. Protocol Restrictions
This protocol does not limit the number of recipients per message.
Where possible, implementations should not restrict the number of
recipients in a single message. It is recognized that no
implementation supports unlimited recipients, and that the number of
supported recipients may be quite low. However, ESMTP currently does
not provide a mechanism for indicating the number of supported
recipients.
This protocol does not limit the maximum message length. Implementors
should understand that some machines will be unable to accept
excessively long messages. A mechanism is defined in the RFC 1425
SMTP service extensions to declare the maximum message size supported.
The message size indicated in the ESMTP SIZE command is in bytes, not
minutes or seconds. The number of bytes varies by voice encoding
format and must include the MIME wrapper overhead. If the length must
be known before sending, an approximate translation into minutes or
seconds can be performed if the voice encoding is known.
The following sections describe the restrictions and additions to
Internet mail that are required to be compliant with this VPIM v2
profile. A table in Appendix A summarizes the details.
Vaudreuil, Parsons Expires 3/9/97 [Page 7]
Internet Draft VPIM v2 September 9, 1996
4. Voice Message Interchange Format
The voice message interchange format is a profile of the Internet Mail
Protocol Suite. As such, this document assumes an understanding of
these specifications. Specifically, VPIM references components from
the message format standard for Internet messages [RFC822], the
Multipurpose Internet Message Extensions [MIME], the X.400 gateway
specification [X.400], delivery status notification
[DRPT][NOTIFY][STATUS], the message disposition notifications [MDN],
and the electronic business card [DIRECTORY][VCARD].
4.1 Message Addressing Formats
RFC 822 addresses are based on the domain name system. This naming
system has two components: the local part, used for username or
mailbox identification; and the host part, used for global machine
identification.
4.1.1 VPIM Addresses
The local part of the address shall be a US-ASCII string uniquely
identifying a mailbox on a destination system. For voice messaging,
the local part is a printable string containing the mailbox ID of the
originator or recipient. While alpha characters and long mailbox
identifiers are permitted, most voice mail networks rely on numeric
mailbox identifiers to retain compatibility with the limited 10 digit
telephone keypad. The use of the domain naming system should be
transparent to the user. It is the responsibility of the voice mail
machine to lookup the fully-qualified domain name (FQDN) based on the
address entered by the user (see Section 6).
In the absence of a global directory, specification of the local part
is expected to conform to international or private telephone numbering
plans. It is likely that private numbering plans will prevail and
these are left for local definition. However, public telephone
numbers will be noted according to the international numbering plan
described in [E.164] and will be preceded by a `+'. The specification
of the local part of a VPIM address can be split into the four groups
described below:
1) mailbox number
- for use as a private numbering plan (any number of digits)
- e.g. 2722@octel.com
2) mailbox number+extension
- for use as a private numbering plan with extensions
any number of digits, use of `+' as separator
- e.g. 2722+111@octel.com
3) +international number
- for international telephone numbers conforming to E.164
maximum of 15 digits
- e.g. +16137637582@vm.nortel.ca
Vaudreuil, Parsons Expires 3/9/97 [Page 8]
Internet Draft VPIM v2 September 9, 1996
4) +international number+extension
- for international telephone numbers conforming to E.164
maximum of 15 digits, with an extension (e.g. behind a
PBX) that has a maximum of 15 digits.
- e.g. +17035245550+230@ema.org
4.1.2 Special Addresses
Special addresses are provided for compatibility with the conventions
of Internet mail and to facilitate testing. These addresses do not
use numeric local addresses, both to conform to current Internet
practice and to avoid conflict with existing numeric addressing plans.
Two special addresses are RESERVED for use as follows:
Postmaster@domain
By convention, a special mailbox named "postmaster" MUST exist on all
systems. This address is used for diagnostics and should be checked
regularly by the system manager. This mailbox is particularly likely
to receive text messages, which is not normal on a voice processing
platform. The specific handling of these messages is an individual
implementation choice.
Loopback@domain
A special mailbox name named "loopback" SHOULD be designated for
loopback testing. If supported, all messages (including content) sent
to this mailbox MUST be returned back to the address listed in the
From: address as a new message. The originating address of the
returned address MUST be "postmaster" to prevent mail loops.
4.1.3 Distribution Lists
There are many ways to handle distribution list (DL) expansions and
none are 'standard'. Simple alias is a behavior closest to what most
voice mail systems do today and what is to be used with VPIM messages.
That is:
Reply to the originator - (Address in the RFC822 From field)
Errors to the submitter - (Address in the MAIL FROM: field of the
ESMTP exchange and the Return-Path:
RFC 822 field)
Some proprietary voice messaging protocols include only the recipient
of the particular copy in the envelope and include no "headers" except
date and per-message features. Most voice messaging systems do not
provide for "Header Information" in their messaging queues and only
include delivery information. As a result, recipient information MAY
be in either the To or CC headers. Other recipients MAY optionally be
included, however it is often not accurate enough for the reply-all
capability.
Vaudreuil, Parsons Expires 3/9/97 [Page 9]
Internet Draft VPIM v2 September 9, 1996
4.2 Message Header Fields
Internet messages contain a header information block. This header
block contains information required to identify the sender, the list
of recipients, the message send time, and other information intended
for user presentation. Except for specialized gateway and mailing
list cases, headers do not indicate delivery options for the transport
of messages.
Exploder lists are noted for modifying or adding to the headers of
messages that pass through them. VPIM systems MUST be able to accept
and ignore headers that are not defined here.
The following header lines are permitted for use with VPIM voice
messages:
4.2.1 From
The originator's fully-qualified domain address (a mailbox address
followed by the fully-qualified domain name). The user listed in this
field should be presented in the voice message envelope as the
originator of the message.
Systems compliant with this profile SHOULD provide the text personal
name of the sender in a quoted phrase if the name is available. To
facilitate storage of the text name in a local dial-by-name cache
directory, the first and last name names must be separable. Text
names of persons in voice messages MUST be represented in the form
"last, first, mi." and MUST be the same as found in the Vcard (section
4.3.4), if present. Text names of corporate or positional mailboxes
MAY be provided as a simple string. From [822]
Example:
From: "User, Joe, S." <2145551212@mycompany.com>
From: "Technical Support" <611@serviceprovider.com>
If a From: address is present, it MAY be used to construct a reply
message to the sender.
Vaudreuil, Parsons Expires 3/9/97 [Page 10]
Internet Draft VPIM v2 September 9, 1996
4.2.2 To
The To header contains the recipient's fully-qualified domain address.
There may be one or more To: fields in any message.
Example:
To: 2145551213@mycompany.com
Systems compliant to this profile SHOULD provide a list of recipients
only if all recipients can be provided. The To header MUST NOT be
included in the message if the sending message transport agent (MTA)
cannot resolve all the addresses in it, e.g. if an address is a DL
alias for which the expansion is unknown (see section 4.1.3). If
present, the addresses in the To header MAY be uses for a reply
message to all primary recipients.
4.2.3 cc
The cc header contains additional recipients' fully-qualified domain
addresses. Many voice mail systems maintain only sufficient envelope
information for message delivery and are not capable of storing or
providing a complete list of recipients. Systems compliant to this
profile SHOULD provide a list of recipients only if all disclosed
recipients can be provided. The list of disclosed recipients does not
include those sent via a blind copy. If not, systems SHOULD omit the
CC headers to indicate that the full list of recipients is unknown.
Example:
cc: 2145551213@mycompany.com
Systems compliant to this profile MAY discard the cc addresses of
incoming messages as necessary. If a list of CC addresses is
present, these addresses MAY be used for a reply message to all
recipients.
4.2.4 Date
The Date header contains the date, time, and time zone in which the
message was sent by the originator. The time zone SHOULD be
represented in a four-digit time zone offset, such as -0600 for North
American Eastern Standard Time. This may be supplemented by a time
zone name in parentheses, e.g., "-0800 (PDT)". Compliant
implementations SHOULD be able to convert RFC 822 date and time stamps
into local time.
Example:
Date: Wed, 28 Jul 96 10:08:49 -0900 (PST)
The sending system MUST report the time the message was sent. From
[822]
Vaudreuil, Parsons Expires 3/9/97 [Page 11]
Internet Draft VPIM v2 September 9, 1996
4.2.5 Sender
The Sender header contains the actual address of the originator if the
message is sent by an agent on behalf of the author indicated in the
From: field and MAY be present in a VPIM message.
While it may not be possible to save this information in some voice
mail machines, discarding this information or the ESMTP MAIL FROM
address will make it difficult to send an error message to the proper
destination. From [822]
4.2.6 Message-id
The Message-id header contains a unique per-message identifier. A
unique message-id MUST be generated for each message sent from a
compliant implementation.
The message-id is not required to be stored on the receiving system.
This identifier MAY be used for tracking, auditing, and returning
read-receipt reports. From [822]
Example:
Message-id: <12345678@mycompany.com>
4.2.7 Received
The Received header contains trace information added to the beginning
of a RFC 822 message by MTAs. This is the only header permitted to be
added by an MTA. Information in this header is useful for debugging
when using an US-ASCII message reader or a header parsing tool.
A compliant system MUST add Received headers when acting as a gateway
and MUST NOT remove any. These headers MAY be ignored or deleted when
the message is received at the final destination. From [822]
4.2.8 MIME Version
The MIME-Version header indicates that the message conforms to the
MIME message format specification. Systems compliant with this
specification MUST include a comment with the words "(Voice 2.0)". RFC
1911 defines an earlier version of this profile and uses the token
(Voice 1.0). From [MIME][VPIM1]
Example:
MIME-Version: 1.0 (Voice 2.0)
Vaudreuil, Parsons Expires 3/9/97 [Page 12]
Internet Draft VPIM v2 September 9, 1996
4.2.9 Content-Type
The content-type header declares the type of content enclosed in the
message. One of the allowable contents is multipart/mixed, a
mechanism for bundling several message components into a single
message. The allowable contents are detaileded in the section 4.3 of
this document. From [MIME]
4.2.10 Content-Transfer-Encoding
Because Internet mail was initially specified to carry only 7-bit US-
ASCII text, it may be necessary to encode voice and fax data into a
representation suitable for that environment. The content-transfer-
encoding header describes this transformation if it is needed.
Compliant implementations MUST recognize and decode the standard
encodings, "Binary", "7bit, "8bit", "Base64" and "Quoted-Printable".
The allowable content-transfer-encodings are specified in section 4.3.
From [MIME]
4.2.11 Sensitivity
The sensitivity header, if present, indicates the requested privacy
level. The case-insensitive values "Personal" and "Private" are
specified. If no privacy is requested, this field is omitted.
If a sensitivity header is present in the message, a compliant system
MUST prohibit the recipient from forwarding this message to any other
user. A compliant system, however, SHOULD allow the user to reply to
a sensitive message, but SHOULD NOT include the original message
content. The sensitivity of the reply message MAY be set by the user.
If the receiving system does not support privacy and the sensitivity
is one of "Personal" or "Private", the message MUST be returned to the
sender with an appropriate error code indicating that privacy could
not be assured and that the message was not delivered. A non-delivery
notification to a private message need not be tagged private since it
will be sent to the originator. From: [X.400]
4.2.12 Importance
Indicates the requested priority to be given by the receiving system.
The case-insensitive values "low", "normal" and "high" are specified.
If no special importance is requested, this header may be omitted and
the value assumed to be "normal".
Compliant implementations MAY use this header to indicate the
importance of a message and may order messages in a recipient's
mailbox. From: [X400]
Vaudreuil, Parsons Expires 3/9/97 [Page 13]
Internet-Draft VPIM v2 September 9, 1996
4.2.13 Subject
The subject field is often provided by email systems but is not widely
supported on Voice Mail platforms. For compatibility with text based
mailbox interfaces, a text subject field SHOULD be generated by a
compliant implementation but MAY be discarded if present by a
receiving system. From [822]
It is recommended that voice messaging systems that do not support any
text user interfaces (e.g. access only by a telephone) insert a
generic subject header of "VPIM Message" for the benefit of text
enabled recipients.
Vaudreuil, Parsons Expires 3/9/97 [Page 14]
Internet Draft VPIM v2 September 9, 1996
4.3 Message Content Types
MIME, introduced in [MIME], is a general-purpose message body format
that is extensible to carry a wide range of body parts. It provides
for encoding binary data so that it can be transported over the 7-bit
text-oriented SMTP protocol. This transport encoding is in addition
to the audio encoding required to generate a binary object.
MIME defines two transport encoding mechanisms to transform binary
data into a 7 bit representation, one designed for text-like data
("Quoted-Printable"), and one for arbitrary binary data ("Base64").
While Base64 is dramatically more efficient for audio data, both will
work. Where binary transport is available, no transport encoding is
needed, and the data can be labeled as "Binary".
An implementation in compliance with this profile SHOULD send audio
and/or facsimile data in binary form when binary message transport is
available. When binary transport is not available, implementations
MUST encode the audio and/or facsimile data as Base64. The detection
and decoding of "Quoted-Printable", "7bit", and "8bit" MUST be
supported in order to meet MIME requirements and to preserve
interoperability with the fullest range of possible devices. However,
if a content is received that cannot be rendered to the user, an
appropriate non-delivery notifcation MUST be sent.
The content types described in this section are identified for use
with this profile. Each of these contents can be sent individually in
a VPIM message or wrapped in a multipart/mixed to form a more complex
structure (several examples are given in Appendix B). When mulitple
contents are present, they SHOULD be presented to the user in the
order that they appear in the message.
4.3.1 Text/Plain
MIME requires support of the basic Text/Plain content type. This
content type has limited applicability within the voice messaging
environment. Compliant implementations SHOULD NOT send the Text/Plain
content-type and SHOULD only send this content if the recipient system
is known to support it. Compliant implementations MUST accept
Text/Plain messages, however, specific handling is left as an
implementation decision. From [MIME]
There are several mechanisms that can be used to support text on voice
messaging systems including text-to-speech and text-to-fax
conversions. If no rendering of the text is possible (i.e. it is not
possible to determine if the text is a critical part of the message),
the entire message MUST be non-delivered and returned to the sender
with a media-unsupported error code.
Vaudreuil, Parsons Expires 3/9/97 [Page 15]
Internet Draft VPIM v2 September 9, 1996
4.3.2 Multipart/Mixed
MIME provides the facilities for enclosing several body parts in a
single message. Multipart/Mixed SHOULD be used for sending multi-
segment voice messages, that is, to preserve across the network the
distinction between an annotation and a forwarded message, or between
a spoken subject and the voice message. Compliant systems MUST accept
multipart/mixed body parts. Systems MAY collapse such a multi-segment
voice or fax message into a single segment if multi-segment messages
are not supported on the receiving machine. From [MIME]
While any valid MIME body header MAY be used, the following header has
specific semantics when included with this body part:
4.3.2.1 Content-Description:
This field SHOULD be present to allow the text identification of
this body part as being a VPIM message. This is particulary useful
for identification when using a simple MIME mail package. If there
are multiple multipart/mixed bodies present, then this header MUST
be present to allow differentiation. It is recommended that the
value `VPIM Message' be used to identify content compliant with
this document.
4.3.3 Message/RFC822
MIME requires support of the Message/RFC822 message encapsulation body
part. This body part is used within a multipart/mixed message to
forward complete messages (see section 4.4) or to reply with original
content. From [MIME]
4.3.4 Application/Directory
The spoken name and the spelled name of the message sender SHOULD be
sent with each message in an Application/Directory content type
[DIRECTORY]. If included in a message, the Versit VCARD profile MUST
be used [VCARD] and MUST specify at least the following attributes:
TEL - telephone number (various types, typically VOICE)
EMAIL - email address (various types, typically INTERNET)
The following attributes SHOULD be specified:
N - Family Name, Given Name, Additional Names, Honorific Prefixes,
and Suffixes (all present components in the From text name MUST
match)
ROLE - alternative to `N' attribute when sender is a corporate or
positional mailbox
SOUND - sound data (various types, typically 32KADPCM)
REV - Revision of Vcard in ISO 8601 date format
The content MAY use the other types (e.g. capabilities) as defined in
[VCARD].
Vaudreuil, Parsons Expires 3/9/97 [Page 16]
Internet Draft VPIM v2 September 9, 1996
The spoken name SHOULD be denoted by a content ID pointing to an
audio/* content elsewhere in the VPIM message. Alternatively, the
spoken name MAY be included inline in the "SOUND" type using a Base64
encoding of typically 32KADPCM. However, it MUST NOT be denoted using
an URL.
For the Vcard to be identified as the sender's, it MUST include the
EMAIL token 'VPIM' and match the address in the From: header. The
Name, if present, SHOULD NOT be used for comparison since the Vcard
has more components.
There MUST only be one Vcard per VPIM message. If more than one is
present it is an error condition, all Vcards not associated with with
the sender may be discarded.
Example:
BEGIN: vCard
N: Parsons;Glenn
ORG: Nortel Technology
TEL;TYPE=VOICE,MSG,WORK: +1-613-763-7582
EMAIL;TYPE=INTERNET: glenn.parsons@nortel.ca
EMAIL;TYPE=INTERNET,VPIM: 6137637582@vm.nortel.ca
SOUND;TYPE=32KADPCM;ENCODE=BASE64;VALUE=INLINE:
iIiIiIjMzN3czdze3s7d7fwfHhcvESJVe/4yEhLz8/FOQjVFRERCESL/zqrq
(This is the Spoken Name audio data) 3Or/zrPCzxv43u3L7buR3b0
AAEAAAAIAAAAFQEDAAEAAAABAAAAFgEEAAEAAACqCAAAFwEEAAEAAAD1uQEA
GgEFAAEAAAAIugEAGwEFAAEAAAAQugEAJAEEAAEAAAAEAAAAAAAAAA==
REV: 19960831T103310Z
END: vCard
Vaudreuil, Parsons Expires 3/9/97 [Page 17]
Internet Draft VPIM v2 September 9, 1996
4.3.5 Audio/32KADPCM
CCITT Recommendation G.726 [G726] describes the algorithm recommended
for conversion of a 64 kbit/s A-law or u-law PCM channel to and from a
32 kbit/s channel (this is the same algorithm as the deprecated
G.721). The conversion is applied to the PCM stream using an Adaptive
Differential Pulse Code Modulation (ADPCM) transcoding technique.
An implementation compliant to this profile MUST use Audio/32KADPCM by
default for voice. Typically this body contains several minutes of
message content, however if used for spoken name or subject the
content should be considerably shorter (i.e. about 10 and 20 seconds
respectively).
While any valid MIME body header MAY be used, several headers have the
following semantics when included with this body part:
4.3.5.1 Content-Description:
This field SHOULD be present to allow the parsable text
identification of these body parts. If more than one
Audio/32KADPCM body occurs within a single multipart/mixed, then
this header MUST be present to allow differentiation. It is
recommended that the following text values be used as appropriate:
Voice Message - the primary voice message,
Originator Spoken Name - the spoken name of the originator,
Recipient Spoken Name - the spoken name of the recipient if
available to the originator and present if there is ONLY one
recipient,
Spoken Subject.- the spoken subject of the message, typically
spoken by the originator
4.3.5.2 Content-Duration:
This field MAY be present to allow the specification of the length
of the bodypart in seconds. The use of this field on reception is
a local implementation issue. The formal BNF for this header is:
duration := "Content-Duration" ":" 1*6DIGIT "seconds"
Example:
Content-Duration: 33 seconds
4.3.5.3 Content-Language:
This field MAY be present to allow the specification of the spoken
language of the bodypart. The encoding is defined in [LANG] (e.g.
EN-UK for UK English). The use of this field on reception is a
local implementation issue.
Vaudreuil, Parsons Expires 3/9/97 [Page 18]
Internet Draft VPIM v2 September 9, 1996
4.3.6 Proprietary Voice Formats
Proprietary voice encoding formats or other standard formats may be
supported under this profile provided a unique identifier is
registered with the IANA prior to use. These voice encodings should
be registered as sub-types of Audio.
Use of any other encoding except Audio/32KADPCM reduces
interoperability in the absence of explicit manual system
configuration. A compliant implementation MAY use any other encoding
with explicit per-destination configuration.
4.3.7 Image/TIFF
All implementations MUST generate and read TIFF-F [TIFF][S100]
compatible facsimile contents. The tags that MUST be supported by
systems complying to this recommendation are described in the
Enterprise Computer Telephony Forum's S.100 API specification [S100].
The TIFF-F content, originally from [TPC.INT] has been refined to
reflect this common practice, and is summarized in Appendix E for
completeness.
4.3.8 Multipart/report
An implementation MAY send this fax content in VPIM messages and MUST
be able to recognize it in received messages. If a fax message is
received that cannot be rendered to the user, then the system MUST
non-deliver the entire message with a media not supported error.
Multipart/Report
The Multipart/Report is used for enclosing a Message/Notification and
Message/Disposition-notification body parts and any returned message
content. Compliant implementations MUST use the Multipart/Report
construct when returning messages, sending warnings, or issuing read
receipts. Compliant implementations MUST recognize and decode the
Multipart/Report content type. From [REPORT]
4.3.9 Message/Notification
This MIME body part is used for sending machine-parsable delivery
status notifications. Compliant implementations must use the
Message/Notification construct when returning messages or sending
warnings. Compliant implementations must recognize and decode the
Message/Notification content type and present the reason for failure
to the user. From [NOTIFY]
4.3.10 Message/Disposition-notification
This MIME body part is used for sending machine-parsable read-receipt
and extended-absence status notifications. Compliant implementations
must use the Message/Disposition-notification construct when sending
post-delivery message status notifications. Compliant implementations
must recognize and decode the Message/Disposition-notification content
type and present the reason for failure to the user. From [MDN]
Vaudreuil, Parsons Expires 3/9/97 [Page 19]
Internet Draft VPIM v2 September 9, 1996
4.4 Forwarded Messages
VPIM version 2 explicitly supports the forwarding of voice and fax
content with voice or fax annotation. Forwarded VPIM messages SHOULD
be sent as a multipart/mixed with the entire original message enclosed
in a message/rfc822 content type and the annotation as a separate
Audio/* body part.
In the event that the RFC822 headers are not available for the
forwarded content, simulated headers with information as available
SHOULD be constructed to indicate the original sending timestamp, and
the original sender as indicated in the "From" line. The
message/rfc822 content MUST include at least the MIME-Version: 1.0
(Voice 2.0), the MIME content type and MIME content-encoding header as
necessary.
In the event that forwarding information is lost through concatenation
of the original message and the forwarding annotation, such as must be
done in an AMIS to VPIM gateway, the entire content MAY be sent as a
single Audio/* segment without including any forwarding semantics.
Vaudreuil, Parsons Expires 3/9/97 [Page 20]
Internet Draft VPIM v2 September 9, 1996
5. Message Transport Protocol
Messages are transported between voice mail machines using the
Internet Extended Simple Mail Transfer Protocol (ESMTP). All
information required for proper delivery of the message is included in
the ESMTP dialog. This information, including the sender and
recipient addresses, is commonly referred to as the message
"envelope". This information is equivalent to the message control
block in many analog voice networking protocols.
ESMTP is a general-purpose messaging protocol, designed both to send
mail and to allow terminal console messaging. Simple Mail Transport
Protocol (SMTP) was originally created for the exchange of US-ASCII 7-
bit text messages. Binary and 8-bit text messages have traditionally
been transported by encoding the messages into a 7-bit text-like form.
[ESMTP] formalized an extension mechanism for SMTP, and subsequent
RFCs have defined 8-bit text networking, command streaming, binary
networking, and extensions to permit the declaration of message size
for the efficient transmission of large messages such as multi-minute
voice mail.
The following sections list ESMTP commands, keywords, and parameters
that are required and those that are optional.
5.1 ESMTP Commands
5.1.1 HELO
Base SMTP greeting and identification of sender. This command is not
to be sent by compliant systems unless the more-capable EHLO command
is not accepted. It is included for compatibility with general SMTP
implementations. Compliant implementations MUST implement the HELO
command for backward compatibility but SHOULD NOT send it unless EHLO
is not supported. From [SMTP]
5.1.2 MAIL FROM (REQUIRED)
Originating mailbox. This address contains the mailbox to which
errors should be sent. This address may not be the same as the
message sender listed in the message header fields if the message was
received from a gateway or sent to an Internet-style mailing list.
Compliant implementations MUST implement the extended MAIL FROM
command. From [SMTP, ESMTP]
5.1.3 RCPT TO
Recipient's mailbox. This field contains only the addresses to which
the message should be delivered for this transaction. In the event
that multiple transport connections to multiple destination machines
are required for the same message, this list may not match the list of
recipients in the message header. Compliant implementations MUST
implement the extended RCPT TO command. From [SMTP, ESMTP]
Vaudreuil, Parsons Expires 3/9/97 [Page 21]
Internet Draft VPIM v2 September 9, 1996
5.1.4 DATA
Initiates the transfer of message data. Support for this command is
required in the event the binary mode command BDAT is not supported by
the remote system. Compliant implementations MUST implement the SMTP
DATA command for backwards compatibility. From [SMTP]
5.1.5 TURN
Requests a change-of-roles, that is, the client that opened the
connection offers to assume the role of server for any mail the remote
machine may wish to send. Because SMTP is not an authenticated
protocol, the TURN command presents an opportunity to improperly fetch
mail queued for another destination. Compliant implementations SHOULD
NOT implement the TURN command. From [SMTP]
5.1.6 QUIT
Requests that the connection be closed. If accepted, the remote
machine will reset and close the connection. Compliant
implementations MUST implement the QUIT command. From [SMTP]
5.1.7 RSET
Resets the connection to its initial state. Compliant implementations
MUST implement the RSET command. From [SMTP]
5.1.8 VRFY
Requests verification that this node can reach the listed recipient.
While this functionality is also included in the RCPT TO command, VRFY
allows the query without beginning a mail transfer transaction. This
command is useful for debugging and tracing problems. Compliant
implementations MAY implement the VRFY command. From [SMTP]
(Note that the implementation of VRFY may simplify the guessing of a
recipient's mailbox or automated sweeps for valid mailbox addresses,
resulting in a possible reduction in privacy. Various implementation
techniques may be used to reduce the threat, such as limiting the
number of queries per session.) From [SMTP]
5.1.9 EHLO
The enhanced mail greeting that enables a server to announce support
for extended messaging options. The extended messaging modes are
discussed in subsequent sections of this document. Compliant
implementations MUST implement the ESMTP command and return the
capabilities indicated later in this memo. From [ESMTP]
Vaudreuil, Parsons Expires 3/9/97 [Page 22]
Internet Draft VPIM v2 September 9, 1996
5.1.10 BDAT
The BDAT command provides a higher efficiency alternative to the
earlier DATA command, especially for voice. The BDAT command provides
for native binary transport of messages. Compliant implementations
SHOULD support binary transport using the BDAT command.[BINARY]
5.2 ESMTP Keywords
The following ESMTP keywords indicate extended features useful for
voice messaging.
5.2.1 PIPELINING
The "PIPELINING" keyword indicates ability of the receiving server to
accept pipelined commands. Pipelining commands dramatically improves
performance by reducing the number of round-trip packet exchanges and
makes it possible to validate all recipient addresses in one
operation. Compliant implementations SHOULD support the command
pipelining indicated by this parameter. From [PIPE]
5.2.2 SIZE
The "SIZE" keyword provides a mechanism by which the SMTP server can
indicate the maximum size message supported. Compliant
implementations MUST provide the size capability and SHOULD honor any
size limitations when sending. From [SIZE]
5.2.3 CHUNKING
The "CHUNKING" keyword indicates that the receiver will support the
high-performance binary transport mode. Note that CHUNKING can be
used with any message format and does not imply support for binary
encoded messages. Compliant implementations SHOULD support binary
transport indicated by this capability. From [BINARY]
5.2.4 BINARYMIME
The "BINARYMIME" keyword indicates that the SMTP server can accept
binary encoded MIME messages. Compliant implementations SHOULD support
binary transport indicated by this capability. From [BINARY]
5.2.5 NOTIFY
The "NOTIFY" keyword indicates that the SMTP server will accept
explicit delivery status notification requests. Compliant
implementations MUST support the delivery notification extensions in
[DSN].
Vaudreuil, Parsons Expires 3/9/97 [Page 23]
Internet Draft VPIM v2 September 9, 1996
5.2.6 ENHANCEDSTATUSCODES
The "EHNAHCEDSTATUSCODES" keyword indicates that an SMTP server
augments its responses with the enhanced mail system status codes
[CODES]. These codes can then be used to provide more informative
explanations of error conditions, especially in the context of the
delivery status notifications format defined in [NOTARY]. Compliant
implementations SHOULD support this capability. From [STATUS]
5.3 ESMTP Parameters - MAIL FROM
5.3.1 BINARYMIME
The current message is a binary encoded MIME messages. Compliant
implementations SHOULD support binary transport indicated by this
parameter. From [BINARY]
5.4 ESMTP Parameters - RCPT TO
5.4.1 NOTIFY
The NOTIFY parameter indicates the conditions under which a delivery
report should be sent. Compliant implementations MUST honor this
request. From [DSN]
5.4.2 RET
The RET parameter indicates whether the content of the message should
be returned. Compliant systems SHOULD honor a request for returned
content. From [DSN]
5.5 ESMTP - SMTP Downgrading
To ensure a consistant level of service across an intranet or the
global Internet, it is essential that VPIM compliant ESMTP be
supported at all hops between a VPIM originating system and the
recipient system. Unfortunately, in the situation where a `downgrade'
is unavoidable the expected result is not defined. However, it is
recommended that the downgrading system should continue to attempt to
deliver the message via SMTP, but MUST send a delivery notification to
the originator indicating that the message left an ESMTP host and was
sent (unreliably) via SMTP.
Vaudreuil, Parsons Expires 3/9/97 [Page 24]
Internet Draft VPIM v2 September 9, 1996
6. Directory Address Resolution
It is the responsibility of a VPIM system to lookup the fully-
qualified domain name (FQDN) based on the address entered by the user
(if the entered address is not already a FQDN). This would typically
be an issue on systems that offered only a telephone user interface.
The mapping of the dialed target number to a routable address allowing
delivery to the destination system can be accomplished through
implementation-specific means.
An implementations may wish to populate local directories with address
information extracted from received messages. It is mandated that
only address information from Vcard attachments to VPIM messages be
used to populate such a directory when the Vcard is available.
Stripping addresses from the headers of VPIM messages SHOULD NOT be
used to populate directories as it only provides partial data.
Alternatively, bilateral agreements could be made to allow the bulk
transfer of Vcards between systems.
7. IMAP
The use of client/server desktop mailbox protocols like IMAP or POP to
retrieve VPIM messages from a IMAP or POP message store is possible
without any special modifications to this VPIM specification. Email
clients (and web browsers) typically have a table for mapping from
MIME type to displaying application. The audio/*, image/tiff and
application/directory contents can be configured so that they invoke
the correct player/recorder for rendering. In addition with IMAP
clients, the first multipart/mixed content (if present) will not
appear since it is generic. The user instead will be presented with a
message that has (for example) audio and image contents.
8. Management Protocols
The Internet protocols provide a mechanism for the management of
messaging systems, from the management of the physical network through
the management of the message queues. SNMP should be supported on a
compliant message machine.
8.1 Network Management
The digital interface to the VM and the TCP/IP protocols SHOULD be
managed. MIB II SHOULD be implemented to provide basic statistics and
reporting of TCP and IP protocol performance. [MIB II]
Authors Note: Last time I checked, MADMAN was being rewritten for
submission again as proposed standard. Without a profile, I don't
think we should require this. Fine. Do you still want to require MIB
II?
Vaudreuil, Parsons Expires 3/9/97 [Page 25]
Internet Draft VPIM v2 September 9, 1996
9. Conformance Requirements
In order to claim conformance to this document and be called `VPIM
compliant', a voice messaging system must implement all mandatory
features of this profile in each of three areas: Content, Transport,
and Notifications. In addition, systems which conform to this profile
must not send messages with features beyond this profile unless
explicit per-destination configuration of these enhanced features is
provided. Such configuration information could be stored in a
directory, though the implementation of this is currently a local
matter.
It is also possible, though not encouraged, to claim conformance to
only specific areas (e.g. VPIM content compliant) of this profile.
The delineation of these areas is as follows:
Content - Section 4.24, except REPORT, NOTIFY & MDN, and
Section 6
Transport - Section 5 except NOTIFY & RET, and Section 8
Notifications - REPORT, NOTIFY & MDN from Section 4, NOTIFY &
RET from Section 5 and all notification
requirements.
A summary of compliance requirements is contained in Appendix A.
Vaudreuil, Parsons Expires 3/9/97 [Page 26]
Internet Draft VPIM v2 September 9, 1996
10. References
[AMIS-A] Audio Messaging Interchange Specifications (AMIS) - Analog
Protocol Version 1, Issue 2, February 1992
[AMIS-D] Audio Messaging Interchange Specifications (AMIS) - Digital
Protocol Version 1, Issue 3 August 1993
[MIME] Borenstein, N., and N. Freed, "Multipurpose Internet Mail
Extensions", RFC 1521, Bellcore, Innosoft, Sept 1993.
[MSG822] Crocker, D., "Standard for the Format of ARPA Internet Text
Messages", STD 11, RFC 822, UDEL, August 1982.
[X.400] Hardcastle-Kille, S., "Mapping between X.400(1988) / ISO 10021
and RFC 822", RFC 1327, May 1992.
[PIPE] Freed, N., Cargille, A., "SMTP Service Extension for Command
Pipelining" RFC 1854, October 1995.
[ESMTP] Klensin, J., Freed, N., Rose, M., Stefferud, E., and D. Crocker,
"SMTP Service Extensions" RFC 1869, United Nations University,
Innosoft International, Inc., Dover Beach Consulting, Inc., Network
Management Associates, Inc., The Branch Office, November 1995.
[SIZE] Klensin, J, Freed, N., Moore, K, "SMTP Service Extensions for
Message Size Declaration" RFC 1870, United Nations University,
Innosoft International, Inc., November 1995.
[8BIT] Klensin, J., Freed, N., Rose, M., Stefferud, E., D. Crocker,
"SMTP Service Extension for 8bit-MIMEtransport" RFC 1426, United
Nations University, Innosoft International, Inc., Dover Beach
Consulting, Inc., Network Management Associates, Inc., The Branch
Office, February 1993.
[DNS1] Mockapetris, P., "Domain names - implementation and
specification", RFC1035, Nov 1987.
[DNS2] Mockapetris, P., "Domain names - concepts and facilities", RFC
1034, Nov 1987.
[SMTP] Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC 821,
USC/Information Sciences Institute, August 1982.
[BINARY] Vaudreuil, G., "SMTP Service Extensions for Transmission of
Large and Binary MIME Messages", RFC 1830, October 1995.
[NOTIFY] Moore, K., Vaudreuil, G., "An Extensible Message Format for
Delivery Status Notifications", RFC 1894, 01/15/1996.
[REPORT] Vaudreuil, G., "The Multipart/Report Content Type for the
Reporting of Mail System Administrative Messages", RFC 1892,
01/15/1996.
Vaudreuil, Parsons Expires 3/9/97 [Page 27]
Internet Draft VPIM v2 September 9, 1996
[DSN] Moore, K. "SMTP Service Extensions for Delivery Status
Notifications", RFC 1891, 01/15/1996
[CODES] Vaudreuil, G. "Enhanced Mail System Status Codes", RFC 1893,
01/15/1996.
[STATUS] Freed, N. "SMTP Service Extension for Returning Enhanced Error
Codes", Internet-Draft <draft-freed-smtperror-01.txt>, July 1996.
[G726] CCITT Recommendation G.726 (1990), General Aspects of Digital
Transmission Systems, Terminal Equipment - 40, 32, 24,16 kbit/s
Adaptive Differential Pulse Code Modulation (ADPCM).
[MADMAN] N. Freed, S. Kille, "Mail Monitoring MIB", RFC 1566, Jan 1994.
[MIB II] M. Rose, "Management Information Base for Network Management of
TCP/IP-based internets: MIB-II", RFC 1158, May 1990.
[RELATED] Levinson, E., "The MIME Multipart/Related Content-Type", RFC
1872, Dec 1995
[MDN] Fajman, Roger, "An Extensible Message Format for Message
Disposition Notifications" <draft-ietf-receipt-MDN-00.txt>
[DIRECTORY] Howes, Tim, Smith, Mark, A MIME Content-Type for Directory
Information" <draft-ietf-asid-mime-direct-01.txt>
[VCARD] Dawson, Frank, Howes, Tim, "An Application/Directory MIME
Content-Type Electronic Business Card Profile" <draft-ietf-asid-mime-
vcard-00.txt>
[LANG] Alvestrand,H., "Tags for the Identification of Languages", RFC
1766, Mar 1995
[TPC.INT] C. Malamud, M. Rose, "Principles of Operation for the TPC.INT
Subdomain: Remote Printing -- Technical Procedures", RFC 1528,
10/06/1993
[VPIM1] Vaudreuil, Greg, "Voice Profile for Internet Mail", RFC 1911,
Feb 1996.
[TIFF] Adobe Developers Association, TIFF (TM) Revision 6.0 - Final,
June 3, 1992.
[S100] Enterprise Computer Telephony Forum, S.100 Revision 1.0 - Media
Services "C" Language - Application Programming Interfaces, February
1996.
Vaudreuil, Parsons Expires 3/9/97 [Page 28]
Internet Draft VPIM v2 September 9, 1996
11. Security Consideration
This document is a profile of existing Internet mail protocols. As
such, it does not create any security issues not already existing in
the profiled Internet mail protocols themselves.
Further, the profile specified in this document does not in any way
preclude the use of any Internet mail security protocol to encrypt,
authenticate, or non-repudiate the messages.
12. Acknowledgments
The authors would like to offer a special thanks to the Electronic
Messaging Association, especially the members of the Voice Messaging
Committee, for their support of the VPIM specification and the efforts
they have made to ensure its success.
13. Authors' Addresses
Glenn W. Parsons
Nortel Technology
P.O. Box 3511, Station C
Ottawa, ON K1Y 4H7
Canada
Phone: +1-613-763-7582
Fax: +1-613-763-8385
Glenn.Parsons@Nortel.ca
Gregory M. Vaudreuil
Octel Network Services
17080 Dallas Parkway
Dallas, TX 75248-1905
United States
Phone/Fax: +1-214-733-2722
Greg.Vaudreuil@Octel.Com
Vaudreuil, Parsons Expires 3/9/97 [Page 29]
Internet Draft VPIM v2 September 9, 1996
14. Appendix A - VPIM Requirements Summary
The following table summarizes the profile of VPIM version 2 detailed
in this document. For complete explanations of each feature it is
recommended to read the accompanying text. The conformance table is
separated into various columns:
Feature - name of protocol feature
Section - reference section in main text of this document
Area - conformance area to which each feature applies:
C - content
T - transport
N - notifications
Status - whether the feature is mandatory, optional, or prohibited.
There are three different degrees of optional used in this table:
Must - mandatory
Should - encouraged optional
May - optional
Should not - discouraged optional
Must not - prohibited
Footnote - special comment about conformance for a particular
feature
Vaudreuil, Parsons Expires 3/9/97 [Page 30]
Internet Draft VPIM v2 September 9, 1996
VPIM version 2 Conformance
| | | | |S| |
| | | | | |H| |F
| | | | | |O|M|o
| | | |S| |U|U|o
| | | |H| |L|S|t
| |A|M|O| |D|T|n
| |R|U|U|M| | |o
| |E|S|L|A|N|N|t
| |A|T|D|Y|O|O|t
FEATURE |SECTION | | | | |T|T|e
-------------------------------------------|----------|-|-|-|-|-|-|-
| | | | | | | |
Message Addressing Formats: | | | | | | | |
Use DNS host names |4.1 |C|x| | | | |
Use only numbers in mailbox IDs |4.1.1 |C| |x| | | |
Use alpha-numeric mailbox IDs |4.1.1 |C| | |x| | |
Support of postmaster@domain |4.1.2 |C|x| | | | |
Support of loopback@domain |4.1.2 |C| |x| | | |
Support of distribution lists |4.1.3 |C| |x| | | |
| | | | | | | |
Message Header Fields: | | | | | | | |
Encoding outbound messages | | | | | | | |
From |4.2.1 |C|x| | | | |
Addition of text name |4.2.1 |C| |x| | | |
To |4.2.2 |C|x| | | | |1
cc |4.2.3 |C| |x| | | |1
Date |4.2.4 |C|x| | | | |
Sender |4.2.5 |C| | | |x| |
Message-id |4.2.6 |C|x| | | | |
Received |4.2.7 |C|x| | | | |
MIME Version: 1.0 (Voice 2.0) |4.2.8 |C|x| | | | |
Content-Type |4.2.9 |C|x| | | | |
Content-Transfer-Encoding |4.2.10 |C|x| | | | |
Sensitivity |4.2.11 |C| | |x| | |
Importance |4.2.12 |C| | |x| | |
Subject |4.2.13 |C| |x| | | |
| | | | | | | |
Detection & Decoding inbound messages | | | | | | | |
From |4.2.1 |C|x| | | | |
Utilize text personal name |4.2.1 |C| |x| | | |
To |4.2.2 |C|x| | | | |
cc |4.2.3 |C| | |x| | |
Date |4.2.4 |C|x| | | | |
Conversion of Date to local time |4.2.4 |C| |x| | | |
Sender |4.2.5 |C| | | |x| |
Message ID |4.2.6 |C|x| | | | |
Received |4.2.7 |C| | |x| | |
MIME Version: 1.0 (Voice 2.0) |4.2.8 |C|x| | | | |
Content Type |4.2.9 |C|x| | | | |
Content-Transfer-Encoding |4.2.10 |C|x| | | | |
Sensitivity |4.2.11 |C|x| | | | |2
Importance |4.2.12 |C| | |x| | |
Subject |4.2.13 |C| | |x| | |
Vaudreuil, Parsons Expires 3/9/97 [Page 31]
Internet Draft VPIM v2 September 9, 1996
Message Content Encoding: | | | | | | | |
Encoding outbound audio/fax contents | | | | | | | |
7BITMIME |4.3 |C| | | | |x|
8BITMIME |4.3 |C| | | | |x|
Quoted Printable |4.3 |C| | | | |x|
Base64 |4.3 |C|x| | | | |3
Binary |4.3 |C| |x| | | |4
Detection & decoding inbound messages | | | | | | | |
7BITMIME |4.3 |C|x| | | | |
8BITMIME |4.3 |C|x| | | | |
Quoted Printable |4.3 |C|x| | | | |
Base64 |4.3 |C|x| | | | |
Binary |4.3 |C|x| | | | |4
| | | | | | | |
Message Content Types: | | | | | | | |
Inclusion in outbound messages | | | | | | | |
Text/plain |4.3.1 |C| | | |x| |
Multipart/Mixed |4.3.2 |C| |x| | | |
Content-Description |4.3.2.1 |C| |x| | | |5
Message/RFC822 |4.3.3 |C| | |x| | |
Application/Directory |4.3.4 |C| |x| | | |
Audio/32KADPCM |4.3.5 |C|x| | | | |
Content-Description |4.3.5.1 |C| |x| | | |5
Content-Duration |4.3.5.2 |C| | |x| | |
Content-Langauge |4.3.5.3 |C| | |x| | |
Audio/* (other encodings) |4.3.6 |C| | |x| | |
Image/TIFF |4.3.7 |C|x| | | | |
Multipart/Report |4.3.8 |N|x| | | | |
Message/Notification |4.3.9 |N|x| | | | |
Message/Disposition-notification |4.3.10 |N|x| | | | |
Detection & decoding in inbound messages | | | | | | | |
Text/plain |4.3.1 |C|x| | | | |6
Multipart/Mixed |4.3.2 |C|x| | | | |
Content-Description |4.3.2.1 |C| | |x| | |
Message/RFC822 |4.3.3 |C|x| | | | |
Application/Directory |4.3.4 |C| |x| | | |
Audio/32KADPCM |4.3.5 |C|x| | | | |
Content-Description |4.3.5.1 |C| |x| | | |
Content-Duration |4.3.5.2 |C| | |x| | |
Content-Langauge |4.3.5.3 |C| | |x| | |
Audio/* (other encodings) |4.3.6 |C| | |x| | |
Image/TIFF |4.3.7 |C|x| | | | |6
Multipart/Report |4.3.8 |N|x| | | | |
Message/Notification |4.3.9 |N|x| | | | |
Message/Disposition-notification |4.3.10 |N|x| | | | |
Forwarded Messages | | | | | | | |
use Message/RFC822 construct |4.4 |C| |x| | | |
simulate headers if none available |4.4 |C| |x| | | |
Vaudreuil, Parsons Expires 3/9/97 [Page 32]
Internet Draft VPIM v2 September 9, 1996
| | | | | | | |
Message Transport Protocol: | | | | | | | |
ESMTP Commands | | | | | | | |
HELO |5.1.1 |T|x| | | | |
MAIL FROM |5.1.2 |T|x| | | | |
RCPT TO |5.1.3 |T|x| | | | |
DATA |5.1.4 |T|x| | | | |
TURN |5.1.5 |T| | | | |x|
QUIT |5.1.6 |T|x| | | | |
RSET |5.1.7 |T|x| | | | |
VRFY |5.1.8 |T| | |x| | |
EHLO |5.1.9 |T|x| | | | |
BDAT |5.1.10 |T| |x| | | |4
ESMTP Keywords & Parameters | | | | | | | |
PIPELINING |5.2.1 |T| |x| | | |
SIZE |5.2.2 |T|x| | | | |
CHUNKING |5.2.3 |T| |x| | | |
BINARYMIME |5.2.4,5.3.1|T| |x| | | |
NOTIFY |5.2.5,5.4.1|N|x| | | | |
ENHANCEDSTATUSCODES |5.2.6 |T| |x| | | |
RET |5.4.2 |N| |x| | | |
ESMTP-SMTP Downgrading | | | | | | | |
send delivery report upon downgrade |5.5 |N|x| | | | |
| | | | | | | |
Directory Address Resolution | | | | | | | |
provide facility to resolve addresses |6 |C| |x| | | |
use Vcards to populate local directory |6 |C|x| | | | |
use headers to populate local directory |6 |C| | | |x| |
| | | | | | | |
Management Protocols: | | | | | | | |
Network management |8.1 |T| |x| | | |
-------------------------------------------|----------|-|-|-|-|-|-|-
1. MUST NOT include if all recipients are not known or resolvable.
2. If a sensitive message is received by a system that does not
support sensitivity, then it MUST be returned to the originator
with an appropriate error notification. Also, a received
sensitive message MUST NOT be forwarded to anyone.
3. When binary transport is not available
4. When binary transport is available
5. If multiple contents are present in a message, this header MUST be
present
6. If the content cannot be presented in some form, the entire
message MUST be non-delivered.
Vaudreuil, Parsons Expires 3/9/97 [Page 33]
Internet Draft VPIM v2 September 9, 1996
15. Appendix B - Example Voice Messages
The following message is a full-featured, all-options-enabled message
addressed to two recipients. The message includes the sender's spoken
name and a short speech segment. The message is marked as important
and private.
To: 2145551212@vm1.mycompany.com
To: 2145551234@VM1.mycompany.com
From: "Vaudreuil, Greg" <2175552345@VM2.mycompany.com>
Date: Mon, 26 Aug 93 10:20:20 CST
MIME-Version: 1.0 (Voice 2.0)
Content-type: Multipart/Mixed; Boundary="MessageBoundary"
Content-Transfer-Encoding: 7bit
Message-ID: VM2.mycompany.com-123456789
Sensitivity: Private
Importance: High
--MessageBoundary
Content-type: Audio/32KADPCM
Content-Transfer-Encoding: Base64
Content-Description: Originator Spoken Name
Content-Language: EN-US
Content-ID: part1@VM2-4321
glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadasssdasddasdasd
(This is a sample of the base-64 Spoken Name data) fgdhgd
dlkgpokpeowrit09==
--MessageBoundary
Content-type: Audio/32KADPCM
Content-Transfer-Encoding: Base64
Content-Description: VPIM Message
Content-Duration: 25 seconds
iIiIiIjMzN3czdze3s7d7fwfHhcvESJVe/4yEhLz8/FOQjVFRERCESL/zqrq
(This is a sample of the base64 message data) zb8tFdLTQt1PXj
u7wjOyRhws+krdns7Rju0t4tLF7cE0K0MxOTOnRW/Pn30c8uHi9==
--MessageBoundary
Content-type: Application/Directory
Content-Transfer-Encoding: 7bit
BEGIN: Vcard
N: Vaudreuil;Greg;;Mr.;
EMAIL;TYPE=INTERNET: 2175552345@VM2.mycompany.com
TEL: +1-217-555-2345
SOUND;TYPE=32KADPCM;ENCODE=BASE64;VALUE=CID: <part1@VM2-4321>
REV: 19951031T222710Z
END: Vcard
--MessageBoundary--
Vaudreuil, Parsons Expires 3/9/97 [Page 34]
Internet Draft VPIM v2 September 9, 1996
The following message is a forwarded single segment voice.
To: 2145551212@vm1.mycompany.com
From: "Vaudreuil, Greg" <2175552345@VM2.mycompany.com>
Date: Mon, 26 Aug 93 10:20:20 CST
MIME-Version: 1.0 (Voice 2.0)
Content-type: Multipart/Mixed; Boundary="MessageBoundary"
Content-Transfer-Encoding: 7bit
Message-ID: VM2.mycompany.com-123456789
--MessageBoundary
Content-type: Audio/32KADPCM
Content-Description: VPIM Message
Content-Transfer-Encoding: Base64
glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadasssdasddasdasd
(This is the voiced introductory remarks encoded in base64)
jrgoij3o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90gQ5tkjpokfgW
dlkgpokpeowrit09==
--MessageBoundary
Content-type: Message/RFC822
Content-Transfer-Encoding: 7bit
To: 2175552345@VM2.mycompany.com
From: "Parsons, Glenn, W." <2145551234@VM1.mycompany.com>
From: Date: Mon, 26 Aug 93 8:23:10 EST
MIME-Version: 1.0 (Voice 2.0)
Content-type: Audio/32KADPCM
Content-Description: VPIM Message
Content-Transfer-Encoding: Base64
glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadasssdasddasdasd
(This is the original message audio data) fgwersdfmniwrjj
jrgoij3o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90gQ5tkjpokfgW
dlkgpokpeowrit09==
--MessageBoundary
Content-type: Application/Directory
Content-Transfer-Encoding: 7bit
BEGIN: Vcard
N: Vaudreuil;Greg;;Mr.;
SOUND;TYPE=32kbADPCM;ENCODE=BASE64;VALUE=INLINE:
glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadasssdasddasdasd
(This is the Spoken Name audio data) fgwersdfmniwrjjedfsa
jrgoij3o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90gQ5tkjpokfgW
dlkgpokpeowrit09==
REV: 19951031T222710Z
END: Vcard
--MessageBoundary-
Vaudreuil, Parsons Expires 3/9/97 [Page 35]
Internet Draft VPIM v2 September 9, 1996
The following example is for a message returned to the sender by a
VPIM gateway at VM1.company.com for a mailbox which does not exist.
Date: Thu, 7 Jul 1994 17:16:05 -0400
From: Mail Delivery Subsystem <MAILER-DAEMON@vm.company.com>
Message-Id: <199407072116.RAA14128@vm1.company.com>
Subject: Returned voice message
To: 2175552345@VM2.mycompany.com
MIME-Version: 1.0 (Voice 2.0)
Content-Type: multipart/report; report-type=delivery-status;
boundary="RAA14128.773615765/VM1.COMPANY.COM"
--RAA14128.773615765/VM1.COMPANY.COM
Content-type: Audio/32KADPCM
Content-Transfer-Encoding: Base64
glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadadffsssddasdasd
(This is a voiced description of the error in base64)
jrgoij3o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90gdffkjpokfgW
dlkgpokpeowrit09==
--RAA14128.773615765/VM1.COMPANY.COM
content-type: message/delivery-status
Reporting-MTA: dns; vm1.company.com
Original-Recipient: rfc822; 2145551234@VM1.mycompany.com
Final-Recipient: rfc822; 2145551234@VM1.mycompany.com
Action: failed
Status: 5.1.1
Diagnostic-Code: smtp; 550 Mailbox not found
Last-Attempt-Date: Thu, 7 Jul 1994 17:15:49 -0400
--RAA14128.773615765/VM1.COMPANY.COM
content-type: message/rfc822
[original VPIM message goes here]
--RAA14128.773615765/VM1.COMPANY.COM--
Vaudreuil, Parsons Expires 3/9/97 [Page 36]
Internet Draft VPIM v2 September 9, 1996
16. Appendix C - Example Error Voice Processing Error Codes
Error condition
RFC 1893 Error codes and recommended comments
Analog delivery failed because remote system is busy
4.4.0 Persistent connection - other
Analog delivery failed because remote system is ring-no-answer
4.4.1 Persistent protocol - no answer from host
Remote system did not answer "D" in response to "C" at connect time
5.5.5 Permanent protocol - wrong version
Mailbox does not exist
5.1.1 Permanent mailbox - does not exist
Mailbox full or over quota
4.2.2 Persistent mailbox - is full
Disk full
4.3.1 Persistent system - is full
Command out of sequence
5.5.1 Permanent protocol - error
Frame Error
5.5.2 Permanent protocol - syntax error
Mailbox does not support FAX
5.6.1 Permanent media - not capable
Mailbox does not support TEXT
5.6.1 Permanent media - not capable
Sender is not authorized
5.7.1 Permanent security - sender not authorized
Message marked private, but system is not private capable
5.3.3 Permanent system - not private capable
Vaudreuil, Parsons Expires 3/9/97 [Page 37]
Internet Draft VPIM v2 September 9, 1996
17. Appendix D - audio/32KADPCM Content Type
Mime type name: audio
Mime Sub-Type name: 32KADPCM
Required Parameters: None
Optional Parameters: None
Encoding Considerations: Any encoding necessary for transport may be
used.
ITU-T Recommendation G.726 [G726] (was G.721) describes the algorithm
recommended for conversion of a single 64 kbit/s A-law or mu-law PCM
channel encoded at 8000 samples/sec to and from a 32 kbit/s channel.
The conversion is applied to the PCM stream using an Adaptive
Differential Pulse Code Modulation (ADPCM) transcoding technique.
No header information shall be included as part of the audio data.
The 4-bit code words of the G.726 encoding MUST be packed into
octets/bytes as follows: the first code word is placed in the four
least significant bits of the first octet, with the least significant
bit of the code word in the least significant bit of the octet; the
second code word is placed in the four most significant bits of the
first octet, with the most significant bit of the code word in the
most significant bit of the octet. Subsequent pairs of the code words
shall be packed in the same way into successive octets, with the first
code word of each pair placed in the least significant four bits of
the octet. It is prefered that the voice sample be extended with
silence such that the encoded value comprises an even number of code
words. However, if the voice sample comprises an odd number of code
words, then the last code word shall be discarded.
In the context of VPIM, the Content-Description header SHOULD be used
to describe the contents of the audio body. The header must be able
to be parsed to find these identifiying phrases: Voice Message,
Originator Spoken Name, Recipient Spoken Name, or Spoken Subject.
Other headers may be used with their defined semantics.
Vaudreuil, Parsons Expires 3/9/97 [Page 38]
Internet Draft VPIM v2 September 9, 1996
18. Appendix E - image/TIFF Content Type
Mime type name: image
Mime Sub-Type name: TIFF
Required Parameters: None
Optional Parameters: None
Encoding Considerations: Any encoding necessary for transport may be
used.
18.1 References
TIFF (Tag Image File Format) is defined in:
TIFF (TM) Revision 6.0 - Final -
Adobe Developers Association
Adobe Systems Incorporated
1585 Charleston Road
P.O. Box 7900 Mountain View, CA 94039-7900
A copy of this specification can be found in:
ftp://ftp.adobe.com/pub/adobe/DeveloperSupport/TechNotes/PDFfiles
TIFF Class F has previously never been documented in a detailed
fashion. However, it is clearly defined in Section 10.7.4 Spatial
Media of:
Enterprise Computer Telephony Forum
S.100 Revision 1.0
Media Services "C" Language
Application Programming Interfaces
THE ECT Forum
303 Vintage Park Drive
Foster City, CA 94404-1138
A copy of this specification can be found in:
http://www.ectf.org/ectf_s100.html
18.2 TIFF Class F
The essential parts of the ECTF S.100 definition are repeated here:
The default TIFF tags which apply for reading (sending) and writing
(receiving) are described in the sections below entitled TIFF Reader
and TIFF Writer. The TIFF requirements below are broken into two
sections, specifying the requirements for all TIFF reader
implementations (Used for sending a FAX) and TIFF writer
implementations (Used to receive a fax) that will be supported for
use.
Vaudreuil, Parsons Expires 3/9/97 [Page 39]
Internet Draft VPIM v2 September 9, 1996
18.2.1 TIFF Reader
All implementations must be able to read (send) TIFF files meeting the
requirements below. Image data must not have any coding errors.
Implementations may also read any other formats as long as available
formats can be disclosed to applications at run time.
ByteOrder: MM,II (Either byte order is allowed)
These tags shown below must be readable. If not present, reader must
use default shown:
TIFF Reader Tags
Tag | Legal | Default |Comment
------------------|-------------|--------------|----------------------
BitsPerSample | 1 | 1 |one bit per sample
CleanFaxData | 0 | 0 |data has no errors
Compression | 3 | 3 |T.4 bi-level encoding,
| | | MH
FillOrder | 2,1 | 2 |LSB first or MSB first
ImageWidth | 1728 | 1728 |
ImageLength | >0 | |required
NewSubFileType | 2 | 2 |single page of
| | |multipage file
Orientation | 1 | 1 |1st row=top left,
| | | 1st col=top
PageNumber | X/X | 0/1 |pg/tot, 0 base,
| | | tot in 1st IFD
PhotometricInterp | 0 | 0 |0 is white
ResolutionUnit | 2 | 2 |inches
RowsPerStrip |=ImageLength |=ImageLength |
SamplesPerPixel | 1 | 1 |one sample per pixel
StripByteCounts | >0 | |required
StripOffsets | >0 | |required
T4Options | 4 | 4 |MH, byte aligned EOL
Xresolution | 204,200,77 | 204 |
Yresolution | 196,98,100, | 196 |
| 200,77,38.5 | |
------------------|-------------|--------------|----------------------
Other tags may be present, but must be of the sort that can be ignored
safely by implementations (i.e. purely informational).
Vaudreuil, Parsons Expires 3/9/97 [Page 40]
Internet Draft VPIM v2 September 9, 1996
18.2.2 TIFF Writer
For fax writing (receiving), implementations are required to use the
following TIFF format as a default. Image data must not have any
coding errors. Implementations may write other formats as long as
applications have selected from among those formats at run time.
TIFF Writer Tags
Tag | Legal Values | Comment
------------------|----------------|----------------------------------
ByteOrder | II |
BitsPerSample | 1 | one bit per sample
Compression | 3 | T.4 bi-level encoding, MH
FillOrder | 2 | LSB first
ImageWidth | 1728 |
ImageLength | > 0 |
NewSubFileType | 2 | single page of multi-page file
PageNumber | X/X | pg/tot, 0 base, tot in 1st IFD
PhotometricInterp | 0 | 0 is white
ResolutionUnit | 2 | inches
RowsPerStrip | >0 | must be same as ImageLength
SamplesPerPixel | 1 | one sample per pixel
StripByteCounts | >0 | as appropriate
StripOffsets | >0 | as appropriate
T4Options | 4 | MH, byte aligned EOL
Xresolution | 204,200,77 |
Yresolution | 196,98,100, |
| 200,77,38.5 |
------------------|----------------|----------------------------------
Tags that are optional, but if present must contain the values as
shown:
Optional TIFF Writer Tags
Tag | Legal Values | Comment
----------------|----------------|------------------------------------
CleanFaxData | 0 | data doesn't contain bad scan lines
Orientation | 1 | 1st row = top left, 1st col = top
----------------|----------------|------------------------------------
Other tags may be present, but must be of the sort that can be ignored
safely by applications (i.e. purely for information).
Recommended informational tags are:
Software, Datetime, BadFaxLines, ConsecutiveBadFaxLines
Vaudreuil, Parsons Expires 3/9/97 [Page 41]
Internet Draft VPIM v2 September 9, 1996
19. Appendix F - Change History: RFC 1911 to this Document
This update is based on the experience of a proof of concept
demonstration of VPIM at EMA'96 in April 1996. This version of the
profile is significantly different from the previous. These changes
are detailed below:
1. General
- Various editorial updates to improve readability
- Changed the Voice version to 2.0
- Added Table of Contents and more examples
- Refined audio/32KADPCM (nibble order) and image/TIFF (tag defaults)
definitions
2. Content
- Deprecated multipart/voice-message content because of the removal of
positional dependence of contents and the desire to interoperate with
minimal MIME implementationsde
- Explicitly defined the forwarding model using message/RFC822
- Eliminated the text name in the "To" and "CC" headers. Edited the
conformance to require last-name, first-name only for persons
- Described handling of private messages
- Profiled the Vcard in the application/directory body part for
transport of directory information on the originator
- Added support for facsimile using the refined image/TIFF content
- Loosened text restriction
- Added suggested addressing formats
- Added additional details on delivery notifications
3. Transport
- Moved Binary support to optional
- Added ESMTP keyword for Return of Status codes
4. Compliance
- Added an explicit section on conformance allowing conformance to all
or any of three conformance areas
- Improved conformance table
Vaudreuil, Parsons Expires 3/9/97 [Page 42]
Internet Draft VPIM v2 September 9, 1996
20. Appendix G -- Open Issues
1) Finalize changes appendix
2) Sufficient examples
3) Must date be included at an AMIS to VPIM gateway?
Vaudreuil, Parsons Expires 3/9/97 [Page 43]