Virtualized Conversations R. Mahy
Internet-Draft Rohan Mahy Consulting Services
Intended status: Informational 24 February 2025
Expires: 28 August 2025
VCON for MIMI Messages
draft-mahy-vcon-mimi-messages-02
Abstract
This document describes extensions to the Virtualized Conversation
(VCON) syntax for instant messaging systems using the More Instant
Messaging Interoperability (MIMI) content format.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at
https://rohanmahy.github.io/vcon-mimi-messages/draft-mahy-vcon-mimi-
messages.html. Status information for this document may be found at
https://datatracker.ietf.org/doc/draft-mahy-vcon-mimi-messages/.
Discussion of this document takes place on the Virtualized
Conversations Working Group mailing list (mailto:vcon@ietf.org),
which is archived at https://mailarchive.ietf.org/arch/browse/vcon/.
Subscribe at https://www.ietf.org/mailman/listinfo/vcon/.
Source for this draft and an issue tracker can be found at
https://github.com/rohanmahy/vcon-mimi-messages.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 28 August 2025.
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Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3
3. Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Room information . . . . . . . . . . . . . . . . . . . . 4
3.2. Parties . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.3. The dialog object (text type) . . . . . . . . . . . . . . 5
3.3.1. Semantics of the existing fields for text . . . . . . 5
3.3.2. Extensions to the dialog object for text . . . . . . 5
3.3.3. MultiPart objects . . . . . . . . . . . . . . . . . . 6
3.3.4. Part objects . . . . . . . . . . . . . . . . . . . . 6
3.3.5. ExternalPart objects . . . . . . . . . . . . . . . . 7
3.4. Changes to the parties . . . . . . . . . . . . . . . . . 8
3.5. Changes to the room . . . . . . . . . . . . . . . . . . . 9
3.6. Attachments . . . . . . . . . . . . . . . . . . . . . . . 9
3.7. Message tombstones . . . . . . . . . . . . . . . . . . . 9
4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1. MIMI examples as a VCON . . . . . . . . . . . . . . . . . 10
4.2. MIMI VCON with an Attachment . . . . . . . . . . . . . . 16
5. Security Considerations . . . . . . . . . . . . . . . . . . . 17
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
7. Normative References . . . . . . . . . . . . . . . . . . . . 17
Appendix A. CDDL changes . . . . . . . . . . . . . . . . . . . . 18
Appendix B. Change list . . . . . . . . . . . . . . . . . . . . 18
B.1. Changes in draft-mahy-vcon-mimi-messages-02 . . . . . . . 19
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 19
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
VCON [I-D.ietf-vcon-vcon-container] is a format for recording and
transmitting conversations. MIMI content [I-D.ietf-mimi-content] is
a format for conveying Instant Messages in an interoperable way when
end-to-end encrypted. This document describes a way to translate a
set of MIMI messages in a conversation or part of a conversation into
a VCON.
2. Conventions and Definitions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The examples in this document may contain base64url encoded values
that have extra whitespace added for readability, and to conform with
Internet-Draft formatting conventions. That whitespace should be
ignored.
Some metadata about a MIMI content message is conveyed in the
encryption protocol Messaging Layer Security (MLS) [RFC9420] or in
the MIMI protocol [I-D.ietf-mimi-protocol].
For example, the sender, recipient, date, and message ID are not
mandatory fields in a MIMI content message. The recipient is the
MIMI room ID associated with the corresponding MLS group. The
participants in the group are calculated from the MLS group state and
MIMI participant list during the MLS "epoch" in which the message was
sent. The sender is conveyed in MLS. The MIMI "Hub" received
timestamp is conveyed in the MIMI protocol. The MIMI content message
ID is constructed by hashing fields from the MIMI content, and the
sender and room URIs (see Section 3.3 of [I-D.ietf-mimi-content]).
When message franking is enabled, as defined in Section 5.4.1 of
[I-D.ietf-mimi-protocol], the franking_tag is conveyed in the MLS
message's Additional Authenticated Data (AAD) field, while the MIMI
protocol conveys the Frank structure generated by the MIMI Hub.
The room metadata described in this document comes from Section 3 of
[I-D.mahy-mimi-app-components], while the names of the parties comes
from the participant list defined in Section 4 of the same document.
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3. Syntax
A MIMI conversation (or portion thereof) is represented in VCON with
a mandatory list of parties and dialogs, a new top-level room object,
and optionally attachment objects.
3.1. Room information
This document adds a mandatory, top-level room object. It contains
metadata known about the room at the start of the VCON period.
* id is the MIMI room ID URL. It is mandatory.
* name is the textual name of the room. It is optional.
* avatar is a URL referencing the room image. It is optional.
* subject is the room subject. It is optional.
* mood is the room mood. It is optional
* description is an array of room_description objects. It is
optional. Each object can contain:
- a type- a media type or an empty string. It is optional. It's
default value is text/plain;charset=UTF-8.
- a lang - a Language-tag as defined by [RFC5646]. It is
optional.
- a content - if the type begins with "text" or is empty, the
content the is UTF-8 text description of the room. Otherwise
it is the base64url encoding of whatever type is described.
The content field is mandatory in a room_description object.
3.2. Parties
The parties array MUST contain all the participants who were in the
conversation at any point in time during the period represented by
the VCON. The first party in the array is the MIMI room URI.
This document adds a new party_object_type: im_uri. It is mandatory.
The name field is optional. The role indicates the MIMI role and is
optional. The document also adds a thumbprint party_object_type,
which is the JWK thumbprint of the public key of the party. If there
are multiple parties (clients) with the same im_uri then the
thumbprint is required, otherwise it is optional.
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3.3. The dialog object (text type)
The following section refers to changes and additions to the dialog
object when the type field is "text".
3.3.1. Semantics of the existing fields for text
The dialog object consists of an array of instant messages of type
"text". The start time is set to the hub received timestamp when
available. The duration is zero. The originator is set to the
parties index of the sender of the message.
The first MIMI message represented in a MIMI VCON should contain the
complete list of parties who were participants in the room at that
time. For subsequent messages, a parties array consisting of index
zero, indicates the recipients of the message are the active
participants of the room. Changes to the roster can be tracked if
party_history is present for those changes (see Section 3.4).
3.3.2. Extensions to the dialog object for text
The parties array consist of the party indexes of those who were
active participants when the message was sent.
* message_id is the base64url encoding of the MIMI content message
ID. It is mandatory.
* salt is the base64url encoding of the MIMI content salt. It is
mandatory.
* replaces is the base64url encoding of the MIMI content message_id
of the message this message replaces. It is optional if empty.
* topic_id is the base64url encoding of the MIMI topic_id. It is
optional if empty.
* expires is optional if empty in MIMI. It contains null or a map
with the following items:
- relative is a boolean that is true if the time is expressed
relative to the recipient read time, and false if it is
expressed as an absolute date/time. It is mandatory when
expires is present.
- relative_time is an integer number of seconds. If relative is
true, once the message has been read, the client is expected to
delete the message after relative_time seconds. It is
mandatory if relative is true.
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- absolute_time is the expiration date/time of the message
expressed as a VCON (text) date_type. It is mandatory if
relative is false and optional otherwise.
* in_reply_to is the base64url encoding of the MIMI content
message_id of the message to which this message is replying (or
reacting). It is optional if empty.
* mimi_extensions is a base64 encoding of the CBOR MIMI content
extensions map or null. It is optional if not present in the MIMI
content.
* franking_tag is a base64url encoding of the MIMI franking_tag, or
null. It is optional if not present.
* frank is a base64url encoding of the MIMI protocol Frank TLS
struct, or null. It is optional if not present.
VCON typically expresses message content using the body, encoding,
and mediatype fields. In order to preserve this convention we use
these fields directly for a MIMI SinglePart structure, but use new
MultiPart and ExternalPart objects for those corresponding MIMI
structures. For a SinglePart these two fields with the same
semantics as their MIMI content counterparts could be present.
* disposition - optional if set to the default value ("render")
* language - optional if absent
If there is only a single part its part_index is 0, and in this case
it is optional.
3.3.3. MultiPart objects
A MultiPart object is designed to carry multiple items, as with the
MultiPart structure in MIMI content or the top level multipart media
types. It contains the following fields.
* part_semantics is one of "chooseOne", "singleUnit", or
"processAll". It is mandatory.
* parts is an array of Parts. It is mandatory in a MultiPart
object.
3.3.4. Part objects
The following fields can be in a Part object. They have the same
meaning as their MIMI content counterparts.
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* disposition optional if set to the default value ("render")
* language - optional if absent
* part_index is an unsigned integer. It is mandatory in a Part
object.
* cardinality is one of "nullpart", "single", "external", or
"multi". mandatory.
If cardinality is "single" or "external", then body, encoding, and
mediatype fields are included directly in the Part object.
3.3.5. ExternalPart objects
The ExternalPart object can contain the following fields with similar
meanings to those in MIMI content, with exceptions noted below.
* mediatype is the value of the contentType in MIMI. It is
mandatory if present in the MIMI message and recommended
otherwise.
* url is the URL of the content as a text string. It is mandatory
* expires is a date_type (text) date. It is optional if not
present.
* size is an integer number of octets. It is optional if not
present.
* description is a text string. It is optional if not present.
* filename is a text string. It is optional if not present.
* content_hash is the base64url encoded string of the MIMI
contentHash of the ExternalPart, prefixed with the name of the
hash algorithm corresponding to hashAlg and a colon (for example
"sha256:"). content_hash is mandatory if it was included in the
MIMI content ExternalPart, and omitted otherwise.
In addition, the following fields are unique to MIMI VCON.
* cached is a boolean. It is mandatory if it is true, which means
that a copy of the external content is available in a vcon
attachment object (see Section 3.6). If cache is true and no
content_hash is present, a new content hash is calculated for the
attachment and placed the cache_ref field (which can only be
present in this case).
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ExternalPart has several fields for the decryption of the referenced
content. If it is not necessary to reconstruct the original MIMI
content (for example to allow later verification of the message ID),
these fields can be omitted once the content has been downloaded,
decrypted, verified, and included in the VCON attachments array.
Otherwise they are mandatory if present in the MIMI content. All of
these fields are base64url encoded strings.
* encAlg
* key
* nonce
* aad
3.4. Changes to the parties
The party_history object can be interleaved with text objects in the
dialog objects array. It indicates when changes have been made to
the participants represented by party index zero, as well as
properties of individual parties (such as their role or name).
The party_history object contains the following fields.
* party is the party index of the modified party. It is mandatory.
* originator is the party that originated the change. It is
optional.
* time is the time that the change was effected
* event is the type of change. It is mandatory and for MIMI VCONs
can be one of the following new event types:
- add: user added by someone else
- self_add: user added herself directly
- leave: user leaves of their own accord
- remove: user is removed by another user
- ban: user is banned from the group
- update:
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* name is the new name of the user. It is only permitted for an
update event.
* role is the new role assigned to the user. It is only permitted
for an update event.
3.5. Changes to the room
Changes to the room metadata should be accompanied by a new room
dialog type. The room dialog type can contain anything in the top-
level room object except for the id (which cannot change). It must
contain a time field to convey the time of the change, and may
contain an originator field to convey who made that change.
3.6. Attachments
An attachment consists of the following fields:
* start: is the time when the attachment was downloaded. It is
mandatory.
* party: is the party that downloaded the attachment. It is
mandatory.
* content_hash: is the base64url encoded hash using the hash name
prefixed with a colon before the hash (ex: "sha256:"). It is
mandatory.
* dialog_object_ref is a string consisting of: "mid:" (representing
the message ID URI), the message_id of the message in the dialog
object, a colon, the part_index of the Part (or "0" if the
ExternalPart is at the top level), and the string "@anon.invalid"
The mediatype, filename, encoding, and body fields are as they are
defined in VCON and are all mandatory.
3.7. Message tombstones
When a message has been deleted/retracted, or it expires, it can be
valuable to present a record that such a message was previously
present, by generating a dialog object with the following fields
(which are all mandatory):
* type is "tombstone"
* start is the time the tombstone was generated
* message_id is the message ID of the message.
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* status is the status of the former message, either "retracted" or
"expired".
4. Examples
4.1. MIMI examples as a VCON
The example vcon consists of the example messages from Section 5 of
the MIMI content specification plus a party_history object adding two
new participants, and a single multipart message at the end.
{
"vcon": "0.0.1",
"room": {
"id": "mimi://example.com/r/engineering_team",
"name": "Engineering Team",
"avatar": "https://example.com/images/tHMqLMAkmCzNmweL",
"subject": None,
"mood": None,
"description": [
{"type":"", "lang":"en", "content":"Engineering Team Internal Chat"},
{ "type":"",
"lang":"fr",
"content":"Chat de l'équipe interne des ingénieurs"
}
]
}
"parties": [
{
"imUri": "mimi://example.com/r/engineering_team",
},
{
"im_uri": "mimi://example.com/u/alice-smith",
"name": "Alice Smith",
"role": "moderator",
"thumbprint": "TODOFIXDZXCog_FfQp-xLemZkD5GKB9H7Z-Y41O4jEw"
},
{
"im_uri": "mimi://example.com/u/bob-jones",
"name": "Bob Jones",
"role": "member",
"thumbprint": "TODOFIXYUFE7bV9pXAHZHi5bwSWzLJqjncevs9aLKDg"
},
{
"im_uri": "mimi://example.com/u/cathy-washington",
"name": "Cathy Washington",
"role": "member",
"thumbprint": "TODOFIXzH3EeOGbI0-oiDGTXlgKmkMzQyQ2W_Y-TB1U"
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},
{
"im_uri": "mimi://example.com/u/doug-king",
"name": "Doug King",
"role": "member",
"thumbprint": "TODOFIX3fdpORnHwncbdOS5XieH-z1m5r61u14WyNkj"
},
{
"im_uri": "mimi://example.com/u/liz-roberts",
"name": "Elizabeth Roberts",
"role": "member",
"thumbprint": "TODOFIX7qR7oFriyKfKgIJ43ZdANoObICqH0kN9g82J"
}
],
"dialog": [
{
"type": "text",
"start": "2022-02-08T22:13:45.019-00:00",
"duration": 0,
"parties": [
1, 2, 3
],
"franking_tag": null,
"frank": null,
"originator": 1,
"salt": "PC16IkqDbGRiffzjeyPKIg"
"message_id": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ",
"mimi_extensions": "oQGiAXgrbWltaTovL2h1Yi5leGFtcGxlL3IvU
mwzM0ZXTENZV093eEhyWW5wV0RRZwJ4GG1pbWk6Ly9iLmV4YW1wbG
UvdS9hbGljZQ",
"mimetype": "text/markdown;variant=GFM",
"encoding": "none"
"body":
"Hi everyone, we just shipped release 2.0. __Good work__!",
},
{
"type": "text",
"start": "2022-02-08T22:13:57.492-00:00",
"duration": 0,
"parties": [
0
],
"originator": 2,
"salt": "PVeWNQrjJej4AjhqkGlSkw"
"message_id": "Ygye96VUeBhTO6U3D0ZllYsSwSdKB3SiRJgxAb3cdAo",
"in_reply_to": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ",
"mimetype": "text/markdown;variant=GFM",
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"encoding": "none"
"body": "Right on! _Congratulations_ \'all!",
},
{
"type": "text",
"start": "2022-02-08T22:13:57.728-00:00",
"duration": 0,
"parties": [
0
],
"originator": 3,
"salt": "lV7CoeiFmX4ALPSKOdrR0w"
"message_id": "2YF0k6blW9ZbJ8sgXJgMCTJOlofazdKwVRvf6ZUORFA",
"in_reply_to": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ",
"disposition": "reaction",
"mimetype": "text/plain;charset=utf-8",
"encoding": "none"
"body": "❤",
},
{
"type": "text",
"start": "2022-02-08T22:14:03.008-00:00",
"duration": 0,
"parties": [
0
],
"originator": 3,
"salt": "pkL5Tr0pLla5EiLUOfVDJw"
"message_id": "rF4iS5BcJ-aFfisoFDCrnTE9pZZBGCxGCoXGJ9VXnck",
"mimetype": "text/markdown;variant=GFM",
"encoding": "none"
"body":
"Kudos to [@Alice Smith](mimi://example.com/alice-smith) for
making the release happen!",
},
{
"type": "text",
"start": "2022-02-08T22:14:08.621-00:00",
"duration": 0,
"parties": [
0
],
"originator": 2,
"salt": "26QI8adeG9TDfPvh-j1Stg"
"message_id": "-GqJXuoaJu1Xosu-N8nt6NWzA2RLmIRY0q9jf_kvWkM",
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"replaces": "Ygye96VUeBhTO6U3D0ZllYsSwSdKB3SiRJgxAb3cdAo",
"in_reply_to": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ",
"mimetype": "text/markdown;variant=GFM",
"encoding": "none"
"body": "Right on! _Congratulations_ y'all"
},
{
"type": "text",
"start": "2022-02-08T22:14:08.621-00:00",
"duration": 0,
"parties": [
0
],
"originator": 2,
"salt": "HbkjCnTRrhn84LPT86VvYg"
"message_id": "8cqo1B9IA6nnB63oPEnmWxIqr7uk7WvQTBgVVlD_Q2c",
"replaces": "Ygye96VUeBhTO6U3D0ZllYsSwSdKB3SiRJgxAb3cdAo",
"in_reply_to": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ"
},
{
"party_history": [
{
"party": 4,
"event": "add",
"originator": 1,
"time": "2022-02-08T22:14:09.277-00:00"
},
{
"party": 5,
"event": "add",
"originator": 1,
"time": "2022-02-08T22:14:09.277-00:00"
}
]
},
{
"type": "text",
"start": "2022-02-08T22:14:10.389-00:00",
"duration": 0,
"parties": [
0
],
"originator": 3,
"salt": "IrAeojgZcZGiQjjBbmqVhw"
"message_id": "bYZ2NHaryq0WS2pq5IE9fMc4zltUyE6WrKJ7bNB5tMc",
"replaces": "Ygye96VUeBhTO6U3D0ZllYsSwSdKB3SiRJgxAb3cdAo",
"in_reply_to": "yjetjodyYNLBto8YDnwLkEc89W09rOuEivbnxKGfHLQ",
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"disposition": "reaction"
},
{
"type": "text",
"start": "2022-02-08T22:49:06.227-00:00",
"duration": 0,
"parties": [
0
],
"originator": 1,
"salt": "8xnQi9hjVw4N8cRGEm4X1A"
"message_id": "GkblzkXJxyar0lTgkfcMQ0wo8qpbcU0MqtTg-gM1FiY",
"expiring": {
"relative": false,
"expires": "2022-02-08T22:59:06.227-00:00"
},
"status": "expired"
},
{
"type": "text",
"start": "2022-02-08T22:53:41.134-00:00",
"duration": 0,
"parties": [
0
],
"originator": 2,
"salt": "bqhJBqYaTyDmgTj-QtdZPA"
"message_id": "Tdt8UCUl1ugSLRmuObvib_4bvu_Hz3NSwaYuy-TtET4",
"disposition": "attachment",
"language": "en",
"ExternalPart": {
"mimetype": "video/mp4",
"url": "https://example.com/storage/8ksB4bSrrRE.mp4",
"size": 708234961,
"description": "2 hours of key signing video",
"filename": "bigfile.mp4",
"content_hash":
"sha256:OczZYpW_L0B1DsMSLJqL2jTRJKoj7fTUJ2jhnX70-00",
"enc_alg": 1,
"key": "aZISOs306M7n_3csR-J1cw",
"nonce": "5VM0QcZI3PNmnquV6CUgxg",
"aad": ""
}
},
{
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"type": "text",
"start": "2022-02-08T22:54:09.972-00:00",
"duration": 0,
"parties": [
0
],
"originator": 3,
"salt": "dPEJAGOdZGeX6_OCp0RUzA"
"message_id": "KgDTc29ZP4YyYmXtaYyxpZNrnigjvCjrCYuLTz19zWc",
"disposition": "session",
"ExternalPart": {
"url": "https://example.com/join/12345",
"description": "Join the Foo 118 conference"
}
},
{
"type": "text",
"start": "2022-02-08T22:57:14.084-00:00",
"duration": 0,
"parties": [
0
],
"originator": 1,
"salt": "YSbs-8jeoXfI6Z4lQRUWQw"
"message_id": "sD19bKRmu4mA9SHznfQOLQQzKnx1Q4mEtSNQhvzqCZw",
"disposition": "render",
"part_index": 0,
"MultiPart": {
"part_semantics": "chooseOne",
"parts": [
"Part": {
"disposition": "render",
"language": "en",
"part_index": 1,
"mimetype": "text/markdown;variant=GFM",
"encoding": "none"
"body": "Hello!"
},
"Part": {
"disposition": "render",
"language": "fr",
"part_index": 2,
"mimetype": "text/markdown;variant=GFM",
"encoding": "none"
"body": "Bonjour!"
}
]
}
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},
]
}
4.2. MIMI VCON with an Attachment
This example vcon consists of a single message in a dialog which
references an attachment.
{
"vcon": "0.0.1",
"room": {
"id": "mimi://example.com/r/engineering_team",
"name": "Engineering Team",
}
"parties": [
{
"imUri": "mimi://example.com/r/engineering_team",
},
{
"im_uri": "mimi://example.com/u/alice-smith",
"name": "Alice Smith",
"role": "moderator",
"thumbprint": "TODOFIXDZXCog_FfQp-xLemZkD5GKB9H7Z-Y41O4jEw"
},
{
"im_uri": "mimi://example.com/u/bob-jones",
"name": "Bob Jones",
"role": "member",
"thumbprint": "TODOFIXYUFE7bV9pXAHZHi5bwSWzLJqjncevs9aLKDg"
},
{
"im_uri": "mimi://example.com/u/cathy-washington",
"name": "Cathy Washington",
"role": "member",
"thumbprint": "TODOFIXzH3EeOGbI0-oiDGTXlgKmkMzQyQ2W_Y-TB1U"
}
],
"dialog": [
{
"type": "text",
"start": "2022-02-08T22:53:41.134-00:00",
"duration": 0,
"parties": [
0, 1, 2, 3
],
"originator": 1,
"salt": "jaPfwAWReuvBdfayWkSvtQ"
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"message_id": "Tdt8UCUl1ugSLRmuObvib_4bvu_Hz3NSwaYuy-TtET4",
"disposition": "attachment",
"language": "en",
"ExternalPart": {
"mimetype": "video/mp4",
"url": "https://example.com/storage/8ksB4bSrrRE.mp4",
"size": 708234961,
"description": "2 hours of key signing video",
"filename": "bigfile.mp4",
"content_hash":
"sha256:OczZYpW_L0B1DsMSLJqL2jTRJKoj7fTUJ2jhnX70-00",
"cached": true
}
},
],
"attachments": [
{
"start": "2022-02-08T22:53:41.134-00:00",
"party": 1,
"content_hash":
"sha256:OczZYpW_L0B1DsMSLJqL2jTRJKoj7fTUJ2jhnX70-00",
"dialogObjectRef":
"mid:Tdt8UCUl1ugSLRmuObvib_4bvu_Hz3NSwaYuy-TtET4:0@anon.invalid",
"mimetype": "video/mp4",
"filename": "bigfile.mp4",
"encoding": "base64url",
"body": "Ma0hHSr0f_iUk_RSShTgtY...nSQbZEip5danJYQqsvwWQ"
}
]
}
5. Security Considerations
TODO Security
6. IANA Considerations
This document has no IANA actions.
7. Normative References
[I-D.ietf-mimi-content]
Mahy, R., "More Instant Messaging Interoperability (MIMI)
message content", Work in Progress, Internet-Draft, draft-
ietf-mimi-content-05, 20 December 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-mimi-
content-05>.
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[I-D.ietf-mimi-protocol]
Barnes, R., Hodgson, M., Kohbrok, K., Mahy, R., Ralston,
T., and R. Robert, "More Instant Messaging
Interoperability (MIMI) using HTTPS and MLS", Work in
Progress, Internet-Draft, draft-ietf-mimi-protocol-02, 21
October 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-mimi-protocol-02>.
[I-D.ietf-vcon-vcon-container]
Petrie, D. and T. McCarthy-Howe, "The JSON format for vCon
- Conversation Data Container", Work in Progress,
Internet-Draft, draft-ietf-vcon-vcon-container-01, 20
October 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-vcon-vcon-container-01>.
[I-D.mahy-mimi-app-components]
Mahy, R., "Application State Components for More Instant
Messaging Interoperability (MIMI)", Work in Progress,
Internet-Draft, draft-mahy-mimi-app-components-01, 11
February 2025, <https://datatracker.ietf.org/doc/html/
draft-mahy-mimi-app-components-01>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
September 2009, <https://www.rfc-editor.org/rfc/rfc5646>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC9420] Barnes, R., Beurdouche, B., Robert, R., Millican, J.,
Omara, E., and K. Cohn-Gordon, "The Messaging Layer
Security (MLS) Protocol", RFC 9420, DOI 10.17487/RFC9420,
July 2023, <https://www.rfc-editor.org/rfc/rfc9420>.
Appendix A. CDDL changes
*TODO*
Appendix B. Change list
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B.1. Changes in draft-mahy-vcon-mimi-messages-02
* adjust to make consistent with new syntax of MIMI content (add
salt, removed lastSeen, in_reply_to is just a message id, expires
is an object to handle relative expiration, added
mimi_extensions).
* use a different field from content_hash when attaching an
ExternalPart that did not have a hash in the MIMI message.
* allow the parties list of 0 to indicate sending to every active
participant in the room.
* added a description of using party_history to track changes to the
participant list.
* added room metadata, and a way to modify it
* added support for message "tombstones"
* use mediatype instead of mimetype throughout
* make the case of field names more consistent
Acknowledgments
TODO acknowledge.
Author's Address
Rohan Mahy
Rohan Mahy Consulting Services
Email: rohan.ietf@gmail.com
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