Media Over QUIC C. Jennings Internet-Draft S. Nandakumar Intended status: Standards Track Cisco Expires: 7 January 2027 6 July 2026 MOCHA Reactions: Real-Time Reactions over MoQ Transport draft-jennings-moq-mocha-reactions-00 Abstract This document specifies reactions for MOCHA (MoQ Open Communication & Hosting Architecture). It supports message-targeted reactions (emoji on a specific chat message) and standalone reactions (engagement signals such as applause or raised hands). About This Document This note is to be removed before publishing as an RFC. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-jennings-moq-mocha-reactions/. Discussion of this document takes place on the Media Over QUIC Working Group mailing list (mailto:moq@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/moq/. Subscribe at https://www.ietf.org/mailman/listinfo/moq/. 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 working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents 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 "work in progress." This Internet-Draft will expire on 7 January 2027. Jennings & Nandakumar Expires 7 January 2027 [Page 1] Internet-Draft mocha-reactions July 2026 Copyright Notice Copyright (c) 2026 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 described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3 3. Reaction Track Naming . . . . . . . . . . . . . . . . . . . . 3 3.1. Reactions Namespace . . . . . . . . . . . . . . . . . . . 3 3.2. Track Names . . . . . . . . . . . . . . . . . . . . . . . 3 3.3. Object Semantics . . . . . . . . . . . . . . . . . . . . 3 4. Reaction Format . . . . . . . . . . . . . . . . . . . . . . . 3 4.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 3 4.2. Reaction Structure . . . . . . . . . . . . . . . . . . . 3 4.3. Fields . . . . . . . . . . . . . . . . . . . . . . . . . 4 4.4. Reaction Types . . . . . . . . . . . . . . . . . . . . . 4 4.5. Reaction Value Encoding . . . . . . . . . . . . . . . . . 5 4.6. Reaction Removal . . . . . . . . . . . . . . . . . . . . 6 5. Sending Reactions . . . . . . . . . . . . . . . . . . . . . . 6 5.1. Rate Limiting . . . . . . . . . . . . . . . . . . . . . . 6 6. Receiving Reactions . . . . . . . . . . . . . . . . . . . . . 6 6.1. Processing Message-Targeted Reactions . . . . . . . . . . 6 6.2. Processing Standalone Reactions . . . . . . . . . . . . . 7 7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 9. Normative References . . . . . . . . . . . . . . . . . . . . 7 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction This document specifies how MOCHA enables real-time reaction exchange using MOQT's publish/subscribe model. Two modes are supported: Message-Targeted Reactions: Emoji responses referencing a specific chat message MsgID. Jennings & Nandakumar Expires 7 January 2027 [Page 2] Internet-Draft mocha-reactions July 2026 Standalone Reactions: Standalone engagement signals (applause, raised hands) directed at the channel as a whole. Both modes use the same track structure. 2. Conventions and Definitions See BCP 14 [RFC2119] [RFC8174]. This document uses terminology defined in [MOCHA-ARCH] and MOQT primitives defined in [MoQTransport]. Message identifiers (MsgID) are defined in [MOCHA-CHAT]. 3. Reaction Track Naming 3.1. Reactions Namespace ("mocha_v1", , , "reactions", , , ) HClientID and HDevID are derived per [MOCHA-IDENTITY], Section "Identifier Derivation". 3.2. Track Names Each device publishes reactions on its own track: react_v1_ 3.3. Object Semantics Within each group, reactions are assigned sequentially increasing Object IDs starting at 0. Each reaction occupies one MOQT object. 4. Reaction Format 4.1. Encoding Reactions are encoded as JSON [JSON] and compressed per the MOCHA_COMPRESSION track property defined in [MOCHA-CHAT]. 4.2. Reaction Structure Jennings & Nandakumar Expires 7 January 2027 [Page 3] Internet-Draft mocha-reactions July 2026 { "type": 1, "value": "thumbs-up", "ts": 1715788800000, "sender": { "userId": "", "devId": "" }, "target": { "msgId": "a1b2c3...f0a1b2" }, "ext": {} } 4.3. Fields type (REQUIRED): Integer reaction type. See Section 4.4. value (REQUIRED): String identifying the specific reaction (e.g., "thumbs-up", "fire", "raise"). ts (REQUIRED): Creation time in milliseconds since Unix epoch. sender (REQUIRED): Object with userId and devId fields. target (OPTIONAL): Object with msgId field (hex-encoded MsgID per [MOCHA-CHAT]). Present for message-targeted reactions; absent for standalone reactions. {#target-field} ext (OPTIONAL): Extension fields. Implementations MUST ignore unknown keys. 4.4. Reaction Types +=======+==========+=========================================+ | Value | Name | Description | +=======+==========+=========================================+ | 1 | emoji | Emoji reaction (heart, fire, thumbs-up) | +-------+----------+-----------------------------------------+ | 2 | vote | Poll or vote response | +-------+----------+-----------------------------------------+ | 3 | raise | Raise/lower hand | +-------+----------+-----------------------------------------+ | 4 | applause | Applause or cheer | +-------+----------+-----------------------------------------+ | 5 | custom | Application-defined reaction | +-------+----------+-----------------------------------------+ Jennings & Nandakumar Expires 7 January 2027 [Page 4] Internet-Draft mocha-reactions July 2026 Table 1 Extensible via IANA registry. 4.5. Reaction Value Encoding Each reaction type defines integer encodings for its values: Emoji (type 1): +=========+=============+ | Integer | Value | +=========+=============+ | 1 | thumbs-up | +---------+-------------+ | 2 | thumbs-down | +---------+-------------+ | 3 | heart | +---------+-------------+ | 4 | fire | +---------+-------------+ | 5 | laugh | +---------+-------------+ | 6 | sad | +---------+-------------+ | 7 | wow | +---------+-------------+ | 8 | clap | +---------+-------------+ | 9 | thinking | +---------+-------------+ | 10 | eyes | +---------+-------------+ Table 2 TODO: The range of emoji values to be supported is not clear at this point and further discussion is needed. Values 11-127 are reserved for future standard emoji. Values 128+ are available for application-defined emoji. Raise (type 3): Jennings & Nandakumar Expires 7 January 2027 [Page 5] Internet-Draft mocha-reactions July 2026 +=========+=======+ | Integer | Value | +=========+=======+ | 1 | raise | +---------+-------+ | 2 | lower | +---------+-------+ Table 3 Vote (type 2) and Applause (type 4) value encodings are application- defined. 4.6. Reaction Removal To retract a reaction, a device publishes an object with the same type, value, and target, plus "remove": true. The receiver removes the matching reaction from display. 5. Sending Reactions To send a reaction, a device publishes a MOQT object to its track within the reactions namespace. 5.1. Rate Limiting * Message-targeted: At most 1 reaction of a given type per message per device (newer replaces older). * Standalone: At most 1 reaction per second per device. Relays MAY enforce rate limits and drop excess objects. 6. Receiving Reactions A participant discovers reaction tracks via SUBSCRIBE_NAMESPACE on the reactions namespace prefix, then subscribes to the announced tracks. 6.1. Processing Message-Targeted Reactions 1. Look up the referenced MsgID in the local message store. 2. Display the reaction on that message. 3. Same sender + same type + same target: newer replaces older. 4. If remove=true, remove the matching reaction. Jennings & Nandakumar Expires 7 January 2027 [Page 6] Internet-Draft mocha-reactions July 2026 6.2. Processing Standalone Reactions 1. Display as a transient signal (e.g., floating emoji, applause indicator). 2. For raise-hand: maintain a queue until "lower" is received. 7. Security Considerations TODO 8. IANA Considerations TODO 9. Normative References [JSON] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, DOI 10.17487/RFC8259, December 2017, . [MOCHA] "*** BROKEN REFERENCE ***". [MOCHA-ARCH] "*** BROKEN REFERENCE ***". [MOCHA-CHAT] "*** BROKEN REFERENCE ***". [MOCHA-IDENTITY] "*** BROKEN REFERENCE ***". [MoQTransport] Nandakumar, S., Vasiliev, V., Swett, I., and A. Frindell, "Media over QUIC Transport", Work in Progress, Internet- Draft, draft-ietf-moq-transport-18, 12 May 2026, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . Jennings & Nandakumar Expires 7 January 2027 [Page 7] Internet-Draft mocha-reactions July 2026 Acknowledgments TODO Authors' Addresses Cullen Jennings Cisco Email: fluffy@iii.ca Suhas Nandakumar Cisco Email: snandaku@cisco.com Jennings & Nandakumar Expires 7 January 2027 [Page 8]