Media Over QUIC L. Pardue Internet-Draft Cloudflare Intended status: Informational M. Engelbart Expires: 11 July 2026 Technical University of Munich A. Sharma Meta 7 January 2026 MoQ qlog event definitions draft-pardue-moq-qlog-moq-events-04 Abstract This document defines a qlog event schema containing concrete events for MoQ. 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://LPardue.github.io/draft-pardue-moq-qlog-moq-events/draft- pardue-moq-qlog-moq-events.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft- pardue-moq-qlog-moq-events/. Discussion of this document takes place on the Media Over QUIC 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/. Source for this draft and an issue tracker can be found at https://github.com/LPardue/draft-pardue-moq-qlog-moq-events. 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/. Pardue, et al. Expires 11 July 2026 [Page 1] Internet-Draft MoQ qlog event definitions January 2026 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 11 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 . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Usage with QUIC . . . . . . . . . . . . . . . . . . . . . 5 2. Conventions and Definitions . . . . . . . . . . . . . . . . . 5 3. Event Schema Definition . . . . . . . . . . . . . . . . . . . 5 3.1. Draft Event Schema Identification . . . . . . . . . . . . 5 4. MOQT Events . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1. control_message_created . . . . . . . . . . . . . . . . . 7 4.2. control_message_parsed . . . . . . . . . . . . . . . . . 7 4.3. stream_type_set . . . . . . . . . . . . . . . . . . . . . 8 4.4. object_datagram_created . . . . . . . . . . . . . . . . . 8 4.5. object_datagram_parsed . . . . . . . . . . . . . . . . . 8 4.6. subgroup_header_created . . . . . . . . . . . . . . . . . 9 4.7. subgroup_header_parsed . . . . . . . . . . . . . . . . . 9 4.8. subgroup_object_created . . . . . . . . . . . . . . . . . 10 4.9. subgroup_object_parsed . . . . . . . . . . . . . . . . . 10 4.10. fetch_header_created . . . . . . . . . . . . . . . . . . 11 4.11. fetch_header_parsed . . . . . . . . . . . . . . . . . . . 11 4.12. fetch_object_created . . . . . . . . . . . . . . . . . . 11 4.13. fetch_object_parsed . . . . . . . . . . . . . . . . . . . 12 5. MOQT Data Type Definitions . . . . . . . . . . . . . . . . . 12 5.1. Owner . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.2. MOQTSetupParameter . . . . . . . . . . . . . . . . . . . 13 5.2.1. MOQTAuthoritySetupParameter . . . . . . . . . . . . . 13 5.2.2. MOQTAuthorizationTokenSetupParameter . . . . . . . . 13 5.2.3. MOQTPathSetupParameter . . . . . . . . . . . . . . . 14 Pardue, et al. Expires 11 July 2026 [Page 2] Internet-Draft MoQ qlog event definitions January 2026 5.2.4. MOQTMaxRequestIdSetupParameter . . . . . . . . . . . 14 5.2.5. MOQTMaxAuthTokenCacheSizeSetupParameter . . . . . . . 14 5.2.6. MOQTImplementationSetupParameter . . . . . . . . . . 14 5.2.7. MOQTUnknownSetupParameter . . . . . . . . . . . . . . 15 5.3. MOQTParameter . . . . . . . . . . . . . . . . . . . . . . 15 5.3.1. MOQTAuthorizationTokenParameter . . . . . . . . . . . 15 5.3.2. MOQTDeliveryTimeoutParameter . . . . . . . . . . . . 16 5.3.3. MOQTMaxCacheDurationParameter . . . . . . . . . . . . 16 5.3.4. MOQTUnknownParameter . . . . . . . . . . . . . . . . 16 5.4. MOQTByteString . . . . . . . . . . . . . . . . . . . . . 16 5.5. MOQTLocation . . . . . . . . . . . . . . . . . . . . . . 17 5.6. MOQTControlMessage . . . . . . . . . . . . . . . . . . . 17 5.6.1. MOQTClientSetupMessage . . . . . . . . . . . . . . . 18 5.6.2. MOQTServerSetupMessage . . . . . . . . . . . . . . . 19 5.6.3. MOQTGoaway . . . . . . . . . . . . . . . . . . . . . 19 5.6.4. MOQTMaxRequestId . . . . . . . . . . . . . . . . . . 19 5.6.5. MOQTRequestsBlocked . . . . . . . . . . . . . . . . . 19 5.6.6. MOQTSubscribe . . . . . . . . . . . . . . . . . . . . 19 5.6.7. MOQTSubscribeOk . . . . . . . . . . . . . . . . . . . 20 5.6.8. MOQTSubscribeError . . . . . . . . . . . . . . . . . 20 5.6.9. MOQTSubscribeUpdate . . . . . . . . . . . . . . . . . 20 5.6.10. MOQTUnsubscribe . . . . . . . . . . . . . . . . . . . 21 5.6.11. MOQTPublishDone . . . . . . . . . . . . . . . . . . . 21 5.6.12. MOQTPublish . . . . . . . . . . . . . . . . . . . . . 21 5.6.13. MOQTPublishOk . . . . . . . . . . . . . . . . . . . . 22 5.6.14. MOQTPublishError . . . . . . . . . . . . . . . . . . 22 5.6.15. MOQTFetch . . . . . . . . . . . . . . . . . . . . . . 22 5.6.16. MOQTFetchOk . . . . . . . . . . . . . . . . . . . . . 23 5.6.17. MOQTFetchError . . . . . . . . . . . . . . . . . . . 23 5.6.18. MOQTFetchCancel . . . . . . . . . . . . . . . . . . . 24 5.6.19. MOQTTrackStatus . . . . . . . . . . . . . . . . . . . 24 5.6.20. MOQTTrackStatusOk . . . . . . . . . . . . . . . . . . 24 5.6.21. MOQTTrackStatusError . . . . . . . . . . . . . . . . 25 5.6.22. MOQTPublishNamespace . . . . . . . . . . . . . . . . 25 5.6.23. MOQTPublishNamespaceOk . . . . . . . . . . . . . . . 25 5.6.24. MOQTPublishNamespaceError . . . . . . . . . . . . . . 26 5.6.25. MOQTPublishNamespaceDone . . . . . . . . . . . . . . 26 5.6.26. MOQTPublishNamespaceCancel . . . . . . . . . . . . . 26 5.6.27. MOQTSubscribeNamespace . . . . . . . . . . . . . . . 26 5.6.28. MOQTSubscribeNamespaceOk . . . . . . . . . . . . . . 26 5.6.29. MOQTSubscribeNamespaceError . . . . . . . . . . . . . 27 5.6.30. MOQTUnsubscribeNamespace . . . . . . . . . . . . . . 27 5.7. MOQTExtensionHeader . . . . . . . . . . . . . . . . . . . 27 6. Security Considerations . . . . . . . . . . . . . . . . . . . 27 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 27 8. Normative References . . . . . . . . . . . . . . . . . . . . 28 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 29 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 Pardue, et al. Expires 11 July 2026 [Page 3] Internet-Draft MoQ qlog event definitions January 2026 1. Introduction This document defines a qlog event schema (Section 8 of [QLOG-MAIN]) containing concrete events for Media over QUIC Transport [MOQT]. The event namespace with identifier moqt is defined; see Section 3. In this namespace multiple events derive from the qlog abstract Event class (Section 7 of [QLOG-MAIN]), each extending the "data" field and defining their "name" field values and semantics. Table 1 summarizes the name value of each event type that is defined in this specification. Some event data fields use complex data types. These are represented as enums or re-usable definitions, which are grouped together on the bottom of this document for clarity. +==============================+============+==============+ | Name value | Importance | Definition | +==============================+============+==============+ | moqt:control_message_created | Core | Section 4.1 | +------------------------------+------------+--------------+ | moqt:control_message_parsed | Core | Section 4.2 | +------------------------------+------------+--------------+ | moqt:stream_type_set | Core | Section 4.3 | +------------------------------+------------+--------------+ | moqt:object_datagram_created | Core | Section 4.4 | +------------------------------+------------+--------------+ | moqt:object_datagram_parsed | Core | Section 4.5 | +------------------------------+------------+--------------+ | moqt:subgroup_header_created | Core | Section 4.6 | +------------------------------+------------+--------------+ | moqt:subgroup_header_parsed | Core | Section 4.7 | +------------------------------+------------+--------------+ | moqt:subgroup_object_created | Core | Section 4.8 | +------------------------------+------------+--------------+ | moqt:subgroup_object_parsed | Core | Section 4.9 | +------------------------------+------------+--------------+ | moqt:fetch_header_created | Core | Section 4.10 | +------------------------------+------------+--------------+ | moqt:fetch_header_parsed | Core | Section 4.11 | +------------------------------+------------+--------------+ | moqt:fetch_object_created | Core | Section 4.12 | +------------------------------+------------+--------------+ | moqt:fetch_object_parsed | Core | Section 4.13 | +------------------------------+------------+--------------+ Table 1: MOQT Events Pardue, et al. Expires 11 July 2026 [Page 4] Internet-Draft MoQ qlog event definitions January 2026 1.1. Usage with QUIC The events described in this document can be used with or without logging the related QUIC events defined in [QLOG-QUIC]. If used with QUIC events, the QUIC document takes precedence in terms of recommended filenames and trace separation setups. If used without QUIC events, it is recommended that the implementation assign a globally unique identifier to each MOQT session. This ID can then be used as the value of the qlog "group_id" field, as well as the qlog filename or file identifier, potentially suffixed by the vantagepoint type (For example, abcd1234_server.qlog would contain the server-side trace of the connection with GUID abcd1234). 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 event and data structure definitions in ths document are expressed in the Concise Data Definition Language [CDDL] and its extensions described in [QLOG-MAIN]. The following fields from [QLOG-MAIN] are imported and used: name, namespace, type, data, group_id, RawInfo, and time-related fields. Events are defined with an importance level as described in Section 8.3 of [QLOG-MAIN]. As is the case for [QLOG-MAIN], the qlog schema definitions in this document are intentionally agnostic to serialization formats. The choice of format is an implementation decision. 3. Event Schema Definition This document describes how the MOQT protocol is expressed in qlog with an event schema. Per the requirements in Section 8 of [QLOG-MAIN], this document registers the moqt namespace. The event schema URI is urn:ietf:params:qlog:events:moqt. 3.1. Draft Event Schema Identification This section is to be removed before publishing as an RFC. Pardue, et al. Expires 11 July 2026 [Page 5] Internet-Draft MoQ qlog event definitions January 2026 Only implementations of the final, published RFC can use the events belonging to the event schema with the URI urn:ietf:params:qlog:events:moqt. Until such an RFC exists, implementations MUST NOT identify themselves using this URI. Implementations of draft versions of the event schema MUST append the string "-" and the corresponding draft number to the URI. For example, draft 99 of this document is identified using the URI urn:ietf:params:qlog:events:moqt-99. The namespace identifier itself is not affected by this requirement. 4. MOQT Events MOQT events extend the $ProtocolEventData extension point defined in [QLOG-MAIN]. Additionally, they allow for direct extensibility by their use of per-event extension points via the $$ CDDL "group socket" syntax, as also described in [QLOG-MAIN]. MOQTEventData = MOQTControlMessageCreated / MOQTControlMessageParsed / MOQTStreamTypeSet / MOQTObjectDatagramCreated / MOQTObjectDatagramParsed / MOQTSubgroupHeaderCreated / MOQTSubgroupHeaderParsed / MOQTSubgroupObjectCreated / MOQTSubgroupObjectParsed / MOQTFetchHeaderCreated / MOQTFetchHeaderParsed / MOQTFetchObjectCreated / MOQTFetchObjectParsed $ProtocolEventData /= MOQTEventData Figure 1: MOQTEventData definition and ProtocolEventData extension MOQT events are logged when a certain condition happens at the application layer, and there isn't always a one to one mapping between HTTP and QUIC events. The exchange of data between the HTTP and QUIC layer is logged via the "stream_data_moved" and "datagram_data_moved" events in [QLOG-QUIC]. The concrete MOQT event types are further defined below, their type identifier is the heading name. Pardue, et al. Expires 11 July 2026 [Page 6] Internet-Draft MoQ qlog event definitions January 2026 Some MOQT messages include a reason phrase that can provide additional information in the format of a byte sequences. However, these sequences are not guaranteed to be presentable as UTF-8. In order to accomodate various encodings, where the wire image of a message includes a reason phrase, the MOQT qlog event type, includes two option fields: reason (for UTF-8) and reason_bytes (a hex-encoded string representing raw bytes). Implementations SHOULD log at least one format, but MAY log both or none. 4.1. control_message_created The control_message_created event is emitted when a control message is created. It has Core importance level. The definition of control message content is in Section 5.6. MOQTControlMessageCreated = { stream_id: uint64 ? length: uint64 message: $MOQTControlMessage ? raw: RawInfo * $$moqt-controlmessagecreated-extension } Figure 2: MOQTControlMessageCreated definition 4.2. control_message_parsed The control_message_parsed event is emitted when a control message is parsed. It has Core importance level. The definition of control message content is in Section 5.6. MOQTControlMessageParsed = { stream_id: uint64 ? length: uint64 message: $MOQTControlMessage ? raw: RawInfo * $$moqt-controlmessageparsed-extension } Figure 3: MOQTControlMessageParsed definition Pardue, et al. Expires 11 July 2026 [Page 7] Internet-Draft MoQ qlog event definitions January 2026 4.3. stream_type_set The stream_type_set event conveys when a MOQT stream type becomes known. It has Base importance level. MOQTStreamTypeSet = { ? owner: Owner stream_id: uint64 stream_type: $MOQTStreamType * $$moqt-streamtypeset-extension } $MOQTStreamType /= "control" / "subgroup_header" / "fetch_header" Figure 4: MOQTStreamTypeSet definition 4.4. object_datagram_created The object_datagram_created event is emitted when the OBJECT_DATAGRAM message is created. It has Core importance level. MOQTObjectDatagramCreated = { track_alias: uint64 group_id: uint64 ? object_id: uint64 publisher_priority: uint8 ? extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] ? object_status: uint64 ? object_payload: RawInfo end_of_group: bool * $$moqt-objectdatagramcreated-extension } Figure 5: MOQTObjectDatagramCreated definition 4.5. object_datagram_parsed The object_datagram_parsed event is emitted when the OBJECT_DATAGRAM message is parsed. It has Core importance level. Pardue, et al. Expires 11 July 2026 [Page 8] Internet-Draft MoQ qlog event definitions January 2026 MOQTObjectDatagramParsed = { track_alias: uint64 group_id: uint64 ? object_id: uint64 publisher_priority: uint8 ? extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] ? object_status: uint64 ? object_payload: RawInfo end_of_group: bool * $$moqt-objectdatagramparsed-extension } Figure 6: MOQTObjectDatagramParsed definition 4.6. subgroup_header_created The subgroup_header_created event is emitted when a stream begins and a SUBGROUP_HEADER is created. It has Core importance level; see Section 9.2 of [QLOG-MAIN]. The SUBGROUP_HEADER object in MoQT uses 12 type values to encode various properties. The subgroup_header_created event conveys these as explicit fields, such as contains_end_of_group. If the subgroup_id is the object_id of the first object, the subgroup_id is omitted. Otherwise, it is included with the relevant value. MOQTSubgroupHeaderCreated = { stream_id: uint64 track_alias: uint64 group_id: uint64 ? subgroup_id: uint64 publisher_priority: uint8 contains_end_of_group: bool extensions_present: bool * $$moqt-subgroupheadercreated-extension } Figure 7: MOQTSubgroupHeaderCreated definition 4.7. subgroup_header_parsed The subgroup_header_parsed event is emitted when the SUBGROUP_HEADER is parsed. It has Core importance level. Pardue, et al. Expires 11 July 2026 [Page 9] Internet-Draft MoQ qlog event definitions January 2026 The SUBGROUP_HEADER object in MoQT uses 12 type values to encode various properties. The event conveys these as explicit fields, such as contains_end_of_group. If the subgroup_id is the object_id of the first object, the subgroup_id is omitted. Otherwise, it is included with the relevant value. MOQTSubgroupHeaderParsed = { stream_id: uint64 track_alias: uint64 group_id: uint64 ? subgroup_id: uint64 publisher_priority: uint8 contains_end_of_group: bool extensions_present: bool * $$moqt-subgroupheaderparsed-extension } Figure 8: MOQTSubgroupHeaderParsed definition 4.8. subgroup_object_created The subgroup_object_created event is emitted when a subgroup object is created. It has Core importance level. MOQTSubgroupObjectCreated = { stream_id: uint64 ? group_id: uint64 ? subgroup_id: uint64 object_id: uint64 extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-subgroupobjectcreated-extension } Figure 9: MOQTSubgroupObjectCreated definition 4.9. subgroup_object_parsed The subgroup_object_parsed event is emitted when a subgroup object is parsed. It has Core importance level. Pardue, et al. Expires 11 July 2026 [Page 10] Internet-Draft MoQ qlog event definitions January 2026 MOQTSubgroupObjectParsed = { stream_id: uint64 ? group_id: uint64 ? subgroup_id: uint64 object_id: uint64 extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-subgroupobjectparsed-extension } Figure 10: MOQTSubgroupObjectParsed definition 4.10. fetch_header_created The fetch_header_created event is emitted when a stream begins and a FETCH_HEADER is created. It has Core importance level. MOQTFetchHeaderCreated = { stream_id: uint64 request_id: uint64 * $$moqt-fetchheadercreated-extension } Figure 11: MOQTFetchHeaderCreated definition 4.11. fetch_header_parsed The fetch_header_parsed event is emitted when the SUBGROUP_HEADER is parsed. It has Core importance level. MOQTFetchHeaderParsed = { stream_id: uint64 request_id: uint64 * $$moqt-fetchheaderparsed-extension } Figure 12: MOQTFetchHeaderParsed definition 4.12. fetch_object_created The fetch_object_created event is emitted when a fetch object is created. It has Core importance level. Pardue, et al. Expires 11 July 2026 [Page 11] Internet-Draft MoQ qlog event definitions January 2026 MOQTFetchObjectCreated = { stream_id: uint64 group_id: uint64 subgroup_id: uint64 object_id: uint64 publisher_priority: uint8 extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-fetchobjectcreated-extension } Figure 13: MOQTFetchObjectCreated definition 4.13. fetch_object_parsed The fetch_object_parsed event is emitted when a fetch object is parsed. It has Core importance level. MOQTFetchObjectParsed = { stream_id: uint64 group_id: uint64 subgroup_id: uint64 object_id: uint64 publisher_priority: uint8 extension_headers_length: uint64 ? extension_headers: [* MOQTExtensionHeader] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-fetchobjectparsed-extension } Figure 14: MOQTFetchObjectParsed definition 5. MOQT Data Type Definitions The following data type definitions can be used in MOQT events. 5.1. Owner Owner = "local" / "remote" Pardue, et al. Expires 11 July 2026 [Page 12] Internet-Draft MoQ qlog event definitions January 2026 Figure 15: Owner definition 5.2. MOQTSetupParameter The generic $MOQTSetupParameter is defined here as a CDDL "type socket" extension point. It can be extended to support additional MOQT Setup Parameters. ; The MOQTSetupParameter is any key-value map (e.g., JSON object) $MOQTSetupParameter /= { * text => any } Figure 16: MOQTSetupParameter type socket definition MOQTBaseSetupParameters /= MOQTAuthoritySetupParameter / MOQTAuthorizationTokenSetupParameter / MOQTPathSetupParameter / MOQTMaxRequestIdSetupParameter / MOQTMaxAuthTokenCacheSizeSetupParameter / MOQTImplementationSetupParameter / MOQTUnknownSetupParameter $MOQTSetupParameter /= MOQTBaseSetupParameters Figure 17: MOQTBaseSetupParameters definition 5.2.1. MOQTAuthoritySetupParameter MOQTAuthoritySetupParameter = { name: "authority" value: text } Figure 18: MOQTAuthoritySetupParameter definition 5.2.2. MOQTAuthorizationTokenSetupParameter Pardue, et al. Expires 11 July 2026 [Page 13] Internet-Draft MoQ qlog event definitions January 2026 MOQTAuthorizationTokenSetupParameter = { name: "authorization_token" alias_type: $MOQTAliasType ? token_alias: uint64 ? token_type: uint64 ? token_value: RawInfo } $MOQTAliasType /= "delete" / "register" / "use_alias" / "use_value" Figure 19: MOQTAuthorizationTokenSetupParameter definition 5.2.3. MOQTPathSetupParameter MOQTPathSetupParameter = { name: "path" value: text } Figure 20: MOQTPathSetupParameter definition 5.2.4. MOQTMaxRequestIdSetupParameter MOQTMaxRequestIdSetupParameter = { name: "max_request_id" value: uint64 } Figure 21: MOQTMaxRequestIdSetupParameter definition 5.2.5. MOQTMaxAuthTokenCacheSizeSetupParameter MOQTMaxAuthTokenCacheSizeSetupParameter = { name: "max_auth_token_cache_size" value: uint64 } Figure 22: MOQTMaxAuthTokenCacheSizeSetupParameter definition 5.2.6. MOQTImplementationSetupParameter MOQTImplementationSetupParameter = { name: "implementation" value: text } Pardue, et al. Expires 11 July 2026 [Page 14] Internet-Draft MoQ qlog event definitions January 2026 Figure 23: MOQTImplementationSetupParameter definition 5.2.7. MOQTUnknownSetupParameter MOQTUnknownSetupParameter = { name:"unknown" name_bytes: uint64 ? length: uint64 ? value: uint64 ? value_bytes: RawInfo } Figure 24: MOQTUnknownSetupParameter definition 5.3. MOQTParameter The generic $MOQTParameter is defined here as a CDDL "type socket" extension point. It can be extended to support additional MOQT Parameters. ; The MOQTParameter is any key-value map (e.g., JSON object) $MOQTParameter /= { * text => any } Figure 25: MOQTParameter type socket definition MOQTBaseParameters /= MOQTAuthorizationTokenParameter / MOQTDeliveryTimeoutParameter / MOQTMaxCacheDurationParameter / MOQTUnknownParameter $MOQTParameter /= MOQTBaseParameters Figure 26: MOQTBaseParameters definition 5.3.1. MOQTAuthorizationTokenParameter MOQTAuthorizationTokenParameter = { name: "authorization_token" alias_type: uint64 ? token_alias: uint64 ? token_type: uint64 ? token_value: RawInfo } Figure 27: MOQTAuthorizationTokenParameter definition Pardue, et al. Expires 11 July 2026 [Page 15] Internet-Draft MoQ qlog event definitions January 2026 5.3.2. MOQTDeliveryTimeoutParameter MOQTDeliveryTimeoutParameter = { name: "delivery_timeout" value: uint64 } Figure 28: MOQTDeliveryTimeoutParameter definition 5.3.3. MOQTMaxCacheDurationParameter MOQTMaxCacheDurationParameter = { name: "max_cache_duration" value: uint64 } Figure 29: MOQTMaxCacheDurationParameter definition 5.3.4. MOQTUnknownParameter MOQTUnknownParameter = { name:"unknown" name_bytes: uint64 ? length: uint64 ? value: uint64 ? value_bytes: RawInfo } Figure 30: MOQTUnknownParameter definition 5.4. MOQTByteString The MOQTByteString type allows representing MOQT bytestrings, such as the value of a Track or Track Namespace tuple field, using two different encodings. The value field can be used for bytestrings that can be encoded in UTF-8. The value_bytes field can be used for bytestrings of any type by using the hexstring encoding. Implementations SHOULD populate one of either the value or value_bytes field. Populating both fields is redundant. MOQTByteString = { ? value: text ? value_bytes: hexstring } Figure 31: MOQTByteString definition Pardue, et al. Expires 11 July 2026 [Page 16] Internet-Draft MoQ qlog event definitions January 2026 5.5. MOQTLocation A Location, as defined in Section 1.3.1 of [MOQT] MOQTLocation = { group: uint64 object: uint64 } Figure 32 5.6. MOQTControlMessage The generic $MOQTControlMessage is defined here as a CDDL "type socket" extension point. It can be extended to support additional MOQT control message types. ; The MOQTControlMessage is any key-value map (e.g., JSON object) $MOQTControlMessage /= { * text => any } Figure 33: MOQTControlMessage type socket definition The MOQT control message types defined in this document are as follows: Pardue, et al. Expires 11 July 2026 [Page 17] Internet-Draft MoQ qlog event definitions January 2026 MOQTBaseControlMessages = MOQTClientSetupMessage / MOQTServerSetupMessage / MOQTGoaway / MOQTMaxRequestId / MOQTRequestsBlocked / MOQTSubscribe / MOQTSubscribeOk / MOQTSubscribeError / MOQTSubscribeUpdate / MOQTUnsubscribe / MOQTPublishDone / MOQTPublish / MOQTPublishOk / MOQTPublishError / MOQTFetch / MOQTFetchOk / MOQTFetchError / MOQTFetchCancel / MOQTTrackStatus / MOQTTrackStatusOk / MOQTTrackStatusError / MOQTPublishNamespace / MOQTPublishNamespaceOk / MOQTPublishNamespaceError / MOQTPublishNamespaceDone / MOQTPublishNamespaceCancel / MOQTSubscribeNamespace / MOQTSubscribeNamespaceOk / MOQTSubscribeNamespaceError / MOQTUnsubscribeNamespace $MOQTControlMessage /= MOQTBaseControlMessages Figure 34: MOQTBaseControlMessages definition 5.6.1. MOQTClientSetupMessage MOQTClientSetupMessage = { type: "client_setup" number_of_supported_versions: uint64 supported_versions: [* uint64] number_of_parameters: uint64 ? setup_parameters: [* $MOQTSetupParameter] } Figure 35: MOQTClientSetupMessage definition Pardue, et al. Expires 11 July 2026 [Page 18] Internet-Draft MoQ qlog event definitions January 2026 5.6.2. MOQTServerSetupMessage MOQTServerSetupMessage = { type: "server_setup" selected_version: uint64 number_of_parameters: uint64 ? setup_parameters: [* $MOQTSetupParameter] } Figure 36: MOQTServerSetupMessage definition 5.6.3. MOQTGoaway MOQTGoaway = { type: "goaway" ? length: uint64 new_session_uri: RawInfo } Figure 37: MOQTGoaway definition 5.6.4. MOQTMaxRequestId MOQTMaxRequestId = { type: "max_request_id" request_id: uint64 } Figure 38: MOQTMaxRequestId definition 5.6.5. MOQTRequestsBlocked MOQTRequestsBlocked = { type: "requests_blocked" maximum_request_id: uint64 } Figure 39: MOQTRequestsBlocked definition 5.6.6. MOQTSubscribe Pardue, et al. Expires 11 July 2026 [Page 19] Internet-Draft MoQ qlog event definitions January 2026 MOQTSubscribe = { type: "subscribe" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString subscriber_priority: uint8 group_order: uint8 forward: uint8 filter_type: uint64 ? start_location: MOQTLocation ? end_group: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 40: MOQTSubscribe definition 5.6.7. MOQTSubscribeOk MOQTSubscribeOk = { type: "subscribe_ok" request_id: uint64 track_alias: uint64 expires: uint64 group_order: uint8 content_exists: uint8 ? largest_location: MOQTLocation number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 41: MOQTSubscribeOk definition 5.6.8. MOQTSubscribeError MOQTSubscribeError = { type: "subscribe_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 42: MOQTSubscribeError definition 5.6.9. MOQTSubscribeUpdate Pardue, et al. Expires 11 July 2026 [Page 20] Internet-Draft MoQ qlog event definitions January 2026 MOQTSubscribeUpdate = { type: "subscribe_update" request_id: uint64 subscription_request_id: uint64 start_location: MOQTLocation end_group: uint64 subscriber_priority: uint8 forward: uint8 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 43: MOQTSubscribeUpdate definition 5.6.10. MOQTUnsubscribe MOQTUnsubscribe = { type: "unsubscribe" request_id: uint64 } Figure 44: MOQTUnsubscribe definition 5.6.11. MOQTPublishDone MOQTPublishDone = { type: "publish_done" request_id: uint64 status_code: uint64 stream_count: uint64 ? reason: text ? reason_bytes: hexstring } Figure 45: MOQTPublishDone definition 5.6.12. MOQTPublish Pardue, et al. Expires 11 July 2026 [Page 21] Internet-Draft MoQ qlog event definitions January 2026 MOQTPublish = { type: "publish" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString track_alias: uint64 group_order: uint8 content_exists: uint8 ? largest: MOQTLocation forward: uint8 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 46: MOQTPublish definition 5.6.13. MOQTPublishOk MOQTPublishOk = { type: "publish_ok" request_id: uint64 forward: uint8 subscriber_priority: uint8 group_order: uint8 filter_type: uint64 ? start: MOQTLocation ? end_group: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 47: MOQTPublishOk definition 5.6.14. MOQTPublishError MOQTPublishError = { type: "publish_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 48: MOQTPublishError definition 5.6.15. MOQTFetch Pardue, et al. Expires 11 July 2026 [Page 22] Internet-Draft MoQ qlog event definitions January 2026 MOQTFetch = { type: "fetch" request_id: uint64 subscriber_priority: uint8 group_order: uint8 fetch_type: $MOQTFetchType ? standalone_fetch: $MOQTStandaloneFetch ? joining_fetch: $MOQTJoiningFetch ? parameters: [* $MOQTParameter] } $MOQTStandaloneFetch = { track_namespace: [ *MOQTByteString] track_name: MOQTByteString start_location: MOQTLocation end_location: MOQTLocation } $MOQTJoiningFetch = { joining_request_id: uint64 joining_start: uint64 } $MOQTFetchType /= "standalone" / "absolute_joining" / "relative_joining" Figure 49: MOQTFetch definition 5.6.16. MOQTFetchOk MOQTFetchOk = { type: "fetch_ok" request_id: uint64 group_order: uint8 end_of_track: uint8 end_location: MOQTLocation number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 50: MOQTFetchOk definition 5.6.17. MOQTFetchError Pardue, et al. Expires 11 July 2026 [Page 23] Internet-Draft MoQ qlog event definitions January 2026 MOQTFetchError = { type: "fetch_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 51: MOQTFetchError definition 5.6.18. MOQTFetchCancel MOQTFetchCancel = { type: "fetch_cancel" request_id: uint64 } Figure 52: MOQTFetchCancel definition 5.6.19. MOQTTrackStatus MOQTTrackStatus = { type: "track_status" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString subscriber_priority: uint8 group_order: uint8 forward: uint8 filter_type: uint64 ? start_location: MOQTLocation ? end_group: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 53: MOQTTrackStatus definition 5.6.20. MOQTTrackStatusOk Pardue, et al. Expires 11 July 2026 [Page 24] Internet-Draft MoQ qlog event definitions January 2026 MOQTTrackStatusOk = { type: "track_status_ok" request_id: uint64 track_alias: uint64 expires: uint64 group_order: uint8 content_exists: uint8 ? largest_location: MOQTLocation number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 54: MOQTTrackStatusOk definition 5.6.21. MOQTTrackStatusError MOQTTrackStatusError = { type: "track_status_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 55: MOQTTrackStatusError definition 5.6.22. MOQTPublishNamespace MOQTPublishNamespace = { type: "publish_namespace" request_id: uint64 track_namespace: [ *MOQTByteString] number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 56: MOQTPublishNamespace definition 5.6.23. MOQTPublishNamespaceOk MOQTPublishNamespaceOk = { type: "publish_namespace_ok" request_id: uint64 } Figure 57: MOQTPublishNamespaceOk definition Pardue, et al. Expires 11 July 2026 [Page 25] Internet-Draft MoQ qlog event definitions January 2026 5.6.24. MOQTPublishNamespaceError MOQTPublishNamespaceError = { type: "publish_namespace_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 58: MOQTPublishNamespaceError definition 5.6.25. MOQTPublishNamespaceDone MOQTPublishNamespaceDone = { type: "publish_namespace_done" track_namespace: [ *MOQTByteString] } Figure 59: MOQTPublishNamespaceDone definition 5.6.26. MOQTPublishNamespaceCancel MOQTPublishNamespaceCancel = { type: "publish_namespace_cancel" track_namespace: [ *MOQTByteString] error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 60: MOQTPublishNamespaceCancel definition 5.6.27. MOQTSubscribeNamespace MOQTSubscribeNamespace = { type: "subscribe_namespace" request_id: uint64 track_namespace_prefix: [ *MOQTByteString] number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 61: MOQTSubscribeNamespace definition 5.6.28. MOQTSubscribeNamespaceOk Pardue, et al. Expires 11 July 2026 [Page 26] Internet-Draft MoQ qlog event definitions January 2026 MOQTSubscribeNamespaceOk = { type: "subscribe_namespace_ok" request_id: uint64 } Figure 62: MOQTSubscribeNamespaceOk definition 5.6.29. MOQTSubscribeNamespaceError MOQTSubscribeNamespaceError = { type: "subscribe_namespace_error" request_id: uint64 error_code: uint64 ? reason: text ? reason_bytes: hexstring } Figure 63: MOQTSubscribeNamespaceError definition 5.6.30. MOQTUnsubscribeNamespace MOQTUnsubscribeNamespace = { type: "unsubscribe_namespace" track_namespace_prefix: [ *MOQTByteString] } Figure 64: MOQTUnsubscribeNamespace definition 5.7. MOQTExtensionHeader MOQTExtensionHeader = { header_type: uint64 ? header_value: uint64 ? header_length: uint64 ? payload: RawInfo } Figure 65: Extension Header definition 6. Security Considerations The security and privacy considerations discussed in [QLOG-MAIN] apply to this document as well. 7. IANA Considerations This document registers a new entry in the "qlog event schema URIs" registry (created in Section 15 of [QLOG-MAIN]). Pardue, et al. Expires 11 July 2026 [Page 27] Internet-Draft MoQ qlog event definitions January 2026 Event schema URI: urn:ietf:params:qlog:events:moqt Namespace moqt Event Types control_message_created, control_message_parsed, stream_type_set, object_datagram_created, object_datagram_parsed, subgroup_header_created, subgroup_header_parsed, subgroup_object_created, subgroup_object_parsed, fetch_header_created, fetch_header_parsed, fetch_object_created, fetch_object_parsed Description: Event definitions related to the MOQT protocol. Reference: This Document 8. Normative References [CDDL] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data Definition Language (CDDL): A Notational Convention to Express Concise Binary Object Representation (CBOR) and JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610, June 2019, . [MOQT] Nandakumar, S., Vasiliev, V., Swett, I., and A. Frindell, "Media over QUIC Transport", Work in Progress, Internet- Draft, draft-ietf-moq-transport-15, 20 October 2025, . [QLOG-MAIN] Marx, R., Niccolini, L., Seemann, M., and L. Pardue, "qlog: Structured Logging for Network Protocols", Work in Progress, Internet-Draft, draft-ietf-quic-qlog-main- schema-13, 20 October 2025, . [QLOG-QUIC] Marx, R., Niccolini, L., Seemann, M., and L. Pardue, "QUIC event definitions for qlog", Work in Progress, Internet- Draft, draft-ietf-quic-qlog-quic-events-12, 20 October 2025, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Pardue, et al. Expires 11 July 2026 [Page 28] Internet-Draft MoQ qlog event definitions January 2026 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . Acknowledgments Thanks to Lorenzo Miniero, Sujay Patel, and Aman Sharm for feedback and contributions to this document. Authors' Addresses Lucas Pardue Cloudflare Email: lucas@lucaspardue.com Mathis Engelbart Technical University of Munich Email: mathis.engelbart@gmail.com Aman Sharma Meta Email: amsharma@meta.com Pardue, et al. Expires 11 July 2026 [Page 29]