Media Over QUIC L. Pardue Internet-Draft Cloudflare Intended status: Informational M. Engelbart Expires: 21 March 2027 Technical University of Munich A. Sharma Meta 17 September 2026 MoQ qlog event definitions draft-pardue-moq-qlog-moq-events-08 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 21 March 2027 [Page 1] Internet-Draft MoQ qlog event definitions September 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 21 March 2027. 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 . . . . . . . . . . . . . . . . . 6 3. Event Schema Definition . . . . . . . . . . . . . . . . . . . 6 3.1. Draft Event Schema Identification . . . . . . . . . . . . 6 4. MOQT Events . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.1. control_message_created . . . . . . . . . . . . . . . . . 7 4.2. control_message_parsed . . . . . . . . . . . . . . . . . 8 4.3. stream_type_set . . . . . . . . . . . . . . . . . . . . . 8 4.4. object_datagram_created . . . . . . . . . . . . . . . . . 9 4.5. object_datagram_parsed . . . . . . . . . . . . . . . . . 9 4.6. padding_datagram_created . . . . . . . . . . . . . . . . 10 4.7. padding_datagram_parsed . . . . . . . . . . . . . . . . . 10 4.8. subgroup_header_created . . . . . . . . . . . . . . . . . 11 4.9. subgroup_header_parsed . . . . . . . . . . . . . . . . . 11 4.10. subgroup_object_created . . . . . . . . . . . . . . . . . 12 4.11. subgroup_object_parsed . . . . . . . . . . . . . . . . . 12 4.12. fetch_header_created . . . . . . . . . . . . . . . . . . 13 4.13. fetch_header_parsed . . . . . . . . . . . . . . . . . . . 13 4.14. fetch_object_created . . . . . . . . . . . . . . . . . . 13 4.15. fetch_object_parsed . . . . . . . . . . . . . . . . . . . 14 5. MOQT Data Type Definitions . . . . . . . . . . . . . . . . . 15 5.1. Owner . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5.2. MOQTLocation . . . . . . . . . . . . . . . . . . . . . . 15 5.3. MOQTSubscriptionFilter . . . . . . . . . . . . . . . . . 15 Pardue, et al. Expires 21 March 2027 [Page 2] Internet-Draft MoQ qlog event definitions September 2026 5.4. MOQTAliasType . . . . . . . . . . . . . . . . . . . . . . 15 5.5. MOQTSetupOption . . . . . . . . . . . . . . . . . . . . . 15 5.5.1. MOQTAuthoritySetupOption . . . . . . . . . . . . . . 16 5.5.2. MOQTPathSetupOption . . . . . . . . . . . . . . . . . 16 5.5.3. MOQTMaxAuthTokenCacheSizeSetupOption . . . . . . . . 16 5.5.4. MOQTAuthorizationTokenSetupOption . . . . . . . . . . 16 5.5.5. MOQTImplementationSetupOption . . . . . . . . . . . . 17 5.5.6. MOQTUnknownSetupOption . . . . . . . . . . . . . . . 17 5.6. MOQTParameter . . . . . . . . . . . . . . . . . . . . . . 17 5.6.1. MOQTAuthorizationTokenParameter . . . . . . . . . . . 18 5.6.2. MOQTSubgroupDeliveryTimeoutParameter . . . . . . . . 18 5.6.3. MOQTObjectDeliveryTimeoutParameter . . . . . . . . . 18 5.6.4. MOQTFillTimeoutParameter . . . . . . . . . . . . . . 19 5.6.5. MOQTRendezvousTimeoutParameter . . . . . . . . . . . 19 5.6.6. MOQTSubscriberPriorityParameter . . . . . . . . . . . 19 5.6.7. MOQTGroupOrderParameter . . . . . . . . . . . . . . . 19 5.6.8. MOQTSubscriptionFilterParameter . . . . . . . . . . . 19 5.6.9. MOQTExpiresParameter . . . . . . . . . . . . . . . . 19 5.6.10. MOQTLargestObjectParameter . . . . . . . . . . . . . 20 5.6.11. MOQTForwardParameter . . . . . . . . . . . . . . . . 20 5.6.12. MOQTNewGroupRequestParameter . . . . . . . . . . . . 20 5.6.13. MOQTTrackNamespacePrefixParameter . . . . . . . . . . 20 5.6.14. MOQTUnknownParameter . . . . . . . . . . . . . . . . 20 5.7. MOQTByteString . . . . . . . . . . . . . . . . . . . . . 21 5.8. MOQTControlMessage . . . . . . . . . . . . . . . . . . . 21 5.8.1. MOQTSetupMessage . . . . . . . . . . . . . . . . . . 22 5.8.2. MOQTGoaway . . . . . . . . . . . . . . . . . . . . . 22 5.8.3. MOQTRequestOk . . . . . . . . . . . . . . . . . . . . 22 5.8.4. MOQTRequestError . . . . . . . . . . . . . . . . . . 23 5.8.5. MOQTSubscribe . . . . . . . . . . . . . . . . . . . . 23 5.8.6. MOQTSubscribeOk . . . . . . . . . . . . . . . . . . . 23 5.8.7. MOQTRequestUpdate . . . . . . . . . . . . . . . . . . 24 5.8.8. MOQTPublish . . . . . . . . . . . . . . . . . . . . . 24 5.8.9. MOQTPublishDone . . . . . . . . . . . . . . . . . . . 24 5.8.10. MOQTFetch . . . . . . . . . . . . . . . . . . . . . . 25 5.8.11. MOQTFetchOk . . . . . . . . . . . . . . . . . . . . . 25 5.8.12. MOQTTrackStatus . . . . . . . . . . . . . . . . . . . 25 5.8.13. MOQTPublishNamespace . . . . . . . . . . . . . . . . 26 5.8.14. MOQTNamespace . . . . . . . . . . . . . . . . . . . . 26 5.8.15. MOQTNamespaceDone . . . . . . . . . . . . . . . . . . 26 5.8.16. MOQTSubscribeNamespace . . . . . . . . . . . . . . . 26 5.8.17. MOQTSubscribeTracks . . . . . . . . . . . . . . . . . 27 5.8.18. MOQTPublishBlocked . . . . . . . . . . . . . . . . . 27 5.9. MOQTProperty . . . . . . . . . . . . . . . . . . . . . . 27 6. Security Considerations . . . . . . . . . . . . . . . . . . . 27 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28 8. Normative References . . . . . . . . . . . . . . . . . . . . 28 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 29 Pardue, et al. Expires 21 March 2027 [Page 3] Internet-Draft MoQ qlog event definitions September 2026 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 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. Pardue, et al. Expires 21 March 2027 [Page 4] Internet-Draft MoQ qlog event definitions September 2026 +===============================+============+==============+ | 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:padding_datagram_created | Core | Section 4.6 | +-------------------------------+------------+--------------+ | moqt:padding_datagram_parsed | Core | Section 4.7 | +-------------------------------+------------+--------------+ | moqt:subgroup_header_created | Core | Section 4.8 | +-------------------------------+------------+--------------+ | moqt:subgroup_header_parsed | Core | Section 4.9 | +-------------------------------+------------+--------------+ | moqt:subgroup_object_created | Core | Section 4.10 | +-------------------------------+------------+--------------+ | moqt:subgroup_object_parsed | Core | Section 4.11 | +-------------------------------+------------+--------------+ | moqt:fetch_header_created | Core | Section 4.12 | +-------------------------------+------------+--------------+ | moqt:fetch_header_parsed | Core | Section 4.13 | +-------------------------------+------------+--------------+ | moqt:fetch_object_created | Core | Section 4.14 | +-------------------------------+------------+--------------+ | moqt:fetch_object_parsed | Core | Section 4.15 | +-------------------------------+------------+--------------+ Table 1: MOQT Events 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. Pardue, et al. Expires 21 March 2027 [Page 5] Internet-Draft MoQ qlog event definitions September 2026 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. 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. Pardue, et al. Expires 21 March 2027 [Page 6] Internet-Draft MoQ qlog event definitions September 2026 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 $$ CDDL "group socket" syntax, as also described in [QLOG-MAIN]. MOQTEventData = MOQTControlMessageCreated / MOQTControlMessageParsed / MOQTStreamTypeSet / MOQTObjectDatagramCreated / MOQTObjectDatagramParsed / MOQTPaddingDatagramCreated / MOQTPaddingDatagramParsed / MOQTSubgroupHeaderCreated / MOQTSubgroupHeaderParsed / MOQTSubgroupObjectCreated / MOQTSubgroupObjectParsed / MOQTFetchHeaderCreated / MOQTFetchHeaderParsed / MOQTFetchObjectCreated / MOQTFetchObjectParsed $ProtocolEventData /= MOQTEventData Figure 1: MOQTEventData definition and ProtocolEventData extension MOQT events are logged when a certain condition happens at the application layer, and there isn't always a one to one mapping between HTTP and QUIC events. The exchange of data between the HTTP and QUIC layer is logged via the "stream_data_moved" and "datagram_data_moved" events in [QLOG-QUIC]. The concrete MOQT event types are further defined below, their type identifier is the heading name. 4.1. control_message_created The control_message_created event is emitted when a control message is created. It has Core importance level. Pardue, et al. Expires 21 March 2027 [Page 7] Internet-Draft MoQ qlog event definitions September 2026 The definition of control message content is in Section 5.8. MOQTControlMessageCreated = { stream_id: uint64 ? length: uint16 message: $MOQTControlMessage ? raw: RawInfo * $$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 5.8. MOQTControlMessageParsed = { stream_id: uint64 ? length: uint16 message: $MOQTControlMessage ? raw: RawInfo * $$moqt-controlmessageparsed-extension } Figure 3: MOQTControlMessageParsed definition 4.3. stream_type_set The stream_type_set event conveys when a MOQT stream type becomes known. It has Base importance level. MOQTStreamTypeSet = { ? owner: Owner stream_id: uint64 stream_type: $MOQTStreamType * $$moqt-streamtypeset-extension } $MOQTStreamType /= "control" / "subgroup_header" / "fetch_header" / "padding" Pardue, et al. Expires 21 March 2027 [Page 8] Internet-Draft MoQ qlog event definitions September 2026 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. If the publisher_priority is absent, it means that the object inherits the Publisher Priority specified in the control message that established the subscription. MOQTObjectDatagramCreated = { track_alias: uint64 group_id: uint64 ? object_id: uint64 ? publisher_priority: uint8 ? properties_length: uint64 ? properties: [* MOQTProperty] ? object_status: uint64 ? object_payload: RawInfo end_of_group: bool * $$moqt-objectdatagramcreated-extension } Figure 5: MOQTObjectDatagramCreated definition 4.5. object_datagram_parsed The object_datagram_parsed event is emitted when the OBJECT_DATAGRAM message is parsed. It has Core importance level. If the publisher_priority is absent, it means that the object inherits the Publisher Priority specified in the control message that established the subscription. Pardue, et al. Expires 21 March 2027 [Page 9] Internet-Draft MoQ qlog event definitions September 2026 MOQTObjectDatagramParsed = { track_alias: uint64 group_id: uint64 ? object_id: uint64 ? publisher_priority: uint8 ? properties_length: uint64 ? properties: [* MOQTProperty] ? object_status: uint64 ? object_payload: RawInfo end_of_group: bool * $$moqt-objectdatagramparsed-extension } Figure 6: MOQTObjectDatagramParsed definition 4.6. padding_datagram_created The padding_datagram_created event is emitted when a padding datagram is created. It has Core importance level. Padding datagrams contain no application data. MOQTPaddingDatagramCreated = { padding_length: uint64 * $$moqt-paddingdatagramcreated-extension } Figure 7: MOQTPaddingDatagramCreated definition 4.7. padding_datagram_parsed The padding_datagram_parsed event is emitted when a padding datagram is parsed. It has Core importance level. Padding datagrams contain no application data. MOQTPaddingDatagramParsed = { padding_length: uint64 * $$moqt-paddingdatagramparsed-extension } Figure 8: MOQTPaddingDatagramParsed definition Pardue, et al. Expires 21 March 2027 [Page 10] Internet-Draft MoQ qlog event definitions September 2026 4.8. 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 5 bits in the type value to convey various properties. The subgroup_header_created event conveys these as explicit fields, such as contains_end_of_group. If the publisher_priority is absent, it means that the subgroup inherits the Publisher Priority specified in the control message that established the subscription. MOQTSubgroupHeaderCreated = { stream_id: uint64 track_alias: uint64 group_id: uint64 subgroup_id_mode: uint8 ? subgroup_id: uint64 ? publisher_priority: uint8 contains_end_of_group: bool properties_present: bool * $$moqt-subgroupheadercreated-extension } Figure 9: MOQTSubgroupHeaderCreated definition 4.9. subgroup_header_parsed The subgroup_header_parsed event is emitted when the SUBGROUP_HEADER is parsed. It has Core importance level. The SUBGROUP_HEADER object in MoQT uses 5 bits in the type value to convey various properties. The subgroup_header_created event conveys these as explicit fields, such as contains_end_of_group. If the publisher_priority is absent, it means that the subgroup inherits the Publisher Priority specified in the control message that established the subscription. Pardue, et al. Expires 21 March 2027 [Page 11] Internet-Draft MoQ qlog event definitions September 2026 MOQTSubgroupHeaderParsed = { stream_id: uint64 track_alias: uint64 group_id: uint64 subgroup_id_mode: uint8 ? subgroup_id: uint64 ? publisher_priority: uint8 contains_end_of_group: bool properties_present: bool * $$moqt-subgroupheaderparsed-extension } Figure 10: MOQTSubgroupHeaderParsed definition 4.10. 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 object_id_delta: uint64 ? properties: [* MOQTProperty] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-subgroupobjectcreated-extension } Figure 11: MOQTSubgroupObjectCreated definition 4.11. subgroup_object_parsed The subgroup_object_parsed event is emitted when a subgroup object is parsed. It has Core importance level. MOQTSubgroupObjectParsed = { stream_id: uint64 object_id_delta: uint64 ? properties: [* MOQTProperty] object_payload_length: uint64 ? object_status: uint64 ? object_payload: RawInfo * $$moqt-subgroupobjectparsed-extension } Pardue, et al. Expires 21 March 2027 [Page 12] Internet-Draft MoQ qlog event definitions September 2026 Figure 12: MOQTSubgroupObjectParsed definition 4.12. 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 * $$moqt-fetchheadercreated-extension } Figure 13: MOQTFetchHeaderCreated definition 4.13. fetch_header_parsed The fetch_header_parsed event is emitted when the FETCH_HEADER is parsed. It has Core importance level. MOQTFetchHeaderParsed = { stream_id: uint64 request_id: uint64 * $$moqt-fetchheaderparsed-extension } Figure 14: MOQTFetchHeaderParsed definition 4.14. fetch_object_created The fetch_object_created event is emitted when a fetch object is created. It has Core importance level. The FETCH object in MoQT uses serialization flags to encode various properties. The event conveys these as explicit fields, such as end_of_unknown_range. Pardue, et al. Expires 21 March 2027 [Page 13] Internet-Draft MoQ qlog event definitions September 2026 MOQTFetchObjectCreated = { stream_id: uint64 datagram: bool end_of_nonexistent_range: bool end_of_unknown_range: bool ? subgroup_id_bits: uint8 ? group_id_delta: uint64 ? subgroup_id: uint64 ? object_id_delta: uint64 ? publisher_priority: uint8 ? properties_length: uint64 ? properties: [* MOQTProperty] object_payload_length: uint64 ? object_payload: RawInfo * $$moqt-fetchobjectcreated-extension } Figure 15: MOQTFetchObjectCreated definition 4.15. fetch_object_parsed The fetch_object_parsed event is emitted when a fetch object is parsed. It has Core importance level. The FETCH object in MoQT uses serialization flags to encode various properties. The event conveys these as explicit fields, such as end_of_unknown_range. MOQTFetchObjectParsed = { stream_id: uint64 datagram: bool end_of_nonexistent_range: bool end_of_unknown_range: bool ? subgroup_id_bits: uint8 ? group_id_delta: uint64 ? subgroup_id: uint64 ? object_id_delta: uint64 ? publisher_priority: uint8 ? properties_length: uint64 ? properties: [* MOQTProperty] object_payload_length: uint64 ? object_payload: RawInfo * $$moqt-fetchobjectparsed-extension } Figure 16: MOQTFetchObjectParsed definition Pardue, et al. Expires 21 March 2027 [Page 14] Internet-Draft MoQ qlog event definitions September 2026 5. MOQT Data Type Definitions The following data type definitions can be used in MOQT events. 5.1. Owner Owner = "local" / "remote" Figure 17: Owner definition 5.2. MOQTLocation A Location, as defined in Section 1.4.2 of [MOQT] MOQTLocation = { group: uint64 object: uint64 } Figure 18: MOQTLocation definition 5.3. MOQTSubscriptionFilter A Subscription Filter, as defined in Section 5.1.2 of [MOQT] MOQTSubscriptionFilter = { filter_type: uint64 ? start_location: MOQTLocation ? end_group_delta: uint64 } Figure 19: MOQTSubscriptionFilter definition 5.4. MOQTAliasType $MOQTAliasType /= "delete" / "register" / "use_alias" / "use_value" Figure 20: MOQTAliasType definition 5.5. MOQTSetupOption The generic $MOQTSetupOption is defined here as a CDDL "type socket" extension point. It can be extended to support additional MOQT Setup Options. Pardue, et al. Expires 21 March 2027 [Page 15] Internet-Draft MoQ qlog event definitions September 2026 ; The MOQTSetupOption is any key-value map (e.g., JSON object) $MOQTSetupOption /= { * text => any } Figure 21: MOQTSetupOption type socket definition MOQTBaseSetupOptions /= MOQTAuthoritySetupOption / MOQTPathSetupOption / MOQTMaxAuthTokenCacheSizeSetupOption / MOQTAuthorizationTokenSetupOption / MOQTImplementationSetupOption / MOQTUnknownSetupOption $MOQTSetupOption /= MOQTBaseSetupOptions Figure 22: MOQTBaseSetupOptions definition 5.5.1. MOQTAuthoritySetupOption MOQTAuthoritySetupOption = { name: "authority" value: text } Figure 23: MOQTAuthoritySetupOption definition 5.5.2. MOQTPathSetupOption MOQTPathSetupOption = { name: "path" value: text } Figure 24: MOQTPathSetupOption definition 5.5.3. MOQTMaxAuthTokenCacheSizeSetupOption MOQTMaxAuthTokenCacheSizeSetupOption = { name: "max_auth_token_cache_size" value: uint64 } Figure 25: MOQTMaxAuthTokenCacheSizeSetupOption definition 5.5.4. MOQTAuthorizationTokenSetupOption Pardue, et al. Expires 21 March 2027 [Page 16] Internet-Draft MoQ qlog event definitions September 2026 MOQTAuthorizationTokenSetupOption = { name: "authorization_token" alias_type: $MOQTAliasType ? token_alias: uint64 ? token_type: uint64 ? token_value: RawInfo } Figure 26: MOQTAuthorizationTokenSetupOption definition 5.5.5. MOQTImplementationSetupOption MOQTImplementationSetupOption = { name: "implementation" value: text } Figure 27: MOQTImplementationSetupOption definition 5.5.6. MOQTUnknownSetupOption MOQTUnknownSetupOption = { name:"unknown" name_bytes: uint64 ? length: uint64 ? value: uint64 ? value_bytes: RawInfo } Figure 28: MOQTUnknownSetupOption definition 5.6. 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 29: MOQTParameter type socket definition Pardue, et al. Expires 21 March 2027 [Page 17] Internet-Draft MoQ qlog event definitions September 2026 MOQTBaseParameters /= MOQTAuthorizationTokenParameter / MOQTSubgroupDeliveryTimeoutParameter / MOQTObjectDeliveryTimeoutParameter / MOQTFillTimeoutParameter / MOQTRendezvousTimeoutParameter / MOQTSubscriberPriorityParameter / MOQTGroupOrderParameter / MOQTSubscriptionFilterParameter / MOQTExpiresParameter / MOQTLargestObjectParameter / MOQTForwardParameter / MOQTNewGroupRequestParameter / MOQTTrackNamespacePrefixParameter / MOQTUnknownParameter $MOQTParameter /= MOQTBaseParameters Figure 30: MOQTBaseParameters definition 5.6.1. MOQTAuthorizationTokenParameter MOQTAuthorizationTokenParameter = { name: "authorization_token" alias_type: $MOQTAliasType ? token_alias: uint64 ? token_type: uint64 ? token_value: RawInfo } Figure 31: MOQTAuthorizationTokenParameter definition 5.6.2. MOQTSubgroupDeliveryTimeoutParameter MOQTSubgroupDeliveryTimeoutParameter = { name: "subgroup_delivery_timeout" value: uint64 } Figure 32: MOQTSubgroupDeliveryTimeoutParameter definition 5.6.3. MOQTObjectDeliveryTimeoutParameter MOQTObjectDeliveryTimeoutParameter = { name: "object_delivery_timeout" value: uint64 } Figure 33: MOQTObjectDeliveryTimeoutParameter definition Pardue, et al. Expires 21 March 2027 [Page 18] Internet-Draft MoQ qlog event definitions September 2026 5.6.4. MOQTFillTimeoutParameter MOQTFillTimeoutParameter = { name: "fill_timeout" value: uint64 } Figure 34: MOQTFillTimeoutParameter definition 5.6.5. MOQTRendezvousTimeoutParameter MOQTRendezvousTimeoutParameter = { name: "rendezvous_timeout" value: uint64 } Figure 35: MOQTRendezvousTimeoutParameter definition 5.6.6. MOQTSubscriberPriorityParameter MOQTSubscriberPriorityParameter = { name: "subscriber_priority" value: uint64 } Figure 36: MOQTSubscriberPriorityParameter definition 5.6.7. MOQTGroupOrderParameter MOQTGroupOrderParameter = { name: "group_order" value: uint64 } Figure 37: MOQTGroupOrderParameter definition 5.6.8. MOQTSubscriptionFilterParameter MOQTSubscriptionFilterParameter = { name: "subscription_filter" value: MOQTSubscriptionFilter } Figure 38: MOQTSubscriptionFilterParameter definition 5.6.9. MOQTExpiresParameter Pardue, et al. Expires 21 March 2027 [Page 19] Internet-Draft MoQ qlog event definitions September 2026 MOQTExpiresParameter = { name: "expires" value: uint64 } Figure 39: MOQTExpiresParameter definition 5.6.10. MOQTLargestObjectParameter MOQTLargestObjectParameter = { name: "largest_object" value: MOQTLocation } Figure 40: MOQTLargestObjectParameter definition 5.6.11. MOQTForwardParameter MOQTForwardParameter = { name: "forward" value: uint64 } Figure 41: MOQTForwardParameter definition 5.6.12. MOQTNewGroupRequestParameter MOQTNewGroupRequestParameter = { name: "new_group_request" value: uint64 } Figure 42: MOQTNewGroupRequestParameter definition 5.6.13. MOQTTrackNamespacePrefixParameter MOQTTrackNamespacePrefixParameter = { name: "track_namespace_prefix" value: [ *MOQTByteString] } Figure 43: MOQTTrackNamespacePrefixParameter definition 5.6.14. MOQTUnknownParameter Pardue, et al. Expires 21 March 2027 [Page 20] Internet-Draft MoQ qlog event definitions September 2026 MOQTUnknownParameter = { name:"unknown" name_bytes: uint64 ? length: uint64 ? value: uint64 ? value_bytes: RawInfo } Figure 44: MOQTUnknownParameter definition 5.7. 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 45: MOQTByteString definition 5.8. 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 46: MOQTControlMessage type socket definition The MOQT control message types defined in this document are as follows: Pardue, et al. Expires 21 March 2027 [Page 21] Internet-Draft MoQ qlog event definitions September 2026 MOQTBaseControlMessages = MOQTSetupMessage / MOQTGoaway / MOQTRequestOk / MOQTRequestError / MOQTSubscribe / MOQTSubscribeOk / MOQTRequestUpdate / MOQTPublish / MOQTPublishDone / MOQTFetch / MOQTFetchOk / MOQTTrackStatus / MOQTPublishNamespace / MOQTNamespace / MOQTNamespaceDone / MOQTSubscribeNamespace / MOQTSubscribeTracks / MOQTPublishBlocked $MOQTControlMessage /= MOQTBaseControlMessages Figure 47: MOQTBaseControlMessages definition 5.8.1. MOQTSetupMessage MOQTSetupMessage = { type: "setup" ? setup_options: [* $MOQTSetupOption] } Figure 48: MOQTSetupMessage definition 5.8.2. MOQTGoaway MOQTGoaway = { type: "goaway" new_session_uri: RawInfo timeout: uint64 ? request_id : uint64 } Figure 49: MOQTGoaway definition 5.8.3. MOQTRequestOk Pardue, et al. Expires 21 March 2027 [Page 22] Internet-Draft MoQ qlog event definitions September 2026 MOQTRequestOk = { type: "request_ok" number_of_parameters: uint64 ? parameters: [* $MOQTParameter] ? track_properties: [* MOQTProperty] } Figure 50: MOQTRequestOk definition 5.8.4. MOQTRequestError MOQTRequestError = { type: "request_error" error_code: uint64 retry_interval: uint64 ? reason_phrase: text ? redirect: $MOQTRedirect } MOQTRedirect = { connect_uri: RawInfo track_namespace: [ *MOQTByteString] track_name: MOQTByteString } Figure 51: MOQTRequestError definition 5.8.5. MOQTSubscribe MOQTSubscribe = { type: "subscribe" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 52: MOQTSubscribe definition 5.8.6. MOQTSubscribeOk Pardue, et al. Expires 21 March 2027 [Page 23] Internet-Draft MoQ qlog event definitions September 2026 MOQTSubscribeOk = { type: "subscribe_ok" track_alias: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] ? track_properties: [* MOQTProperty] } Figure 53: MOQTSubscribeOk definition 5.8.7. MOQTRequestUpdate MOQTRequestUpdate = { type: "request_update" request_id: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 54: MOQTRequestUpdate definition 5.8.8. MOQTPublish MOQTPublish = { type: "publish" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString track_alias: uint64 number_of_parameters: uint64 ? parameters: [* $MOQTParameter] ? track_properties: [* MOQTProperty] } Figure 55: MOQTPublish definition 5.8.9. MOQTPublishDone MOQTPublishDone = { type: "publish_done" status_code: uint64 stream_count: uint64 ? reason_phrase: text } Figure 56: MOQTPublishDone definition Pardue, et al. Expires 21 March 2027 [Page 24] Internet-Draft MoQ qlog event definitions September 2026 5.8.10. MOQTFetch MOQTFetch = { type: "fetch" request_id: uint64 fetch_type: $MOQTFetchType ? standalone_fetch: $MOQTStandaloneFetch ? joining_fetch: $MOQTJoiningFetch number_of_parameters: uint64 ? 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 57: MOQTFetch definition 5.8.11. MOQTFetchOk MOQTFetchOk = { type: "fetch_ok" end_of_track: uint8 end_location: MOQTLocation number_of_parameters: uint64 ? parameters: [* $MOQTParameter] ? track_properties: [* MOQTProperty] } Figure 58: MOQTFetchOk definition 5.8.12. MOQTTrackStatus Pardue, et al. Expires 21 March 2027 [Page 25] Internet-Draft MoQ qlog event definitions September 2026 MOQTTrackStatus = { type: "track_status" request_id: uint64 track_namespace: [ *MOQTByteString] track_name: MOQTByteString number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 59: MOQTTrackStatus definition 5.8.13. MOQTPublishNamespace MOQTPublishNamespace = { type: "publish_namespace" request_id: uint64 track_namespace: [ *MOQTByteString] number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 60: MOQTPublishNamespace definition 5.8.14. MOQTNamespace MOQTNamespace = { type: "namespace" track_namespace_suffix: [ *MOQTByteString] } Figure 61: MOQTNamespace definition 5.8.15. MOQTNamespaceDone MOQTNamespaceDone = { type: "namespace_done" track_namespace_suffix: [ *MOQTByteString] } Figure 62: MOQTNamespaceDone definition 5.8.16. MOQTSubscribeNamespace Pardue, et al. Expires 21 March 2027 [Page 26] Internet-Draft MoQ qlog event definitions September 2026 MOQTSubscribeNamespace = { type: "subscribe_namespace" request_id: uint64 track_namespace_prefix: [ *MOQTByteString] number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 63: MOQTSubscribeNamespace definition 5.8.17. MOQTSubscribeTracks MOQTSubscribeTracks = { type: "subscribe_tracks" request_id: uint64 track_namespace_prefix: [ *MOQTByteString] number_of_parameters: uint64 ? parameters: [* $MOQTParameter] } Figure 64: MOQTSubscribeTracks definition 5.8.18. MOQTPublishBlocked MOQTPublishBlocked = { type: "publish_blocked" track_namespace_suffix: [ *MOQTByteString] track_name: MOQTByteString } Figure 65: MOQTPublishBlocked definition 5.9. MOQTProperty MOQTProperty = { type: uint64 ? value: uint64 ? length: uint64 ? value_bytes: RawInfo } Figure 66: Property definition 6. Security Considerations The security and privacy considerations discussed in [QLOG-MAIN] apply to this document as well. Pardue, et al. Expires 21 March 2027 [Page 27] Internet-Draft MoQ qlog event definitions September 2026 7. IANA Considerations This document registers a new entry in the "qlog event schema URIs" registry (created in Section 15 of [QLOG-MAIN]). 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, padding_datagram_created, padding_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-21, 8 September 2026, . [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-14, 6 July 2026, . Pardue, et al. Expires 21 March 2027 [Page 28] Internet-Draft MoQ qlog event definitions September 2026 [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-13, 6 July 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, . 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 21 March 2027 [Page 29]