Internet-Draft HTTP/3 and QPACK qlog event definitions August 2022
Marx, et al. Expires 4 March 2023 [Page]
Workgroup:
QUIC
Internet-Draft:
draft-ietf-quic-qlog-h3-events-02
Published:
Intended Status:
Standards Track
Expires:
Authors:
R. Marx
KU Leuven
L. Niccolini, Ed.
Facebook
M. Seemann, Ed.
Protocol Labs

HTTP/3 and QPACK qlog event definitions

Abstract

This document describes concrete qlog event definitions and their metadata for HTTP/3 and QPACK-related events. These events can then be embedded in the higher level schema defined in [QLOG-MAIN].

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 4 March 2023.

Table of Contents

1. Introduction

This document describes the values of the qlog name ("category" + "event") and "data" fields and their semantics for the HTTP/3 and QPACK protocols. This document is based on draft-34 of the HTTP/3 I-D [QUIC-HTTP] and draft-21 of the QPACK I-D [QUIC-QPACK]. QUIC events are defined in a separate document [QLOG-QUIC].

Feedback and discussion are welcome at https://github.com/quicwg/qlog. Readers are advised to refer to the "editor's draft" at that URL for an up-to-date version of this document.

Concrete examples of integrations of this schema in various programming languages can be found at https://github.com/quiclog/qlog/.

1.1. Notational Conventions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

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].

2. Overview

This document describes the values of the qlog "name" ("category" + "event") and "data" fields and their semantics for the HTTP/3 and QPACK protocols.

This document assumes the usage of the encompassing main qlog schema defined in [QLOG-MAIN]. Each subsection below defines a separate category (for example http, qpack) and each subsubsection is an event type (for example frame_created).

For each event type, its importance and data definition is laid out, often accompanied by possible values for the optional "trigger" field. For the definition and semantics of "importance" and "trigger", see the main schema document.

Most of the complex datastructures, enums and re-usable definitions are grouped together on the bottom of this document for clarity.

2.1. 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 HTTP/3 connection. 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).

3. HTTP/3 and QPACK event definitions

Each subheading in this section is a qlog event category, while each sub-subheading is a qlog event type.

For example, for the following two items, we have the category "http" and event type "parameters_set", resulting in a concatenated qlog "name" field value of "http:parameters_set".

3.1. http

Note: like all category values, the "http" category is written in lowercase.

3.1.1. parameters_set

Importance: Base

This event contains HTTP/3 and QPACK-level settings, mostly those received from the HTTP/3 SETTINGS frame. All these parameters are typically set once and never change. However, they are typically set at different times during the connection, so there can be several instances of this event with different fields set.

Note that some settings have two variations (one set locally, one requested by the remote peer). This is reflected in the "owner" field. As such, this field MUST be correct for all settings included a single event instance. If you need to log settings from two sides, you MUST emit two separate event instances.

Note: we use the CDDL unwrap operator (~) here to make HTTPParameters into a re-usable list of fields. The unwrap operator copies the fields from the referenced type into the target type directly, extending the target with the unwrapped fields. TODO: explain this better + provide reference and maybe an example.

Definition:

HTTPParametersSet = {
    ? owner: Owner

    ~HTTPParameters

    ; qlog-specific
    ; indicates whether this implementation waits for a SETTINGS
    ; frame before processing requests
    ? waits_for_settings: bool
}

HTTPParameters = {
    ? max_header_list_size: uint64
    ? max_table_capacity: uint64
    ? blocked_streams_count: uint64

    ; additional settings for grease and extensions
    * text => uint64
}
Figure 1: HTTPParametersSet definition

Note: enabling server push is not explicitly done in HTTP/3 by use of a setting or parameter. Instead, it is communicated by use of the MAX_PUSH_ID frame, which should be logged using the frame_created and frame_parsed events below.

Additionally, this event can contain any number of unspecified fields. This is to reflect setting of for example unknown (greased) settings or parameters of (proprietary) extensions.

3.1.2. parameters_restored

Importance: Base

When using QUIC 0-RTT, HTTP/3 clients are expected to remember and reuse the server's SETTINGs from the previous connection. This event is used to indicate which HTTP/3 settings were restored and to which values when utilizing 0-RTT.

Definition:

HTTPParametersRestored = {

    ~HTTPParameters

}
Figure 2: HTTPParametersRestored definition

Note that, like for parameters_set above, this event can contain any number of unspecified fields to allow for additional and custom settings.

3.1.3. stream_type_set

Importance: Base

Emitted when a stream's type becomes known. This is typically when a stream is opened and the stream's type indicator is sent or received.

Note: most of this information can also be inferred by looking at a stream's id, since id's are strictly partitioned at the QUIC level. Even so, this event has a "Base" importance because it helps a lot in debugging to have this information clearly spelled out.

Definition:

HTTPStreamTypeSet = {
    ? owner: Owner
    stream_id: uint64

    ? old: HTTPStreamType
    new: HTTPStreamType

    ; only when new === "push"
    ? associated_push_id: uint64
}

HTTPStreamType =  "data" /
                  "control" /
                  "push" /
                  "reserved" /
                  "qpack_encode" /
                  "qpack_decode"
Figure 3: HTTPStreamTypeSet definition

3.1.4. frame_created

Importance: Core

HTTP equivalent to the packet_sent event. This event is emitted when the HTTP/3 framing actually happens. Note: this is not necessarily the same as when the HTTP/3 data is passed on to the QUIC layer. For that, see the "data_moved" event in [QLOG-QUIC].

Definition:

HTTPFrameCreated = {
    stream_id: uint64
    ? length: uint64
    frame: HTTPFrame
    ? raw: RawInfo
}
Figure 4: HTTPFrameCreated definition

Note: in HTTP/3, DATA frames can have arbitrarily large lengths to reduce frame header overhead. As such, DATA frames can span many QUIC packets and can be created in a streaming fashion. In this case, the frame_created event is emitted once for the frame header, and further streamed data is indicated using the data_moved event.

3.1.5. frame_parsed

Importance: Core

HTTP equivalent to the packet_received event. This event is emitted when we actually parse the HTTP/3 frame. Note: this is not necessarily the same as when the HTTP/3 data is actually received on the QUIC layer. For that, see the "data_moved" event in [QLOG-QUIC].

Definition:

HTTPFrameParsed = {
    stream_id: uint64
    ? length: uint64
    frame: HTTPFrame
    ? raw: RawInfo
}
Figure 5: HTTPFrameParsed definition

Note: in HTTP/3, DATA frames can have arbitrarily large lengths to reduce frame header overhead. As such, DATA frames can span many QUIC packets and can be processed in a streaming fashion. In this case, the frame_parsed event is emitted once for the frame header, and further streamed data is indicated using the data_moved event.

3.1.6. push_resolved

Importance: Extra

This event is emitted when a pushed resource is successfully claimed (used) or, conversely, abandoned (rejected) by the application on top of HTTP/3 (e.g., the web browser). This event is added to help debug problems with unexpected PUSH behaviour, which is commonplace with HTTP/2.

Definition:

HTTPPushResolved = {
    ? push_id: uint64

    ; in case this is logged from a place that does not have access
    ; to the push_id
    ? stream_id: uint64

    decision: HTTPPushDecision
}

HTTPPushDecision = "claimed" / "abandoned"
Figure 6: HTTPPushResolved definition

3.2. qpack

Note: like all category values, the "qpack" category is written in lowercase.

The QPACK events mainly serve as an aid to debug low-level QPACK issues. The higher-level, plaintext header values SHOULD (also) be logged in the http.frame_created and http.frame_parsed event data (instead).

Note: qpack does not have its own parameters_set event. This was merged with http.parameters_set for brevity, since qpack is a required extension for HTTP/3 anyway. Other HTTP/3 extensions MAY also log their SETTINGS fields in http.parameters_set or MAY define their own events.

3.2.1. state_updated

Importance: Base

This event is emitted when one or more of the internal QPACK variables changes value. Note that some variables have two variations (one set locally, one requested by the remote peer). This is reflected in the "owner" field. As such, this field MUST be correct for all variables included a single event instance. If you need to log settings from two sides, you MUST emit two separate event instances.

Definition:

QPACKStateUpdate = {
    owner: Owner
    ? dynamic_table_capacity: uint64

    ; effective current size, sum of all the entries
    ? dynamic_table_size: uint64
    ? known_received_count: uint64
    ? current_insert_count: uint64
}
Figure 7: QPACKStateUpdate definition

3.2.2. stream_state_updated

Importance: Core

This event is emitted when a stream becomes blocked or unblocked by header decoding requests or QPACK instructions.

Note: This event is of "Core" importance, as it might have a large impact on HTTP/3's observed performance.

Definition:

QPACKStreamStateUpdate = {
    stream_id: uint64
    ; streams are assumed to start "unblocked"
    ; until they become "blocked"
    state: QPACKStreamState
}

QPACKStreamState = "blocked" / "unblocked"
Figure 8: QPACKStreamStateUpdate definition

3.2.3. dynamic_table_updated

Importance: Extra

This event is emitted when one or more entries are inserted or evicted from QPACK's dynamic table.

Definition:

QPACKDynamicTableUpdate = {
    ; local = the encoder's dynamic table
    ; remote = the decoder's dynamic table
    owner: Owner

    update_type: QPACKDynamicTableUpdateType
    entries: [+ QPACKDynamicTableEntry]
}

QPACKDynamicTableUpdateType = "inserted" / "evicted"

QPACKDynamicTableEntry = {
    index: uint64
    ? name: text / hexstring
    ? value: text / hexstring
}
Figure 9: QPACKDynamicTableUpdate definition

3.2.4. headers_encoded

Importance: Base

This event is emitted when an uncompressed header block is encoded successfully.

Note: this event has overlap with http.frame_created for the HeadersFrame type. When outputting both events, implementers MAY omit the "headers" field in this event.

Definition:

QPACKHeadersEncoded = {
    ? stream_id: uint64
    ? headers: [+ HTTPField]

    block_prefix: QPACKHeaderBlockPrefix
    header_block: [+ QPACKHeaderBlockRepresentation]

    ? length: uint
    ? raw: hexstring
}
Figure 10: QPACKHeadersEncoded definition

3.2.5. headers_decoded

Importance: Base

This event is emitted when a compressed header block is decoded successfully.

Note: this event has overlap with http.frame_parsed for the HeadersFrame type. When outputting both events, implementers MAY omit the "headers" field in this event.

Definition:

QPACKHeadersDecoded = {
    ? stream_id: uint64
    ? headers: [+ HTTPField]

    block_prefix: QPACKHeaderBlockPrefix
    header_block: [+ QPACKHeaderBlockRepresentation]

    ? length: uint32
    ? raw: hexstring
}
Figure 11: QPACKHeadersDecoded definition

3.2.6. instruction_created

Importance: Base

This event is emitted when a QPACK instruction (both decoder and encoder) is created and added to the encoder/decoder stream.

Definition:

QPACKInstructionCreated = {
    ; see definition in appendix
    instruction: QPACKInstruction
    ? length: uint32
    ? raw: hexstring
}
Figure 12: QPACKInstructionCreated definition

Note: encoder/decoder semantics and stream_id's are implicit in either the instruction types or can be logged via other events (e.g., http.stream_type_set)

3.2.7. instruction_parsed

Importance: Base

This event is emitted when a QPACK instruction (both decoder and encoder) is read from the encoder/decoder stream.

Definition:

QPACKInstructionParsed = {
    ; see QPACKInstruction definition in appendix
    instruction: QPACKInstruction

    ? length: uint32
    ? raw: hexstring
}
Figure 13: QPACKInstructionParsed definition

Note: encoder/decoder semantics and stream_id's are implicit in either the instruction types or can be logged via other events (e.g., http.stream_type_set)

4. Security Considerations

TBD

5. IANA Considerations

TBD

6. References

6.1. 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, , <https://www.rfc-editor.org/rfc/rfc8610>.
[QLOG-MAIN]
Marx, R., Ed., Niccolini, L., Ed., and M. Seemann, Ed., "Main logging schema for qlog", Work in Progress, Internet-Draft, draft-ietf-quic-qlog-main-schema-03, <https://datatracker.ietf.org/doc/html/draft-ietf-quic-qlog-main-schema-03>.
[QLOG-QUIC]
Marx, R., Ed., Niccolini, L., Ed., and M. Seemann, Ed., "QUIC event definitions for qlog", Work in Progress, Internet-Draft, draft-ietf-quic-qlog-quic-events-02, <https://datatracker.ietf.org/doc/html/draft-ietf-quic-qlog-quic-events-02>.
[QUIC-HTTP]
Bishop, M., Ed., "Hypertext Transfer Protocol Version 3 (HTTP/3)", Work in Progress, Internet-Draft, draft-ietf-quic-http-latest, <https://datatracker.ietf.org/doc/html/draft-ietf-quic-http-latest>.
[QUIC-QPACK]
Krasic, C., Bishop, M., and A. Frindell, Ed., "QPACK: Header Compression for HTTP over QUIC", Work in Progress, Internet-Draft, draft-ietf-quic-qpack-latest, <https://datatracker.ietf.org/doc/html/draft-ietf-quic-qpack-latest>.

6.2. Informative References

[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/rfc/rfc2119>.

Appendix A. HTTP/3 data field definitions

A.1. ProtocolEventBody extension

We extend the $ProtocolEventBody extension point defined in [QLOG-MAIN] with the HTTP/3 protocol events defined in this document.

HTTPEvents = HTTPParametersSet / HTTPParametersRestored /
             HTTPStreamTypeSet / HTTPFrameCreated /
             HTTPFrameParsed / HTTPPushResolved

$ProtocolEventBody /= HTTPEvents
Figure 14: HTTPEvents definition and ProtocolEventBody extension

A.2. Owner

Owner = "local" / "remote"
Figure 15: Owner definition

A.3. HTTP/3 Frames

HTTPFrame =  HTTPDataFrame /
             HTTPHeadersFrame /
             HTTPCancelPushFrame /
             HTTPSettingsFrame /
             HTTPPushPromiseFrame /
             HTTPGoawayFrame /
             HTTPMaxPushIDFrame /
             HTTPReservedFrame /
             UnknownFrame
Figure 16: HTTPFrame definition

A.3.1. DataFrame

HTTPDataFrame = {
    frame_type: "data"
    ? raw: hexstring
}
Figure 17: HTTPDataFrame definition

A.3.2. HeadersFrame

This represents an uncompressed, plaintext HTTP Headers frame (e.g., no QPACK compression is applied).

For example:

headers: [
  {
    "name": ":path",
    "value": "/"
  },
  {
    "name": ":method",
    "value": "GET"
  },
  {
    "name": ":authority",
    "value": "127.0.0.1:4433"
  },
  {
    "name": ":scheme",
    "value": "https"
  }
]
Figure 18: HTTPHeadersFrame example
HTTPHeadersFrame = {
    frame_type: "headers"
    headers: [* HTTPField]
}
Figure 19: HTTPHeadersFrame definition
HTTPField = {
    name: text
    value: text
}
Figure 20: HTTPField definition

A.3.3. CancelPushFrame

HTTPCancelPushFrame = {
    frame_type: "cancel_push"
    push_id: uint64
}
Figure 21: HTTPCancelPushFrame definition

A.3.4. SettingsFrame

HTTPSettingsFrame = {
    frame_type: "settings"
    settings: [* HTTPSetting]
}

HTTPSetting = {
    name: text
    value: uint64
}
Figure 22: HTTPSettingsFrame definition

A.3.5. PushPromiseFrame

HTTPPushPromiseFrame = {
    frame_type: "push_promise"
    push_id: uint64
    headers: [* HTTPField]
}
Figure 23: HTTPPushPromiseFrame definition

A.3.6. GoAwayFrame

HTTPGoawayFrame = {
    frame_type: "goaway"

    ; Either stream_id or push_id.
    ; This is implicit from the sender of the frame
    id: uint64
}
Figure 24: HTTPGoawayFrame definition

A.3.7. MaxPushIDFrame

HTTPMaxPushIDFrame = {
    frame_type: "max_push_id"
    push_id: uint64
}
Figure 25: HTTPMaxPushIDFrame definition

A.3.8. ReservedFrame

HTTPReservedFrame = {
    frame_type: "reserved"

    ? length: uint64
}
Figure 26: HTTPReservedFrame definition

A.3.9. UnknownFrame

HTTP/3 qlog re-uses QUIC's UnknownFrame definition, since their values and usage overlaps. See [QLOG-QUIC].

A.4. ApplicationError

HTTPApplicationError =  "http_no_error" /
                        "http_general_protocol_error" /
                        "http_internal_error" /
                        "http_stream_creation_error" /
                        "http_closed_critical_stream" /
                        "http_frame_unexpected" /
                        "http_frame_error" /
                        "http_excessive_load" /
                        "http_id_error" /
                        "http_settings_error" /
                        "http_missing_settings" /
                        "http_request_rejected" /
                        "http_request_cancelled" /
                        "http_request_incomplete" /
                        "http_early_response" /
                        "http_connect_error" /
                        "http_version_fallback"
Figure 27: HTTPApplicationError definition

The HTTPApplicationError defines the general $ApplicationError definition in the qlog QUIC definition, see [QLOG-QUIC].

; ensure HTTP errors are properly validate in QUIC events as well
; e.g., QUIC's ConnectionClose Frame
$ApplicationError /= HTTPApplicationError

Appendix B. QPACK DATA type definitions

B.1. ProtocolEventBody extension

We extend the $ProtocolEventBody extension point defined in [QLOG-MAIN] with the QPACK protocol events defined in this document.

QPACKEvents = QPACKStateUpdate / QPACKStreamStateUpdate /
              QPACKDynamicTableUpdate / QPACKHeadersEncoded /
              QPACKHeadersDecoded / QPACKInstructionCreated /
              QPACKInstructionParsed

$ProtocolEventBody /= QPACKEvents
Figure 28: QPACKEvents definition and ProtocolEventBody extension

B.2. QPACK Instructions

Note: the instructions do not have explicit encoder/decoder types, since there is no overlap between the insturctions of both types in neither name nor function.

QPACKInstruction =  SetDynamicTableCapacityInstruction /
                    InsertWithNameReferenceInstruction /
                    InsertWithoutNameReferenceInstruction /
                    DuplicateInstruction /
                    SectionAcknowledgementInstruction /
                    StreamCancellationInstruction /
                    InsertCountIncrementInstruction
Figure 29: QPACKInstruction definition

B.2.1. SetDynamicTableCapacityInstruction

SetDynamicTableCapacityInstruction = {
    instruction_type: "set_dynamic_table_capacity"
    capacity: uint32
}
Figure 30: SetDynamicTableCapacityInstruction definition

B.2.2. InsertWithNameReferenceInstruction

InsertWithNameReferenceInstruction = {
    instruction_type: "insert_with_name_reference"
    table_type: QPACKTableType
    name_index: uint32
    huffman_encoded_value: bool
    ? value_length: uint32
    ? value: text
}
Figure 31: InsertWithNameReferenceInstruction definition

B.2.3. InsertWithoutNameReferenceInstruction

InsertWithoutNameReferenceInstruction = {
    instruction_type: "insert_without_name_reference"
    huffman_encoded_name: bool
    ? name_length: uint32
    ? name: text
    huffman_encoded_value: bool
    ? value_length: uint32
    ? value: text
}
Figure 32: InsertWithoutNameReferenceInstruction definition

B.2.4. DuplicateInstruction

DuplicateInstruction = {
    instruction_type: "duplicate"
    index: uint32
}
Figure 33: DuplicateInstruction definition

B.2.5. SectionAcknowledgementInstruction

SectionAcknowledgementInstruction = {
    instruction_type: "section_acknowledgement"
    stream_id: uint64
}
Figure 34: SectionAcknowledgementInstruction definition

B.2.6. StreamCancellationInstruction

StreamCancellationInstruction = {
    instruction_type: "stream_cancellation"
    stream_id: uint64
}
Figure 35: StreamCancellationInstruction definition

B.2.7. InsertCountIncrementInstruction

InsertCountIncrementInstruction = {
    instruction_type: "insert_count_increment"
    increment: uint32
}
Figure 36: InsertCountIncrementInstruction definition

B.3. QPACK Header compression

QPACKHeaderBlockRepresentation =  IndexedHeaderField /
                                  LiteralHeaderFieldWithName /
                                  LiteralHeaderFieldWithoutName
Figure 37: QPACKHeaderBlockRepresentation definition

B.3.1. IndexedHeaderField

Note: also used for "indexed header field with post-base index"

IndexedHeaderField = {
    header_field_type: "indexed_header"

    ; MUST be "dynamic" if is_post_base is true
    table_type: QPACKTableType
    index: uint32

    ; to represent the "indexed header field with post-base index"
    ; header field type
    is_post_base: bool .default false
}
Figure 38: IndexedHeaderField definition

B.3.2. LiteralHeaderFieldWithName

Note: also used for "Literal header field with post-base name reference"

LiteralHeaderFieldWithName = {
    header_field_type: "literal_with_name"

    ; the 3rd "N" bit
    preserve_literal: bool

    ; MUST be "dynamic" if is_post_base is true
    table_type: QPACKTableType
    name_index: uint32
    huffman_encoded_value: bool
    ? value_length: uint32
    ? value: text

    ; to represent the "indexed header field with post-base index"
    ; header field type
    is_post_base: bool .default false
}
Figure 39: LiteralHeaderFieldWithName definition

B.3.3. LiteralHeaderFieldWithoutName

LiteralHeaderFieldWithoutName = {
    header_field_type: "literal_without_name"

    ; the 3rd "N" bit
    preserve_literal: bool
    huffman_encoded_name: bool
    ? name_length: uint32
    ? name: text

    huffman_encoded_value: bool
    ? value_length: uint32
    ? value: text
}
Figure 40: LiteralHeaderFieldWithoutName definition

B.3.4. QPACKHeaderBlockPrefix

QPACKHeaderBlockPrefix = {
    required_insert_count: uint32
    sign_bit: bool
    delta_base: uint32
}
Figure 41: QPACKHeaderBlockPrefix definition

B.3.5. QPACKTableType

QPACKTableType = "static" / "dynamic"
Figure 42: QPACKTableType definition

Appendix C. Change Log

C.1. Since draft-ietf-quic-qlog-h3-events-01:

  • No changes - new draft to prevent expiration

C.2. Since draft-ietf-quic-qlog-h3-events-00:

  • Change the data definition language from TypeScript to CDDL (#143)

C.3. Since draft-marx-qlog-event-definitions-quic-h3-02:

  • These changes were done in preparation of the adoption of the drafts by the QUIC working group (#137)
  • Split QUIC and HTTP/3 events into two separate documents
  • Moved RawInfo, Importance, Generic events and Simulation events to the main schema document.

C.4. Since draft-marx-qlog-event-definitions-quic-h3-01:

Major changes:

  • Moved data_moved from http to transport. Also made the "from" and "to" fields flexible strings instead of an enum (#111,#65)
  • Moved packet_type fields to PacketHeader. Moved packet_size field out of PacketHeader to RawInfo:length (#40)
  • Made events that need to log packet_type and packet_number use a header field instead of logging these fields individually
  • Added support for logging retry, stateless reset and initial tokens (#94,#86,#117)
  • Moved separate general event categories into a single category "generic" (#47)
  • Added "transport:connection_closed" event (#43,#85,#78,#49)
  • Added version_information and alpn_information events (#85,#75,#28)
  • Added parameters_restored events to help clarify 0-RTT behaviour (#88)

Smaller changes:

  • Merged loss_timer events into one loss_timer_updated event
  • Field data types are now strongly defined (#10,#39,#36,#115)
  • Renamed qpack instruction_received and instruction_sent to instruction_created and instruction_parsed (#114)
  • Updated qpack:dynamic_table_updated.update_type. It now has the value "inserted" instead of "added" (#113)
  • Updated qpack:dynamic_table_updated. It now has an "owner" field to differentiate encoder vs decoder state (#112)
  • Removed push_allowed from http:parameters_set (#110)
  • Removed explicit trigger field indications from events, since this was moved to be a generic property of the "data" field (#80)
  • Updated transport:connection_id_updated to be more in line with other similar events. Also dropped importance from Core to Base (#45)
  • Added length property to PaddingFrame (#34)
  • Added packet_number field to transport:frames_processed (#74)
  • Added a way to generically log packet header flags (first 8 bits) to PacketHeader
  • Added additional guidance on which events to log in which situations (#53)
  • Added "simulation:scenario" event to help indicate simulation details
  • Added "packets_acked" event (#107)
  • Added "datagram_ids" to the datagram_X and packet_X events to allow tracking of coalesced QUIC packets (#91)
  • Extended connection_state_updated with more fine-grained states (#49)

C.5. Since draft-marx-qlog-event-definitions-quic-h3-00:

  • Event and category names are now all lowercase
  • Added many new events and their definitions
  • "type" fields have been made more specific (especially important for PacketType fields, which are now called packet_type instead of type)
  • Events are given an importance indicator (issue #22)
  • Event names are more consistent and use past tense (issue #21)
  • Triggers have been redefined as properties of the "data" field and updated for most events (issue #23)

Appendix D. Design Variations

TBD

Appendix E. Acknowledgements

Much of the initial work by Robin Marx was done at Hasselt University.

Thanks to Marten Seemann, Jana Iyengar, Brian Trammell, Dmitri Tikhonov, Stephen Petrides, Jari Arkko, Marcus Ihlar, Victor Vasiliev, Mirja Kuehlewind, Jeremy Laine, Kazu Yamamoto, Christian Huitema, and Lucas Pardue for their feedback and suggestions.

Authors' Addresses

Robin Marx
KU Leuven
Luca Niccolini (editor)
Facebook
Marten Seemann (editor)
Protocol Labs