QUIC R. Marx
Internet-Draft KU Leuven
Intended status: Standards Track L. Niccolini, Ed.
Expires: November 18, 2021 Facebook
M. Seemann, Ed.
Protocol Labs
May 17, 2021
HTTP/3 and QPACK event definitions for qlog
draft-marx-quic-qlog-h3-events-00
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 November 18, 2021.
Copyright Notice
Copyright (c) 2021 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 Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Usage with QUIC . . . . . . . . . . . . . . . . . . . . . 4
2.2. Links to the main schema . . . . . . . . . . . . . . . . 4
2.2.1. Raw packet and frame information . . . . . . . . . . 4
3. HTTP/3 and QPACK event definitions . . . . . . . . . . . . . 5
3.1. http . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.1. parameters_set . . . . . . . . . . . . . . . . . . . 5
3.1.2. parameters_restored . . . . . . . . . . . . . . . . . 6
3.1.3. stream_type_set . . . . . . . . . . . . . . . . . . . 6
3.1.4. frame_created . . . . . . . . . . . . . . . . . . . . 7
3.1.5. frame_parsed . . . . . . . . . . . . . . . . . . . . 8
3.1.6. push_resolved . . . . . . . . . . . . . . . . . . . . 8
3.2. qpack . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2.1. state_updated . . . . . . . . . . . . . . . . . . . . 9
3.2.2. stream_state_updated . . . . . . . . . . . . . . . . 9
3.2.3. dynamic_table_updated . . . . . . . . . . . . . . . . 10
3.2.4. headers_encoded . . . . . . . . . . . . . . . . . . . 10
3.2.5. headers_decoded . . . . . . . . . . . . . . . . . . . 11
3.2.6. instruction_created . . . . . . . . . . . . . . . . . 11
3.2.7. instruction_parsed . . . . . . . . . . . . . . . . . 12
4. Security Considerations . . . . . . . . . . . . . . . . . . . 12
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
6.1. Normative References . . . . . . . . . . . . . . . . . . 12
6.2. Informative References . . . . . . . . . . . . . . . . . 13
6.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Appendix A. HTTP/3 data field definitions . . . . . . . . . . . 13
A.1. HTTP/3 Frames . . . . . . . . . . . . . . . . . . . . . . 13
A.1.1. DataFrame . . . . . . . . . . . . . . . . . . . . . . 13
A.1.2. HeadersFrame . . . . . . . . . . . . . . . . . . . . 13
A.1.3. CancelPushFrame . . . . . . . . . . . . . . . . . . . 14
A.1.4. SettingsFrame . . . . . . . . . . . . . . . . . . . . 14
A.1.5. PushPromiseFrame . . . . . . . . . . . . . . . . . . 14
A.1.6. GoAwayFrame . . . . . . . . . . . . . . . . . . . . . 14
A.1.7. MaxPushIDFrame . . . . . . . . . . . . . . . . . . . 15
A.1.8. DuplicatePushFrame . . . . . . . . . . . . . . . . . 15
A.1.9. ReservedFrame . . . . . . . . . . . . . . . . . . . . 15
A.1.10. UnknownFrame . . . . . . . . . . . . . . . . . . . . 15
A.2. ApplicationError . . . . . . . . . . . . . . . . . . . . 15
Appendix B. QPACK DATA type definitions . . . . . . . . . . . . 16
B.1. QPACK Instructions . . . . . . . . . . . . . . . . . . . 16
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B.1.1. SetDynamicTableCapacityInstruction . . . . . . . . . 16
B.1.2. InsertWithNameReferenceInstruction . . . . . . . . . 16
B.1.3. InsertWithoutNameReferenceInstruction . . . . . . . . 16
B.1.4. DuplicateInstruction . . . . . . . . . . . . . . . . 17
B.1.5. HeaderAcknowledgementInstruction . . . . . . . . . . 17
B.1.6. StreamCancellationInstruction . . . . . . . . . . . . 17
B.1.7. InsertCountIncrementInstruction . . . . . . . . . . . 17
B.2. QPACK Header compression . . . . . . . . . . . . . . . . 17
B.2.1. IndexedHeaderField . . . . . . . . . . . . . . . . . 17
B.2.2. LiteralHeaderFieldWithName . . . . . . . . . . . . . 18
B.2.3. LiteralHeaderFieldWithoutName . . . . . . . . . . . . 18
B.2.4. QPackHeaderBlockPrefix . . . . . . . . . . . . . . . 18
Appendix C. Change Log . . . . . . . . . . . . . . . . . . . . . 18
C.1. Since draft-marx-qlog-event-definitions-quic-h3-02: . . . 19
C.2. Since draft-marx-qlog-event-definitions-quic-h3-01: . . . 19
C.3. Since draft-marx-qlog-event-definitions-quic-h3-00: . . . 20
Appendix D. Design Variations . . . . . . . . . . . . . . . . . 21
Appendix E. Acknowledgements . . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
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/quiclog/
internet-drafts [1]. 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/ [2].
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 examples and data definitions in ths document are expressed in a
custom data definition language, inspired by JSON and TypeScript, and
described in [QLOG-MAIN].
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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).
2.2. Links to the main schema
This document re-uses all the fields defined in the main qlog schema
(e.g., name, category, type, data, group_id, protocol_type, the time-
related fields, importance, RawInfo, etc.).
One entry in the "protocol_type" qlog array field MUST be "HTTP3" if
events from this document are included in a qlog trace.
2.2.1. Raw packet and frame information
This document re-uses the definition of the RawInfo data class from
[QLOG-MAIN].
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Note: As HTTP/3 does not use trailers in frames, each HTTP/3 frame
header_length can be calculated as header_length = RawInfo:length
- RawInfo:payload_length
Note: In some cases, the length fields are also explicitly reflected
inside of frame headers. For example, all HTTP/3 frames include
their explicit payload lengths in the frame header. In these
cases, those fields are intentionally preserved in the event
definitions. Even though this can lead to duplicate data when the
full RawInfo is logged, it allows a more direct mapping of the
HTTP/3 specifications to qlog, making it easier for users to
interpret. In this case, both fields MUST have the same value.
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.
Data:
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{
owner?:"local" | "remote",
max_header_list_size?:uint64, // from SETTINGS_MAX_HEADER_LIST_SIZE
max_table_capacity?:uint64, // from SETTINGS_QPACK_MAX_TABLE_CAPACITY
blocked_streams_count?:uint64, // from SETTINGS_QPACK_BLOCKED_STREAMS
// qlog-defined
waits_for_settings?:boolean // indicates whether this implementation waits for a SETTINGS frame before processing requests
}
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.
Data:
{
max_header_list_size?:uint64,
max_table_capacity?:uint64,
blocked_streams_count?:uint64
}
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.
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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.
Data:
{
stream_id:uint64,
owner?:"local"|"remote"
old?:StreamType,
new:StreamType,
associated_push_id?:uint64 // only when new == "push"
}
enum StreamType {
data, // bidirectional request-response streams
control,
push,
reserved,
qpack_encode,
qpack_decode
}
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].
Data:
{
stream_id:uint64,
length?:uint64, // payload byte length of the frame
frame:HTTP3Frame, // see appendix for the definitions,
raw?:RawInfo
}
Note: in HTTP/3, DATA frames can have arbitrarily large lengths to
reduce frame header overhead. As such, DATA frames can span many
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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].
Data:
{
stream_id:uint64,
length?:uint64, // payload byte length of the frame
frame:HTTP3Frame, // see appendix for the definitions,
raw?:RawInfo
}
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.
{
push_id?:uint64,
stream_id?:uint64, // in case this is logged from a place that does not have access to the push_id
decision:"claimed"|"abandoned"
}
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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.
Data:
{
owner:"local" | "remote",
dynamic_table_capacity?:uint64,
dynamic_table_size?:uint64, // effective current size, sum of all the entries
known_received_count?:uint64,
current_insert_count?:uint64
}
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.
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Note: This event is of "Core" importance, as it might have a large
impact on HTTP/3's observed performance.
Data:
{
stream_id:uint64,
state:"blocked"|"unblocked" // streams are assumed to start "unblocked" until they become "blocked"
}
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.
Data:
{
owner:"local" | "remote", // local = the encoder's dynamic table. remote = the decoder's dynamic table
update_type:"inserted"|"evicted",
entries:Array<DynamicTableEntry>
}
class DynamicTableEntry {
index:uint64;
name?:string | bytes;
value?:string | bytes;
}
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.
Data:
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{
stream_id?:uint64,
headers?:Array<HTTPHeader>,
block_prefix:QPackHeaderBlockPrefix,
header_block:Array<QPackHeaderBlockRepresentation>,
length?:uint32,
raw?:bytes
}
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.
Data:
{
stream_id?:uint64,
headers?:Array<HTTPHeader>,
block_prefix:QPackHeaderBlockPrefix,
header_block:Array<QPackHeaderBlockRepresentation>,
length?:uint32,
raw?:bytes
}
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.
Data:
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{
instruction:QPackInstruction // see appendix for the definitions,
length?:uint32,
raw?:bytes
}
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.
Data:
{
instruction:QPackInstruction // see appendix for the definitions,
length?:uint32,
raw?:bytes
}
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
[QLOG-MAIN]
Marx, R., Ed., Niccolini, L., Ed., and M. Seemann, Ed.,
"Main logging schema for qlog", draft-marx-qlog-main-
schema-04 (work in progress).
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[QLOG-QUIC]
Marx, R., Ed., Niccolini, L., Ed., and M. Seemann, Ed.,
"QUIC event definitions for qlog", draft-marx-quic-qlog-
quic-events-00 (work in progress).
[QUIC-HTTP]
Bishop, M., Ed., "Hypertext Transfer Protocol Version 3
(HTTP/3)", draft-ietf-quic-http-latest (work in progress).
[QUIC-QPACK]
Krasic, C., Bishop, M., and A. Frindell, Ed., "QPACK:
Header Compression for HTTP over QUIC", draft-ietf-quic-
qpack-latest (work in progress).
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, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
6.3. URIs
[1] https://github.com/quiclog/internet-drafts
[2] https://github.com/quiclog/qlog/
Appendix A. HTTP/3 data field definitions
A.1. HTTP/3 Frames
type HTTP3Frame = DataFrame | HeadersFrame | PriorityFrame | CancelPushFrame | SettingsFrame | PushPromiseFrame | GoAwayFrame | MaxPushIDFrame | DuplicatePushFrame | ReservedFrame | UnknownFrame;
A.1.1. DataFrame
class DataFrame{
frame_type:string = "data";
raw?:bytes;
}
A.1.2. HeadersFrame
This represents an _uncompressed_, plaintext HTTP Headers frame
(e.g., no QPACK compression is applied).
For example:
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headers: [{"name":":path","value":"/"},{"name":":method","value":"GET"},{"name":":authority","value":"127.0.0.1:4433"},{"name":":scheme","value":"https"}]
class HeadersFrame{
frame_type:string = "header";
headers:Array<HTTPHeader>;
}
class HTTPHeader {
name:string;
value:string;
}
A.1.3. CancelPushFrame
class CancelPushFrame{
frame_type:string = "cancel_push";
push_id:uint64;
}
A.1.4. SettingsFrame
class SettingsFrame{
frame_type:string = "settings";
settings:Array<Setting>;
}
class Setting{
name:string;
value:string;
}
A.1.5. PushPromiseFrame
class PushPromiseFrame{
frame_type:string = "push_promise";
push_id:uint64;
headers:Array<HTTPHeader>;
}
A.1.6. GoAwayFrame
class GoAwayFrame{
frame_type:string = "goaway";
stream_id:uint64;
}
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A.1.7. MaxPushIDFrame
class MaxPushIDFrame{
frame_type:string = "max_push_id";
push_id:uint64;
}
A.1.8. DuplicatePushFrame
class DuplicatePushFrame{
frame_type:string = "duplicate_push";
push_id:uint64;
}
A.1.9. ReservedFrame
class ReservedFrame{
frame_type:string = "reserved";
}
A.1.10. UnknownFrame
HTTP/3 re-uses QUIC's UnknownFrame definition, since their values and
usage overlaps. See [QLOG-QUIC].
A.2. ApplicationError
enum ApplicationError{
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
}
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Appendix B. QPACK DATA type definitions
B.1. 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.
type QPackInstruction = SetDynamicTableCapacityInstruction | InsertWithNameReferenceInstruction | InsertWithoutNameReferenceInstruction | DuplicateInstruction | HeaderAcknowledgementInstruction | StreamCancellationInstruction | InsertCountIncrementInstruction;
B.1.1. SetDynamicTableCapacityInstruction
class SetDynamicTableCapacityInstruction {
instruction_type:string = "set_dynamic_table_capacity";
capacity:uint32;
}
B.1.2. InsertWithNameReferenceInstruction
class InsertWithNameReferenceInstruction {
instruction_type:string = "insert_with_name_reference";
table_type:"static"|"dynamic";
name_index:uint32;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
B.1.3. InsertWithoutNameReferenceInstruction
class InsertWithoutNameReferenceInstruction {
instruction_type:string = "insert_without_name_reference";
huffman_encoded_name:boolean;
name_length?:uint32;
name?:string;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
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B.1.4. DuplicateInstruction
class DuplicateInstruction {
instruction_type:string = "duplicate";
index:uint32;
}
B.1.5. HeaderAcknowledgementInstruction
class HeaderAcknowledgementInstruction {
instruction_type:string = "header_acknowledgement";
stream_id:uint64;
}
B.1.6. StreamCancellationInstruction
class StreamCancellationInstruction {
instruction_type:string = "stream_cancellation";
stream_id:uint64;
}
B.1.7. InsertCountIncrementInstruction
class InsertCountIncrementInstruction {
instruction_type:string = "insert_count_increment";
increment:uint32;
}
B.2. QPACK Header compression
type QPackHeaderBlockRepresentation = IndexedHeaderField | LiteralHeaderFieldWithName | LiteralHeaderFieldWithoutName;
B.2.1. IndexedHeaderField
Note: also used for "indexed header field with post-base index"
class IndexedHeaderField {
header_field_type:string = "indexed_header";
table_type:"static"|"dynamic"; // MUST be "dynamic" if is_post_base is true
index:uint32;
is_post_base:boolean = false; // to represent the "indexed header field with post-base index" header field type
}
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B.2.2. LiteralHeaderFieldWithName
Note: also used for "Literal header field with post-base name
reference"
class LiteralHeaderFieldWithName {
header_field_type:string = "literal_with_name";
preserve_literal:boolean; // the 3rd "N" bit
table_type:"static"|"dynamic"; // MUST be "dynamic" if is_post_base is true
name_index:uint32;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
is_post_base:boolean = false; // to represent the "Literal header field with post-base name reference" header field type
}
B.2.3. LiteralHeaderFieldWithoutName
class LiteralHeaderFieldWithoutName {
header_field_type:string = "literal_without_name";
preserve_literal:boolean; // the 3rd "N" bit
huffman_encoded_name:boolean;
name_length?:uint32;
name?:string;
huffman_encoded_value:boolean;
value_length?:uint32;
value?:string;
}
B.2.4. QPackHeaderBlockPrefix
class QPackHeaderBlockPrefix {
required_insert_count:uint32;
sign_bit:boolean;
delta_base:uint32;
}
Appendix C. Change Log
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C.1. Since draft-marx-qlog-event-definitions-quic-h3-02:
o These changes were done in preparation of the adoption of the
drafts by the QUIC working group (#137)
o Split QUIC and HTTP/3 events into two separate documents
o Moved RawInfo, Importance, Generic events and Simulation events to
the main schema document.
C.2. Since draft-marx-qlog-event-definitions-quic-h3-01:
Major changes:
o Moved data_moved from http to transport. Also made the "from" and
"to" fields flexible strings instead of an enum (#111,#65)
o Moved packet_type fields to PacketHeader. Moved packet_size field
out of PacketHeader to RawInfo:length (#40)
o Made events that need to log packet_type and packet_number use a
header field instead of logging these fields individually
o Added support for logging retry, stateless reset and initial
tokens (#94,#86,#117)
o Moved separate general event categories into a single category
"generic" (#47)
o Added "transport:connection_closed" event (#43,#85,#78,#49)
o Added version_information and alpn_information events
(#85,#75,#28)
o Added parameters_restored events to help clarify 0-RTT behaviour
(#88)
Smaller changes:
o Merged loss_timer events into one loss_timer_updated event
o Field data types are now strongly defined (#10,#39,#36,#115)
o Renamed qpack instruction_received and instruction_sent to
instruction_created and instruction_parsed (#114)
o Updated qpack:dynamic_table_updated.update_type. It now has the
value "inserted" instead of "added" (#113)
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o Updated qpack:dynamic_table_updated. It now has an "owner" field
to differentiate encoder vs decoder state (#112)
o Removed push_allowed from http:parameters_set (#110)
o Removed explicit trigger field indications from events, since this
was moved to be a generic property of the "data" field (#80)
o Updated transport:connection_id_updated to be more in line with
other similar events. Also dropped importance from Core to Base
(#45)
o Added length property to PaddingFrame (#34)
o Added packet_number field to transport:frames_processed (#74)
o Added a way to generically log packet header flags (first 8 bits)
to PacketHeader
o Added additional guidance on which events to log in which
situations (#53)
o Added "simulation:scenario" event to help indicate simulation
details
o Added "packets_acked" event (#107)
o Added "datagram_ids" to the datagram_X and packet_X events to
allow tracking of coalesced QUIC packets (#91)
o Extended connection_state_updated with more fine-grained states
(#49)
C.3. Since draft-marx-qlog-event-definitions-quic-h3-00:
o Event and category names are now all lowercase
o Added many new events and their definitions
o "type" fields have been made more specific (especially important
for PacketType fields, which are now called packet_type instead of
type)
o Events are given an importance indicator (issue #22)
o Event names are more consistent and use past tense (issue #21)
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o 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
Email: robin.marx@kuleuven.be
Luca Niccolini (editor)
Facebook
Email: lniccolini@fb.com
Marten Seemann (editor)
Protocol Labs
Email: marten@protocol.ai
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