QUIC A. Ferrieux, Ed.
Internet-Draft Orange Labs
Intended status: Standards Track I. Lubashev, Ed.
Expires: 1 September 2025 Akamai Technologies
G. Fioccola, Ed.
Huawei Technologies
M. Ihlar, Ed.
Ericsson
F. Bulgarella
Telecom Italia - TIM
M. Cociglio
I. Hamchaoui
Orange Labs
M. Nilo
Telecom Italia - TIM
28 February 2025
Application of Explicit Measurement Techniques for QUIC Troubleshooting
draft-mdt-quic-explicit-measurements-02
Abstract
This document defines a protocol that can be used by QUIC endpoints
to signal packet loss in a way that can be used by network devices to
measure and locate the source of the loss.
Discussion of this work is encouraged to happen on the QUIC IETF
mailing list quic@ietf.org (mailto:quic@ietf.org) or on the GitHub
repository which contains the draft: https://github.com/igorlord/
draft-mdt-quic-explicit-measurements (https://github.com/igorlord/
draft-mdt-quic-explicit-measurements).
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."
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This Internet-Draft will expire on 1 September 2025.
Copyright Notice
Copyright (c) 2025 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
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
2. On-Path RTT Observation . . . . . . . . . . . . . . . . . . . 4
3. On-Path Loss Observation . . . . . . . . . . . . . . . . . . 4
3.1. On-Path Loss Signaling Protocol . . . . . . . . . . . . . 4
3.2. Recommended Use of the Signals . . . . . . . . . . . . . 5
4. Loss Bits . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Setting the sQuare Signal Bit on Outgoing Packets . . . . 5
4.1.1. Q Run Length Selection . . . . . . . . . . . . . . . 5
4.2. Setting the Loss Event Bit on Outgoing Packets . . . . . 6
5. Using Loss Bits for Passive Loss Measurement . . . . . . . . 6
5.1. End-To-End Loss . . . . . . . . . . . . . . . . . . . . . 7
5.2. Upstream Loss . . . . . . . . . . . . . . . . . . . . . . 7
5.3. Correlating End-to-End and Upstream Loss . . . . . . . . 7
5.4. Downstream Loss . . . . . . . . . . . . . . . . . . . . . 8
5.5. Observer Loss . . . . . . . . . . . . . . . . . . . . . . 8
6. Implementation . . . . . . . . . . . . . . . . . . . . . . . 8
6.1. EFMP Packet . . . . . . . . . . . . . . . . . . . . . . . 8
6.2. Transport Parameter . . . . . . . . . . . . . . . . . . . 10
6.3. EFMP Packet Processing . . . . . . . . . . . . . . . . . 10
7. Ossification Considerations . . . . . . . . . . . . . . . . . 10
8. Security Considerations . . . . . . . . . . . . . . . . . . . 11
8.1. Optimistic ACK Attack . . . . . . . . . . . . . . . . . . 11
9. Privacy Considerations . . . . . . . . . . . . . . . . . . . 11
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
11. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 12
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
13.1. Normative References . . . . . . . . . . . . . . . . . . 12
13.2. Informative References . . . . . . . . . . . . . . . . . 13
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Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
Packet loss is a hard and pervasive problem of day-to-day network
operation. Proactively detecting, measuring, and locating it is
crucial to maintaining high QoS and timely resolution of crippling
end-to-end throughput issues. To this effect, in a TCP-dominated
world, network operators have been heavily relying on information
present in the clear in TCP headers: sequence and acknowledgment
numbers, and SACKs when enabled. These allow for quantitative
estimation of packet loss by passive on-path observation.
With QUIC, the equivalent transport headers are encrypted, and
passive packet loss observation is not possible, as described in
[RFC9065].
Measuring TCP loss between similar endpoints cannot be relied upon to
evaluate QUIC loss. QUIC could be routed by the network differently
and the fraction of Internet traffic delivered using QUIC is
increasing every year. It is imperative to measure packet loss
experienced by QUIC users directly.
The Alternate-Marking method [AltMark] defines a consolidated method
to perform packet loss, delay, and jitter measurements on live
traffic. However, as noted in [EXPLICIT-MEASUREMENTS], applying
[AltMark] to end-to-end transport-layer connections is not easy
because packet identification and marking by network nodes is
prevented when QUIC encrypted transport-layer header is being used.
This document defines the Explicit Flow Measurement Protocol (EFMP)
which is used by QUIC endpoints to enable packet loss measurements
using Explicit Host-to-Network Flow Measurement Techniques defined in
[EXPLICIT-MEASUREMENTS].
Measurement bits are sent in dedicated EFMP packets that are
coalesced with other QUIC packets in UDP datagrams.
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].
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2. On-Path RTT Observation
[QUIC-TRANSPORT] already introduces an explicit per-flow transport-
layer signal for hybrid measurement of RTT. This signal consists of
a Spin bit that toggles once per RTT.
3. On-Path Loss Observation
There are three sources of loss that network operators need to
observe to guarantee high QoS:
* _upstream loss_ - loss between the sender and the observation
point (Section 5.2)
* _downstream loss_ - loss between the observation point and the
destination (Section 5.4)
* _observer loss_ - loss by the observer itself that does not cause
downstream loss (Section 5.5)
The upstream and downstream loss together constitute _end-to-end
loss_ (Section 5.1).
3.1. On-Path Loss Signaling Protocol
[EXPLICIT-MEASUREMENTS] introduces several techniques for using
explicit loss bits in the clear portion of transport protocol headers
to signal packet loss to on-path network devices. The explicit loss
bits used in this document are the "sQuare signal" bit (Q) and the
"Loss event" bit (L) (see Section 4.1 and Section 4.2). This
approach follows the recommendations of [RFC8558] that recommends
explicit path signals.
This document defines the Explicit Flow Measurement Protocol (EFMP)
that takes inspiration from [TRAIN] that uses QUIC Long Header
packets that are prepended to QUIC v1 or v2 packets as carriers of
path signals.
While the exploitation of only Q can help in measuring the _upstream
loss_ and only L can help in measuring the _end-to-end loss_, both
are required to detect and measure the other types of losses
(_downstream loss_ and _observer loss_).
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3.2. Recommended Use of the Signals
The loss signal is not designed for use in automated control of the
network in environments where loss bits are set by untrusted hosts.
Instead, the signal is to be used for troubleshooting individual
flows and for monitoring the network by aggregating information from
multiple flows and raising operator alarms if aggregate statistics
indicate a potential problem.
4. Loss Bits
The draft introduces two bits that are to be present in EFMP packets.
* Q: The "sQuare signal" bit is toggled every N outgoing packets, as
explained below in Section 4.1.
* L: The "Loss event" bit is set to 0 or 1 according to the
Unreported Loss counter, as explained below in Section 4.2.
Each endpoint maintains appropriate counters independently and
separately for each connection 4-tuple and Destination Connection ID.
Whenever this specification refers to connections, it is referring to
packets sharing the same 4-tuple and Destination Connection ID. A
"QUIC connection", however, refers to connections in the traditional
QUIC sense.
4.1. Setting the sQuare Signal Bit on Outgoing Packets
The sQuare bit (Q bit) takes its name from the square wave generated
by its signal. This method is based on the Alternate-Marking method
[AltMark]. The sQuare Value is initialized to the Initial Q Value (0
or 1) and is reflected in the Q bit of every outgoing packet. The
sQuare value is inverted after sending every N packets (a Q run).
Hence, Q Period is 2*N. The Q bit represents "packet color" as
defined by [RFC8321].
Observation points can estimate upstream losses by counting the
number of packets during one period of the square signal, as
described in Section 5.
4.1.1. Q Run Length Selection
The sender is expected to choose N (Q run length) based on the
expected amount of loss and reordering on the path. The choice of N
strikes a compromise -- the observation could become too unreliable
in case of packet reordering and/or severe loss if N is too small,
while short connections may not yield a useful upstream loss
measurement if N is too large (see Section 5.2).
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The value of N MUST be at least 64 and be a power of 2. This
requirement allows an Observer to infer the Q run length by observing
one period of the square signal. It also allows the Observer to
identify flows that set the loss bits to arbitrary values (see
Section 7).
If the sender does not have sufficient information to make an
informed decision about Q run length, the sender SHOULD use N=64,
since this value has been extensively tested in large-scale field
tests and yielded good results. Alternatively, the sender MAY also
choose a random N for each connection, increasing the chances of
using a Q run length that gives the best signal for some connections.
The sender MUST keep the value of N constant for a given connection.
The sender can change the value of N during a QUIC connection by
switching to a new Destination Connection ID, if one is available.
4.2. Setting the Loss Event Bit on Outgoing Packets
The Loss Event bit uses the Unreported Loss counter maintained by the
QUIC protocol. The Unreported Loss counter is initialized to 0, and
the L bit of every outgoing packet indicates whether the Unreported
Loss counter is positive (L=1 if the counter is positive, and L=0
otherwise). The value of the Unreported Loss counter is decremented
every time a packet with L=1 is sent.
The value of the Unreported Loss counter is incremented for every
packet that the protocol declares lost, using QUIC's existing loss
detection machinery. If the implementation is able to rescind the
loss determination later, a positive Unreported Loss counter MAY be
decremented due to the rescission, but it SHOULD NOT become negative.
This loss signaling is similar to loss signaling in [RFC7713], except
the Loss Event bit is reporting the exact number of lost packets,
whereas the Echo Loss bit in [RFC7713] is reporting an approximate
number of lost bytes.
Observation points can estimate the end-to-end loss, as determined by
the upstream endpoint, by counting packets in this direction with the
L bit equal to 1, as described in Section 5.
5. Using Loss Bits for Passive Loss Measurement
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5.1. End-To-End Loss
The Loss Event bit allows an observer to calculate the end-to-end
loss rate by counting packets with the L bit value of 0 and 1 for a
given connection. The end-to-end loss rate is the fraction of
packets with L=1.
The assumption here is that upstream loss affects packets with L=0
and L=1 equally. If some loss is caused by tail-drop in a network
device, this may be a simplification. If the sender congestion
controller reduces the packet send rate after loss, there may be a
sufficient delay before sending packets with L=1 that they have a
greater chance of arriving at the observer.
5.2. Upstream Loss
Blocks of N (Q run length) consecutive packets are sent with the same
value of the Q bit, followed by another block of N packets with an
inverted value of the Q bit. Hence, knowing the value of N, an on-
path observer can estimate the amount of loss after observing at
least N packets. The upstream loss rate (u) is one minus the average
number of packets in a block of packets with the same Q value (p)
divided by N (u=1-avg(p)/N).
The observer needs to be able to tolerate packet reordering that can
blur the edges of the square signal.
The observer needs to differentiate packets as belonging to different
connections, since they use independent counters.
5.3. Correlating End-to-End and Upstream Loss
Upstream loss is calculated by observing packets that did not suffer
the upstream loss. End-to-end loss, however, is calculated by
observing subsequent packets after the sender's protocol detected the
loss. Hence, end-to-end loss is generally observed with a delay of
between 1 RTT (loss declared due to multiple duplicate
acknowledgments) and 1 RTO (loss declared due to a timeout) relative
to the upstream loss.
The connection RTT can sometimes be estimated by timing protocol
handshake messages. This RTT estimate can be greatly improved by
observing a dedicated protocol mechanism for conveying RTT
information, such as the latency Spin bit of [QUIC-TRANSPORT].
Whenever the observer needs to perform a computation that uses both
upstream and end-to-end loss rate measurements, it SHOULD use
upstream loss rate leading the end-to-end loss rate by approximately
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1 RTT. If the observer is unable to estimate RTT of the connection,
it should accumulate loss measurements over time periods of at least
4 times the typical RTT for the observed connections.
If the calculated upstream loss rate exceeds the end-to-end loss rate
calculated in Section 5.1, then either the Q run length is too short
for the amount of packet reordering or there is observer loss,
described in Section 5.5. If this happens, the observer SHOULD
adjust the calculated upstream loss rate to match end-to-end loss
rate.
5.4. Downstream Loss
Because downstream loss affects only those packets that did not
suffer upstream loss, the end-to-end loss rate (e) relates to the
upstream loss rate (u) and downstream loss rate (d) as
(1-u)(1-d)=1-e. Hence, d=(e-u)/(1-u).
5.5. Observer Loss
A typical deployment of a passive observation system includes a
network tap device that mirrors network packets of interest to a
device that performs analysis and measurement on the mirrored
packets. The observer loss is the loss that occurs on the mirror
path.
Observer loss affects upstream loss rate measurement, since it causes
the observer to account for fewer packets in a block of identical Q
bit values (see Section 5.2). The end-to-end loss rate measurement,
however, is unaffected by the observer loss, since it is a
measurement of the fraction of packets with the set L bit value, and
the observer loss would affect all packets equally (see Section 5.1).
The need to adjust the upstream loss rate down to match end-to-end
loss rate as described in Section 5.3 is a strong indication of the
observer loss, whose magnitude is between the amount of such
adjustment and the entirety of the upstream loss measured in
Section 5.2. Alternatively, a high apparent upstream loss rate could
be an indication of significant reordering, possibly due to packets
belonging to a single connection being multiplexed over several
upstream paths with different latency characteristics.
6. Implementation
6.1. EFMP Packet
An EFMP packet is a QUIC long header packet that follows the QUIC
invariants; see Section 5.1 of [INVARIANTS].
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Figure 1 shows the format of the EFMP packet using the conventions
from Section 4 of [INVARIANTS].
EFMP Packet {
Header Form (1) = 1,
Reserved (1),
Q Bit (1),
L Bit (1),
Spin Bit (1),
Reserved (3),
Version (32) = 0xTBD,
Destination Connection ID Length (8),
Destination Connection ID (0..2040),
Source Connection ID Length (8),
Source Connection ID (0..2040),
}
Figure 1: EFMP Packet Format
The most significant bit (0x80) of the packet indicates that this is
a QUIC long header packet. The next bit (0x40) is reserved and can
be set according to [QUIC-BIT].
The six least significant bits of the first octet of an EFMP packet
forms the EFMP payload:
sQuare Signal Bit (Q): The first bit of the EFMP payload (0x20) is
is the sQuare signal bit, set as described in Section 4.1.
Loss Event Bit (L): The second bit (0x10) is the Loss event bit, set
as described in Section 4.2.
Latency Spin Bit (S): The third bit (0x8) is the latency spin bit.
This bit is set to the value of the spin bit in the QUIC Short
Header packet that follows directly after the EFMP packet in the
same UDP datagram.
The three least significant bits (0x7) are reserved for future use.
An EFMP packet includes a Destination Connection ID field that is set
to the same value as other packets in the same datagram; see
Section 12.2 of [QUIC-TRANSPORT].
The Source Connection ID field is set to match the Source Connection
ID field of any packet that follows. If the next packet in the
datagram has a short header (Section 5.2 of [INVARIANTS]), the Source
Connection ID field is empty.
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EFMP packets are always coalesced with other QUIC packets and SHOULD
be included as the first packet in a UDP datagram.
6.2. Transport Parameter
A QUIC endpoint indicates that it is willing to receive EFMP packets
by including the transport parameter:
efmp_supported (0xTBD): efmp_supported transport parameter is an
integer value, encoded as a variable-length integer, that can be
set to 0 or 1, indicating the level of EFMP support. The value of
0 indicates that the endpoint is able to receive EFMP packets but
will not be sending any, while the value of 1 indicates that the
endpoint is also willing to send EFMP packets.
A client MUST NOT use remembered value of efmp_supported for 0-RTT
connections.
Except for the cases outlined in Section 7, it is RECOMMENDED for the
server to consistently include the efmp_supported parameter. This
enables clients to utilize loss bits at their discretion.
6.3. EFMP Packet Processing
An EFMP packet is identified by the header form bit (0x80) of the
first byte of a UDP datagram payload and the 32-bit version field
with the value (0xTBD) that directly follows the first octet. Since
the EFMP payload is part of the first octet, an observer does not
need to process a packet beyond the version field.
7. Ossification Considerations
Accurate loss reporting is not critical for the operation of the QUIC
protocol, though its presence in a sufficient number of connections
is important for the operation of networks.
The use of EFMP is amenable to "greasing" described in [RFC8701] and
MUST be greased. The greasing should be accomplished similarly to
the latency Spin bit greasing in [QUIC-TRANSPORT]. Namely,
implementations MUST NOT include efmp_supported transport parameter
for a random selection of at least one in every 16 QUIC connections.
It is possible to observe packet reordering near the edge of the
square signal. A middle box might observe the signal and try to fix
packet reordering that it can identify, though only a small fraction
of reordering can be fixed using this method. The Latency Spin bit
signal edge can be used for the same purpose.
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8. Security Considerations
The measurements described in this document do not involve new
packets injected into the network causing potential harm to the
network itself and to data traffic. The measurements could be harmed
by a malicious endpoint misreporting losses or an attacker injecting
artificial traffic. In the environments where such attacks are
possible and cannot be identified by on-path observers, loss signal
should not be used for automated control of the network.
In the absence of packet loss, the Q bit signal does not provide any
information that cannot be observed by simply counting packets
transiting a network path. The L bit signal discloses internal state
of the protocol's loss detection machinery, but this state can often
be gleaned by timing packets and observing congestion controller
response. Hence, loss bits do not provide a viable new mechanism to
attack QUIC data integrity and secrecy.
8.1. Optimistic ACK Attack
A defense against an Optimistic ACK Attack [QUIC-TRANSPORT] involves
a sender randomly skipping packet numbers to detect a receiver
acknowledging packet numbers that have never been received. The Q
bit signal may inform the attacker which packet numbers were skipped
on purpose and which had been actually lost (and are, therefore, safe
for the attacker to acknowledge). To use the Q bit for this purpose,
the attacker must first receive at least an entire Q run of packets,
which renders the attack ineffective against a delay-sensitive
congestion controller.
For QUIC v1 connections, if the attacker can make its peer transmit
data using a single large stream, examining offsets in STREAM frames
can reveal whether packet number skips are deliberate. In that case,
the Q bit signal provides no new information (but it does save the
attacker the need to remove packet protection). However, an endpoint
that communicates using [DATAGRAM] and uses a loss-based congestion
controller MAY shorten the current Q run by the number of skipped
packets. For example, skipping a single packet number will invert
the sQuare signal one outgoing packet sooner.
9. Privacy Considerations
To minimize unintentional exposure of information, loss bits provide
an explicit loss signal -- a preferred way to share information per
[RFC8558].
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[QUIC-TRANSPORT] allows changing connection IDs in the middle of a
QUIC connection to reduce the likelihood of a passive observer
linking old and new subflows to the same device. Hence, a QUIC
implementation would need to reset all counters when it changes
connection ID used for outgoing packets. It would also need to avoid
incrementing Unreported Loss counter for loss of packets sent with a
different connection ID.
Accurate loss information allows identification and correlation of
network conditions upstream and downstream of the observer. This
could be a powerful tool to identify connections that attempt to hide
their origin networks, if the adversary is able to affect network
conditions in those origin networks. Similar information can be
obtained by packet timing and inferring congestion controller
response to network events, but loss information provides a clearer
signal.
Implementations MUST allow administrators of clients and servers to
disable loss reporting either globally or per QUIC connection.
Additionally, as described in Section 7, loss reporting MUST be
disabled for a certain fraction of all QUIC connections.
10. IANA Considerations
This document registers a new value in the QUIC Transport Parameter
Registry:
Value: 0xTBD (if this document is approved)
Parameter Name: efmp_supported
Specification: Indicates that the endpoint supports the explicit flow
measurement protocol. An endpoint that advertises this transport
parameter can EFMP packets. An endpoint that advertises this
transport parameter with value 1 can also send EFMP packets.
11. Change Log
TBD
12. Acknowledgments
The following people directly contributed key ideas that shaped this
draft: Kazuho Oku, Christian Huitema.
13. References
13.1. Normative References
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[AltMark] Fioccola, G., Ed., Cociglio, M., Mirsky, G., Mizrahi, T.,
and T. Zhou, "Alternate-Marking Method", RFC 9341,
DOI 10.17487/RFC9341, December 2022,
<https://www.rfc-editor.org/rfc/rfc9341>.
[EXPLICIT-MEASUREMENTS]
Cociglio, M., Ferrieux, A., Fioccola, G., Lubashev, I.,
Bulgarella, F., Nilo, M., Hamchaoui, I., and R. Sisto,
"Explicit Host-to-Network Flow Measurements Techniques",
RFC 9506, DOI 10.17487/RFC9506, October 2023,
<https://www.rfc-editor.org/rfc/rfc9506>.
[INVARIANTS]
Thomson, M., "Version-Independent Properties of QUIC",
RFC 8999, DOI 10.17487/RFC8999, May 2021,
<https://www.rfc-editor.org/rfc/rfc8999>.
[QUIC-BIT] Thomson, M., "Greasing the QUIC Bit", RFC 9287,
DOI 10.17487/RFC9287, August 2022,
<https://www.rfc-editor.org/rfc/rfc9287>.
[QUIC-TRANSPORT]
Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/rfc/rfc9000>.
[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/rfc/rfc2119>.
[RFC8558] Hardie, T., Ed., "Transport Protocol Path Signals",
RFC 8558, DOI 10.17487/RFC8558, April 2019,
<https://www.rfc-editor.org/rfc/rfc8558>.
[RFC8701] Benjamin, D., "Applying Generate Random Extensions And
Sustain Extensibility (GREASE) to TLS Extensibility",
RFC 8701, DOI 10.17487/RFC8701, January 2020,
<https://www.rfc-editor.org/rfc/rfc8701>.
[RFC9065] Fairhurst, G. and C. Perkins, "Considerations around
Transport Header Confidentiality, Network Operations, and
the Evolution of Internet Transport Protocols", RFC 9065,
DOI 10.17487/RFC9065, July 2021,
<https://www.rfc-editor.org/rfc/rfc9065>.
13.2. Informative References
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[DATAGRAM] Pauly, T., Kinnear, E., and D. Schinazi, "An Unreliable
Datagram Extension to QUIC", RFC 9221,
DOI 10.17487/RFC9221, March 2022,
<https://www.rfc-editor.org/rfc/rfc9221>.
[RFC7713] Mathis, M. and B. Briscoe, "Congestion Exposure (ConEx)
Concepts, Abstract Mechanism, and Requirements", RFC 7713,
DOI 10.17487/RFC7713, December 2015,
<https://www.rfc-editor.org/rfc/rfc7713>.
[RFC8321] Fioccola, G., Ed., Capello, A., Cociglio, M., Castaldelli,
L., Chen, M., Zheng, L., Mirsky, G., and T. Mizrahi,
"Alternate-Marking Method for Passive and Hybrid
Performance Monitoring", RFC 8321, DOI 10.17487/RFC8321,
January 2018, <https://www.rfc-editor.org/rfc/rfc8321>.
[TRAIN] Thomson, M., Huitema, C., and K. Oku, "Transparent Rate
Adaptation Indications for Networks (TRAIN) Protocol",
Work in Progress, Internet-Draft, draft-thomson-scone-
train-protocol-00, 14 October 2024,
<https://datatracker.ietf.org/doc/html/draft-thomson-
scone-train-protocol-00>.
Authors' Addresses
Alexandre Ferrieux (editor)
Orange Labs
Email: alexandre.ferrieux@orange.com
Igor Lubashev (editor)
Akamai Technologies
Email: ilubashe@akamai.com
Giuseppe Fioccola (editor)
Huawei Technologies
Email: giuseppe.fioccola@huawei.com
Marcus Ihlar (editor)
Ericsson
Email: marcus.ihlar@ericsson.com
Ferrieux, et al. Expires 1 September 2025 [Page 14]
Internet-Draft explicit-measurements February 2025
Fabio Bulgarella
Telecom Italia - TIM
Via Reiss Romoli, 274
10148 Torino
Italy
Email: fabio.bulgarella@guest.telecomitalia.it
Mauro Cociglio
Italy
Email: mauro.cociglio@outlook.com
Isabelle Hamchaoui
Orange Labs
Email: isabelle.hamchaoui@orange.com
Massimo Nilo
Telecom Italia - TIM
Via Reiss Romoli, 274
10148 Torino
Italy
Email: massimo.nilo@telecomitalia.it
Ferrieux, et al. Expires 1 September 2025 [Page 15]