Internet DRAFT - draft-fz-core-coap-pm
draft-fz-core-coap-pm
CORE Working Group G. Fioccola
Internet-Draft T. Zhou
Intended status: Standards Track Huawei
Expires: 14 September 2023 M. Cociglio
F. Bulgarella
M. Nilo
F. Milan
Telecom Italia
13 March 2023
Constrained Application Protocol (CoAP) Performance Measurement Option
draft-fz-core-coap-pm-04
Abstract
This document specifies a method for the Performance Measurement of
the Constrained Application Protocol (CoAP). A new CoAP option is
defined in order to enable network telemetry both end-to-end and hop-
by-hop. The endpoints cooperate by marking and, possibly, mirroring
information on the round-trip connection.
Status of This Memo
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This Internet-Draft will expire on 14 September 2023.
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Copyright (c) 2023 IETF Trust and the persons identified as the
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Performance Measurement methods for CoAP . . . . . . . . . . 3
2.1. sQuare bit and Spin bit . . . . . . . . . . . . . . . . . 4
2.2. Combined sQuare bit . . . . . . . . . . . . . . . . . . . 5
3. CoAP Performance Measurement Option . . . . . . . . . . . . . 5
3.1. Structure of the PM Option . . . . . . . . . . . . . . . 6
4. Application Scenarios . . . . . . . . . . . . . . . . . . . . 8
4.1. Non-proxying endpoints . . . . . . . . . . . . . . . . . 8
4.2. Collaborating proxies . . . . . . . . . . . . . . . . . . 9
4.3. Non-collaborating proxies . . . . . . . . . . . . . . . . 10
4.3.1. Non-caching proxies . . . . . . . . . . . . . . . . . 11
4.4. DTLS . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.5. OSCORE . . . . . . . . . . . . . . . . . . . . . . . . . 12
5. Management and Configuration . . . . . . . . . . . . . . . . 13
6. Congestion Control . . . . . . . . . . . . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
10.1. Normative References . . . . . . . . . . . . . . . . . . 14
10.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
In the CoAP protocol [RFC7252], reliability is provided by marking a
message as Confirmable (CON), as to be retransmitted if not
acknowledged by an ACK message. A message that does not require
reliable transmission can be sent as a Non-confirmable message (NON).
In case of CoAP reliable mode, Message IDs and ACKs could potentially
be used to measure Round-Trip Time (RTT) and losses. But it can be
resource-consuming for constrained nodes since they have to look at
Message IDs and take timestamps. These operations are expensive in
terms of resources. In case of CoAP unreliable mode, there is no ACK
and, consequently, it is not possible to measure RTT and losses.
Thus, there is no easy way to measure the performance metrics in a
CoAP environment including resource-constrained nodes. And it is in
any case limited to RTT and end-to-end losses.
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A mechanism to measure both end-to-end and hop-by-hop performance in
CoAP can be useful to verify that the operational requirements are
met, but it should be a simple mechanism for network diagnostic to be
developed on constrained nodes requiring just a minimal amount of
collaboration from the endpoints.
[I-D.ietf-ippm-explicit-flow-measurements] describes the
methodologies for Explicit Flow Measurement (EFM). The EFM
techniques employ few marking bits, inside the header of each packet,
for loss and delay measurement. These are relevant for encrypted
protocols, e.g. QUIC [RFC9000], where there are only few bits
available in the non-encrypted header in order to allow passive
performance metrics from an on-path probe. These methodologies could
potentially be used and extended in CoAP.
[I-D.ietf-ippm-explicit-flow-measurements] defines different
combinations of bits. Such flexibility is convenient when using a
protocol with a limited number of eligible bits to exploit, e.g.,
QUIC. Different alternatives have been proposed, but all these
methods together imply complex algorithms that do not apply well to
the CoAP environment.
This document aims to create an easy way to allow performance
measurement for CoAP, by defining a new option, called Performance
Measurement (PM) CoAP Option. The CoAP performance metrics (e.g.
RTT and losses) allow to perform both end-to-end and hop-by-hop
measurements and can be useful for an operator or an enterprise that
is managing a constrained, low-power and lossy network.
1.1. Requirements Language
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 RFC 2119 [RFC2119] and
RFC 8174 [RFC8174].
2. Performance Measurement methods for CoAP
The approach proposed in this document relies on a new Performance
Measurement (PM) Option for CoAP [RFC7252]. This new option is
defined in Section 3 and carries PM bits.
The PM bits that are included in the Option are:
* sQuare bit (Q bit), based on [RFC9341] and further described in
[I-D.ietf-ippm-explicit-flow-measurements];
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* Spin bit (S bit), described in [RFC9312] and included as optional
bit in [RFC9000];
* Loss and Delay event information for further usage.
A requirement to enable PM methods in CoAP environment is that the
methodologies and the algorithm needs to be kept simple. For this
reason, the idea is to re-apply only the S bit and Q bit.
Thus, the advantages of using the CoAP PM Option are:
1) Simplification because it is not needed to read Message IDs,
indeed there is a well-defined sQuare wave, and it is not
necessary to store timestamps, since the duration of the Spin Bit
period is equal to RTT.
2) Enabling easy on-path probe (proxy, gateway) metrics.
2.1. sQuare bit and Spin bit
The sQuare bit algorithm consists of creating square waves of a known
length (e.g. 64 packets). Each communicating endpoint can set the Q
bit and toggle its value each time a fixed number of messages have
been sent. The number of packets can be easily recognized and packet
loss can be measured.
The Spin bit algorithm consists of creating a square wave signal on
the data flow, using a bit, whose length is equal to RTT. The Spin
bit causes one bit to ‘spin’, generating one edge (a transition from
0 to 1 or from 1 to 0) once per end-to-end RTT. When sending a new
request, a client sets the spin bit to the opposite value it had in
the immediately previously sent request to the same server. Then,
the server echoes the same value of the spin bit of the request in
the spin bit of the response. Therefore the Spin bit is set by both
sides to the same value for as long as one round trip lasts and then
it toggles the value.
All the possible measurements (end-to-end, hop-by-hop) that are
enabled by the Q bit and S bit are detailed in
[I-D.ietf-ippm-explicit-flow-measurements].
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2.2. Combined sQuare bit
The synergy between S bit and Q bit is also possible. As described
above, the length of the Q bit square waves is fixed (e.g. a
predefined number of packets) in this way each endpoint can detect a
packet loss if it receives less packets than the other endpoint has
sent. It is possible to potentiate the Q bit signal by incorporating
RTT information as well. This implies a little modification to the
algorithm of the Q bit that could also be used alone:
A single packet in a period of the square wave can be selected and
set to the opposite value of that period. After one RTT it comes
back and another packet is selected and set again to the opposite
value of that period. And the process can start again. By
measuring the distance between these special packets, it is
possible to measure the RTT in addition to packet loss. The
periods with the special packets have one packet less than
expected but this is easy to recognize and to take into account by
both endpoints.
The Q bit and S bit signals use two single bit values and the new
signal is a Combined sQuare bit (C bit) signal. This mechanism uses
a single bit that serves two purposes: a loss indicator and a delay
indicator. It is worth highlighting that it is similar to the Delay
bit (D bit), described in [I-D.ietf-ippm-explicit-flow-measurements].
Indeed, the D bit, as enhancement of the S bit, is set only once per
RTT and a single packet with the marked Delay bit bounces between a
client and a server. The C bit value can also be seen as an
Exclusive OR operation (XOR) between the two Q bit and D bit values:
C = Q XOR D.
Since C bit incorporates both Q bit and S bit information, the same
considerations for the two separate signals in
[I-D.ietf-ippm-explicit-flow-measurements] can also be extended in
the case of C bit. Therefore, all the possible measurements (end-to-
end, hop-by-hop) that are enabled by using only C bit can be found in
[I-D.ietf-ippm-explicit-flow-measurements] by merging Q bit and S bit
derived measurements.
3. CoAP Performance Measurement Option
Figure 1 shows the property of the CoAP Performance Measurement (PM)
Option. The formatting of this table is reported in [RFC7252]. The
C, U, N, and R columns indicate the properties Critical, Unsafe,
NoCacheKey, and Repeatable as defined in [RFC7252].
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+--------+---+---+---+---+--------+--------+--------+---------+
| Number | C | U | N | R | Name | Format | Length | Default |
+========+===+===+===+===+========+========+========+=========+
| TBD | | x | - | | PM | uint | 1 | 0 |
+--------+---+---+---+---+--------+--------+--------+---------+
C=Critical, U=Unsafe, N=NoCacheKey, R=Repeatable
Figure 1: CoAP PM Option Properties
The CoAP PM Option is Elective and Proxy Unsafe. But as discussed in
Section 4.3, it MAY also be Safe-to-Forward in some implementations
with non-caching proxies.
As detailed in Section 4.5, the option can be of class U, I and E in
terms of OSCORE processing.
Note that it could be possible to make use of one bit in the option
to identify the mode. In this way two patterns can be defined.
3.1. Structure of the PM Option
The value of the PM option is a 1 byte unsigned integer. This
integer value encodes the following fields:
0
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|M| Pattern |
+-+-+-+-+-+-+-+-+
Figure 2: Value of the CoAP Performance Measurement Option
Where:
* The Mode bit (M bit) can be set to 1 or 0 and it is used to
identify whether the Option follows pattern 0 (M bit = 0) or
pattern 1 (M bit = 1).
* Pattern bits can be of two kinds as reported below.
The PM Option can employ two patterns based on the value of the M
bit:
0
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|0|Q|S| Event |
+-+-+-+-+-+-+-+-+
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Figure 3: CoAP Performance Measurement Option pattern 0
0
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|1|C| Event |
+-+-+-+-+-+-+-+-+
Figure 4: CoAP Performance Measurement Option pattern 1
The CoAP Option could be defined with 2 PM bits (S and Q) or defined
with a single PM bit (C bit).
Where:
* Q bit is used in pattern 0. It is described in
[I-D.ietf-ippm-explicit-flow-measurements];
* S bit is used in pattern 0. It is described in [RFC9312] and also
embedded in the QUIC Protocol [RFC9000];
* C bit is used in pattern 1. It is based on the enhancement of the
Q bit signal with the S bit information. The two methods are
described in [I-D.ietf-ippm-explicit-flow-measurements] and
coupled as detailed in Section 2.2;
* Event bits MAY be used to encode additional Loss and Delay
information based on well-defined encoding and they can also be
used by on-path probes. If these Event bits are all zero, they
MUST be ignored on receipt.
It is worth noting that the only differences between the two patterns
are related to the accuracy of the measurements. Further details can
be found in [I-D.ietf-ippm-explicit-flow-measurements].
The Event bits can be divided into two parts, for instance: loss
event bits and delay event bits. Based on the average RTT, an
endpoint can define different levels of thresholds and set the delay
event bits accordingly. The same applies to loss event bits. In
this way an on-path probe becomes aware of the network conditions by
simply reading these Event bits.
The on-path probe can read the event signaling bits and could be the
Proxy or the Gateway which interconnects disjointed CoAP networks.
It MAY communicate with Client and Server to set some parameters such
as timeout based on the network performance.
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The CoAP PM Option described in this document can be used in both
requests and responses. If a CoAP endpoint does not implement the
measurement methodologies, it can simply exclude the option in the
outgoing message. In this way the other CoAP endpoints become aware
that the measurement cannot be executed in that case.
The fixed number of packets to create the Q bit (or C bit) signal is
predefined and its value is configured from the beginning for all the
CoAP endpoints, as also mentioned in Section 5.
It is worth mentioning that in some specific circumstances, e.g.
CoAP clients that "observe" resources [RFC7641] or empty-ACKs, the
measurements can be done only for one direction. For bidirectional
measurements, it is required to have traffic in both directions.
4. Application Scenarios
The main usage of the CoAP PM Option is to do end-to-end measurement
between the client and the server but it can also allow on-path
measurements. The on-path measurement is the additional feature.
This information can be used to monitor the network in order to check
the operational performance and to employ further network
optimization.
The intermediaries or on-path nodes could be:
Probes that must be able to see deep into application.
Proxies that, as specified in [RFC7252], are CoAP endpoints tasked
by CoAP clients to perform requests on their behalf.
4.1. Non-proxying endpoints
The CoAP PM Option can be applied end-to-end between client and
server and, since it is Elective, it can be ignored by an endpoint
that does not understand it.
+--------+ +--------+
| Client |---------------+---------------| Server |
+--------+ | +--------+
|
probe
Figure 5: Scenario with non-proxying endpoints
The enabled measurements are:
* end-to-end loss and delay measurements between Client and Server,
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* on-path upstream and downstream loss and delay components (as
explained in [I-D.ietf-ippm-explicit-flow-measurements]) if there
is a probe (e.g. network functions).
* on-path intra-domain loss and delay portion if there are more than
one probe as a result of the difference between the computed
upstream or downstream components (as explained in
[I-D.ietf-ippm-explicit-flow-measurements]).
The on-path network probes can read Q bit and S bit (or C bit) and
implement the relevant algorithms to measure losses and RTT.
Otherwise they can simply read the Event bits and be informed about
the performance without implementing any algorithm. The event
signaling bits can be sent from the Server (that can do the
performance measurement calculation) to the Client, or viceversa.
If the CoAP PM Option is applied between client and server, a probe
can measure the total RTT by using the S bit, indeed it allows RTT
measurement for all the intermediate points. Additionally, with the
Q bit and by applying [RFC9341], it is also possible to do hop-by-hop
measurements for loss and delay and segment where possible between
the probes, according to the methodologies described in
[I-D.ietf-ippm-explicit-flow-measurements]. Alternatively, it is
possible to use the C bit to get the same information for loss and
delay as explained in [I-D.ietf-ippm-explicit-flow-measurements].
4.2. Collaborating proxies
The proxies can be collaborating and it means that they understand
and are configured to handle the CoAP PM Option. The CoAP PM Option
can be handled on the client, on the server and on each Proxies.
client-proxy proxy-proxy proxy-server
<-------> <-----------------> <------->
+--------+ +-----+ +-----+ +--------+
| Client |---+---|Proxy|--------+--------|Proxy|---+---| Server |
+--------+ | +-----+ | +-----+ | +--------+
| | |
probe probe probe
Figure 6: Scenario with collaborating proxies
In case of collaborating proxies, the enabled measurements are
different depending on where the CoAP PM Option is applied.
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It can be possible to apply the CoAP PM Option between Client and
Proxy, between the Proxies and between Proxy and Server. The
sessions are separated end-to-end between Client and Server and the
enabled measurements can be done on the separated sessions:
* loss and delay measurements between Client and Proxy, between
Proxies and between Proxy and Server,
* on-path upstream and downstream loss and delay components (as
explained in [I-D.ietf-ippm-explicit-flow-measurements]) on each
Proxy,
* on-path upstream and downstream loss and delay components (as
explained in [I-D.ietf-ippm-explicit-flow-measurements]) on each
Probe,
* end-to-end loss and delay measurements as a result of the addition
of the loss and delay contributions of the separated sessions.
* on-path intra-domain loss and delay portion as a result of the
difference between the computed upstream or downstream components
(as explained in [I-D.ietf-ippm-explicit-flow-measurements]).
So, if there are CoAP proxies, the measurement can be done between
the Proxies or between a Proxy and the Client or between a Proxy and
the Server. It can be done through Spin bit or by applying [RFC9341]
on the sQuare Bit signal. Therefore, it is also possible to do hop-
by-hop measurements for loss and delay and segment where possible
according to the methodologies described in
[I-D.ietf-ippm-explicit-flow-measurements].
4.3. Non-collaborating proxies
The proxies can be non-collaborating and this means that they do not
handle the CoAP PM Option. The CoAP PM Option can be applied end-to-
end between client and server.
There are some issues that may occur in case of non-collaborating
proxies. In general, since CoAP proxies hide the identity of the
client, the data would appear mixed after the proxy in the presence
of more than one client doing the measurements. Similarly, since
CoAP proxies could also apply caching, it can happen to receive mixed
signals in the presence of cache entries.
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In case of collaborating proxies, these issues are solved because the
measurements can be segmented and done between the Client and a Proxy
or between the Proxies or between a Proxy and the Server. In this
case, it could be possible for the proxy to still use the PM Option
for the bundle of clients for a specific server.
While, in case of non-collaborating proxies, it is RECOMMENDED to use
the Option only for a single client and a single server at once in
order to avoid that traffic from different clients would be mixed.
But, if the proxy has also cached data, the data can be reordered and
mixed, so that they cannot be used for measurement. For this reason,
the PM Option is defined as Proxy Unsafe and it is intended to be
unsafe for forwarding by a proxy that does not understand it. In
conclusion, if there are non-collaborating and caching proxies, the
measurements would not be possible.
4.3.1. Non-caching proxies
An implementation MAY consider the PM Option as Safe-to-Forward if
the proxies are non-caching in general or in the only case the PM
Option is included in the message.
client-server
<--------------------------------------------->
+--------+ +-----+ +-----+ +--------+
| Client |---+---|Proxy|--------+--------|Proxy|---+---| Server |
+--------+ | +-----+ | +-----+ | +--------+
| | |
probe probe probe
Figure 7: Scenario with non-collaborating and non-caching proxies
In case of non-collaborating and non-caching proxies, proxies MAY be
configured to handle the PM Option as Safe-to-Forward, and it means
that not recognized option MUST be forwarded. Therefore, the enabled
measurements for a single client and a single server at once can be:
* end-to-end loss and delay measurements between Client and Server,
* on-path upstream and downstream loss and delay components (as
explained in [I-D.ietf-ippm-explicit-flow-measurements]) on each
Probe,
* on-path intra-domain loss and delay portion as a result of the
difference between the computed upstream or downstream components
(as explained in [I-D.ietf-ippm-explicit-flow-measurements]).
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4.4. DTLS
CoAP can be secured using Datagram TLS (DTLS) [RFC6347] over UDP and
it can prevent on-path measures in case of non-proxying endpoints.
When a client uses a collaborating proxy the sessions client-proxy,
proxy-proxy, proxy-server are secured using DTLS, but the separated
sessions can still be measured. An on-path probe cannot perform the
measurements in any case.
4.5. OSCORE
The CoAP PM Option can be used with OSCORE [RFC8613]. Since an
OSCORE message may contain both an Inner and an Outer instance of a
certain CoAP message field, the CoAP PM Option can be an Inner option
or an Outer option based on the specific applications and required
security and privacy. Then network administrators can put their
measurement probes in one or more places to break down the different
RTT and loss contributions where it is relevant (e.g. at the ingress/
egress of their respective network segments).
Inner options (Class E) are used to communicate directly with the
other endpoint and are encrypted and integrity protected. If the
CoAP PM Option is sent as Inner Option, it only enables end-to-end
measurements in all the cases. In case of collaborating proxies the
separated sessions client-proxy, proxy-proxy, proxy-server cannot be
measured.
Outer options (Class U or I) are intended to be used to support proxy
operations and are unprotected or integrity protected only. If the
CoAP PM Option is sent as Outer Option, it allows both end-to-end and
on-path measurements by enabling hop-by-hop and segmented loss and
delay measurements on the proxies.
If an OSCORE endpoint sends both outer and inner option, the inner is
for measuring the connection to the end-to-end peer, and the outer
can be used for measuring the connection to next proxy.
if the PM option is used as an Outer Option, it may also be
integrity-protected, to be reliably processed and this would require
using also DTLS or an OSCORE association with a proxy
[I-D.tiloca-core-oscore-capable-proxies].
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5. Management and Configuration
The measurement points can perform RTT and packet loss calculation
without the need of any Network Management System (NMS) to collect
information. It may be possible that the measurement points inform
the NMS if there are particular network conditions (e.g. high packet
loss or high RTT). For some parameters (e.g. 64 packets sQuare Bit
signal), it is assumed static configuration on the client. There are
several alternatives for the implementation but this is out of scope
of this document.
6. Congestion Control
As specified in Section 4.7 of [RFC7252], clients (including proxies)
have to strictly limit the number of simultaneous outstanding
interactions that they maintain to a given server (including proxies)
to NSTART. The default value of NSTART is 1 but a value for NSTART
greater than one is also possible. The CoAP PM Option implementation
must not affect CoAP congestion control mechanisms.
7. Security Considerations
Security considerations related to CoAP proxying are discussed in
[RFC7252].
A CoAP endpoint can use the CoAP PM Option to affect the measures of
a network into which it is making requests by maliciously specifying
a wrong option value. Also, the PM bits may reveal performance
information outside the administrative domain. To prevent that, a
CoAP proxy that is located at the boundary of an administrative
domain MAY be instructed to strip the payload or part of it before
forwarding the message.
It is worth highlighting what happens if devices, transport network
and server are operated by different administrative domains.
Security concerns need to be taken into account.
CoAP can be used with DTLS [RFC6347] and it can prevent on-path
measures by on-path probes while it is still possible to do
measurements on collaborating proxies, as explained above.
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CoAP can also be used with OSCORE [RFC8613] and the CoAP PM options
can be integrity protected end-to-end by OSCORE. In this case, as
explained above and differently from DTLS, the CoAP PM can easily
work with OSCORE. OSCORE ensures end-to-end integrity protection and
would tell the endpoints if someone tampered with the option vlaue,
but it doesn't mean that the endpoints are not lying to the probe.
However it is possible to assume that for the typical CoAP
applications it is less likely that the endpoints are attackers while
it is more likely that an on-path probe is the attacker.
8. IANA Considerations
IANA is requested to add the following entry to the "CoAP Option
Numbers" sub-registry available at https://www.iana.org/assignments/
core-parameters/core-parameters.xhtml#option-numbers:
Number Name Reference
---------------------------------------------
TBD PM Option [This draft]
Figure 8: CoAP PM Option Numbers
9. Acknowledgements
The authors would like to thank Christian Amsüss, Carsten Bormann,
Marco Tiloca, Thomas Fossati for the precious comments and
suggestions.
10. References
10.1. Normative 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>.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014,
<https://www.rfc-editor.org/info/rfc7252>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
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[RFC8613] Selander, G., Mattsson, J., Palombini, F., and L. Seitz,
"Object Security for Constrained RESTful Environments
(OSCORE)", RFC 8613, DOI 10.17487/RFC8613, July 2019,
<https://www.rfc-editor.org/info/rfc8613>.
[RFC9341] 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/info/rfc9341>.
10.2. Informative References
[I-D.ietf-ippm-explicit-flow-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",
Work in Progress, Internet-Draft, draft-ietf-ippm-
explicit-flow-measurements-03, 13 March 2023,
<https://datatracker.ietf.org/api/v1/doc/document/draft-
ietf-ippm-explicit-flow-measurements/>.
[I-D.tiloca-core-oscore-capable-proxies]
Tiloca, M. and R. Höglund, "OSCORE-capable Proxies", Work
in Progress, Internet-Draft, draft-tiloca-core-oscore-
capable-proxies-05, 13 March 2023,
<https://datatracker.ietf.org/api/v1/doc/document/draft-
tiloca-core-oscore-capable-proxies/>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <https://www.rfc-editor.org/info/rfc6347>.
[RFC7641] Hartke, K., "Observing Resources in the Constrained
Application Protocol (CoAP)", RFC 7641,
DOI 10.17487/RFC7641, September 2015,
<https://www.rfc-editor.org/info/rfc7641>.
[RFC9000] 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/info/rfc9000>.
[RFC9312] Kühlewind, M. and B. Trammell, "Manageability of the QUIC
Transport Protocol", RFC 9312, DOI 10.17487/RFC9312,
September 2022, <https://www.rfc-editor.org/info/rfc9312>.
Authors' Addresses
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Giuseppe Fioccola
Huawei
Riesstrasse, 25
80992 Munich
Germany
Email: giuseppe.fioccola@huawei.com
Tianran Zhou
Huawei
156 Beiqing Rd.
Beijing
100095
China
Email: zhoutianran@huawei.com
Mauro Cociglio
Telecom Italia
Via Reiss Romoli, 274
10148 Torino
Italy
Email: mauro.cociglio@outlook.com
Fabio Bulgarella
Telecom Italia
Via Reiss Romoli, 274
10148 Torino
Italy
Email: fabio.bulgarella@guest.telecomitalia.it
Massimo Nilo
Telecom Italia
Via Reiss Romoli, 274
10148 Torino
Italy
Email: massimo.nilo@telecomitalia.it
Fabrizio Milan
Telecom Italia
Via Reiss Romoli, 274
10148 Torino
Italy
Email: fabrizio.milan@telecomitalia.it
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