rfc9583xml2.original.xml   rfc9583.xml 
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<rfc ipr="trust200902" category="info" docName="draft-irtf-qirg-quantum-internet <rfc xmlns:xi="http://www.w3.org/2001/XInclude" ipr="trust200902" category="info
-use-cases-19"> " number="9583" docName="draft-irtf-qirg-quantum-internet-use-cases-19" obsolete
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<front> <front>
<title abbrev=" Quantum Internet Application Scenarios">Application Scenario <title abbrev="Quantum Internet Application Scenarios">Application Scenarios
s for the Quantum Internet</title> for the Quantum Internet</title>
<seriesInfo name="RFC" value="9583"/>
<author initials="C." surname="Wang" fullname="Chonggang Wang"> <author initials="C." surname="Wang" fullname="Chonggang Wang">
<organization>InterDigital Communications, LLC</organization> <organization>InterDigital Communications, LLC</organization>
<address> <address>
<postal> <postal>
<street>1001 E Hector St</street> <street>1001 E Hector St</street>
<city>Conshohocken</city> <city>Conshohocken</city>
<region>PA</region>
<code>19428</code> <code>19428</code>
<country>USA</country> <country>United States of America</country>
<region></region>
</postal> </postal>
<phone></phone>
<email>Chonggang.Wang@InterDigital.com</email> <email>Chonggang.Wang@InterDigital.com</email>
<uri></uri>
</address> </address>
</author> </author>
<author initials="A." surname="Rahman" fullname="Akbar Rahman"> <author initials="A." surname="Rahman" fullname="Akbar Rahman">
<organization>Ericsson</organization> <organization>Ericsson</organization>
<address> <address>
<postal> <postal>
<street>349 Terry Fox Drive</street> <street>349 Terry Fox Drive</street>
<city>Ottawa Ontario</city> <city>Ottawa</city>
<region>Ontario</region>
<code>K2K 2V6</code> <code>K2K 2V6</code>
<country>Canada</country> <country>Canada</country>
<region></region>
</postal> </postal>
<phone></phone>
<email>Akbar.Rahman@Ericsson.Com</email> <email>Akbar.Rahman@Ericsson.Com</email>
<uri></uri>
</address> </address>
</author> </author>
<author initials="R." surname="Li" fullname="Ruidong Li"> <author initials="R." surname="Li" fullname="Ruidong Li">
<organization>Kanazawa University</organization> <organization>Kanazawa University</organization>
<address> <address>
<postal> <postal>
<street>Kakuma-machi</street> <street>Kakumamachi, Kanazawa</street>
<city>Kanazawa City</city> <region>Ishikawa</region>
<code>Ishikawa Prefecture 920-1192</code> <code>920-1192</code>
<country>Japan</country> <country>Japan</country>
<region></region>
</postal> </postal>
<phone></phone>
<email>lrd@se.kanazawa-u.ac.jp</email> <email>lrd@se.kanazawa-u.ac.jp</email>
<uri></uri>
</address> </address>
</author> </author>
<author initials="M." surname="Aelmans" fullname="Melchior Aelmans">
<author initials="M." surname="Aelmans" fullname="Melchior Aelmans"> <organization>Juniper Networks</organization>
<organization>Juniper Networks</organization> <address>
<address> <postal>
<postal> <street>Boeing Avenue 240</street>
<street>Boeing Avenue 240</street> <city>Schiphol-Rijk</city>
<city>Schiphol-Rijk</city> <code>1119 PZ</code>
<code>1119 PZ</code> <country>Netherlands</country>
<country>The Netherlands</country> </postal>
<region/> <email>maelmans@juniper.net</email>
</postal> </address>
<phone/> </author>
<email>maelmans@juniper.net</email> <author initials="K." surname="Chakraborty" fullname="Kaushik Chakraborty">
<uri/>
</address>
</author>
<author initials="K." surname="Chakraborty" fullname="Kaushik Chakraborty
">
<organization>The University of Edinburgh</organization> <organization>The University of Edinburgh</organization>
<address> <address>
<postal> <postal>
<street>10 Crichton Street</street> <street>10 Crichton Street</street>
<city>Edinburgh</city> <city>Edinburgh, Scotland</city>
<code>EH8 9AB, Scotland</code> <code>EH8 9AB</code>
<country>UK</country> <country>United Kingdom</country>
<region></region>
</postal> </postal>
<phone></phone>
<email>kchakrab@exseed.edu.ac.uk</email> <email>kchakrab@exseed.edu.ac.uk</email>
<uri></uri>
</address> </address>
</author> </author>
<date year="2023" month="October" day="16"/> <date year="2024" month="May"/>
<area>Internet Research Task Force (IRTF)</area>
<workgroup>QIRG</workgroup> <workgroup>QIRG</workgroup>
<!-- [rfced] Please insert any keywords (beyond those that appear in the
title) for use on https://www.rfc-editor.org/search.
-->
<keyword>example</keyword>
<abstract> <abstract>
<t> <t>The Quantum Internet has the potential to improve application
The Quantum Internet has the potential to improve application fun functionality by incorporating quantum information technology into the
ctionality by incorporating quantum information infrastructure of the overall Internet. This document provides an
technology into the infrastructure of the overall Internet. This overview of some applications expected to be used on the Quantum
document provides an overview of some applications Internet and categorizes them. Some general requirements for the Quantum
expected to be used on the Quantum Internet and categorizes them. Internet are also discussed. The intent of this document is to describe
Some general a framework for applications and to describe a few selected application
requirements for the Quantum Internet are also discussed. The int scenarios for the Quantum Internet. This document is a product of the
ent of this document is to describe a Quantum Internet Research Group (QIRG).</t>
framework for applications, and describe a few selected applicati
on scenarios for the Quantum Internet.This document
is a product of the Quantum Internet Research Group (QIRG).
</t>
</abstract> </abstract>
</front> </front>
<middle> <middle>
<section anchor="sec_introduction" numbered="true" toc="default">
<name>Introduction</name>
<t>The Classical, i.e., non-quantum, Internet has been constantly
growing since it first became commercially popular in the early 1990s.
It essentially consists of a large number of end nodes (e.g., laptops,
smart phones, and network servers) connected by routers and clustered in
Autonomous Systems. The end nodes may run applications that provide
service for the end users such as processing and transmission of voice,
video, or data.
<section anchor="sec:introduction" title="Introduction"> <!--[rfced] Is it correct that "fiber optics" is listed for both "backbone
links" and "access links", or is an update needed?
<t>
The Classical, i.e., non-quantum, Internet has been constantly growin
g since it first became commercially popular in the early 1990's. It essentiall
y consists
of a large number of end nodes (e.g., laptops, smart phones, netw
ork servers) connected by routers and clustered in Autonomous Systems.
The end nodes may run applications that provide service for the e
nd users such as processing and transmission of voice, video or data.
The connections between the various nodes in the Internet include
backbone links (e.g., fiber optics) and access
links (e.g., fiber optics, WiFi, cellular wireless, Digital Subsc
riber Lines (DSLs)). Bits are transmitted across the Classical Internet in packe
ts.
</t>
<t>
Research and experiments have picked up over the last few years for deve
loping the Quantum Internet <xref target="Wehner" />.
End nodes will also be part of the Quantum Internet, in that case
called quantum end nodes that may be connected by quantum repeaters/routers.
These quantum end nodes will also run value-added applications wh
ich will be discussed later.
</t>
<t> Original:
The physical layer quantum channels between the various nodes in The connections
the Quantum Internet can be either waveguides such as optical fibers or free spa between the various nodes in the Internet include backbone links
ce. (e.g., fiber optics) and access links (e.g., fiber optics, WiFi,
Photonic channels are particularly useful because light (photons) cellular wireless, Digital Subscriber Lines (DSLs)).
is very suitable for physically realizing qubits. The Quantum Internet will ope -->
rate
according to quantum physical principles such as quantum superpos
ition and entanglement <xref target="RFC9340" />.
</t>
<t> The connections between the various nodes in the
The Quantum Internet is not anticipated to replace, but rather to Internet include backbone links (e.g., fiber optics) and access links
enhance the Classical Internet and/or provide breakthrough applications. For in (e.g., fiber optics, Wi-Fi, cellular wireless, and Digital Subscriber Line
stance, s
quantum key distribution can improve the security of the Classica (DSLs)). Bits are transmitted across the Classical Internet in packets.
l Internet; quantum computing can expedite and optimize computation-intensive ta </t>
sks <t>Research and experiments have picked up over the last few years for
in the Classical Internet. The Quantum Internet will run in developing the Quantum Internet <xref target="Wehner"
conjunction with the Classical Internet. The process of integrati format="default"/>. End nodes will also be a part of the Quantum
ng the Quantum Internet with the Classical Internet; in that case, they are called "quantum end nodes" and may be con
Internet is similar to the process of introducing any new communi nected by
cation and networking quantum repeaters/routers. These quantum end nodes will also run
paradigm into the existing Internet, but with more profound impli value-added applications, which will be discussed later.
cations. </t>
</t> <t>The physical layer quantum channels between the various nodes in the
<t> Quantum Internet can be either waveguides, such as optical fibers, or free
The intent of this document is to provide a common understanding space. Photonic channels are particularly useful because light
and framework of applications (photons) is very suitable for physically realizing qubits. The Quantum
and application scenarios for the Quantum Internet. It is noted t Internet will operate according to quantum physical principles such as
hat ITU-T SG13-TD158/WP3 <xref target="ITUT"/> briefly describes four kinds of u quantum superposition and entanglement <xref target="RFC9340"
se cases of quantum format="default"/>.
networks beyond quantum key distribution networks: quantum time s </t>
ynchronization use cases, quantum computing use cases, quantum random number gen <t>The Quantum Internet is not anticipated to replace but rather to
erator use cases, and quantum enhance the Classical Internet and/or provide breakthrough
communication use cases (e.g., quantum digital signatures, quantu applications. For instance, quantum key distribution can improve the
m anonymous transmission, and quantum money). This document focuses on quantum a security of the Classical Internet, and quantum computing can expedite and
pplications that have more impact on networking such as secure communication set optimize computation-intensive tasks in the Classical Internet. The
up, blind quantum computing, Quantum Internet will run in conjunction with the Classical
and distributed quantum computing; although these applications we Internet. The process of integrating the Quantum Internet with the
re mentioned in <xref target="ITUT"/>, this document gives more details and deri Classical Internet is similar to the process of introducing any new
ves some requirements from networking perspective. communication and networking paradigm into the existing Internet but
with more profound implications.
</t>
<t>The intent of this document is to provide a common understanding and
framework of applications and application scenarios for the Quantum
Internet. It is noted that ITU-T SG13-TD158/WP3 <xref target="ITUT"
format="default"/> briefly describes four kinds of use cases of quantum
networks beyond quantum key distribution networks: quantum time
synchronization use cases, quantum computing use cases, quantum random
number generator use cases, and quantum communication use cases (e.g.,
quantum digital signatures, quantum anonymous transmission, and quantum
money). This document focuses on quantum applications that have more
impact on networking, such as secure communication setup, blind quantum
computing, and distributed quantum computing; although these
applications were mentioned in <xref target="ITUT" format="default"/>,
this document gives more details and derives some requirements from
a networking perspective.
</t> </t>
<t>This document was produced by the Quantum Internet Research
Group (QIRG). It was discussed on the QIRG mailing list and during several
meetings of the research group. It has been reviewed extensively by the
QIRG members with expertise in both quantum physics and Classical
Internet operation. This document represents the consensus of the QIRG
members, of both experts in the subject matter (from the quantum and
networking domains) and newcomers, who are the target audience. It is
not an IETF product and is not a standard.
</t>
</section>
<section anchor="sec_acronyms" numbered="true" toc="default">
<name>Terms and Acronyms List</name>
<t>This document was produced by the Quantum Internet Research Group(QI <!--[rfced] To improve the readability and avoid awkward hyphenation, may
RG). It was discussed on the QIRG mailing list and several meetings of the Resea we update this sentence as follows?
rch Group. It has been reviewed extensively by the QIRG members with expertise i
n
both quantum physics and classical Internet operation. This docum
ent represents the consensus of the QIRG members, of both experts in the subject
matter (from the quantum and networking domains) and newcomers who are the targ
et audience.
It is not an IETF product and is not a standard.
</t>
</section> Original:
This document assumes that the reader is familiar with the quantum
information technology related terms and concepts that are described
in [RFC9340].
<section anchor="sec:acronyms" title="Terms and Acronyms List"> Perhaps:
<t> This document assumes that the reader is familiar with the terms and
This document assumes that the reader is familiar with the quantu concepts that relate to quantum information technology described
m information technology related terms and concepts that are in [RFC9340].
described in <xref target="RFC9340" />. In addition, the followi -->
ng terms and acronyms are defined herein for clarity:
<t>This document assumes that the reader is familiar with the quantum
information technology related terms and concepts that are described in
<xref target="RFC9340" format="default"/>. In addition, the following
terms and acronyms are defined herein for clarity:
</t> </t>
<t> <!--[rfced] FYI, we have ordered the terminology list in Section 2
<list style="symbols"> alphabetically. Please review and let us know of any concerns.
<t>Bell Pairs – A special type of two-qubits quantum stat -->
e. The two qubits show a correlation that cannot be observed in classical inform
ation theory.
We refer to such correlation as quantum entanglement.
Bell pairs exhibit the maximal quantum entanglement. One example of a Bell pair
is (|00>+|11>)/(Sqrt(2)).
The Bell pairs are a fundamental resource for quantum
communication. </t>
<t>Bit - Binary Digit (i.e., fundamental unit of informat
ion in classical communications and classical computing).
Bit is used in Classical Internet where the stat
e of a bit is deterministic. In contrast, Qubit is used in Quantum Internet
where the state of a qubit is uncertain
before it is measured. </t>
<t>Classical Internet - The existing, deployed Internet ( <!--[rfced] To clarify "two-qubits", may we update the text as follows?
circa 2020) where bits are transmitted in packets between nodes to convey inform
ation.
The Classical Internet supports applications which may
be enhanced by the Quantum Internet. For example, the end-to-end security of a
Classical Internet application may be improved by secu
re communication setup using a quantum application. Classical Internet is a netw
ork
of classical network nodes which do not support q
uantum information technology. In contrast, Quantum Internet consists of quantum
nodes based on
quantum information technology. </t>
<!--<t>DSL - Digital Subscriber Line</t>--> Current:
<!--<t>GUI - Graphical User Interface</t>--> Bell Pairs: A special type of two-qubits quantum state.
<t>Entanglement Swapping: It is a process of sharing an e
ntanglement between two distant parties via some intermediate nodes. For example
, suppose there are three parties A, B, C,
and each of the parties (A, B) and (B, C) share Bell pair
s. B can use the qubits it shares with A and C to perform entanglement swapping
operations, and as a result,
A and C share Bell pairs. Entanglement swapping essential
ly realizes entanglement distribution (i.e., two nodes in distance can share a B
ell pair). </t>
<t>Fast Byzantine Negotiation - A Quantum-based method fo Perhaps:
r fast agreement in Byzantine negotiations <xref target="Ben-Or" /> <xref target Bell Pairs: A special type of quantum state that is two qubits.
="Taherkhani" />. </t> -->
<!--<t>Hybrid Internet - The "new" or evolved Internet to
be formed due to a merger of the Classical Internet and the Quantum Internet.</
t> -->
-&gt; <dl spacing="normal">
<t>Local Operations and Classical Communication (LOCC) - <dt>Bell Pairs:</dt><dd>A special type of two-qubits quantum state. Th
A method where nodes communicate in rounds, in which (1) they can send any class e two
ical qubits show a correlation that cannot be observed in classical
information to each other; (2) they can perform local information theory. We refer to such correlation as quantum
quantum operations individually; and (3) the actions performed in each round ca entanglement. Bell pairs exhibit the maximal quantum
n depend entanglement. One example of a Bell pair is
on the results from previous rounds. </t> (|00&gt;+|11&gt;)/(Sqrt(2)). The Bell pairs are a fundamental
resource for quantum communication.</dd>
<dt>Bit:</dt><dd>Binary digit (i.e., fundamental unit of information i
n
classical communications and classical computing). Bit is used in
the Classical Internet where the state of a bit is deterministic. In
contrast, qubit is used in the Quantum Internet where the state of a
qubit is uncertain before it is measured.</dd>
<dt>Classical Internet:</dt><dd>The existing, deployed Internet (circa
2020)
where bits are transmitted in packets between nodes to convey
information. The Classical Internet supports applications that may
be enhanced by the Quantum Internet. For example, the end-to-end
security of a Classical Internet application may be improved by
a secure communication setup using a quantum application. Classical
Internet is a network of classical network nodes that do not
support quantum information technology. In contrast, Quantum
Internet consists of quantum nodes based on quantum information
technology.</dd>
<!--<t>DSL - Digital Subscriber Line</t>-->
<!--<t>GUI - Graphical User Interface</t>-->
<dt>Entanglement Swapping:</dt><dd>It is a process of sharing an
entanglement between two distant parties via some intermediate
nodes. For example, suppose that there are three parties (A, B, and C)
and that each of the parties (A, B) and (B, C) share Bell pairs. B
can use the qubits it shares with A and C to perform entanglement-swap
ping operations, and as a result, A and C share Bell
pairs.
<t>Noisy Intermediate-Scale Quantum (NISQ) - NISQ was def <!--[rfced] We are having difficulty parsing "two nodes in distance".
ined in <xref target="Preskill"/> to represent a near-term era in quantum techno How should the text be updated for clarity?
logy.
According to this definition, NISQ computers have two sal
ient features: (1) The size of NISQ computers range from 50 to a few hundred phy
sical qubits
(i.e., intermediate-scale); and (2) Qubits in NISQ comput
ers have inherent errors and the control over them is imperfect (i.e., noisy).</
t>
<t> Packet - A self-identified message with in-band addre Original:
sses or other information that can be used for forwarding the message. The messa Entanglement swapping essentially realizes entanglement
ge contains distribution (i.e., two nodes in distance can share a Bell pair).
an ordered set of bits of determinate number. The bits co
ntained in a packet are classical bits. </t>
<!--<t>Packet - Formatted unit of multiple related bits.
The bits contained in a packet may be classical bits, or the measured state of q
ubits expressed in classical bits.</t> -->
<t>Prepare-and-Measure - A set of Quantum Internet scenar
ios where quantum nodes only support simple quantum functionalities (i.e., prepa
re qubits and measure qubits).
For example, BB84 <xref target="BB84"/> is a prepare-and-
measure quantum key distribution protocol.
</t>
<t>Quantum Computer (QC) - A quantum end node that also h
as quantum memory and quantum computing capabilities is regarded as a full-fledg
ed quantum
computer.</t>
<t>Quantum End Node - An end node that hosts user applica Perhaps:
tions and interfaces with the rest of the Internet. Typically, an end node may Entanglement swapping essentially realizes entanglement
serve in a client, distribution (i.e., two nodes separated in distance can share a
server, or peer-to-peer role as part of the application. Bell pair).
A quantum end node must also be able to interface to the Classical Internet for -->
control
purposes and thus also be able to receive, process, and t
ransmit classical bits/packets.</t>
<t>Quantum Internet - A network of Quantum Networks. Entanglement swapping essentially realizes entanglement
The Quantum Internet is expected to be merged into the Classical Internet. distribution (i.e., two nodes in distance can share a Bell
The Quantum Internet may either improve classical applic pair).</dd>
ations or may enable new quantum applications.</t> <dt>Fast Byzantine Negotiation:</dt><dd>A Quantum-based method for
fast agreement in Byzantine negotiations <xref target="Ben-Or"
format="default"/> <xref target="Taherkhani"
format="default"/>.</dd>
<!--<t>Hybrid Internet - The "new" or evolved Internet to be formed due
to a merger of the Classical Internet and the Quantum Internet.</t> -->
<dt>Local Operations and Classical Communication (LOCC):</dt><dd>A
method where nodes communicate in rounds, in which (1) they can send
any classical information to each other, (2) they can perform local
quantum operations individually, and (3) the actions performed in
each round can depend on the results from previous rounds.</dd>
<dt>Noisy Intermediate-Scale Quantum (NISQ):</dt><dd>NISQ was
defined in <xref target="Preskill" format="default"/> to represent a
near-term era in quantum technology. According to this definition,
NISQ computers have two salient features: (1) the size of NISQ
computers range from 50 to a few hundred physical qubits (i.e.,
intermediate-scale) and (2) qubits in NISQ computers have inherent
errors and the control over them is imperfect (i.e., noisy).</dd>
<dt>Packet:</dt><dd>A self-identified message with in-band addresses
or other information that can be used for forwarding the
message. The message contains an ordered set of bits of determinate
number. The bits contained in a packet are classical bits.</dd>
<!--<t>Packet - Formatted unit of multiple related bits. The bits contai
ned in a packet may be classical bits, or the measured state of qubits expressed
in classical bits.</t> -->
<dt>Prepare and Measure:</dt><dd>A set of Quantum Internet scenarios w
here
quantum nodes only support simple quantum functionalities (i.e.,
prepare qubits and measure qubits). For example, BB84 <xref
target="BB84" format="default"/> is a prepare-and-measure quantum
key distribution protocol.</dd>
<dt>Quantum Computer (QC):</dt><dd>A quantum end node that also has
quantum memory and quantum computing capabilities is regarded as a
full-fledged quantum computer.</dd>
<dt>Quantum End Node:</dt><dd>An end node that hosts user
applications and interfaces with the rest of the Internet.
Typically, an end node may serve in a client, server, or
peer-to-peer role as part of the application. A quantum end node
must also be able to interface to the Classical Internet for control
purposes and thus be able to receive, process, and transmit
classical bits/packets.</dd>
<dt>Quantum Internet:</dt><dd>A network of Quantum Networks. The
Quantum Internet is expected to be merged into the Classical
Internet. The Quantum Internet may either improve classical
applications or enable new quantum applications.</dd>
<dt>Quantum Key Distribution (QKD):</dt><dd>A method that leverages
quantum mechanics such as a no-cloning theorem to let two parties
create the same arbitrary classical key.</dd>
<!--<t>Quantum Key Distribution (QKD) - A method that leverages quantum
mechanics such as no-cloning theorem to let two parties (e.g., a sender and a re
ceiver) securely establish/agree on a key.</t> -->
<dt>Quantum Network:</dt><dd>A new type of network enabled by quantum
information technology where quantum resources, such as qubits and
entanglement, are transferred and utilized between quantum nodes.
The Quantum Network will use both quantum channels and classical
channels provided by the Classical Internet, referred to as a "hybrid
implementation".</dd>
<!--<t>Quantum Network - A new type of network enabled by quantum inform
ation technology where qubits are transmitted between nodes to convey informatio
n.(Note: qubits must be sent individually and not in packets). The Quantum Netwo
rk will use both quantum channels, and classical channels provided by the Classi
cal Internet.</t>-->
<dt>Quantum Teleportation:</dt><dd>A technique for transferring
quantum information via Local Operations and Classical Communication
(LOCC). If two parties share a Bell pair, then by using quantum
teleportation, a sender can transfer a quantum data bit to a receiver
without sending it physically via a quantum channel.</dd>
<dt>Qubit:</dt><dd>Quantum bit (i.e., fundamental unit of
information in quantum communication and quantum computing).
<t>Quantum Key Distribution (QKD) - A method that leverag <!--[rfced] In this sentence, "is denoted as its basis state vector |0> or |1>"
es quantum mechanics such as no-cloning theorem to let two parties create the sa is unclear. May we update the text as follows?
me arbitrary classical key.</t>
<!--<t>Quantum Key Distribution (QKD) - A method that lev
erages quantum mechanics such as no-cloning theorem to let two parties (e.g., a
sender and a receiver) securely establish/agree on a key.</t> -->
<t>Quantum Network - A new type of network enabled by qua Original:
ntum information technology where quantum resources such as qubits and entanglem It is similar to a
ent are transferred and classic bit in that the state of a qubit is either "0" or "1"
utilized between quantum nodes. The Quantum Network will after it is measured, and is denoted as its basis state vector |0>
use both quantum channels, and classical channels provided by the Classical Int or |1> using Dirac's ket notation.
ernet, referred to as
a hybrid implementation. </t>
<!--<t>Quantum Network - A new type of network enabled b
y quantum information technology where qubits are transmitted between nodes to c
onvey information.
(Note: qubits must be sent individually and not in packet
s). The Quantum Network will use both quantum channels, and classical channels p
rovided
by the Classical Internet.</t>-->
<t>Quantum Teleportation - A technique for transferring q Perhaps:
uantum information via local operations and classical communication (LOCC). If t It is similar to a
wo parties share a Bell pair, classic bit in that the state of a qubit is either "0" or "1"
then using quantum teleportation a sender can transfer a after it is measured and denotes its basis state vector as |0>
quantum data bit to a receiver without sending it physically via a quantum chann or |1> using Dirac's ket notation.
el. -->
</t>
<t>Qubit - Quantum Bit (i.e., fundamental unit of informa
tion in quantum communication and quantum computing). It is similar to a classi
c bit in that the state of a qubit
is either "0" or "1" after it is measured, and is denoted
as its basis state vector |0> or |1> using Dirac's ket notation. However, the
qubit is different than a classic bit in that
the qubit can be in a linear combination of both states b
efore it is measured and termed to be in superposition. Any of several Degrees o
f Freedom (DOF) of a photon
(e.g., polarization, time bib, and/or frequency) or an el
ectron (e.g., spin) can be used to encode a qubit.</t>
<!--<t>VoIP - Voice Over IP</t>-->
<t>Transmit a Qubit - An operation of encoding a qubit in
to a mobile carrier (i.e., typically photon) and passing it through a quantum ch
annel from
a sender (a transmitter) to a receiver.</t>
<t>Teleport a Qubit - An operation on two or more carrier
s in succession to move a qubit from a sender to a receiver using quantum telepo
rtation. </t>
<t>Transfer a Qubit - An operation to move a qubit from a
sender to a receiver without specifying the means of moving the qubit, which co
uld be “transmit” or “teleport”.</t>
</list>
</t>
It is
similar to a classic bit in that the state of a qubit is either "0"
or "1" after it is measured and is denoted as its basis state
vector |0&gt; or |1&gt; using Dirac's ket notation. However, the
qubit is different than a classic bit in that the qubit can be in a
linear combination of both states before it is measured and termed
to be in superposition. Any of several Degrees of Freedom (DOF) of a
photon (e.g., polarization, time bib, and/or frequency) or an
electron (e.g., spin) can be used to encode a qubit.</dd>
<!--<t>VoIP - Voice Over IP</t>-->
<dt>Teleport a Qubit:</dt><dd>An operation on two or more carriers in
succession to move a qubit from a sender to a receiver using quantum
teleportation.</dd>
<dt>Transfer a Qubit:</dt><dd>An operation to move a qubit from a send
er to
a receiver without specifying the means of moving the qubit, which
could be "transmit" or "teleport".</dd>
<dt>Transmit a Qubit:</dt><dd>An operation to encode a qubit into a mo
bile
carrier (i.e., typically photon) and pass it through a quantum
channel from a sender (a transmitter) to a receiver.</dd>
</dl>
</section> </section>
<section anchor="sec_applications" numbered="true" toc="default">
<name>Quantum Internet Applications</name>
<t>The Quantum Internet is expected to be beneficial for a subset of
existing and new applications. The expected applications for the
Quantum Internet are still being developed as we are in the formative
stages of the Quantum Internet <xref target="Castelvecchi"
format="default"/> <xref target="Wehner" format="default"/>. However,
an initial (and non-exhaustive) list of the applications to be supported
on the Quantum Internet can be identified and classified using two
different schemes. Note that this document does not include quantum
computing applications that are purely local to a given node.
<!--We use "applications" in the widest sense of the word and include
functionality typically contained in Layers 4 (Transport) to Layers 7
(Application) of the Open System Interconnect (OSI) model. -->
</t>
<t>Applications may be grouped by the usage that they serve.
Specifically, applications may be grouped according to the following
categories:
</t>
<dl spacing="normal">
<dt>Quantum cryptography applications:</dt><dd>Refer to the use of
quantum information technology for cryptographic tasks (e.g.,
quantum key distribution <xref target="Renner"
format="default"/>).</dd>
<dt>Quantum sensor applications:</dt><dd>Refer to the use of
quantum information technology for supporting distributed sensors
(e.g., clock synchronization <xref target="Jozsa2000"
format="default"/> <xref target="Komar" format="default"/> <xref
target="Guo" format="default"/>).</dd>
<dt>Quantum computing applications:</dt><dd>Refer to the use of
quantum information technology for supporting remote quantum
computing facilities (e.g., distributed quantum computing <xref
target="Denchev" format="default"/>).</dd>
</dl>
<t>This scheme can be easily understood by both a technical and
non-technical audience. The next sections describe the scheme in more
detail.
</t>
<section anchor="sec_typeofquantumcrypto" numbered="true" toc="default">
<name>Quantum Cryptography Applications</name>
<t> Examples of quantum cryptography applications include quantum-based
secure communication setup and fast Byzantine negotiation.
</t>
<dl spacing="normal">
<dt>Secure communication setup:</dt><dd>Refers to secure
cryptographic key distribution between two or more end nodes. The
most well-known method is referred to as "Quantum Key Distribution (QK
D)"
<xref target="Renner" format="default"/>.</dd>
<dt>Fast Byzantine negotiation:</dt><dd>Refers to a Quantum-based
method for fast agreement in Byzantine negotiations <xref
target="Ben-Or" format="default"/>, for example, to reduce the
number of expected communication rounds and, in turn, to achieve
faster agreement, in contrast to classical Byzantine negotiations. A
quantum-aided Byzantine agreement on quantum repeater networks as
proposed in <xref target="Taherkhani" format="default"/> includes
optimization techniques to greatly reduce the quantum circuit depth
and the number of qubits in each node. Quantum-based methods for
fast agreement in Byzantine negotiations can be used for improving
consensus protocols such as practical Byzantine Fault
Tolerance (pBFT) as well as other distributed computing features
that use Byzantine negotiations.</dd>
<dt>Quantum money:</dt><dd>Refers to the main security requirement of
money is
unforgeability.
<section anchor="sec:applications" title="Quantum Internet Applications"> <!--[rfced] We are having difficulty understanding "aims to fulfill".
May we update this sentence?
<t> Original:
The Quantum Internet is expected to be beneficial for a subset of A quantum money scheme aims to fulfill by
existing and new applications. exploiting the no-cloning property of the unknown quantum states.
The expected applications for the Quantum Internet are still bein
g developed as we are in the formative stages
of the Quantum Internet <xref target="Castelvecchi" /> <xref targ
et="Wehner" />. However, an initial
(and non-exhaustive) list of the applications to be supported on
the Quantum Internet can be identified and
classified using two different schemes. Note, this document does
not include quantum computing applications that are purely
local to a given node.
<!--We use "applications" in the widest sense of the word and inc
lude functionality typically contained in Layers 4
(Transport) to Layers 7 (Application) of the Open System Intercon
nect (OSI) model. -->
</t>
<t>Applications may be grouped by the usage that they serve. Spe Perhaps:
cifically, A quantum money scheme aims to exploit the no-cloning property of
applications may be grouped according to the following categories the unknown quantum states.
: -->
<list style="symbols">
<t>Quantum cryptography applications - Refer to the use o
f quantum information technology for cryptographic tasks
(e.g., quantum key distribution <xref target="Renner" />)
.</t>
<t>Quantum sensors applications - Refer to the use of qua
ntum information technology for supporting
distributed sensors (e.g., clock synchronization <xref ta
rget="Jozsa2000"/> <xref target="Komar" /> <xref target="Guo" /> ).</t>
<t>Quantum computing applications - Refer to the use of q
uantum information technology for
supporting remote quantum computing facilities (e.g., dis
tributed quantum computing <xref target="Denchev" />).</t>
</list> A quantum money scheme aims to fulfill by exploiting
the no-cloning property of the unknown quantum states. Though the
original idea of quantum money dates back to 1970, these early
protocols allow only the issuing bank to verify a quantum
banknote. However, the recent protocols such as public key quantum
money <xref target="Zhandry" format="default"/> allow anyone to
verify the banknotes locally.</dd>
</dl>
</section>
<section anchor="sec_typeofquantumsensor" numbered="true" toc="default">
<name>Quantum Sensing/Metrology Applications</name>
<t>The entanglement, superposition, interference, and squeezing of
properties can enhance the sensitivity of the quantum sensors and
eventually can outperform the classical strategies. Examples of
quantum sensor applications include network clock synchronization,
high-sensitivity sensing, etc. These applications mainly leverage a
network of entangled quantum sensors (i.e., quantum sensor networks)
for high-precision, multiparameter estimation <xref target="Proctor"
format="default"/>.
</t>
<dl spacing="normal">
<dt>Network clock synchronization:</dt><dd>Refers to a world wide
set of high-precision clocks connected by the Quantum Internet to
achieve an ultra precise clock signal <xref target="Komar"
format="default"/> with fundamental precision limits set by quantum
theory.</dd>
<dt>High-sensitivity sensing:</dt><dd>Refers to applications that
leverage quantum phenomena to achieve reliable nanoscale sensing of
physical magnitudes. For example, <xref target="Guo"
format="default"/> uses an entangled quantum network for measuring
the average phase shift among multiple distributed nodes.</dd>
<!--<t>Quantum imaging - The highly sensitive quantum sensors show
great potential in improving the domain of
magnetoencephalography. Unlike the current classical
strategies, with the help of a network of quantum sensors, it
is possible to measure the magnetic fields generated by the
flow of current through neuronal assemblies in the brain while
the subject is moving. It reveals the dynamics of the networks
of neurons inside the human brain on a millisecond
timescale. This kind of imaging capability could improve the
diagnosis and monitoring the conditions like
attention-deficit-hyperactivity disorder <xref target="Hill"
/>. </t> -->
<dt>Interferometric telescopes using quantum information:</dt><dd>
Refers to interferometric techniques that are used to combine signals
from two or
more telescopes to obtain measurements with higher resolution than
what could be obtained with either telescope individually. It can
make measurements of very small astronomical objects if the
telescopes are spread out over a wide area. However, the phase
fluctuations and photon loss introduced by the communication
channel between the telescopes put a limitation on the baseline
lengths of the optical interferometers. This limitation can
potentially be avoided using quantum teleportation. In general, by
sharing EPR-pairs using quantum repeaters, the optical
interferometers can communicate photons over long distances,
providing arbitrarily long baselines <xref target="Gottesman2012"
format="default"/>.</dd>
</dl>
</section>
<section anchor="sec_typeofquantumcomputing" numbered="true" toc="default"
>
<name>Quantum Computing Applications</name>
<t>In this section, we include the applications for the quantum
computing. It's anticipated that quantum computers as a cloud service
will become more available in future. Sometimes, to run such
applications in the cloud while preserving the privacy, a client and a
server need to exchange qubits (e.g., in blind quantum computation
<xref target="Fitzsimons" format="default"/> as described
below). Therefore, such privacy preserving quantum computing
applications require a Quantum Internet to execute. </t>
<t> Examples of quantum computing include distributed quantum
computing and blind quantum computing, which can enable new types of
cloud computing.
</t>
<dl spacing="normal">
<dt>Distributed quantum computing:</dt><dd>Refers to a collection
of small-capacity, remote quantum computers (i.e., each supporting
a relatively small number of qubits) that are connected and work
together in a coordinated fashion so as to simulate a virtual
large capacity quantum computer <xref target="Wehner"
format="default"/>.</dd>
This scheme can be easily understood by both a technical <!-- [rfced] We are having trouble parsing "over" in the sentence
and non-technical audience. below. May we remove it or update "over" to "using"?
The next sections describe the scheme in more detail.
</t>
<section anchor="sec:typeofquantumcrypto" title="Quantum Current:
Cryptography Applications"> Blind quantum computing: Private, or blind, quantum
<t> Examples of quantum cryptography applications computation, which provides a way for a client to delegate a
include quantum-based secure communication setup and fast Byzantine negotiation computation task to one or more remote quantum computers without
. disclosing the source data to be computed over [Fitzsimons].
<list style="numbers">
<t>Secure communication setup - Refers to
secure cryptographic key distribution between two or more end nodes.
The most well-known method is referred to
as Quantum Key Distribution (QKD) <xref target="Renner" />.</t>
<t>Fast Byzantine negotiation - Refers to Perhaps A:
a Quantum-based method for fast agreement in Byzantine negotiations <xref targe Blind quantum computing: Private, or blind, quantum
t="Ben-Or" />, for example, computation, which provides a way for a client to delegate a
to reduce the number of expected communic computation task to one or more remote quantum computers without
ation rounds and in turn achieve faster agreement, in contrast to classical Byza disclosing the source data to be computed [Fitzsimons].
ntine negotiations. A quantum aided Byzantine agreement
on quantum repeater networks as proposed
in <xref target="Taherkhani" /> includes optimization techniques to greatly redu
ce the quantum circuit depth and the number of qubits in each node.
Quantum-based methods for fast agreement
in Byzantine negotiations can be used for improving consensus protocols such as
practical Byzantine
Fault Tolerance(pBFT), as well as other d
istributed computing features which use Byzantine negotiations.</t>
<t>Quantum money - The main security requ Perhaps B:
irement of money is unforgeability. A quantum money scheme aims to fulfill by ex Blind quantum computing: Private, or blind, quantum
ploiting the no-cloning property of the unknown quantum computation, which provides a way for a client to delegate a
states. Though the original idea of quant computation task to one or more remote quantum computers without
um money dates back to 1970, these early protocols allow only the issuing bank t disclosing the source data to be computed using [Fitzsimons].
o verify a quantum banknote. However, the recent protocols -->
such as public-key quantum money <xref ta
rget ="Zhandry" /> allow anyone to verify the banknotes locally.</t>
</list>
</t>
</section>
<section anchor="sec:typeofquantumsensor" title="Quantum <dt>Blind quantum computing:</dt><dd>Refers to private, or blind,
Sensing/Metrology Applications"> quantum computation, which provides a way for a client to delegate
<t> The entanglement, superposition, interference a computation task to one or more remote quantum computers without
, squeezing properties can enhance the sensitivity of the quantum sensors and ev disclosing the source data to be computed over <xref
entually can outperform the classical target="Fitzsimons" format="default"/>.</dd>
strategies. Examples of quantum sensor applic <!-- <t>Quantum chemistry - Quantum chemistry is one of the most
ations include network clock synchronization, high sensitivity sensing, etc. The promising quantum computing applications that can outperform
se applications mainly the classical strategy using only a few hundred qubits quantum
leverage a network of entangled quantum s computers. Using the NISQ devices, the quantum algorithms
ensors (i.e. quantum sensor networks) for high-precision multi-parameter estimat manage to determine the molecular energies of the small
ion <xref target="Proctor" />. molecules within chemical accuracy <xref target="YudongCao"
<list style="numbers"> />. However, due to the short coherence time of the quantum
<t>Network clock synchronization - Refers devices, it is still difficult to simulate larger
to a world wide set of high-precision clocks connected by the Quantum Internet molecules.</t>-->
to achieve an ultra </dl>
precise clock signal <xref target="Komar" </section>
/> with fundamental precision limits set by quantum theory.</t> <!--<section anchor="sec:classification" title="Control vs Data Plane
<t>High sensitivity sensing - Refers to a Classification"> <t>The majority of routers currently used in the
pplications that leverage quantum phenomena to achieve reliable nanoscale sensin Classical Internet separate control plane functionality and data
g of plane functionality for, amongst other reasons, stability, capacity
physical magnitudes. For example, <xref t and security. In order to classify applications for the Quantum
arget="Guo" /> uses an entangled quantum network for measuring the average phase Internet, a somewhat similar distinction can be made. Specifically
shift among multiple some applications can be classified as being responsible for
distributed nodes.</t> initiating sessions and performing other control plane
<!--<t>Quantum imaging - The highly sensi functionality (including management functionalities too). Other
tive quantum sensors show great potential in improving the domain of magnetoence applications carry application or user data and can be classified
phalography. Unlike the current classical strategies, as data plane functionality. </t>
with the help of a network of quantum sen
sors, it is possible to measure the magnetic fields generated by the flow of cur
rent through neuronal assemblies in
the brain while the subject is moving. It
reveals the dynamics of the networks of neurons inside the human brain on a mil
lisecond timescale. This kind of
imaging capability could improve the diag
nosis and monitoring the conditions like attention-deficit-hyperactivity disorde
r <xref target="Hill" />. </t> -->
<t> Interferometric Telescopes using Quan
tum Information - Interferometric techniques are used to combine signals from tw
o or more telescopes to obtain
measurements with higher resolution than
what could be obtained with either telescope individually. It can make measureme
nts of very small astronomical
objects if the telescopes are spread out
over a wide area. However, the phase fluctuations and photon loss introduced by
the communication channel between
the telescopes put a limitation on the ba
seline lengths of the optical interferometers. This limitation can be potentiall
y avoided using quantum teleportation.
In general, by sharing EPR-pairs using qu
antum repeaters, the optical interferometers can communicate photons over long d
istances, providing arbitrarily
long baselines <xref target="Gottesman201
2" />. </t>
</list>
</t>
</section>
<section anchor="sec:typeofquantumcomputing" title="Quant <t>Some examples of what may be called control plane applications
um Computing Applications"> in the Classical Internet are Domain Name Server (DNS), Session
<t> In this section, we include the applications Information Protocol (SIP), and Internet Control Message Protocol
for the quantum computing. It's anticipated that quantum computers as a cloud se (ICMP). Furthermore, examples of data plane applications are
rvice will become more available in future. E-mail, web browsing, and video streaming. Note that some
Sometimes, to run such applications in the cl applications may require both control plane and data plane
oud while preserving the privacy, a client and a server need to exchange qubits functionality. For example, a Voice over IP (VoIP) application may
(e.g., in blind quantum use SIP to set up the call and then transmit the VoIP user packets
computation <xref target="Fitzsimons"/> a over the data plane to the other party. </t>
s described below). Therefore, such privacy preserving quantum computing applica
tions require a Quantum Internet to execute. </t>
<t> Examples of quantum computing include distrib
uted quantum computing and blind quantum computing, which can
enable new types of cloud computing.
<list style="numbers">
<t>Distributed quantum computing - Refers
to a collection of remote small-capacity quantum computers (i.e., each supporti
ng a relatively small number of qubits)
that are connected and work together in a
coordinated fashion so as to simulate a virtual large capacity
quantum computer <xref target="Wehner" />
.</t>
<t>Blind quantum computing - Refers to pr <t>Similarly, nodes in the Quantum Internet applications may also use
ivate, or blind, quantum computation, the classification paradigm of control plane functionality versus data
which provides a way for a client to dele plane functionality where: <list style="symbols"> <t>Control Plane -
gate a computation task to one or more remote quantum computers without disclosi Network functions and processes that operate on (1) control
ng the source data bits/packets or qubits (e.g., to setup up end-user encryption); or (2)
to be computed over <xref target="Fitzsim management bits/packets or qubits (e.g., to configure nodes). For
ons"/>.</t> example, a quantum ping could be implemented as a control plane
application to test and verify if there is a quantum connection
between two quantum nodes. Another example is quantum superdense
coding (which is used to transmit two classical bits by sending only
one qubit). Quantum superdense coding can be leveraged to implement a
secret sharing application to share secrets between two parties <xref
target="Wang" />. This secret sharing application based on quantum
superdense encoding can be classified as control plane
functionality.</t>
<!-- <t>Quantum chemistry - Quantum chemi <t>Data Plane - Network functions and processes that operate on
stry is one of the most promising quantum computing applications that can outper end-user application bits/packets or qubits (e.g., voice, video,
form the classical strategy using only a few hundred data). Sometimes also referred to as the "user plane". For example, a
qubits quantum computers. Using the NISQ data plane application can be video conferencing, which uses QKD-based
devices, the quantum algorithms manage to determine the molecular energies of th secure communication setup (which is a control plane function) to
e small molecules within share a classical secret key for encrypting and decrypting video
chemical accuracy <xref target="YudongCao frames.</t> </list>
" />. However, due to the short coherence time of the quantum devices, it is sti
ll difficult to simulate larger molecules. </t>
-->
</list>
</t>
</section>
<!-- </t> <t> As shown in the table in <xref target="fig:controldataplane"
<section anchor="sec:classification" title="Control vs Data Plane />, control and data plane applications vary for different types of
Classification"> networks. For a standalone Quantum Network (i.e., that is not
integrated into the Internet), entangled qubits are its "data" and
thus entanglement distribution can be regarded as its data plane
application, while the signalling for controlling entanglement
distribution be considered as control plane. However, looking at the
Quantum Internet, QKD-based secure communication setup, which may be
based on and leverage entanglement distribution, is in fact a control
plane application, while video conference using QKD-based secure
communication setup is a data plane application. In the future, two
data planes may exist, respectively for Quantum Internet and Classical
Internet, while one control plane can be leveraged for both Quantum
Internet and Classical Internet. </t>
</section> -->
<t>The majority of routers currently used in the Classica </section>
l Internet separate control plane functionality and data plane functionality for <section anchor="sec_usecases" numbered="true" toc="default">
, <name>Selected Quantum Internet Application Scenarios</name>
amongst other reasons, stability, capacity and security. <t>The Quantum Internet will support a variety of applications and
In order to classify applications for the Quantum Internet, a somewhat similar deployment configurations. This section details a few key application
distinction can be made. Specifically some applications scenarios that illustrate the benefits of the Quantum Internet. In
can be classified as being responsible for initiating sessions and performing ot system engineering, an application scenario is typically made up of a
her set of possible sequences of interactions between nodes and users in a
control plane functionality (including management functio particular environment and related to a particular goal. This will be
nalities too). Other applications carry application or user data and can be cla the definition that we use in this section.
ssified as </t>
data plane functionality. <section anchor="sec_usecase1" numbered="true" toc="default">
</t> <name>Secure Communication Setup</name>
<t>In this scenario, two nodes (e.g., quantum node A and quantum node
B) need to have secure communications for transmitting confidential
information (see <xref target="fig_securecom" format="default"/>).
For this purpose, they first need to securely share a classic secret
cryptographic key (i.e., a sequence of classical bits), which is
triggered by an end user with local secure interface to quantum node
A. This results in a quantum node A securely establishing a classical
secret key with a quantum node B. This is referred to as a "secure
communication setup". Note that quantum nodes A and B may be either a
bare-bone quantum end node or a full-fledged quantum computer. This
application scenario shows that the Quantum Internet can be leveraged
to improve the security of Classical Internet applications.
</t>
<t>One requirement for this secure communication setup process is that
it should not be vulnerable to any classical or quantum computing
attack. This can be realized using QKD, which is unbreakable in
principle. QKD can securely establish a secret key between two
quantum nodes, using a classical authentication channel and insecure
quantum channel without physically transmitting the key through the
network and thus achieving the required security. However, care must
be taken to ensure that the QKD system is safe against physical side-cha
nnel attacks that can compromise the system. An example of a
physical side-channel attack is to surreptitiously inject additional
light into the optical devices used in QKD to learn side information
about the system such as the polarization. Other specialized physical
attacks against QKD also use a classical authentication channel and
an insecure quantum channel such as the phase-remapping attack, photon
number splitting attack, and decoy state attack <xref
target="Zhao2018" format="default"/>. QKD can be used for many other
cryptographic communications, such as IPsec and Transport Layer
Security (TLS), where involved parties need to establish a shared
security key, although it usually introduces a high latency.
</t>
<t>QKD is the most mature feature of quantum information
technology and has been commercially released in small-scale and
short-distance deployments. More QKD use cases are described in the ETSI
document <xref target="ETSI-QKD-UseCases" format="default"/>; in
addition, interfaces between QKD users and QKD
devices are specified in the ETSI document <xref target="ETSI-QKD-Interf
aces"
format="default"/>.
</t>
<t>In general, the prepare-and-measure QKD protocols (e.g., <xref
target="BB84" format="default"/>) without using entanglement work as
follows:
</t>
<ol spacing="normal" type="1">
<t>Some examples of what may be called control plane appl <!-- [rfced] For clarity, may we update "X, Y" to "X and Y"?
ications in the Classical Internet are Domain Name Server (DNS),
Session Information Protocol (SIP), and Internet Control
Message Protocol (ICMP). Furthermore, examples of data plane
applications are E-mail, web browsing, and video streamin
g. Note that some applications may require both control plane
and data plane functionality. For example, a Voice over I
P (VoIP) application may use SIP to set up the call and then
transmit the VoIP user packets over the data plane to the
other party.
</t>
<t>Similarly, nodes in the Quantum Internet applications Current:
may also use the classification paradigm of control plane functionality Basically,
versus data plane functionality where: the node A generates two random classical bit strings X, Y.
<list style="symbols">
<t>Control Plane - Network functions and processe
s that operate on (1) control bits/packets or qubits (e.g., to setup up end-user
encryption); or (2) management bits/packets or qu
bits (e.g., to configure nodes). For example, a quantum ping could be implemente
d
as a control plane application to test and verify
if there is a quantum connection between two quantum nodes.
Another example is quantum superdense coding (whi
ch is used to transmit two classical bits by sending only one qubit). Quantum su
perdense
coding can be leveraged to implement a secret sha
ring application
to share secrets between two parties <xref target
="Wang" />. This secret sharing application based on quantum superdense encoding
can be classified
as control plane functionality.</t>
<t>Data Plane - Network functions and processes t Perhaps:
hat operate on end-user application bits/packets or qubits (e.g., voice, video, Basically,
data). Sometimes also referred to as the user pla the node A generates two random classical bit strings X and Y.
ne. For example, a data plane application can be video conferencing, which -->
uses QKD-based secure communication setup (which
is a control plane function) to share a classical secret key for encrypting
and decrypting video frames.</t>
</list>
</t> <li>The quantum node A encodes classical bits to qubits. Basically,
the node A generates two random classical bit strings X, Y. Among
them, it uses the bit string X to choose the basis and uses Y to
choose the state corresponding to the chosen basis. For example, if
X=0, then in case of the BB84 protocol, Alice prepares the state in
{|0&gt;, |1&gt;}-basis; otherwise, she prepares the state in {|+&gt;,
|-&gt;}-basis. Similarly, if Y=0, then Alice prepares the qubit
as either |0&gt; or |+&gt; (depending on the value of X); and if Y =1,
then Alice prepares the qubit as either |1&gt; or |-&gt;.</li>
<li>The quantum node A sends qubits to the quantum node B via a
quantum channel.</li>
<li>The quantum node B receives qubits and measures each of them in
one of the two bases at random.</li>
<li>The quantum node B informs the quantum node A of its choice of
bases for each qubit.</li>
<li>The quantum node A informs the quantum node B which random
quantum basis is correct.</li>
<li>Both nodes discard any measurement bit under different quantum
bases, and the remaining bits could be used as the secret key.
Before generating the final secret key, there is a post-processing
procedure over authenticated classical channels. The classical
post-processing part can be subdivided into three steps, namely
parameter estimation, error correction, and privacy
amplification. In the parameter estimation phase, both Alice and Bob
use some of the bits to estimate the channel error.
<t> As shown in the table in <xref target="fig:controldat <!-- [rfced] For clarity, may we update "abort... otherwise move" to "abort...
aplane" />, control and data plane applications vary for different types of netw or otherwise move"?
orks.
For a standalone Quantum Network (i.e., that is not integ
rated into the Internet), entangled qubits are its "data" and thus entanglement
distribution can be
regarded as its data plane application, while the signall
ing for controlling entanglement distribution be considered as control plane.
However, looking at the Quantum Internet, QKD-based secur
e communication setup, which may be based on and leverage entanglement distribut
ion, is
in fact a control plane application, while video conferen
ce using QKD-based secure communication setup is a data plane application.
In the future, two data planes may exist, respectively fo
r Quantum Internet and Classical Internet, while one control plane can be levera
ged for
both Quantum Internet and Classical Internet.
</t>
</section> --> Current:
If it is
larger than some threshold value, they abort the protocol
otherwise move to the error-correction phase.
</section> Perhaps:
If it is
larger than some threshold value, they abort the protocol
or otherwise move to the error-correction phase.
-->
<section anchor="sec:usecases" title="Selected Quantum Internet Applicati If it is larger
on Scenarios"> than some threshold value, they abort the protocol otherwise move to
the error-correction phase. Basically, if an eavesdropper tries to
intercept and read qubits sent from node A to node B, the
eavesdropper will be detected due to the entropic uncertainty
relation property theorem of quantum mechanics. As a part of the
post-processing procedure, both nodes usually also perform
information reconciliation <xref target="Elkouss" format="default"/>
for efficient error correction and/or conduct privacy amplification
<xref target="Tang" format="default"/> for generating the final
information-theoretical secure keys.</li>
<li>The post-processing procedure needs to be performed over an
authenticated classical channel. In other words, the quantum node A
and the quantum node B need to authenticate the classical channel to
make sure there is no eavesdroppers or man-in-the-middle attacks,
according to certain authentication protocols such as that described i
n <xref
target="Kiktenko" format="default"/>. In <xref target="Kiktenko"
format="default"/>, the authenticity of the classical channel is
checked at the very end of the post-processing procedure instead of
doing it for each classical message exchanged between the quantum
node A and the quantum node B.</li>
</ol>
<t>It is worth noting that:
</t>
<ol spacing="normal" type="1">
<li>There are many enhanced QKD protocols based on <xref
target="BB84" format="default"/>.
<t>The Quantum Internet will support a variety of applications an <!-- [rfced] For clarity, may we add "concerning" before "these attacks"?
d deployment configurations. This section details
a few key application scenarios which illustrates the benefits
of the Quantum Internet. In system engineering, an application scenario
is typically made up of a set of possible sequences of interac
tions between nodes and users in a particular
environment and related to a particular goal. This will be th
e definition that we use in this section.
</t>
<section anchor="sec:usecase1" title="Secure Communication Setup" Current:
> For example, a series of loopholes have been identified due to the
<t> imperfections of measurement devices; there are several solutions
In this scenario, two nodes (e.g., quantum node A and qua to take into account these attacks such as measurement-device-
ntum node B) need to have secure independent QKD [Zheng2019].
communications for transmitting confidential information
(see <xref target="fig:securecom" />).
For this purpose, they first need to securely share a cla
ssic secret cryptographic key (i.e., a sequence of classical bits),
which is triggered by an end user with local secure inter
face to quantum node A. This results in a quantum node A
to securely establish a classical secret key with a quantum node
B.
This is referred to as a secure communication setup. Note
that quantum nodes A and B may be either
a bare-bone quantum end node or a full-fledged quantum co
mputer. This application scenario shows that the Quantum Internet
can be leveraged to improve the security of Classical Int
ernet applications.
</t>
<t> Perhaps:
One requirement for this secure communication setup proce For example, a series of loopholes have been identified due to the
ss is that it should not be vulnerable to any imperfections of measurement devices; there are several solutions
classical or quantum computing attack. This can be reali to take into account concerning these attacks such as measurement-
zed using QKD which is unbreakable in principle. device-independent QKD [Zheng2019].
QKD can securely establish a secret key between two quant -->
um nodes, using a classical authentication channel and insecure quantum channel
without physically transmitting the key through the netwo
rk and thus achieving the required security.
However, care must be taken to ensure that the QKD system
is safe against physical side channel attacks which can compromise the
system. An example of a physical side channel attack is
to surreptitiously inject additional light
into the optical devices used in QKD to learn side inform
ation about the system such as the polarization.
Other specialized physical attacks against QKD also use a
classical authentication channel and insecure
quantum channel such as the phase-remapping attack,
photon number splitting attack, and decoy state attack <x
ref target="Zhao2018" />. QKD can be used for many other cryptographic communica
tions, such as IPSec and
Transport Layer Security (TLS) where involved parties nee
d to establish a shared security key, although it usually introduces a high late
ncy.
</t>
<t> For example, a series of loopholes
QKD is the most mature feature of the quantum information have been identified due to the imperfections of measurement
technology, and has been commercially released in devices; there are several solutions to take into account these
small-scale and short-distance deployments. More QKD use attacks such as measurement-device-independent QKD <xref
cases are described in ETSI documents <xref target="ETSI-QKD-UseCases" />; in ad target="Zheng2019" format="default"/>. These enhanced QKD protocols
dition, the ETSI document can work differently than the steps of BB84 protocol <xref
<xref target="ETSI-QKD-Interfaces" /> specifies interface target="BB84" format="default"/>.</li>
s between QKD users and QKD devices.
</t>
<t> <li>For large-scale QKD, QKD Networks (QKDNs) are required, which can
In general, the prepare and measure QKD protocols (e. be regarded as a subset of a Quantum Internet. A QKDN may consist of
g., <xref target="BB84"/>) without using entanglement work as follows: a QKD application layer, a QKD network layer, and a QKD link layer
<list style="numbers"> <xref target="Qin" format="default"/>. One or multiple trusted QKD
<t> The quantum node A encodes classical bits to relays <xref target="Zhang2018" format="default"/> may exist between
qubits. Basically, the node A generates two random classical bit strings X, Y. A the quantum node A and the quantum node B, which are connected by a
mong them, it uses the bit QKDN. Alternatively, a QKDN may rely on entanglement distribution
string X to choose the basis and uses Y to choose and entanglement-based QKD protocols; as a result,
the state corresponding to the chosen basis. For example, if X=0 then in case o quantum-repeaters/routers instead of trusted QKD relays are needed
f BB84 protocol Alice prepares the state for large-scale QKD. Entanglement swapping can be leveraged to
in {|0>, |1>}-basis; otherwise she prepares the s realize entanglement distribution.</li>
tate in {|+>, |->}-basis. Similarly, if Y=0 then Alice prepares the qubit either
|0> or |+> (depending on the value of X),
and if Y =1, then Alice prepares the qubit either
|1> or |->.</t>
<t> The quantum node A sends qubits to the quantu
m node B via quantum channel.</t>
<t> The quantum node B receives qubits and measur
es each of them in one of the two basis at random. </t>
<t> The quantum node B informs the quantum node A
of its choice of basis for each qubit.</t>
<t> The quantum node A informs the quantum node B
which random quantum basis is correct.</t>
<t> Both nodes discard any measurement bit under
different quantum basis and remaining bits could be used as the secret key.
Before generating the final secret key, there is
a post-processing procedure over authenticated classical channels. The classical
post-processing part can be subdivided
into three steps, namely parameter estimation, er
ror-correction, and privacy amplification. In the parameter estimation phase, bo
th Alice and Bob use some of the bits to
estimate the channel error. If it is larger than
some threshold value, they abort the protocol otherwise move to the error-correc
tion phase.
Basically, if an eavesdropper tries to intercept
and read qubits sent from node A to node B, the eavesdropper will be detected du
e to
the entropic uncertainty relation property theore
m of quantum mechanics. As a part of the post-processing procedure, both nodes u
sually also perform information reconciliation <xref target="Elkouss"/>
for efficient error correction and/or conduct pri
vacy amplification <xref target="Tang"/> for generating the final information-th
eoretical secure keys. </t>
<t> The post-processing procedure needs to be per <!-- In general, there could be three types of QKD solutions: 1)
formed over an authenticated classical channel. In other words, the quantum node Basic QKD: In this case, QKD only works for two directly
A and the quantum node B need connected quantum nodes within a short distance or a network
to authenticate the classical channel to make sur segment; If both nodes are long-distanced, trusted nodes will
e there is no eavesdroppers or man-in-the-middle attacks, according to certain a be needed for relaying multiple basic QKDs between two faraway
uthentication protocols such as <xref target=" Kiktenko"/>. quantum nodes; 2) E2E QKD: In this case, based on long-distance
In <xref target=" Kiktenko"/>, the authenticity o qubit transmission, QKD works for two faraway quantum nodes to
f the classical channel is checked at the very end of the post-processing proced provide the end-to-end security without relying on trusted
ure instead of doing it for each classical message exchanged nodes; and 3) Advanced E2E QKD: In this case, two quantum nodes
between the quantum node A and the quantum node B are far away from each other but long-distance qubit
. transmission may not be available. Instead, QKD leverages
</t> entanglement distribution or quantum repeaters (not trusted
</list> nodes) to achieve the end-to-end security.
</t> -->
<t> <!--<t> Although the addresses of Source Quantum Node A and
It is worth noting that: Destination Quantum Node B could be identified and exposed, the
<list style="numbers"> identity of users, who will use the secret cryptographic key for
<t> There are many enhanced QKD protocols based secure communications, will not necessarily be exposed during QKD
on <xref target="BB84"/>. For example, a series of loopholes have been identifie process. In other words, there is no direct mapping from the
d due to the imperfections of measurement devices; addresses of quantum nodes to the user identity; as a result, QKD
there are several solutions to take into acc protocols do not disclose user identities. </t>-->
ount these attacks such as measurement-device-independent QKD <xref target="Zhan
g2019"/>. These enhanced QKD protocols can work differently than the steps
of BB84 protocol <xref target="BB84"/>.
</t>
<t> For large-scale QKD, QKD Networks (QKDN) are
required, which can be regarded as a subset of a Quantum Internet. A QKDN may
consist of a QKD application layer, a QKD network layer, and a QKD link layer <x
ref target="Qin"/>.
One or multiple trusted QKD relays <xref tar
get="Zhang2018"/> may exist between the quantum node A and the quantum node B, w
hich are connected by a QKDN. Alternatively, a QKDN may rely on
entanglement distribution and entangleme
nt-based QKD protocols; as a result, quantum-repeaters/routers instead of truste
d QKD relays are needed for large-scale QKD.
Entanglement swapping can be leveraged t
o realize entanglement distribution.
</t>
<!-- In general, there could be three types of Q <li>QKD provides an information-theoretical way to share secret keys
KD solutions: 1) Basic QKD: In this case, QKD only works for two directly connec between two parties (i.e., a transmitter and a receiver) in the
ted quantum nodes within a short distance or a network segment; presence of an eavesdropper. However, this is true in theory, and
If both nodes are long-distanced, trusted no there is a significant gap between theory and practice. By exploiting
des will be needed for relaying multiple basic QKDs between two faraway quantum the imperfection of the detectors, Eve can gain information about the
nodes; 2) E2E QKD: In this case, based on long-distance qubit transmission, shared key <xref target="Xu" format="default"/>. To avoid such
QKD works for two faraway quantum nodes side-channel attacks in <xref target="Lo" format="default"/>, the
to provide the end-to-end security without relying on trusted nodes; and 3) Adva researchers provide a QKD protocol called "Measurement
nced E2E QKD: In this case, Device-Independent (MDI)" QKD that allows two users (a transmitter
two quantum nodes are far away from each "Alice" and a receiver "Bob") to communicate with perfect security,
other but long-distance qubit transmission may not be available. Instead, QKD l even if the (measurement) hardware they are using has been tampered
everages entanglement distribution with (e.g., by an eavesdropper) and thus is not trusted. It is
or quantum repeaters (not trusted nodes) achieved by measuring correlations between signals from Alice and Bob,
to achieve the end-to-end security. rather than the actual signals themselves.</li>
-->
<!--<t> Although the addresses of Source Quantum <li>QKD protocols based on Continuous Variable QKD (CV-QKD) have recently
Node A and Destination Quantum Node B could be identified and exposed, the iden seen plenty of interest as they only require telecommunications
tity of users, who will use equipment that is readily available and is also in common use
the secret cryptographic key for secure communications, wil industry-wide. This kind of technology is a potentially
l not necessarily be exposed during QKD process. In other words, there is no dir high-performance technique for secure key distribution over limited
ect mapping distances. The recent demonstration of CV-QKD shows compatibility
from the addresses of quantum nodes to t with classical coherent detection schemes that are widely used for
he user identity; as a result, QKD protocols do not disclose user identities. high-bandwidth classical communication systems <xref
</t>--> target="Grosshans" format="default"/>. Note that we still do not have
<t> QKD provides an information-theoretical way a quantum repeater for the continuous variable systems; hence, these
to share secret keys between two parties (i.e., a transmitter and a receiver) in kinds of QKD technologies can be used for the short distance
the presence of an eavesdropper. However, this is true in theory, and there is communications or trusted relay-based QKD networks.</li>
a significant gap
between theory and practice. By exploiting t
he imperfection of the detectors Eve can gain information about the shared key <
xref target="Xu" />.
To avoid such side-channel attacks in <x
ref target="Lo" />, the researchers provide a QKD protocol called Measurement De
vice-Independent (MDI) QKD that allows two
users (a transmitter “Alice” and a recei
ver “Bob”) to communicate with perfect security, even if the (measurement) hardw
are they are using has been tampered with (e.g.,
by an eavesdropper) and thus is not trus
ted. It is achieved by measuring correlations between signals from Alice and Bob
rather than the actual signals themselves.
</t>
<t> QKD protocols based on Continuous Variable (
CV-QKD) have recently seen plenty of interest as they only require telecommunica
tions equipment that is readily available and
is also in common use industry-wide. This ki
nd of technology is a potentially high-performance technique for secure key dist
ribution over limited distances.
The recent demonstration of CV-QKD shows
compatibility with classical coherent detection schemes that are widely used fo
r high bandwidth classical
communication systems <xref target="Gros
shans" />. Note that we still do not have a quantum repeater for the continuous
variable systems; hence, this kind of QKD technologies
can be used for the short distance commu
nications or trusted relay-based QKD networks.
</t>
<t> Secret sharing can be used to distribute a s
ecret key among multiple nodes by letting each node know a share or a part of th
e secret key, while no single node can know the
entire secret key. The secret key can only b
e re-constructed via collaboration from a sufficient number of nodes. Quantum Se
cret Sharing (QSS) typically refers to the
scenario: The secret key to be shared is
based on quantum states instead of classical bits. QSS enables to split and sha
re such quantum states among multiple nodes.
</t>
<t> There are some entanglement-based QKD protoc
ols, such as <xref target="Treiber"/><xref target="E91"/><xref target="BBM92"/>,
which work differently than the above steps. The entanglement-based schemes, wh
ere entangled states are
prepared externally to the quantum node A an
d the quantum node B, are not normally considered "prepare-and-measure" as defin
ed in <xref target="Wehner"/>;
other entanglement-based schemes, where
entanglement is
generated within the source quantum node
can still be considered "prepare-and-measure"; send-and-return schemes can stil
l be "prepare-and-measure", if the information content, from which keys will be
derived, is prepared within the quantum
node A before being sent to the quantum node B for measurement.
</t>
</list>
</t>
<t> As a result, the Quantum Internet in <xref target="fi
g:securecom" /> contains quantum channels. And in order to support secure commun
ication setup especially in large-scale deployment, it also requires entanglemen
t generation
and entanglement distribution <xref target="I-D.van-meter
-qirg-quantum-connection-setup"/>, quantum repeaters/routers, and/or trusted QKD
relays.
</t>
<t> <li>Secret sharing can be used to distribute a secret key among
<?rfc needLines="16" ?> multiple nodes by letting each node know a share or a part of the
<figure anchor="fig:securecom" title="Secure Comm secret key, while no single node can know the entire secret key. The
unication Setup"> secret key can only be reconstructed via collaboration from a
<artwork align="center"> sufficient number of nodes. Quantum Secret Sharing (QSS) typically
<![CDATA[ refers to the following scenario: the secret key to be shared is based
on quantum states instead of classical bits. QSS enables splitting and
sharing such quantum states among multiple nodes.</li>
<li>There are some entanglement-based QKD protocols, such as that describ
ed in <xref
target="Treiber" format="default"/>, <xref target="E91"
format="default"/>, and <xref target="BBM92" format="default"/>, which
work differently than the above steps. The entanglement-based schemes,
where entangled states are prepared externally to the quantum node A
and the quantum node B, are not normally considered
"prepare and measure" as defined in <xref target="Wehner"
format="default"/>. Other entanglement-based schemes, where
entanglement is generated within the source quantum node, can still be
considered "prepare and measure". Send-and-return schemes can still be
"prepare and measure" if the information content, from which keys
will be derived, is prepared within the quantum node A before being
sent to the quantum node B for measurement.</li>
</ol>
<t> As a result, the Quantum Internet in <xref target="fig_securecom"
format="default"/> contains quantum channels. And in order to support
secure communication setup, especially in large-scale deployment, it
also requires entanglement generation and entanglement distribution
<xref target="I-D.van-meter-qirg-quantum-connection-setup"
format="default"/>, quantum repeaters/routers, and/or trusted QKD
relays.
</t>
<figure anchor="fig_securecom">
<name>Secure Communication Setup</name>
<artwork align="center" name="" type="" alt=""><![CDATA[
+---------------+ +---------------+
| End User | | End User |
+---------------+ +---------------+
^ ^
| Local Secure Interface | Local Secure Interface
| (e.g., the same physical hardware | (e.g., the same physical hardware
| or a local secure network) | or a local secure network)
V V
+-----------------+ /--------\ +-----------------+ +-----------------+ /--------\ +-----------------+
| |--->( Quantum )--->| | | |--->( Quantum )--->| |
| | ( Internet ) | | | | ( Internet ) | |
| Quantum | \--------/ | Quantum | | Quantum | \--------/ | Quantum |
| Node A | | Node B | | Node A | | Node B |
| | /--------\ | | | | /--------\ | |
| | ( Classical) | | | | ( Classical) | |
| |<-->( Internet )<-->| | | |<-->( Internet )<-->| |
+-----------------+ \--------/ +-----------------+ +-----------------+ \--------/ +-----------------+
]]> ]]></artwork>
</artwork> </figure>
</figure> </section>
</t> <section anchor="sec_usecase2" numbered="true" toc="default">
<name>Blind Quantum Computing</name>
</section> <t>Blind quantum computing refers to the following scenario:
</t>
<ol spacing="normal" type="1">
<li>A client node with source data delegates the computation of the
source data to a remote computation node (i.e., a server).</li>
<section anchor="sec:usecase2" title="Blind Quantum Computing"> <li>Furthermore, the client node does not want to disclose any
<t> source data to the remote computation node, which preserves the
Blind quantum computing refers to the following s source data privacy.</li>
cenario:
<list style="numbers">
<t>A client node with source data delegat
es the computation of the source data to a remote computation node (i.e. a serve
r).</t>
<t>Furthermore, the client node does not
want to disclose any source data to the remote computation node, which preserves
the source data privacy.</t>
<t>Note that there is no assumption or gu
arantee that the remote computation node is a trusted entity from the source dat
a privacy perspective.</t>
</list>
</t>
<t> As an example illustrated in <xref target="fig:bqcom" <li>Note that there is no assumption or guarantee that the remote
/>, a terminal node can be a small quantum computer with limited computation ca computation node is a trusted entity from the source data privacy
pability compared to perspective.</li>
a remote quantum computation node (e.g., a remote mainfra </ol>
me quantum computer), but the terminal node needs to run a computation-intensive <t> As an example illustrated in <xref target="fig_bqcom"
task format="default"/>, a terminal node can be a small quantum computer
(e.g., Shor’s factoring algorithm). The terminal node can with limited computation capability compared to a remote quantum
create individual qubits and send them to the remote quantum computation node. computation node (e.g., a remote mainframe quantum computer), but the
Then, the remote terminal node needs to run a computation-intensive task (e.g., Shor's
quantum computation node can entangle the qubits, calcula factoring algorithm). The terminal node can create individual qubits
te on them, measure them, generate measurement results in classical bits, and re and send them to the remote quantum computation node. Then, the remote
turn the measurement quantum computation node can entangle the qubits, calculate on them,
results to the terminal node. It is noted that those meas measure them, generate measurement results in classical bits, and
urement results will look like purely random data to the remote quantum computat return the measurement results to the terminal node. It is noted that
ion node because those measurement results will look like purely random data to the
the initial states of the qubits were chosen in a cryptog remote quantum computation node because the initial states of the
raphically secure fashion. qubits were chosen in a cryptographically secure fashion.
</t> </t>
<!--<t> <!--<t> As an example illustrated in <xref target="fig:bqcom" />, a
As an example illustrated in <xref target="fig:bq terminal node such as a home gateway has collected lots of data
com" />, a terminal node such as a home gateway has collected lots of data and n and needs to perform computation on the data. The terminal node
eeds could be a classical node without any quantum capability, a
to perform computation on the data. The terminal bare-bone quantum end-node or a full-fledged quantum
node could be a classical node without any quantum capability, a bare-bone computer. The terminal node has insufficient computing power and
quantum end-node or a full-fledged quantum comput needs to offload data computation to some remote nodes. Although
er. The terminal node has insufficient computing power and needs to offload data the terminal node can upload the data to the cloud to leverage
computation to some remote nodes. Although the te cloud computing without introducing local computing overhead, to
rminal node can upload the data to the cloud to leverage cloud computing without upload the data to the cloud can cause privacy concerns. In this
introducing local computing overhead, to upload t particular case, there is no privacy concern since the source
he data to the cloud can cause privacy concerns. data will not be sent to the remote computation node which could
In this particular case, there is no privacy conc be compromised. Many protocols as described in <xref
ern since the source data will not be sent target="Fitzsimons" /> for delegated quantum computing or Blind
to the remote computation node which could be com Quantum Computation (BQC) can be leveraged to realize secure
promised. Many protocols as described in <xref target="Fitzsimons" /> for delega delegated computation and guarantee privacy preservation
ted quantum simultaneously. </t>
computing or Blind Quantum Computation (BQC) can
be leveraged to realize secure delegated computation and guarantee
privacy preservation simultaneously.
</t>
--> -->
<t> <t>As a new client/server computation model, Blind Quantum Computation
As a new client/server computation model, Blind Q (BQC) generally enables the following process:</t>
uantum Computation (BQC) generally enables: 1) The client delegates a computatio <ol spacing="normal" type="1">
n <li>The client delegates a computation function to the server.</li>
function to the server; 2) The client does not se <li>The client does not send original qubits to
nd original qubits to the server, but send transformed qubits to the server; 3) the server but does send transformed qubits to the server.</li>
The computation <li>The computation function is performed at the server on the
function is performed at the server on the transf transformed qubits to generate temporary result qubits, which could be
ormed qubits to generate temporary result qubits, which could be quantum-circuit quantum-circuit-based computation or measurement-based quantum
-based computation. The server sends the temporary result qubits to the
computation or measurement-based quantum computat client.</li>
ion. The server sends the temporary result qubits to the client; 4) The client r <li>The client receives the temporary result qubits and transforms
eceives the them to the final result qubits.</li>
temporary result qubits and transforms them to th </ol>
e final result qubits. During this process, the server can not figure out the or <t>During this process, the
iginal qubits from server cannot figure out the original qubits from the transformed
the transformed qubits. Also, it will not take to qubits. Also, it will not take too much effort on the client side to
o much efforts on the client side to transform the original qubits to the transf transform the original qubits to the transformed qubits or transform
ormed qubits, or transform the temporary result qubits to the final result qubits. One of the
the temporary result qubits to the final result q very first BQC protocols, such as that described in <xref target="Childs"
ubits. One of the very first BQC protocols such as <xref target="Childs"/> follo format="default"/>, follows this process, although the client needs
ws this process, although the client needs some some basic quantum features such as quantum memory, qubit preparation
basic quantum features such as quantum memory, qu and measurement, and qubit transmission. Measurement-based quantum
bit preparation and measurement, and qubit transmission. Measurement-based quant computation is out of the scope of this document, and more details
um computation is about it can be found in <xref target="Jozsa2005" format="default"/>.
out of the scope of this document and more detail </t>
s about it can be found in <xref target="Jozsa2005"/>. <t>It is worth noting that:
</t> </t>
<ol spacing="normal" type="1">
<li>The BQC protocol in <xref target="Childs" format="default"/> is
a circuit-based BQC model, where the client only performs simple
quantum circuit for qubit transformation, while the server performs
a sequence of quantum logic gates. Qubits are transmitted back and
forth between the client and the server.</li>
<t> <li>Universal BQC (UBQC) in <xref target="Broadbent"
It is worth noting that: format="default"/> is a measurement-based BQC model, which is based
<list style="numbers"> on measurement-based quantum computing leveraging entangled
<t> The BQC protocol in <xref target="Chi states. The principle in UBQC is based on the fact that the quantum
lds"/> is a circuit-based BQC model, where the client only performs simple quant teleportation plus a rotated Bell measurement realize a quantum
um circuit for computation, which can be repeated multiple times to realize a
qubit transformation, while the s sequence of quantum computation. In this approach, the client first
erver performs a sequence of quantum logic gates. Qubits are transmitted back an prepares transformed qubits and sends them to the server, and the
d forth between the client server needs to first prepare entangled states from all received
and the server. qubits. Then, multiple interaction and measurement rounds happen
</t> between the client and the server.
<t> Universal BQC in <xref target="Broadb
ent"/> is a measurement-based BQC model, which is based on measurement-based qua
ntum computing leveraging
entangled states. The principle i
n UBQC is based on the fact the quantum teleportation plus a rotated Bell measur
ement realizes a quantum computation,
which can be repeated multiple ti
mes to realize a sequence of quantum computation. In this approach, the client f
irst prepares transformed qubits
and sends them to the server and
the server needs first to prepare entangled states from all received qubits. The
n, multiple interaction and measurement
rounds happen between the client
and the server. For each round, the client computes and sends new measurement in
structions or measurement adaptations
to the server; then, the server p
erforms the measurement according to the received measurement instructions to ge
nerate measurement results (qubits or in classic bits);
the client receives the measureme
nt results and transforms them to the final results.
</t>
<t> A hybrid universal BQC is proposed in
<xref target="Zhang2009"/>, where the server performs both quantum circuits lik
e <xref target="Childs"/> and quantum
measurements like <xref target="B
roadbent"/> to reduce the number of required entangled states in <xref target="B
roadbent"/>. Also, the client is much simpler than
the client in <xref target="Child
s"/>. This hybrid BQC is a combination of circuit-based BQC model and measuremen
t-based BQC model.
</t>
<t> It will be ideal if the client in BQC
is a purely classical client, which only needs to interact with the server usin
g classical channel and communications.
<xref target="Huang"/> demonstrat
es such an approach, where a classical client leverages two entangled servers to
perform BQC, with the assumption that
both servers cannot communicate w
ith each other; otherwise, the blindness or privacy of the client cannot be guar
anteed. The scenario as demonstrated
in <xref target="Huang"/> is esse
ntially an example of BQC with multiple servers.
</t>
<t> How to verify that the server will pe
rform what the client requests or expects is an important issue in many BQC prot
ocols, referred to as verifiable BQC.
<xref target="Fitzsimons"/> discu
sses this issue and compares it in various BQC protocols.
</t>
</list> <!--[rfced] For easier readability, may we make this an ordered list?
</t>
<t> In <xref target="fig:bqcom" />, the Quantum Internet Original:
contains quantum channels and quantum repeaters/routers for long-distance qubits For each round, the client computes and sends new measurement
transmission instructions or measurement adaptations to the server; then, the
<xref target="RFC9340" />.</t> server performs the measurement according to the received
measurement instructions to generate measurement results (qubits
or in classic bits); the client receives the measurement results
and transforms them to the final results.
<t> Perhaps:
<?rfc needLines="16" ?> For each round:
<figure anchor="fig:bqcom" title="Bind Quantum Co
mputing"> i. the client computes and sends new measurement instructions
<artwork align="center"> or measurement adaptations to the server;
<![CDATA[
ii. the server performs the measurement according to the
received measurement instructions to generate measurement
results (in qubits or classic bits); and
iii. the client receives the measurement results and
transforms them to the final results.
-->
For each round, the client
computes and sends new measurement instructions or measurement
adaptations to the server; the server performs the measurement
according to the received measurement instructions to generate
measurement results (in qubits or classic bits); and then the client re
ceives
the measurement results and transforms them to the final
results.</li>
<li>A hybrid UBQC is proposed in <xref target="Zhang2009"
format="default"/>, where the server performs both quantum circuits
like that demonstrated in <xref target="Childs" format="default"/>
and quantum measurements like that demonstrated in <xref
target="Broadbent" format="default"/> to reduce the number of
required entangled states in <xref target="Broadbent"
format="default"/>. Also, the client is much simpler than the client
in <xref target="Childs" format="default"/>. This hybrid BQC is a
combination of a circuit-based BQC model and a measurement-based BQC
model.</li>
<li>It is ideal if the client in BQC is a purely classical
client, which only needs to interact with the server using classical
channels and communications. <xref target="Huang" format="default"/>
demonstrates such an approach where a classical client leverages
two entangled servers to perform BQC with the assumption that both
servers cannot communicate with each other; otherwise, the blindness
or privacy of the client cannot be guaranteed. The scenario as
demonstrated in <xref target="Huang" format="default"/> is
essentially an example of BQC with multiple servers.</li>
<li>How to verify that the server will perform what the client
requests or expects is an important issue in many BQC protocols,
referred to as "verifiable BQC". <xref target="Fitzsimons"
format="default"/> discusses this issue and compares it in various
BQC protocols.</li>
</ol>
<t> In <xref target="fig_bqcom" format="default"/>, the Quantum Internet
contains quantum channels and quantum repeaters/routers for long-distance qubit
s transmission <xref target="RFC9340" format="default"/>.</t>
<figure anchor="fig_bqcom">
<name>Bind Quantum Computing</name>
<artwork align="center" name="" type="" alt=""><![CDATA[
+----------------+ /--------\ +-------------------+ +----------------+ /--------\ +-------------------+
| |--->( Quantum )--->| | | |--->( Quantum )--->| |
| | ( Internet ) | Remote Quantum | | | ( Internet ) | Remote Quantum |
| Terminal | \--------/ | Computation | | Terminal | \--------/ | Computation |
| Node | | Node | | Node | | Node |
| (e.g., A Small| /--------\ | (e.g., Remote | | (e.g., a small| /--------\ | (e.g., a remote |
| Quantum | ( Classical) | Mainframe | | quantum | ( Classical) | mainframe |
| Computer) |<-->( Internet )<-->| Quantum Computer)| | computer) |<-->( Internet )<-->| quantum computer) |
+----------------+ \--------/ +-------------------+ +----------------+ \--------/ +-------------------+
]]> ]]></artwork>
</artwork> </figure>
</figure> </section>
</t> <section anchor="sec_usecase3" numbered="true" toc="default">
<name>Distributed Quantum Computing</name>
</section> <t>There can be two types of distributed quantum computing <xref target=
"Denchev" format="default"/>:
<section anchor="sec:usecase3" title="Distributed Quantum Computi </t>
ng"> <ol spacing="normal" type="1">
<li>Leverage quantum mechanics to enhance classical distributed
computing. For example, entangled quantum states can be exploited to
improve leader election in classical distributed computing by
simply measuring the entangled quantum states at each party (e.g., a
node or a device) without introducing any classical communications
among distributed parties <xref target="Pal"
format="default"/>. Normally, pre-shared entanglement first needs to be
established among distributed parties, followed by LOCC operations
at each party. And it generally does not need to transfer qubits
among distributed parties.</li>
<li><t>Distribute quantum computing functions to distributed quantum
computers. A quantum computing task or function (e.g., quantum
gates) is split and distributed to multiple physically separate
quantum computers. And it may or may not need to transmit qubits
(either inputs or outputs) among those distributed quantum
computers. Entangled states will be needed and actually consumed to
support such distributed quantum computing tasks. It is worth noting
that:</t>
<ol type="a" spacing="normal">
<li>Entangled states can be created beforehand and stored or
buffered;</li>
<li>The rate of entanglement creation will limit the
performance of practical Quantum Internet applications including
distributed quantum computing, although entangled states could be
buffered.</li></ol>
<t>There can be two types of distributed quantum computin <!-- [rfced] May we expand "CNOT" as "Controlled NOT"? Also, may we update
g <xref target="Denchev" />: "have provided" to "have demonstrated" or "have shown", which is used more
<list style="numbers"> frequently in RFCs?
<t>Leverage quantum mechanics to enhance
classical distributed computing. For example, entangled quantum states can be
exploited to improve leader election in c
lassical distributed computing, by simply measuring the entangled quantum states
at each
party (e.g., a node or a device) without
introducing any classical communications among distributed parties <xref target=
"Pal" />. Normally, pre-shared entanglement needs first be
established among distributed parties, fo
llowed by LOCC operations at each party. And it generally does not need to trans
fer qubits
among distributed parties.
</t>
<t>Distribute quantum computing functions
to distributed quantum computers. A quantum computing task or function (e.g., q
uantum
gates) is split and distributed to multip
le physically separate quantum computers. And it may or may not need to transmit
qubits (either inputs or outputs) among t
hose distributed quantum computers. Entangled states will be needed and actually
consumed to support
such distributed quantum computing tasks.
It is worth noting that: 1)Entangled states can be created beforehand and store
d or buffered; 2)
The rate of entanglement creation will li
mit the performance of practical quantum internet applicaitons including distrib
uted quantum computing,
although entangled states could be buffer
ed. For example, <xref target="Gottesman1999" /> and <xref target="Eisert" /> ha
ve proved that a CNOT gate can be
realized jointly by and distributed to mu
ltiple quantum computers. The rest of this section focuses on this type of distr
ibuted quantum computing.
</t>
</list>
</t>
<t> Current:
As a scenario for the second type of distributed quantum For example, [Gottesman1999] and [Eisert] have proved that a CNOT
computing, Noisy Intermediate-Scale Quantum (NISQ) computers distributed in gate can be realized jointly by and distributed to multiple
different locations are available for sharing. According quantum computers.
to the definition in <xref target="Preskill" />, a NISQ computer -->
can only realize a small number of qubits and has limited
quantum error correction.
This scenario is referred to as distributed quantum
computing <xref target="Caleffi"/> <xref target="Cacciapu
oti2020"/> <xref target="Cacciapuoti2019"/>. This application scenario reflects
the vastly increased computing power which quantum comput
ers as a part of the Quantum Internet can bring, in contrast to classical
computers in the Classical Internet, in the context of di
stributed quantum computing ecosystem <xref target="Cuomo"/>. According to
<xref target="Cuomo"/>, quantum teleportation enables a n
ew communication paradigm, referred to as teledata <xref target="VanMeter2006-01
"/>, which moves quantum states
among qubits to distributed quantum computers. In additio
n, distributed quantum computation also needs the capability of remotely perform
ing
quantum computation on qubits on distributed quantum comp
uters, which can be enabled by the technique called telegate <xref target="VanMe
ter2006-02"/>.
</t>
<t>As an example, a user can leverage these connected NIS <t>For example, <xref target="Gottesman1999"
Q computers to solve highly complex scientific computation format="default"/> and <xref target="Eisert" format="default"/> have
problems, such as analysis of chemical interactions for m proved that a CNOT gate can be realized jointly by and distributed
edical drug development <xref target="Cao"/> (see <xref target="fig:dqcom" />). to multiple quantum computers. The rest of this section focuses on
In this case, this type of distributed quantum computing.
qubits will be transmitted among connected quantum </t>
computers via quantum channels, while the user's executio </li>
n requests are transmitted to these quantum computers via classical channels </ol>
for coordination and control purpose. Another example of <t>As a scenario for the second type of distributed quantum computing,
distributed quantum computing is secure Multi-Party Quantum Computation (MPQC) < Noisy Intermediate-Scale Quantum (NISQ) computers distributed in
xref target="Crepeau"/>, different locations are available for sharing. According to the
which can be regarded as a quantum version of classical s definition in <xref target="Preskill" format="default"/>, a NISQ
ecure Multi-Party Computation (MPC). In a secure MPQC protocol, multiple partici computer can only realize a small number of qubits and has limited
pants jointly quantum error correction. This scenario is referred to as "distributed
perform quantum computation on a set of input quantum sta quantum computing" <xref target="Caleffi" format="default"/> <xref
tes, which are prepared and provided by different participants. One of the prima target="Cacciapuoti2020" format="default"/> <xref
ry aims of the secure target="Cacciapuoti2019" format="default"/>. This application scenario
MPQC is to guarantee that each participant will not know reflects the vastly increased computing power that quantum computers
input quantum states provided by other participants. Secure MPQC relies on verif can bring as a part of the Quantum Internet, in contrast to classical
iable computers in the Classical Internet, in the context of a distributed
quantum secret sharing <xref target="Lipinska" />. quantum computing ecosystem <xref target="Cuomo"
</t> format="default"/>. According to <xref target="Cuomo"
format="default"/>, quantum teleportation enables a new communication
paradigm, referred to as "teledata" <xref target="VanMeter2006-01"
format="default"/>, which moves quantum states among qubits to
distributed quantum computers. In addition, distributed quantum
computation also needs the capability of remotely performing quantum
computation on qubits on distributed quantum computers, which can be
enabled by the technique called "telegate" <xref
target="VanMeter2006-02" format="default"/>.
</t>
<t>As an example, a user can leverage these connected NISQ computers
to solve highly complex scientific computation problems, such as
analysis of chemical interactions for medical drug development <xref
target="Cao" format="default"/> (see <xref target="fig_dqcom"
format="default"/>). In this case, qubits will be transmitted among
connected quantum computers via quantum channels, while the user's
execution requests are transmitted to these quantum computers via
classical channels for coordination and control purpose. Another
example of distributed quantum computing is secure Multi-Party Quantum
Computation (MPQC) <xref target="Crepeau" format="default"/>, which
can be regarded as a quantum version of classical secure Multi-Party
Computation (MPC). In a secure MPQC protocol, multiple participants
jointly perform quantum computation on a set of input quantum states,
which are prepared and provided by different participants. One of the
primary aims of the secure MPQC is to guarantee that each participant
will not know input quantum states provided by other
participants. Secure MPQC relies on verifiable quantum secret sharing
<xref target="Lipinska" format="default"/>.
</t>
<t>For the example shown in <xref target="fig_dqcom"
format="default"/>, we want to move qubits from one NISQ computer to
another NISQ computer. For this purpose, quantum teleportation can be
leveraged to teleport sensitive data qubits from one quantum computer
(A) to another quantum computer (B). Note that <xref target="fig_dqcom"
format="default"/> does not cover measurement-based distributed
quantum computing, where quantum teleportation may not be required.
When quantum teleportation is employed, the following steps happen
between A and B. In fact, LOCC <xref target="Chitambar"
format="default"/> operations are conducted at the quantum computers A
and B in order to achieve quantum teleportation as illustrated in
<xref target="fig_dqcom" format="default"/>.
</t>
<ol spacing="normal" type="1">
<li>The quantum computer A locally generates some sensitive data
qubits to be teleported to the quantum computer B.</li>
<t> <li>A shared entanglement is established between the quantum
For the example shown in <xref target="fig:dqcom"/>, we w computer A and the quantum computer B (i.e., there are two entangled
ant to move qubits from one NISQ computer to another NISQ computer. For this pur qubits: q1 at A and q2 at B). For example, the quantum computer A
pose, quantum teleportation can be can generate two entangled qubits (i.e., q1 and q2) and send q2 to
leveraged to teleport sensitive data qubits from one quan the quantum computer B via quantum communications.</li>
tum computer A to another quantum computer B.
Note that <xref target="fig:dqcom" /> does not cover meas
urement-based distributed quantum computing, where quantum teleportation may not
be required.
When quantum teleportation is employed, the following ste
ps happen between A and B. In fact, LOCC <xref target="Chitambar"/> operations a
re conducted at the quantum
computers A and B in order to achieve quantum teleportati
on as illustrated in <xref target="fig:dqcom" />.
<list style="numbers">
<t> The quantum computer A locally genera
tes some sensitive data qubits to be teleported to the quantum computer B. </t>
<t> A shared entanglement is establis
hed between the quantum computer A and the quantum computer B (i.e., there are t
wo entangled qubits: q1 at A and q2 at B).
For example, the quantum computer
A can generate two entangled qubits (i.e., q1 and q2) and sends q2 to the quant
um computer B via quantum communications. </t>
<t> Then, the quantum computer A perf
orms a Bell measurement of the entangled qubit q1 and the sensitive data qubit.<
/t>
<t> The result from this Bell measure
ment will be encoded in two classical bits, which will be physically transmitted
via a classical channel to the quantum computer B.</t>
<t> Based on the received two classical b
its, the quantum computer B modifies the state of the entangled qubit q2 in the
way to generate a new qubit identical to
the sensitive data qubit at the quant
um computer A.</t>
</list>
</t>
<t> In <xref target="fig:dqcom" />, the Quantum Internet <li>Then, the quantum computer A performs a Bell measurement of the
contains quantum channels and quantum repeaters/routers <xref target="RFC9340" / entangled qubit q1 and the sensitive data qubit.</li>
>.
This application scenario needs to support entangleme
nt generation and entanglement distribution (or quantum connection)
setup <xref target="I-D.van-meter-qirg-quantum-co
nnection-setup"/> in order to support quantum teleportation.
</t>
<t> <li>The result from this Bell measurement will be encoded in two
<?rfc needLines="16" ?> classical bits, which will be physically transmitted via a classical
<figure anchor="fig:dqcom" title="Distributed Qua channel to the quantum computer B.</li>
ntum Computing">
<artwork align="center">
<![CDATA[
<li>Based on the received two classical bits, the quantum computer B
modifies the state of the entangled qubit q2 in the way to generate
a new qubit identical to the sensitive data qubit at the quantum
computer A.</li>
</ol>
<t>In <xref target="fig_dqcom" format="default"/>, the Quantum
Internet contains quantum channels and quantum repeaters/routers <xref
target="RFC9340" format="default"/>. This application scenario needs
to support entanglement generation and entanglement distribution (or
quantum connection) setup <xref
target="I-D.van-meter-qirg-quantum-connection-setup"
format="default"/> in order to support quantum teleportation.
</t>
<figure anchor="fig_dqcom">
<name>Distributed Quantum Computing</name>
<artwork align="center" name="" type="" alt=""><![CDATA[
+-----------------+ +-----------------+
| End User | | End User |
| | | |
+-----------------+ +-----------------+
^ ^
| Local Secure Interface | Local Secure Interface
| (e.g., the same phyical hardware | (e.g., the same physical hardware
| or a local secure network) | or a local secure network)
| |
+------------------+-------------------+ +------------------+-------------------+
| | | |
| | | |
V V V V
+----------------+ /--------\ +----------------+ +----------------+ /--------\ +----------------+
| |--->( Quantum )--->| | | |--->( Quantum )--->| |
| | ( Internet ) | | | | ( Internet ) | |
| Quantum | \--------/ | Quantum | | Quantum | \--------/ | Quantum |
| Computer A | | Computer B | | Computer A | | Computer B |
| (e.g., Site #1)| /--------\ | (e.g., Site #2)| | (e.g., Site #1)| /--------\ | (e.g., Site #2)|
| | ( Classical) | | | | ( Classical) | |
| |<-->( Internet )<-->| | | |<-->( Internet )<-->| |
+----------------+ \--------/ +----------------+ +----------------+ \--------/ +----------------+
]]> ]]></artwork>
</artwork> </figure>
</figure> </section>
</t>
</section>
</section> </section>
<section anchor="sec_generalrequirements" numbered="true" toc="default">
<name>General Requirements</name>
<t>Quantum technologies are steadily evolving and improving. Therefore,
it is hard to predict the timeline and future milestones of quantum
technologies as pointed out in <xref target="Grumbling"
format="default"/> for quantum computing. Currently, a NISQ computer can
achieve fifty to hundreds of qubits with some given error rate.
</t>
<t>On the network level, six stages of Quantum Internet development are
described in <xref target="Wehner" format="default"/> as a Quantum
Internet technology roadmap as follows:
</t>
<ol spacing="normal" type="1">
<li>Trusted repeater networks (Stage-1)</li>
<li>Prepare-and-measure networks (Stage-2)</li>
<li>Entanglement distribution networks (Stage-3)</li>
<li>Quantum memory networks (Stage-4)</li>
<li>Fault-tolerant few qubit networks (Stage-5)</li>
<li>Quantum computing networks (Stage-6)</li>
</ol>
<t>The first stage is simple trusted repeater networks, while the final
stage is the quantum computing networks where the full-blown Quantum
Internet will be achieved. Each intermediate stage brings with it new
functionality, new applications, and new characteristics. <xref
target="fig_appsinstages" format="default"/> illustrates Quantum
Internet application scenarios as described in Sections <xref
target="sec_applications" format="counter"/> and <xref
target="sec_usecases" format="counter"/> mapped to the Quantum Internet
stages described in <xref target="Wehner" format="default"/>. For
example, secure communication setup can be supported in Stage-1,
Stage-2, or Stage-3 but with different QKD solutions. More
specifically:</t>
<ul spacing="normal">
<li>In Stage-1, basic QKD is possible and can be leveraged to support
secure communication setup, but trusted nodes are required to provide
end-to-end security. The primary requirement is the trusted nodes. </li>
<li>In Stage-2, the end users can prepare and measure the qubits. In this
stage, the users can verify classical passwords without revealing
them.</li>
<li>In Stage-3, end-to-end security can be enabled based on quantum
repeaters and entanglement distribution to support the same secure
communication setup application. The primary requirement is entanglement
distribution to enable long-distance QKD. </li>
<li>In Stage-4, the quantum repeaters gain the capability of storing and
manipulating entangled qubits in the quantum memories. Using these kinds
of quantum networks, one can run sophisticated applications like blind
quantum computing, leader election, and quantum secret sharing. </li>
<li>In Stage-5, quantum repeaters can perform error correction; hence,
they can perform fault-tolerant quantum computations on the received
data. With the help of these repeaters, it is possible to run
distributed quantum computing and quantum sensor applications over a
smaller number of qubits.</li>
<li>Finally, in Stage-6, distributed quantum computing relying on more
qubits can be supported.</li>
</ul>
<section anchor="sec:generalrequirements" title="General Requirements"> <table align="center" anchor="fig_appsinstages">
<name>Example Application Scenarios in Different Quantum Internet Stages</name
<t>Quantum technologies are steadily evolving and improving. Ther >
efore, it is hard to predict the timeline and future milestones <thead>
of quantum technologies as pointed out in <xref target="Grumbling <tr>
"/> for quantum computing. Currently, a NISQ computer can achieve <th>Quantum Internet Stage</th>
fifty to hundreds of qubits with some given error rate. <th>Example Quantum Internet Use Cases</th>
</t> <th>Characteristic</th>
</tr>
<t>On the network level, six stages of Quantum Internet developme </thead>
nt are described in <xref target="Wehner"/> as Quantum Internet technology roadm <tbody>
ap as follows: <tr>
<list style="numbers"> <td>Stage-1</td>
<t>Trusted repeater networks (Stage-1)</t> <td>Secure communication setup using basic QKD</td>
<t>Prepare and measure networks (Stage-2)</t> <td>Trusted nodes</td>
<t>Entanglement distribution networks (Stage-3)</ </tr>
t> <tr>
<t>Quantum memory networks (Stage-4)</t> <td>Stage-2</td>
<t>Fault-tolerant few qubit networks (Stage-5)</t <td>Secure communication setup using the QKD with end-to-end security</td>
> <td>Prepare-and-measure capability</td>
<t>Quantum computing networks (Stage-6)</t> </tr>
</list> <tr>
</t> <td>Stage-3</td>
<td>Secure communication setup using entanglement-enabled QKD</td>
<t>The first stage is simple trusted repeater networks, while the <td>Entanglement distribution</td>
final stage is the quantum computing networks where the full-blown </tr>
Quantum Internet will be achieved. Each intermediate stage brings <tr>
with it new functionality, new applications, <td>Stage-4</td>
and new characteristics. <xref target="fig:appsinstages"/> illus <td>Blind quantum computing</td>
trates Quantum Internet application scenarios as described in <xref target="sec: <td>Quantum memory</td>
applications" /> and <xref target="sec:usecases" /> mapped to </tr>
the Quantum Internet stages described in <xref target="Wehner"/>. <tr>
For example, secure communication setup can be supported in <td>Stage-5</td>
Stage-1, Stage-2, or Stage-3, but with different QKD solutions. <td>Higher-accuracy clock synchronization</td>
More specifically:</t> <td>Fault tolerance</td>
</tr>
<t>In Stage-1, basic QKD is possible and can be leveraged to supp <tr>
ort secure communication setup but trusted nodes are <td>Stage-6</td>
required to provide end-to-end security. The primary requirement <td>Distributed quantum computing</td>
is the trusted nodes. </t> <td>More qubits</td>
</tr>
<t>In Stage-2, the end users can prepare and measure the qubits. </tbody>
In this stage, the users can verify classical passwords without revealing it.</t </table>
> <t>Some general and functional requirements on the Quantum Internet from
the networking perspective, based on the above application scenarios and
<t>In Stage-3, end-to-end security can be enabled based on quantu Quantum Internet technology roadmap <xref target="Wehner"
m repeaters and entanglement distribution, to support the format="default"/>, are identified and described in next sections. </t>
same secure communication setup application. The primary requirem <section anchor="sec_requirement01" numbered="true" toc="default">
ent is entanglement distribution to enable long-distance QKD. </t> <name>Operations on Entangled Qubits</name>
<t>Methods for facilitating quantum applications to interact
<t>In Stage-4, the quantum repeaters gain the capability of stori efficiently with entangled qubits are necessary in order for them to
ng and manipulating entangled qubits in the quantum memories. Using these kind o trigger distribution of designated entangled qubits to potentially any
f quantum networks, other quantum node residing in the Quantum Internet. To accomplish
one can run sophisticated applications like blind quantum computi this, specific operations must be performed on entangled qubits (e.g.,
ng, leader election, quantum secret sharing. </t> entanglement swapping or entanglement distillation). Quantum nodes may
be quantum end nodes, quantum repeaters/routers, and/or quantum
<t>In Stage-5, quantum repeaters can perform error correction; he computers.</t>
nce they can perform fault-tolerant quantum computations on the received data. W </section>
ith the help of <section anchor="sec_requirement02" numbered="true" toc="default">
these repeaters, it is possible to run distributed quantum comput <name>Entanglement Distribution</name>
ing and quantum sensor applications over a smaller number of qubits.</t> <t>Quantum repeaters/routers should support robust and efficient
entanglement distribution in order to extend and establish
<t>Finally, in Stage-6, distributed quantum computing relying on a high-fidelity entanglement connection between two quantum nodes. For
more qubits can be supported.</t> achieving this, it is required to first generate an entangled pair on
each hop of the path between these two nodes and then perform
<t> entanglement-swapping operations at each of the intermediate
<?rfc needLines="16" ?> nodes. </t>
<figure anchor="fig:appsinstages" title="Example </section>
Application Scenarios in Different Quantum Internet Stages"> <section anchor="sec_requirement03" numbered="true" toc="default">
<artwork align="center"> <name>The Need for Classical Channels</name>
<![CDATA[ <t>Quantum end nodes must send additional information on classical
+---------+----------------------------+------------------------+ channels to aid in transferring and understanding qubits across
| Quantum | Example Quantum | | quantum repeaters/receivers. Examples of such additional information
| Internet| Internet Use | Characteristic | include qubit measurements in secure communication setup (<xref
| Stage | Cases | | target="sec_usecase1" format="default"/>) and Bell measurements in
+---------+----------------------------+------------------------+ distributed quantum computing (<xref target="sec_usecase3"
| Stage-1 | Secure comm setup | Trusted nodes | format="default"/>). In addition, qubits are transferred individually
| | using basic QKD | | and do not have any associated packet header, which can help in
|---------------------------------------------------------------| transferring the qubit. Any extra information to aid in routing,
| Stage-2 | Secure comm setup | Prepare-and-measure | identification, etc. of the qubit(s) must be sent via classical
| | using the QKD with | capability | channels.</t>
| | end-to-end security | | </section>
|---------------------------------------------------------------| <section anchor="sec_requirement04" numbered="true" toc="default">
| Stage-3 | Secure comm setup | Entanglement | <name>Quantum Internet Management</name>
| | using entanglement-enabled | distribution | <t>Methods for managing and controlling the Quantum Internet including
| | QKD | | quantum nodes and their quantum resources are necessary. The
|---------------------------------------------------------------| resources of a quantum node may include quantum memory, quantum
| Stage-4 | Blind quantum | Quantum memory | channels, qubits, established quantum connections, etc. Such
| | computing | | management methods can be used to monitor the network status of the
|---------------------------------------------------------------| Quantum Internet, diagnose and identify potential issues (e.g., quantum
| Stage-5 | Higher-Accuracy Clock | Fault tolerance | connections), and configure quantum nodes with new actions and/or
| | synchronization | | policies (e.g., to perform a new entanglement-swapping operation). A new
|---------------------------------------------------------------| management information model for the Quantum Internet may need to be
| Stage-6 | Distributed quantum | More qubits | developed. </t>
| | computing | | </section>
+---------------------------------------------------------------+
]]>
</artwork>
</figure>
</t>
<t>Some general and functional requirements on the Quantum Intern
et from the networking perspective, based on the above
application scenarios and Quantum Internet technology roadmap <xr
ef target="Wehner"/>, are identified and described in next sections. </t>
<section anchor="sec:requirement01" title="Operations on Entangled Qubits"
>
<t> Methods for facilitating quantum applications to interact eff
iciently with entangled qubits are necessary in
order for them to trigger distribution of designated entangled qu
bits to potentially any other quantum node residing
in the Quantum Internet. To accomplish this, specific operations
must be performed on entangled qubits
(e.g., entanglement swapping, entanglement distillation). Quantu
m nodes may be quantum end nodes,
quantum repeaters/routers, and/or quantum computers.</t>
</section>
<section anchor="sec:requirement02" title="Entanglement Distribution">
<t> Quantum repeaters/routers should support robust and efficient
entanglement distribution in order to extend and establish
high-fidelity entanglement connection between two quantum nodes.
For achieving this, it is required to first generate an entangled pair on
each hop of the path between these two nodes, and then perform en
tanglement swapping operations at each of the intermediate nodes. </t>
</section>
<section anchor="sec:requirement03" title="The Need for Classical Chann
els">
<t> Quantum end nodes must send additional information on classic
al channels to aid in transferring and understanding qubits across
quantum repeaters/receivers. Examples of such additional informat
ion include qubit measurements in secure communication setup <xref target="sec:u
secase1"/>,
and Bell measurements in distributed quantum computing <xref targ
et="sec:usecase3"/>. In addition, qubits are transferred individually and do not
have any associated packet header
which can help in transferring the qubit. Any extra information t
o aid in routing, identification, etc., of the qubit(s)
must be sent via classical channels.</t>
</section>
<section anchor="sec:requirement04" title="Quantum Internet Management"
>
<t> Methods for managing and controlling the Quantum Internet inc
luding quantum nodes and their quantum resources are necessary.
The resources of a quantum node may include quantum memory, quant
um channels, qubits, established quantum connections, etc. Such
management methods can be used to monitor network status of the Q
uantum Internet, diagnose and identify potential issues
(e.g. quantum connections), and configure quantum nodes with new
actions and/or policies (e.g. to perform a new entanglement
swapping operation). New management information model for the Qua
ntum Internet may need to be developed. </t>
</section>
</section>
<section anchor="sec:conclusion" title="Conclusion">
<t>
This document provides an overview of some expected application categor
ies for the Quantum Internet, and then details selected application scenarios.
The applications are first grouped by their usage which is easy to unde
rstand classification scheme.
This set of applications may, of course, expand over time as the Quantu
m Internet matures. Finally, some
general requirements for the Quantum Internet are also provided.
</t>
<t>
This document can also serve as an introductory text to readers interes
ted in learning about the practical uses
of the Quantum Internet. Finally, it is hoped that this document will
help guide further research and development
of the Quantum Internet functionality required to implement the applica
tion scenarios described herein.
</t>
</section> </section>
<section anchor="sec_conclusion" numbered="true" toc="default">
<section anchor="IANA" title="IANA Considerations"> <name>Conclusion</name>
<t>This document provides an overview of some expected application
<t>This document requests no IANA actions. categories for the Quantum Internet and then details selected
application scenarios. The applications are first grouped by their
usage, which is an easy-to-understand classification scheme. This set of
applications may, of course, expand over time as the Quantum Internet
matures. Finally, some general requirements for the Quantum Internet are
also provided.
</t>
<t>This document can also serve as an introductory text to readers
interested in learning about the practical uses of the Quantum Internet.
Finally, it is hoped that this document will help guide further research
and development of the Quantum Internet functionality required to
implement the application scenarios described herein.
</t>
</section>
<section anchor="IANA" numbered="true" toc="default">
<name>IANA Considerations</name>
<t>This document has no IANA actions.</t>
</section>
<section anchor="sec_security" numbered="true" toc="default">
<name>Security Considerations</name>
<t>This document does not define an architecture nor a specific protocol
for the Quantum Internet. It focuses instead on detailing application
scenarios and requirements and describing typical Quantum Internet
applications. However, some salient observations can be made regarding
security of the Quantum Internet as follows.
</t>
<t>It has been identified in <xref target="NISTIR8240"
format="default"/> that, once large-scale quantum computing becomes
reality, it will be able to break many of the public key (i.e.,
asymmetric) cryptosystems currently in use. This is because of the
increase in computing ability with quantum computers for certain classes
of problems (e.g., prime factorization and optimizations). This would
negatively affect many of the security mechanisms currently in use on
the Classical Internet that are based on public key (Diffie-Hellman)
encryption. This has given strong impetus for starting development of
new cryptographic systems that are secure against quantum computing
attacks <xref target="NISTIR8240" format="default"/>.
</t>
<t>Interestingly, development of the Quantum Internet will also mitigate
the threats posed by quantum computing attacks against Diffie-Hellman
based public key cryptosystems. Specifically, the secure communication
setup feature of the Quantum Internet, as described in <xref
target="sec_usecase1" format="default"/>, will be strongly resistant to
both classical and quantum computing attacks against Diffie-Hellman
based public key cryptosystems.
</t>
<t>A key additional threat consideration for the Quantum Internet is
addressed in <xref target="RFC7258" format="default"/>, which warns of
the dangers of pervasive monitoring as a widespread attack on privacy.
Pervasive monitoring is defined as a widespread, and usually covert,
surveillance through intrusive gathering of application content or
protocol metadata, such as headers. This can be accomplished through
active or passive wiretaps, through traffic analysis, or by subverting
the cryptographic keys used to secure communications.
</t>
<t>The secure communication setup feature of the Quantum Internet, as
described in <xref target="sec_usecase1" format="default"/>, will be
strongly resistant to pervasive monitoring based on directly attacking
(Diffie-Hellman) encryption keys. Also, <xref target="sec_usecase2"
format="default"/> describes a method to perform remote quantum
computing while preserving the privacy of the source data. Finally, the
intrinsic property of qubits to decohere if they are observed, albeit
covertly, will theoretically allow detection of unwanted monitoring in
some future solutions.
</t>
<t>Modern networks are implemented with zero trust principles where
classical cryptography is used for confidentiality, integrity
protection, and authentication on many of the logical layers of the
network stack, often all the way from device to software in the cloud
<xref target="NISTSP800-207" format="default"/>. The cryptographic
solutions in use today are based on well-understood primitives, provably
secure protocols, and state-of-the-art implementations that are secure
against a variety of side-channel attacks.
</t>
<t>In contrast to conventional cryptography and Post-Quantum
Cryptography (PQC), the security of QKD is inherently tied to the
physical layer, which makes the threat surfaces of QKD and conventional
cryptography quite different. QKD implementations have already been
subjected to publicized attacks <xref target="Zhao2008"
format="default"/>, and the National Security Agency (NSA) notes that the
risk profile of conventional cryptography is better understood <xref
target="NSA" format="default"/>. The fact that conventional cryptography
and PQC are implemented at a higher layer than the physical one means
PQC can be used to securely send protected information through untrusted
relays. This is in stark contrast with QKD, which relies on hop-by-hop
security between intermediate trusted nodes. The PQC approach is better
aligned with the modern technology environment, in which more
applications are moving toward end-to-end security and zero-trust
principles. It is also important to note that, while PQC can be deployed
as a software update, QKD requires new hardware. In addition, the IETF has
a
working group on Post-Quantum Use In Protocols (PQUIP) that is studying
PQC transition issues.
</t>
<t>Regarding QKD implementation details, the NSA states that
communication needs and security requirements physically conflict in QKD
and that the engineering required to balance them has extremely low
tolerance for error. While conventional cryptography can be implemented
in hardware in some cases for performance or other reasons, QKD is
inherently tied to hardware. The NSA points out that this makes QKD less
flexible with regard to upgrades or security patches. As QKD is
fundamentally a point-to-point protocol, the NSA also notes that QKD
networks often require the use of trusted relays, which increases the
security risk from insider threats.
</t>
<t>The UK's National Cyber Security Centre cautions against reliance on
QKD, especially in critical national infrastructure sectors, and
suggests that PQC, as standardized by NIST, is a better solution <xref
target="NCSC" format="default"/>. Meanwhile, the National Cybersecurity
Agency of France has decided that QKD could be considered as a
defense-in-depth measure complementing conventional cryptography, as
long as the cost incurred does not adversely affect the mitigation of
current threats to IT systems <xref target="ANNSI" format="default"/>.
</t> </t>
</section> </section>
<section anchor="sec:security" title="Security Considerations"> </middle>
<back>
<t> This document does not define an architecture nor a specific proto <!-- [rfced] References
col for the Quantum Internet. It focuses instead on
detailing application scenarios, requirements, and describing typical
Quantum Internet applications. However, some salient observations
can be made regarding security of the Quantum Internet as follows.
</t>
<t> a) The following references are not cited in the text. Please let
It has been identified in <xref target="NISTIR8240" /> that once large- us know where they should be cited or if these references should be deleted
scale quantum computing becomes from the Informative References section.
reality that it will be able to break many of the public-key (i.
e., asymmetric) cryptosystems
currently in use. This is because of the increase in computing
ability with quantum computers for certain classes
of problems (e.g., prime factorization, optimizations). This wo
uld negatively affect many of the security
mechanisms currently in use on the Classical Internet which are
based on public-key (Diffie-Hellman) encryption.
This has given strong impetus for starting development of new cr
yptographic systems that are secure against
quantum computing attacks <xref target="NISTIR8240" />.
</t>
<t> [Hill] Hill, R.M. and et. al., "A Tool for Functional Brain
Interestingly, development of the Quantum Internet will also mitigate t Imaging with Lifespan Compliance", Nature
he threats posed by quantum computing attacks against Communications 10, 4785(2019), 2019,
Diffie-Hellman based public-key cryptosystems. Specifically, the <https://doi.org/10.1038/s41467-019-12486-x>.
secure communication setup feature of the Quantum Internet as
described in <xref target="sec:usecase1" /> will be strongly res
istant to both classical and quantum computing attacks
against Diffie-Hellman based public-key cryptosystems.
</t>
<t>A key additional threat consideration for the Quantum Internet is poi [DAHLBERG-LL-QUANTUM]
nted to by <xref target="RFC7258" />, Dahlberg, A., Skrzypczyk, M., and S. Wehner, "The Link
which warns of the dangers of pervasive monitoring as a widesprea Layer service in a Quantum Internet", Work in Progress,
d attack on privacy. Pervasive monitoring Internet-Draft, draft-dahlberg-ll-quantum-03, 10 October
is defined as a widespread, and usually covert, surveillance thro 2019, <https://datatracker.ietf.org/doc/html/draft-
ugh intrusive gathering of application content dahlberg-ll-quantum-03>.
or protocol metadata such as headers. This can be accomplished t
hrough active or passive wiretaps, traffic
analysis, or subverting the cryptographic keys used to secure com
munications.
</t>
<t>The secure communication setup feature of the Quantum Internet as des [Wang] Wang, C., Deng, F-G., Li, Y-S., Liu, X-S., and G.L. Long,
cribed in <xref target="sec:usecase1" /> "Quantum Secure Direct Communication with High-Dimension
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attacking (Diffie-Hellman) encryption keys. Physical Society, 2005,
Also, <xref target="sec:usecase2" /> describes a method to perfor <https://doi.org/10.1103/PhysRevA.71.044305>.
m remote quantum computing while preserving the
privacy of the source data. Finally, the intrinsic property of qu
bits to decohere if they are observed, albeit
covertly, will theoretically allow detection of unwanted monitori
ng in some future solutions.
</t>
<t> Modern networks are implemented with zero trust principles where cla b) For the references below, the provided URLs and DOIs return different
ssical cryptography is used for confidentiality, integrity protection, documents than what is detailed in their reference entries. We have updated
and authentication on many of the logical layers of the network stac the references so that all the reference entry information corresponds
k, often all the way from device to software in the cloud <xref target="NISTSP80 accordingly. Please review and let us know if any further updates are
0-207"/>. needed for these references.
The cryptographic solutions in use today are based on well-under
stood primitives, provably secure protocols and state-of-the-art implementations
that are secure against a variety of side-channel attacks.
</t>
<t> In contrast to conventional cryptography and Post-Quantum Cryptography Original:
(PQC), the security of QKD is inherently tied to the physical layer, which makes [Eisert] Eisert, J. and et. al., "Optimal Local Implementation of
the threat Nonlocal Quantum Gates", Physical Review A, American
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mplementations have already been subjected to publicized attacks <xref target="Z <https://doi.org/10.1103/PhysRevA.101.032332>.
hao2008"/> and
the National Security Agency (NSA) notes that the
risk profile of conventional cryptography is better understood <
xref target="NSA"/>. The fact that conventional cryptography and PQC are impleme
nted at a higher layer than the physical one means
PQC can be used to securely send protected information through u
ntrusted relays. This is in stark contrast with QKD, which relies on hop-by-hop
security between
intermediate trusted nodes. The PQC approach is better aligned w
ith the modern technology environment, in which more applications are moving tow
ard end-to-end
security and zero-trust principles. It is also important to note
that while PQC can be deployed as a software update, QKD requires new hardware.
In addition,
IETF has a working group on Post-Quantum Use In Protocols (PQUIP
) that is studying PQC transition issues.
</t>
<t> Regarding QKD implementation details, the NSA states that communication Current:
needs and security requirements physically conflict in QKD and that the enginee [Eisert] Eisert, J., Jacobs, K., Papadopoulos, P., and M. B.
ring required to Plenio, "Optimal local implementation of nonlocal quantum
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other reasons, <https://doi.org/10.1103/PhysRevA.62.052317>.
QKD is inherently tied to hardware. The NSA points out that this ...
makes QKD less flexible with regard to upgrades or security patches. As QKD is Original:
fundamentally a [Lo] Lo, H.-K. and et. al., "Experimental Demonstration of
point-to-point protocol, the NSA also notes that QKD networks of Phase-Remapping Attack in a Practical Quantum Key
ten require the use of trusted relays, which increases the security risk from in Distribution System", Physical Review Letters, American
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<t> The UK’s National Cyber Security Centre cautions against reliance on QK Current:
D, especially in critical national infrastructure sectors, and suggests that PQC [Lo] Lo, H-K., Curty, M., and B. Qi, "Measurement-Device-
as standardized Independent Quantum Key Distribution", Physical Review
by the NIST is a better solution <xref target="NCSC"/>. Meanwhile, t Letters, American Physical Society,
he National Cybersecurity Agency of France has decided that QKD could be conside DOI 10.1103/PhysRevLett.108.130503, March 2012,
red as a defense-in-depth measure <https://doi.org/10.1103/PhysRevLett.108.130503>.
complementing conventional cryptography, as long as the cost inc ...
urred does not adversely affect the mitigation of current threats to IT systems Original:
<xref target="ANNSI"/>. [Taherkhani]
</t> Taherkhani, M.A., Navi, K., and R. Van Meter, "Resource-
Aware System Architecture Model for Implementation of
Quantum Aided Byzantine Agreement on Quantum Repeater
Networks", Quantum Science and Technology, IOP, 2017,
<https://dl.acm.org/doi/10.1145/1060590.1060662>.
</section> Current:
[Taherkhani]
Taherkhani, M. A., Navi, K., and R. Van Meter, "Resource-
aware System Architecture Model for Implementation of
Quantum aided Byzantine Agreement on Quantum Repeater
Networks", DOI 10.1088/2058-9565/aa9bb1, January 2017,
<https://arxiv.org/abs/1701.04588>.
...
Original:
[Treiber] Treiber, A. and et. al., "A Fully Automated Entanglement-
based Quantum Cryptography System for Telecom Fiber
Networks", New Journal of Physics, 11, 045013, 2009,
<https://doi.org/10.1364/OE.26.024260>.
<section anchor="Acknowledgments" title="Acknowledgments"> Current:
[Treiber] Treiber, A., Poppe, A., Hentschel, M., Ferrini, D.,
Lorünser, T., Querasser, E., Matyus, T., Hübel, H., and A.
Zeilinger, "A fully automated entanglement-based quantum
cryptography system for telecom fiber networks", New
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DOI 10.1088/1367-2630/11/4/045013, April 2009,
<https://iopscience.iop.org/
article/10.1088/1367-2630/11/4/045013>.
...
Original:
[Zhang2019]
Zhang, P. and et. al., "Integrated Relay Server for
Measurement-Device-Independent Quantum Key Distribution",
2019, <https://arxiv.org/abs/1912.09642>.
<t>The authors want to thank Michele Amoretti, Mathias Van Den Bossche, Xa Current:
vier de Foy, Patrick Gelard, Álvaro Gómez Iñesta, Mallory Knodel, Wojciech Kozlo [Zheng2019]
wski, Zheng, X., Zhang, P., Ge, R., Lu, L., He, G., Chen, Q.,
John Mattsson, Rodney Van Meter, Colin Perkins, Joey Salazar, and Josep Qu, F., Zhang, L., Cai, X., Lu, Y., Zhu, S., Wu, P., and
h Touch, Brian Trammell, and the rest of the QIRG community as a whole for their X-S. Ma, "Heterogeneously integrated, superconducting
very useful reviews silicon-photonic platform for measurement-device-
and comments to the document.</t> independent quantum key distribution",
DOI 10.1117/1.AP.3.5.055002, December 2019,
<https://arxiv.org/abs/1912.09642>.
</section> c) The URL for [BB84] leads to a 404 error. Additionally, the reference
appears to have been updated by a 2014 version. May we update the
reference entry as follows?
</middle> Original:
[BB84] Bennett, C. H. and G. Brassard, "Quantum Cryptography:
Public Key Distribution and Coin Tossing", 1984,
<http://researcher.watson.ibm.com/researcher/files/us-
bennetc/BB84highest.pdf>.
<back> Perhaps:
[BB84] Bennett, C. H. and G. Brassard, "Quantum cryptography:
Public key distribution and coin tossing",
DOI 10.1016/j.tcs.2014.05.025, December 2014,
<https://doi.org/10.1016/j.tcs.2014.05.025>.
-->
<references title="Informative References"> <displayreference target="I-D.dahlberg-ll-quantum" to="DAHLBERG-LL-QUANTUM"/>
<displayreference target="I-D.van-meter-qirg-quantum-connection-setup" to="QUANT
UM-CONNECTION"/>
&rfc7258; <references>
&rfc9340; <name>Informative References</name>
&I-D.dahlberg-ll-quantum; <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.725
&I-D.van-meter-qirg-quantum-connection-setup; 8.xml"/>
<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.934
0.xml"/>
<reference anchor="Castelvecchi" target="https://www.nature.com/articles/d <!-- [I-D.dahlberg-ll-quantum] Unused reference / IESG State: Expired
41586-018-01835-3"> Long way used to add editor role-->
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</author>
<author initials="M." surname="Skrzypczyk" fullname="Matthew Skrzypczyk">
<organization>QuTech, Delft University of Technology</organization>
</author>
<author initials="S." surname="Wehner" fullname="Stephanie Wehner" role="editor"
>
<organization>QuTech, Delft University of Technology</organization>
</author>
<date month="October" day="10" year="2019"/>
</front>
<seriesInfo name="Internet-Draft" value="draft-dahlberg-ll-quantum-03"/>
</reference>
<author initials="D." surname="Castelvecchi" /> <!-- [I-D.van-meter-qirg-quantum-connection-setup] IESG State: Expired -->
<xi:include href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.va
n-meter-qirg-quantum-connection-setup.xml"/>
<date year="2018" /> <reference anchor="Castelvecchi" target="https://www.nature.com/articles/d
</front> 41586-018-01835-3">
<seriesInfo name="Nature" value="554, 289-292" /> <front>
</reference> <title>The quantum internet has arrived (and it hasn't)</title>
<author initials="D." surname="Castelvecchi" fullname="Davide Castelve
cchi"/>
<date month="February" year="2018"/>
</front>
<seriesInfo name="DOI" value="10.1038/d41586-018-01835-3"/>
<refcontent>Nature 554, 289-292</refcontent>
</reference>
<reference anchor="Wehner" target="http://science.sciencemag.org/content/3 62/6412/eaam9288.full"> <reference anchor="Wehner" target="http://science.sciencemag.org/content/3 62/6412/eaam9288.full">
<front> <front>
<title>Quantum internet: A vision for the road ahead </title> <title>Quantum internet: A vision for the road ahead</title>
<author initials="S." surname="Wehner"> <author initials="S." surname="Wehner" fullname="Stephanie Wehner"/>
<organization></organization> <author initials="D." surname="Elkouss" fullname="David Elkouss"/>
</author> <author initials="R." surname="Hanson" fullname="Ronald Hanson"/>
<author initials="D." surname="Elkouss"> <date month="October" year="2018"/>
<organization></organization> </front>
</author> <seriesInfo name="DOI" value="10.1126/science.aam9288"/>
<author initials="R." surname="Hanson"> <refcontent>Science 362</refcontent>
<organization></organization> </reference>
</author>
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<seriesInfo name="Science" value="362" />
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</front> <author initials="C." surname="Miller" fullname="Carl Miller"/>
<seriesInfo name="NISTIR" value="8240" /> <author initials="D." surname="Moody" fullname="Dustin Moody"/>
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<!-- <!--
<reference anchor="Unruh" target="https://link.springer.com/content/pdf/ 10.1007/978-3-662-44381-1_1.pdf"> <reference anchor="Unruh" target="https://link.springer.com/content/pdf/ 10.1007/978-3-662-44381-1_1.pdf">
<front> <front>
<title>Quantum Position Verification in the Random Oracle Model</title> <title>Quantum Position Verification in the Random Oracle Model</title>
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<organization></organization> <organization></organization>
</author> </author>
<date year="2014" /> <date year="2014" />
</front> </front>
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t>
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<reference anchor="ITUT" target="https://www.itu.int/md/T22-SG13-221125- <reference anchor="BBM92" target="https://link.aps.org/doi/10.1103/PhysRev
TD-WP3-0158/en"> Lett.68.557">
<front> <front>
<title>Draft New Technical Report ITU-T TR.QN-UC:"Use Cases of Quantum <title>Quantum cryptography without Bell's theorem</title>
Networks beyond QKDN"</title> <author initials="C. H." surname="Bennett" fullname="Charles H. Bennet
<author initials="" surname="ITU-T SG13-TD158/WP3" /> t">
<date year="2022"/> </author>
</front> <author initials="G." surname="Brassard" fullname="Gilles Brassard">
<!--<seriesInfo name="National Security Agency" value=" (NSA)" /> - </author>
-> <author initials="N. D." surname="Mermin" fullname="N. David Mermin">
</reference> </author>
<date month="February" year="1992"/>
</front>
<seriesInfo name="DOI" value="10.1103/PhysRevLett.68.557"/>
<refcontent>Physical Review Letters, American Physical Society</refconten
t>
</reference>
</references> <reference anchor="E91" target="https://link.aps.org/doi/10.1103/PhysRevLe
tt.67.661">
<front>
<title>Quantum cryptography based on Bell's theorem</title>
<author initials="A. K." surname="Ekert">
<organization/>
</author>
<date month="August" year="1991"/>
</front>
<seriesInfo name="DOI" value="10.1103/PhysRevLett.67.661"/>
<refcontent>Physical Review Letters, American Physical Society</refconten
t>
</reference>
</back> <reference anchor="ITUT" target="https://www.itu.int/md/T22-SG13-221125-TD
-WP3-0158/en">
<front>
<title>Draft new Technical Report ITU-T TR.QN-UC: 'Use cases of quantu
m networks beyond QKDN'</title>
<author>
<organization>ITU-T</organization>
</author>
<date year="2022" month="November"/>
</front>
<seriesInfo name="ITU-T" value="SG 13"/>
</reference>
</references>
<section anchor="Acknowledgments" numbered="false" toc="default">
<name>Acknowledgments</name>
<t>The authors want to thank <contact fullname="Michele Amoretti"/>,
<contact fullname="Mathias Van Den Bossche"/>, <contact fullname="Xavier
de Foy"/>, <contact fullname="Patrick Gelard"/>, <contact
fullname="Álvaro Gómez Iñesta"/>, <contact fullname="Mallory Knodel"/>,
<contact fullname="Wojciech Kozlowski"/>, <contact fullname="John Preuß
Mattsson"/>, <contact fullname="Rodney Van Meter"/>, <contact
fullname="Colin Perkins"/>, <contact fullname="Joey Salazar"/>, <contact
fullname="Joseph Touch"/>, <contact fullname="Brian Trammell"/>, and
the rest of the QIRG community as a whole for their very useful reviews
and comments on the document.</t>
</section>
</back>
<!-- [rfced] Acronyms
a) For clarity, may we expand "EPR-pairs" to "Einstein-Podolsky-Rosen pairs",
or is there another expansion intended for this acronym?
Current:
In general,
by sharing EPR-pairs using quantum repeaters, the optical
interferometers can communicate photons over long distances,
providing arbitrarily long baselines [Gottesman2012].
Perhaps:
In general,
by sharing Einstein-Podolsky-Rosen pairs using quantum repeaters,
the optical interferometers can communicate photons over long
distances, providing arbitrarily long baselines [Gottesman2012].
b) To avoid awkward hyphenation ("Diffie-Hellman-based"), may we add the
acronym "DH" in the first instance of "Diffie-Hellman"? Note that there are
four instances of "Diffie-Hellman" and the final three would be updated to
"DH".
Original:
This would negatively affect many of the security
mechanisms currently in use on the Classical Internet that are based
on public-key (Diffie-Hellman) encryption.
...
Interestingly, development of the Quantum Internet will also mitigate
the threats posed by quantum computing attacks against Diffie-Hellman
based public-key cryptosystems.
Perhaps:
This would negatively affect many of the security
mechanisms currently in use on the Classical Internet that are based
on public key (Diffie-Hellman (DH)) encryption.
...
Interestingly, development of the Quantum Internet will also mitigate
the threats posed by quantum computing attacks against DH-based
public key cryptosystems.
-->
<!-- [rfced] Terminology
a) Throughout the text, "Quantum" appears to be capitalized inconsistently.
May we update the instances listed below as follows?
Quantum-based > quantum-based
quantum key distribution > Quantum Key Distribution
Quantum Network > quantum network
b) Please review the usage of the slashes (/) in the following terms and
let us know if they can be replaced with "and", "or", or "and/or" for
clarity.
bits/packets
new client/server computation model
quantum-repeaters/routers
Sensing/Metrology
-->
<!-- [rfced] Some author comments are present in the XML. Please confirm that
no updates related to these comments are outstanding. Note that the
comments will be deleted prior to publication.
-->
<!-- [rfced] Please review the "Inclusive Language" portion of the online
Style Guide <https://www.rfc-editor.org/styleguide/part2/#inclusive_language>
and let us know if any changes are needed.
For example, please consider whether the following should be updated:
man-in-the-middle:
In other words, the quantum
node A and the quantum node B need to authenticate the classical
channel to make sure there is no eavesdroppers or man-in-the-
middle attacks, according to certain authentication protocols
such as [Kiktenko].
-->
<!-- [rfced] Please ensure that the guidelines listed in Section 2.1 of RFC 5743
have been adhered to in this document.
-->
</rfc> </rfc>
 End of changes. 187 change blocks. 
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