<?xml version="1.0"encoding="US-ASCII"?>encoding="UTF-8"?> <!DOCTYPE rfcSYSTEM "rfc2629.dtd"> <?rfc toc="yes"?> <?rfc tocompact="yes"?> <?rfc tocdepth="3"?> <?rfc tocindent="yes"?> <?rfc symrefs="yes"?> <?rfc sortrefs="yes"?> <?rfc comments="yes"?> <?rfc inline="yes"?> <?rfc compact="no"?> <?rfc subcompact="no"?> <?rfc authorship="yes"?> <?rfc tocappendix="yes"?>[ <!ENTITY nbsp " "> <!ENTITY zwsp "​"> <!ENTITY nbhy "‑"> <!ENTITY wj "⁠"> ]> <rfc xmlns:xi="http://www.w3.org/2001/XInclude" submissionType="IETF" category="info" consensus="true" ipr="trust200902"docName="draft-ietf-raw-use-cases-11">docName="draft-ietf-raw-use-cases-11" number="9450" obsoletes="" updates="" xml:lang="en" tocInclude="true" tocDepth="3" symRefs="true" sortRefs="true" version="3"> <front> <title abbrev="RAWUse-Case Scenarios">RAW Use-Cases</title>Use Cases">Reliable and Available Wireless (RAW) Use Cases</title> <seriesInfo name="RFC" value="9450"/> <author role="editor" fullname="Carlos J. Bernardos" initials="CJ." surname="Bernardos"> <organization abbrev="UC3M"> Universidad Carlos III de Madrid </organization> <address> <postal> <street>Av. Universidad, 30</street><city>Leganes, Madrid</city><city>Madrid</city> <code>28911</code> <country>Spain</country> </postal> <phone>+34 91624 6236</phone> <email>cjbc@it.uc3m.es</email> <uri>http://www.it.uc3m.es/cjbc/</uri> </address> </author> <authorinitials="G.Z."initials="G." surname="Papadopoulos" fullname="GeorgiosZ.Papadopoulos"> <organization>IMT Atlantique</organization> <address> <postal><street>Office<extaddr>Office B00 -114A</street>114A</extaddr> <street>2 Rue de la Chataigneraie</street> <city>Cesson-Sevigne - Rennes</city> <code>35510</code><country>FRANCE</country><country>France</country> </postal> <phone>+33 299 12 70 04</phone> <email>georgios.papadopoulos@imt-atlantique.fr</email> </address> </author> <author initials="P" surname="Thubert" fullname="Pascal Thubert"> <organization abbrev="Cisco">Cisco Systems, Inc</organization> <address> <postal><street>Building D</street><extaddr>Building D</extaddr> <street>45 Allee des Ormes - BP1200 </street> <city>MOUGINS - Sophia Antipolis</city> <code>06254</code><country>FRANCE</country><country>France</country> </postal> <phone>+33 497 23 26 34</phone> <email>pthubert@cisco.com</email> </address> </author> <author initials="F." surname="Theoleyre" fullname="Fabrice Theoleyre"> <organization>CNRS</organization> <address> <postal><street>ICube<extaddr>ICube Lab, PoleAPI</street>API</extaddr> <street>300 boulevard Sebastien Brant - CS 10413</street> <city>Illkirch</city> <code>67400</code><country>FRANCE</country><country>France</country> </postal> <phone>+33 368 85 45 33</phone> <email>fabrice.theoleyre@cnrs.fr</email> <uri>https://fabrice.theoleyre.cnrs.fr/</uri> </address> </author><date/> <workgroup>RAW</workgroup><date year="2023" month="August" /> <area>rtg</area> <workgroup>raw</workgroup> <keyword>determinism</keyword> <keyword>availability</keyword> <keyword>routing</keyword> <keyword>path</keyword> <abstract><t> The<t>The wireless medium presents significant specific challenges to achieve properties similar to those of wired deterministic networks. At the same time, a number ofuse-casesuse cases cannot be solved with wires and justify the extra effort of going wireless. This document presents wirelessuse-casesuse cases (such as aeronautical communications, amusement parks, industrial applications, pro audio and video, gaming,UAVUnmanned Aerial Vehicle (UAV) andV2Vvehicle-to-vehicle (V2V) control, edgeroboticsrobotics, and emergencyvehicles)vehicles), demanding reliable and available behavior. </t> </abstract> </front> <middle> <sectiontitle="Introduction"> <t> Basednumbered="true" toc="default"> <name>Introduction</name> <t>Based on time, resource reservation, and policy enforcement by distributedshapers, deterministic networkingshapers <xref target="RFC2475"/>, Deterministic Networking (DetNet) provides the capability to carry specified unicast or multicast data streams for real-time applications with extremely low data loss rates and boundedlatency,latency so as to support time-sensitive and mission-critical applications on a converged enterprise infrastructure. </t><t> Deterministic networking<t>DetNet aims at eliminating packet loss for a committedbandwidthbandwidth, while ensuring aworst caseworst-case end-to-end latency, regardless of the network conditions and across technologies. By leveraging lower layer (Layer 2 (L2) and below) capabilities,L3Layer 3 (L3) can exploit the use of a service layer, steering over multipletechnologies,technologies and using media independent signaling to provide high reliability, precise time delivery, and rate enforcement.Deterministic networkingDetNet can be seen as a set of new Quality of Service (QoS) guarantees of worst-case delivery. IP networks become more deterministic when the effects of statistical multiplexing (jitter and collision loss) are mostly eliminated. This requires a tight control of the physical resources to maintain the amount of traffic within the physical capabilities of the underlying technology, e.g., by using time-shared resources (bandwidth and buffers) per circuit,and/orby shapingand/oror scheduling the packets at everyhop.hop, or by using a combination of these techniques. </t><t> Key<t>Key attributes ofDeterministic networking include: <list style="symbols"> <t>timeDetNet include:</t> <ul spacing="normal"> <li>time synchronization on all thenodes,</t> <t>multi-technologynodes,</li> <li>multi-technology path with co-channel interferenceminimization,</t> <t>frameminimization,</li> <li>frame preemption and guard time mechanisms to ensure a worst-case delay,and</t> <t>newand</li> <li>new trafficshapersshapers, both within and at theedgeedge, to protect thenetwork.</t> </list> </t> <t> Wirelessnetwork.</li> </ul> <t>Wireless operates on a shared medium, and transmissions cannot be guaranteed to be fully deterministic due to uncontrolled interferences, including self-induced multipath fading. The term RAW stands forReliable"Reliable and AvailableWireless,Wireless" and refers to the mechanisms aimed for providing high reliability and availability for IP connectivity over a wireless medium. MakingWireless Reliablewireless reliable andAvailableavailable is even more challenging than it is with wires, due to the numerous causes of loss in transmission that add up to the congestion losses and due to the delays caused by overbooked sharedresources. </t> <t> Theresources.</t> <t>The wireless and wired media are fundamentally different at the physicallevel, and whilelevel. While the generic Problem Statement in <xreftarget="RFC8557"/>target="RFC8557" format="default"/> for DetNet applies to the wired as well as the wireless medium, the methods to achieve RAW necessarily differ from those used to support Time-Sensitive Networking over wires, e.g., due to the wireless radio channelspecifics. </t> <t> Sospecifics.</t> <t>So far, open standards fordeterministic networkingDetNet have prevalently been focused on wired media, withAudio/VideoAudio Video Bridging (AVB) andTime SensitiveTime-Sensitive Networking (TSN) at the IEEE and DetNet <xreftarget="RFC8655"/>target="RFC8655" format="default"/> at the IETF.ButHowever, wires cannot be used in several cases, including mobile or rotating devices, rehabilitated industrial buildings, wearable or in-body sensory devices, vehicleautomationautomation, and multiplayer gaming. </t><t> Purpose-built<t>Purpose-built wireless technologies such as <xreftarget="ISA100"/>,target="ISA100" format="default"/>, which incorporates IPv6, were developed and deployed to cope with the lack of open standards, but they yield a high cost inOPEXOperational Expenditure (OPEX) andCAPEXCapital Expenditure (CAPEX) and are limited to very few industries, e.g., process control, concertinstrumentsinstruments, or racing. </t><t> This<t>This is now changing (as detailed in <xreftarget="I-D.ietf-raw-technologies"/>: <list style="symbols"> <t> IMT-2020target="I-D.ietf-raw-technologies" format="default"/>):</t> <ul spacing="normal"> <li>IMT-2020 has recognized Ultra-ReliableLow-LatencyLow Latency Communication (URLLC) as a key functionality for the upcoming 5G.</t> <t> IEEE</li> <li>IEEE 802.11 has identified a set ofreal-applicationsreal applications <xreftarget="IEEE80211-RT-TIG"/>target="IEEE80211RTA" format="default"/>, which may use the IEEE802.11 standards. They typically emphasize strict end-to-end delay requirements.</t> <t> The</li> <li>The IETF has produced an IPv6 stack for IEEE Std. 802.15.4TimeSlottedTime-Slotted Channel Hopping (TSCH) and an architecture <xreftarget="RFC9030"/>target="RFC9030" format="default"/> that enables RAW on a shared MAC.</t> </list> </t> <!--FT: recent experiments with TSN + WiFi 7 --> <t> Experiments</li> </ul> <t>Experiments have already been conducted with IEEE802.1 TSN over IEEE802.11be <xreftarget="IEEE80211BE"/>.target="IEEE80211BE" format="default"/>. This mode enables timesynchronization,synchronization and time-aware scheduling (trigger based access mode) to support TSNflows. </t> <t> Thisflows.</t> <t>This document extends the"Deterministic Networking use-cases""<xref target="RFC8578" format="title"/>" document <xreftarget="RFC8578"/>target="RFC8578" format="default"/> and describes several additionaluse-cases whichuse cases that require "reliable/predictable and available" flows over wireless links and possibly complex multi-hop paths calledTracks."Tracks". This is covered mainly by the "Wireless for Industrial Applications"use-case,(<xref target="RFC8578" sectionFormat="of" section="5"/>) use case, as the "Cellular Radio" (<xref target="RFC8578" sectionFormat="of" section="6"/>) is mostly dedicated to the (wired) link part of a Radio Access Network (RAN).WhereasWhereas, while the "Wireless for Industrial Applications"use-caseuse case certainly covers an area of interest for RAW, it is limited to6TiSCH,IPv6 over the TSCH mode of IEEE 802.15.4e (6TiSCH), andthusthus, its scope is narrower than theuse-casesuse cases described next in this document. </t> </section> <sectiontitle="Aeronautical Communications"> <t> Aircraftnumbered="true" toc="default"> <name>Aeronautical Communications</name> <t>Aircraft are currently connected toATC (Air-Traffic Control)Air-Traffic Control (ATC) andAOC (AirlineAirline OperationalControl)Control (AOC) via voice and data communication systems through all phases of a flight. Within the airport terminal, connectivity is focused onhigh bandwidth communications while en-routehigh-bandwidth communications, whereas en route it's focused on high reliability,robustnessrobustness, andrange are the focus.range. </t> <sectiontitle="Problem Statement"> <t> Upnumbered="true" toc="default"> <name>Problem Statement</name> <t>Up to 2020, civil air traffichashad been growing constantly at a compound rate of 5.8% per year <xreftarget="ACI19"/>target="ACI19" format="default"/>, and despite the severe impact of the COVID-19 pandemic,air trafficair-traffic growth is expected to resume very quickly in post-pandemic times <xreftarget="IAT20"/>target="IAT20" format="default"/> <xreftarget="IAC20"/>.target="IAC20" format="default"/>. Thus, legacy systems inair traffic managementAir-Traffic Management (ATM) are likely to reach their capacitylimitslimits, and the need for new aeronautical communication technologies becomes apparent. Especially problematic is the saturation of VHF band in high density areas in Europe, the US, and Asia <xreftarget="KEAV20"/>target="SESAR" format="default"/> <xreftarget="FAA20"/>target="FAA20" format="default"/>, calling for suitable new digital approaches such asAeroMACSthe Aeronautical Mobile Airport Communications System (AeroMACS) for airport communications, SatCOM for remote domains, andLDACSthe L-band Digital Aeronautical Communication System (LDACS) as the long-range terrestrial aeronautical communication system. Making the frequency spectrum's usage a more efficientatransition from analog voice to digital data communication <xreftarget="PLA14"/>target="PLA14" format="default"/> is necessary to cope with the expected growth of civil aviation and its supporting infrastructure. A promising candidate forlong rangelong-range terrestrial communications, already in the process of being standardized in the International Civil Aviation Organization (ICAO), isthe L-band Digital Aeronautical Communication System (LDACS)LDACS <xreftarget="ICAO18"/>target="ICAO2022" format="default"/> <xreftarget="I-D.ietf-raw-ldacs"target="RFC9372" format="default"/>. </t><t> Note<t>Note that the large scale of the plannedlowLow EarthorbitOrbit (LEO) constellations of satellites can provide fast end-to-end latency rates and high data-rates at a reasonable cost, but they also posechallengeschallenges, such as frequent handovers,high-interference,high interference, and a diverse range of system users, which can create security issues since both safety-critical andnon-safety-criticalnot safety-critical communications can take place on the same system. Some studies suggest that LEO constellations could be a complete solution for aeronautical communications, but they do not offer solutions for the critical issues mentioned earlier. Additionally, of the three communication domains defined by ICAO, only passenger entertainment services can currently be provided using these constellations. Safety-critical aeronautical communications require reliability levels above 99.999%, which is higher than that required for regular commercial data links. Therefore, addressing the issues with LEO-based SatCOM is necessary before these solutions can reliably support safety-critical data transmission <xref target="Maurer2022"/>.format="default"/>. </t> </section> <sectiontitle="Specifics">numbered="true" toc="default"> <name>Specifics</name> <t> During the creation process of a new communication system, analog voice is replaced by digital data communication. This sets a paradigm shift from analog to digital wireless communications and supports the related trend towards increased autonomous data processing that the Future Communications Infrastructure (FCI) in civil aviation must provide. The FCI is depicted in <xreftarget="fig_LDACS"/>:target="fig_LDACS" format="default"/>: </t> <figuretitle="Theanchor="fig_LDACS"> <name>The Future Communication Infrastructure(FCI): AeroMACS for Airport/Termina Maneuvering Area domain, LDACS A/G for Terminal Maneuvering/En-Route domain, LDACS A/G for En-Route/Oceanic, Remote, Polar domain, SatCOM for Oceanic, Remote, Polar domain domain communications" anchor="fig_LDACS"> <artwork> <![CDATA[(FCI)</name> <artwork name="" type="" align="left" alt=""><![CDATA[ Satellite # # # # # # # # # # # # # # # # # # # # # Satellite-based # # # Communications # # # SatCOM (#) # # # # Aircraft # # % % # # % % # # % Air-Air % # # % Communications % # # % LDACS A/A (%) % # # % % # Aircraft % % % % % % % % % % Aircraft # | Air-Ground | # | Communications | # | LDACS A/G (|) | # Communications in | | # and around airports | | # AeroMACS (-) | | # | | # Aircraft-------------+ | | # | | | # | | | # Ground network | | Ground network | SatCOM <---------------------> Airport <----------------------> LDACS ground ground ground transceiver transceiver transceiver]]> </artwork>]]></artwork> </figure></section> <section title="Challenges"> <t> This<t>FCI includes:</t> <ul spacing="compact"> <li>AeroMACS for airport and terminal maneuvering area domains,</li> <li>LDACS Air/Ground for terminal maneuvering area and en route domains,</li> <li>LDACS Air/Ground for en route or oceanic, remote, and polar regions, and</li> <li>SatCOM for oceanic, remote, and polar regions.</li> </ul> </section> <section numbered="true" toc="default"> <name>Challenges</name> <t>This paradigm change brings a lot of newchallenges: <list style="symbols"> <t> Efficiency:challenges:</t> <ul spacing="normal"> <li>Efficiency: It is necessary to keep latency,timetime, and data overhead of new aeronauticaldatalinks atdata links to aminimum. </t> <t> Modularity:minimum.</li> <li>Modularity: Systems in avionics usually operate for up to 30years, thusyears. Thus, solutions must be modular, easilyadaptableadaptable, andupdatable. </t> <t> Interoperability:updatable.</li> <li>Interoperability: All 192 members of theinternational Civil Aviation Organization (ICAO)ICAO must be able to use thesesolutions. </t> <t> <!-- FT: dynamic topology (very high mobility)-->solutions.</li> <li> Dynamicity:theThe communication infrastructure needs to accommodate mobile devices (airplanes) that move extremelyfast. </t> </list> </t>fast.</li> </ul> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> InWireless</name> <t>In ahigh mobility environmenthigh-mobility environment, such as aviation, the envisioned solutions to provide worldwide coverage of data connections with in-flight aircraft require a multi-system, multi-link, multi-hop approach.ThusThus, air,groundground, and space-baseddatalink providingdata links that provide these technologies will have to operate seamlessly together to cope with the increasing needs of data exchange between aircraft,air trafficair-traffic controller, airport infrastructure, airlines, air network service providers(ANSPs)(ANSPs), and so forth. Wireless technologies have to be used to tackle this enormous need for a worldwide digital aeronauticaldatalinkdata link infrastructure. </t> </section> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> DifferentRAW</name> <t>Different safety levels need to be supported. All network traffic handled by the Airborne Internet Protocol Suite (IPS) Systemisare notequalequal, and theQuality of Service (QoS)QoS requirements of each network traffic flow must be considered n order to avoid having to support QoS requirements at the granularity of dataflows, theseflows. These flows are grouped into classes that have similar requirements, following theDiffServDiffserv approach <xref target="ARINC858P1"/>.format="default"/>. These classes are referred to as Classes of Service(CoS)(CoS), and the flows within a class are treated uniformly from a QoS perspective. Currently, there are at least eight different priority levels (CoS) that can be assigned to packets. For example, a high-priority message requiring low latency and high resiliency could be a "WAKE" warning indicating two aircraft are dangerously close to each other, while a less safety-critical message withlow-mediumlow-to-medium latency requirements could be the "WXGRAPH" service providing graphical weather data. </t><t> Overhead<t>Overhead needs to be keptatto a minimum since aeronautical data links provide comparatively small data rates on the order of kbit/s. </t><t> Policy<t>Policy needs to be supported when selecting data links. The focus of RAW here should be on theselectors,selectors that are responsible for the track a packet takes to reach its end destination. This would minimize the amount of routing information that must travel inside the network because of precomputed routingtablestables, with the selector being responsible for choosing the most appropriate option according to policy and safety. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Achievingnumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>Achieving low latency is a requirement for aeronautics communications, though the expected latency is not extremelylowlow, and what is important is to keep the overall latency bounded under a certain threshold. Low latency in LDACS communications <xref target="RFC9372"/>format="default"/> translates to a latency in the Forward Link (FL - Ground->-> Air) of 30-90 ms and a latency in the Reverse Link (RL - Air->-> Ground) of 60-120 ms. Thisuse-caseuse case is notlatency-criticallatency critical from that view point. On the other hand, given the controlled environment, end-to-end mechanisms can be applied to guarantee bounded latency where needed. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Amusement Parks"> <section title="Use-Case Description"> <t> Thenumbered="true" toc="default"> <name>Amusement Parks</name> <section numbered="true" toc="default"> <name>Use Case Description</name> <t>The digitalization ofAmusement Parksamusement parks is expected todecreasesignificantly decrease the cost for maintaining the attractions. Such deployment is a mix between multimedia (e.g., Virtual and AugmentedReality,Reality and interactive video environments) and non-multimedia applications (e.g, access control, industrial automation for aroller-coaster, access control).roller coaster). </t><t> Attractions<t>Attractions may rely on a large set of sensors and actuators, which react in real time. Typical applications comprise: </t><t> <list style="symbols"> <t> Emergency:<ul spacing="normal"> <li>Emergency: the safety of the operators/and visitors has to bepreservedpreserved, and the attraction must be stopped appropriately when a failure isdetected. </t> <t> Video:detected.</li> <li>Video: augmented and virtual realities are integrated in the attraction. Wearable mobile devices (e.g.,glasses,glasses and virtual realityheadset)headsets) need to offload one part of the processingtasks. </t> <t> Real-timetasks.</li> <li>Real-time interactions: visitors may interact with an attraction, like in a real-time video game. The visitors may virtually interact with their environment, triggering actions in the real world (through actuators) <xreftarget="KOB12"/>. </t> <t> Geolocation:target="KOB12" format="default"/>.</li> <li>Geolocation: visitors are tracked with a personal wirelesstagtag, so that their user experience is improved. This requires special care to ensure that visitors' privacy is not breached, and users are anonymouslytracked. </t> <t> Predictivetracked.</li> <li>Predictive maintenance: statistics are collected to predict the futurefailures,failures or to compute later more complex statistics about the attraction's usage, the downtime,etc. </t> <t> Marketing:etc.</li> <li>Marketing: to improve the customer experience, owners may collect a large amount of data to understand thebehavior,behavior and thechoicechoices of theirclients. </t> </list> </t>clients.</li> </ul> </section> <sectiontitle="Specifics"> <t> Amusementnumbered="true" toc="default"> <name>Specifics</name> <t>Amusement parks comprise a variable number of attractions, mostly outdoor, over a large geographical area. The IT infrastructure is typicallymulti-scale: <list style="symbols"> <t> Localmultiscale:</t> <ul spacing="normal"> <li>Local area:theThe sensors and actuators controlling the attractions areco-located.colocated. Control loops trigger only local traffic, with a small end-to-end delay, typically less than 10 ms, like classical industrial systems <xreftarget="IEEE80211-RT-TIG"/>. </t> <t>target="IEEE80211RTA" format="default"/>.</li> <li>Wearable devices: Wearable mobile devices are free to move in the park. They exchange traffic locally (identification, personalization, multimedia) or globally (billing,child tracking). </t> <t>child-tracking).</li> <li>Edge computing: Computationally intensive applications offload some tasks. Edge computing seems to be an efficient way to implement real-time applications with offloading. Some non-time-critical tasks may rather use the cloud (predictive maintenance,marketing). </t> </list> </t>marketing).</li> </ul> <t> </t> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> RemovingWireless</name> <t>Removing cables helps tochangeeasily change the configuration of theattractions,attractions ortoupgrade parts of them at a lower cost. The attraction can be designedmodularly,modularly and can upgrade or insert novel modules later on in thelifecyclelife cycle of the attraction. Novelty of attractions tends to increase the attractiveness of an amusement park, encouraging previous visitors tovisitregularly visit the park. </t><t> Some<t>Some parts of the attraction are mobile, like trucks of a roller-coaster or robots. Since cables are prone to frequent failures in this situation, wireless transmissions are recommended. </t><t> Wearable<t>Wearable devices are extensively used for a user experience personalization. They typically need to support wireless transmissions. Personal tags may help to reduce the operating costs <xreftarget="DISNEY15"/>target="DISNEY15" format="default"/> andtoincrease the number of charged services provided to the audience (e.g., VIP tickets or interactivity). Some applications rely on more sophisticated wearabledevicesdevices, such as digital glasses or Virtual Reality (VR) headsets for an immersive experience. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> TheRAW</name> <t>The network infrastructure must support heterogeneous traffic, with very different critical requirements. Thus, flow isolation must be provided. </t><t> The<t>The transmissions must be scheduledappropriatelyappropriately, even in the presence of mobile devices. Whilethe<xreftarget="RFC9030"/>target="RFC9030" format="default"/> already proposes an architecture for synchronized, IEEE Std. 802.15.4 Time-Slotted Channel Hopping (TSCH) networks, the industry requires a multi-technologysolution,solution that is able to guarantee end-to-end requirements across heterogeneoustechnologies,technologies with strictSLAService Level Agreement (SLA) requirements. </t><t> Nowadays,<t>Nowadays, long-range wireless transmissions are used mostly for best-effort traffic. On the contrary, <xreftarget="IEEE802.1TSN"/>target="IEEE802.1AS" format="default"/> is used for critical flows using Ethernet devices. However, we need anIP enabledIP-enabled technology to interconnect large areas, independent of thePHYPhysical (PHY) andMACMedium Access Control (MAC) layers. </t><t> It<t>It is expected that several different technologies (long vs. short range) are deployed, which have to cohabitinthe same area. Thus, we need to providelayer-3L3 mechanisms able to exploit multiple co-interfering technologies (i.e., different radio technologies using overlapping spectrum, and therefore, potentially interferingtowith each other). </t><t> It<t>It is worth noting that low-priority flows (e.g., predictive maintenance, marketing) are delaytolerant:tolerant; a few minutes or even hours would be acceptable. While classical unscheduled wireless networks alreadyaccomodateaccommodate best-effort traffic, this would force several colocated and subefficient deployments. Unused resources could rather be used for low-priority flows. Indeed, allocated resources are consuming energy in most scheduled networks, even if no traffic is transmitted. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations">numbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t> While some of the applications in thisuse-caseuse case involve control loops (e.g., sensors and actuators) that require bounded latencies below 10ms,ms that can therefore be considered latency critical, there are other applications as well that mostly demand reliability (e.g.,safety related,safety-related or maintenance). </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Wirelessnumbered="true" toc="default"> <name>Wireless for IndustrialApplications">Applications</name> <sectiontitle="Use-Case Description">numbered="true" toc="default"> <name>Use Case Description</name> <t><!-- FT: several sensors may be attached to the PLC -->A majoruse-caseuse case for networking inIndustrialindustrial environments is the control networks where periodic control loops operate between a collection of sensors that measure a physical propertysuch(such as the temperature of afluid,fluid), a Programmable Logic Controller (PLC) that decides on an actionsuch(such aswarm"warm up themix,mix"), and actuators that perform the requiredaction, suchaction (such as the injection of power in aresistor.resistor). </t> </section> <section anchor="indusspecif"title="Specifics">numbered="true" toc="default"> <name>Specifics</name> <section anchor="indusloops"title="Control Loops"> <t> Processnumbered="true" toc="default"> <name>Control Loops</name> <t>Process Control designates continuous processing operations, like heating oil in a refinery or mixingdrinkingup soda. Control loops in the Process Control industry operate at a very low rate, typically four times per second. Factory Automation, on the other hand, deals with discretegoodsgoods, such as individual automobile parts, and requires faster loops,onto theorderrate of milliseconds. Motion control that monitors dynamic activities may require even faster rates on the order of and below the millisecond. </t><t> In<t>In all those cases, a packet must flow reliably between the sensor and the PLC, be processed by the PLC, and be sent to the actuator within the control loop period. In some particularuse-casesuse cases that inherit from analog operations, jitter might also alter the operation of the control loop. A rare packet loss is usually admissible, buttypicallytypically, a loss of multiple packets in a row will cause an emergency halt of the production and incur a high cost for the manufacturer. </t><t> Additional<t>Additional details anduse-casesuse cases related toIndustrialindustrial applications and their RAW requirements can be found in <xref target="I-D.ietf-raw-industrial-requirements"/>.format="default"/>. </t></section><!--"Control</section> <!--"Control Loops"--> <section anchor="indusdiags"title="Monitoringnumbered="true" toc="default"> <name>Monitoring anddiagnostics"> <t> ADiagnostics</name> <t>A secondaryuse-caseuse case deals with monitoring and diagnostics. This data is essential to improve the performance of a production line, e.g., by optimizing real-time processing or by maintenance windows using Machine Learning predictions. For the lack of wireless technologies, some specific industries such as Oil and Gas have been using serial cables, literally by the millions, to perform their process optimization over the previous decades.ButHowever, few industries would afford the associated cost. One of the goals of the Industrial Internet of Things is to provide the same benefits to all industries, including SmartGrid,Transportation, Building, Commercialtransportation, building, commercial, andMedical.medical. This requires a cheap,availableavailable, and scalable IP-based access technology. </t><t> Inside<t>Inside the factory, wires may already be available to operate theControl Network. Butcontrol network. However, monitoring and diagnostics data are not welcome in that network for several reasons. On the onehandhand, it is rich and asynchronous, meaning that it may influence the deterministic nature of the control operations and impact the production. On the other hand, this information must be reported to the operators over IP, which means the potential for a security breach via the interconnection of the Operational Technology(OT)network with the Internettechnology (IT)Technology network andpossibly enablethe potential of a rogue access. </t></section><!--</section> <!-- "Monitoring and diagnostics" --> </section> <!--title="Speficicitiestitle="Specifics --> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> WiresWireless</name> <t>Wires used on a robot arm are prone tobreakagebreakage, after a fewthousandsthousand flexions, a lot faster than a power cable that is wider indiameter,diameter and more resilient. In general, wired networking and mobile parts are not a good match, mostly in the case of fast and recurrent activities, as well as rotation. </t><t> When<t>When refurbishing older premises that were built before the Internet age, power is usually available everywhere, but data is not. It is often impractical, time consuming and expensive to deploy an Ethernet fabric across walls and between buildings. Deploying a wire may take months and cost tens of thousands of US Dollars. </t><t> Even<t>Even when wiring exists, like in the case of an existing control network, asynchronous IPpacketspackets, such asdiagnosticsdiagnostics, may not be welcome for operational and security reasons. For those packets, the option to create a parallel wireless network offers a credible solution that can scale with the many sensors and actuators that equip every robot,every valvevalve, and fan that are deployed on the factory floor. It may also help detect and prevent a failure that could impact the production, like the degradation (vibration) of a cooling fan on the ceiling. IEEE Std. 802.15.4Time-Slotted Channel Hopping (TSCH)TSCH <xreftarget="RFC7554"/>target="RFC7554" format="default"/> is a promising technology for that purpose, mostly if the scheduled operations enabletothe use of the same network by asynchronous and deterministic flows in parallel. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> AsRAW</name> <t>As stated by the <xreftarget="RFC8557">target="RFC8557" format="default"> "Deterministic Networking ProblemStatement" </xref>,Statement"</xref>, a deterministic network is backwards compatible with (capable of transporting) statistically multiplexed traffic while preserving the properties of the accepted deterministic flows. While the <xreftarget="RFC9030">6TiSCH Architecture</xref>target="RFC9030" format="default">"6TiSCH Architecture"</xref> serves that requirement, the work at 6TiSCH was focused on best-effort IPv6 packet flows. RAW should be able to lock so-calledhard cells"hard cells" (i.e., scheduled cells <xreftarget="I-D.ietf-6tisch-terminology"/>)target="I-D.ietf-6tisch-terminology" format="default"/>) for use by a centralizedscheduler,scheduler and leverage time and spatial diversity over a graph of end-to-end paths called aTrack"Track" that is based on those cells. </t><t> Over the course of the<t>Over recent years, majorIndustrial Protocols (e.g.,industrial protocols have been migrating towards Ethernet and IP. (For example, <xref target="ODVA"/> with EtherNet/IP <xref target="EIP"/> and <xreftarget="PROFINET"/>) have been migrating towards Ethernet and IP.target="PROFINET"/>, where ODVA is the organization that supports network technologies built on the Common Industrial Protocol (CIP) including EtherNet/IP.) In order to unleash the full power of the IP hourglass model, it should be possible to deploy any application over any network that has the physical capacity to transport the industrial flow, regardless of the MAC/PHY technology,wiredwired, or wireless, and across technologies. RAW mechanisms should be able tosetupset up a Track over a wireless access segment and a wired or wireless backbone to report both sensor data and critical monitoring within a bounded latency and should be able to maintain the high reliability of the flows over time. It is also important to ensure that RAW solutions are interoperable with existing wireless solutions inplace,place and with legacy equipment whose capabilities can be extended using retrofitting. Maintainability, as a broader concept thanreliabilityreliability, is also important in industrial scenarios <xref target="MAR19"/>.format="default"/>. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Monitoringnumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>Monitoring and diagnostics applications do not requirelatency critical communications,latency-critical communications but demand reliable and scalable communications. On the other hand,process controlprocess-control applications involve control loops that require a boundedlatency, thuslatency and, thus, are latencycritical, butcritical. However, they can be managed end-to-end, and therefore DetNet mechanisms can be applied in conjunction with RAW mechanisms. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Pronumbered="true" toc="default"> <name>Professional Audio andVideo">Video</name> <sectiontitle="Use-Case Description"> <t> Manynumbered="true" toc="default"> <name>Use Case Description</name> <t>Many devices support audio and video streaming <xref target="RFC9317"/>format="default"/> by employing 802.11 wireless LAN. Some of these applications require low latencycapability. Forcapability, for instance, when the application provides interactiveplay,play or when the audio plays in real time--- meaning being live for public addresses in train stations or in theme parks. </t><t> The<t>The professional audio and video industry("ProAV")(ProAV) includes:<list style="symbols"> <t> Virtual</t> <ul spacing="normal"> <li>Virtual Reality / Augmented Reality (VR/AR)</t> <t> Production</li> <li>Production and post-productionsystemssystems, such as CD and Blu-ray diskmastering. </t> <t> Publicmastering.</li> <li>Public address,mediamedia, and emergency systems at large venues (e.g., airports, train stations, stadiums, and themeparks). </t> </list> </t>parks).</li> </ul> </section> <sectiontitle="Specifics">numbered="true" toc="default"> <name>Specifics</name> <sectiontitle="Uninterruptednumbered="true" toc="default"> <name>Uninterrupted StreamPlayback"> <t> ConsideringPlayback</name> <t>Considering the uninterrupted audio or video stream, a potential packet loss during the transmission of audio or video flows cannot be tackled by re-trying the transmission, as it is done with file transfer, because by the time thepacketlost packet has beenidentifiedidentified, it is too late to proceed with packet re-transmission. Buffering might be employed to provide a certain delaywhichthat will allow for one or morere-transmissions, howeverre-transmissions. However, such an approach is not viable inapplicationapplications where delays are not acceptable. </t> </section> <sectiontitle="Synchronizednumbered="true" toc="default"> <name>Synchronized StreamPlayback"> <t> InPlayback</name> <t>In the context of ProAV over packet networks, latency is the time between the transmitted signal over a stream and its reception. Thus, for sound to remain synchronized to the movement in the video, the latency of both the audio and video streams must be bounded and consistent. </t> </section> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> TheWireless</name> <t>Audio and video devices need the wireless communication to support video streaming via IEEE 802.11 wirelessLANLAN, for instance. Wireless communications provide huge advantages in terms of simpler deployments in manyscenarios,scenarios where the use of a wired alternative would not be feasible. Similarly, in live events, mobility support makes wireless communications the only viable approach. </t><t> Deployed<t>Deployed announcement speakers, forinstanceinstance, along the platforms of the train stations, need the wireless communication to forward the audio traffic in real time. Most train stations are already built, and deploying novel cables for each novel service seems expensive. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> TheRAW</name> <t>The network infrastructure needs to support heterogeneous types of traffic (including QoS). </t><t> Content<t>Content deliverywithmust have bounded(lowest possible) latency. </t> <t> Thelatency (to the lowest possible latency).</t> <t>The deployed network topology should allow for multipath. This will enable for multiple streams to have different (and multiple) paths(tracks)(Tracks) through the network to support redundancy. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Fornumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>For synchronized streaming, latency must bebounded, and therefore,bounded. Therefore, depending on the actual requirements, this can be considered aslatency critical."latency critical". However, the most critical requirement of thisuse-caseuse case is reliability, which can be achieved by the network providing redundancy. Note that in many cases, wireless is only present in theaccess,access where RAW mechanisms could be applied, but other wired segments are also involved (like the Internet), and therefore latency cannot be guaranteed. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Wireless Gaming"> <section title="Use-Case Description"> <t> Thenumbered="true" toc="default"> <name>Wireless Gaming</name> <section numbered="true" toc="default"> <name>Use Case Description</name> <t>The gaming industry includes <xref target="IEEE80211RTA"/>format="default"/> real-time mobile gaming, wireless console gaming, wireless gamingcontrollerscontrollers, and cloud gaming. Note that they are not mutually exclusive (e.g., a console can connect wirelessly to the Internet to play a cloud game). For RAW, wireless console gaming is the most relevant one. We next summarize thefour: <list style="symbols"> <t> Real-time Mobile Gaming: Different from traditional games, real timefour:</t> <ul spacing="normal"> <li><t>Real-time mobile gaming:</t> <t>Real-time mobile gaming is very sensitive to network latency and stability. The mobile game can connect multiple players together in a single game session and exchange data messages between game server and connected players. Real-time means the feedback should presenton screenon-screen as users operatein game.in-game. For good game experience, the end-to-end(E2E)latency plus game servers processing time must be the same for all players and should not be noticeable as the game is played. RAW technologies might help in keeping latencies low on the wireless segments of thecommunication. </t> <t> Wireless Console Gaming: whilecommunication.</t></li> <li><t>Wireless console gaming:</t> <t>While gamers may use a physical console, interactions with a remote server may be required for online games. Most of the gaming consoles today support Wi-Fi5,5 but may benefit from a scheduled access with Wi-Fi 6 in the future. Previous Wi-Fi versions have an especially bad reputation among the gamingcommunity. Thecommunity, the main reasonsarebeing high latency, lag spikes, andjitter. </t> <t> Wirelessjitter.</t></li> <li><t>Wireless Gamingcontrollers: mostcontrollers:</t> <t>Most controllers are now wireless forathe freedom ofmovement.Controllersmovement. Controllers may interact with consoles or directly with the gaming server in the cloud. A low and stable end-to-end latency is here of predominantimportance. </t> <t> Cloud Gaming: The cloudimportance.</t></li> <li><t>Cloud Gaming:</t> <t>Cloud gaming requireslow latencylow-latency capability as the user commands in a game sessionneed to beare sent back to the cloudserver,server. Then, the cloud serverwould updateupdates the game context depending on the received commands,and the cloud server would renderrenders the picture/video to be displayedaton the userdevicesdevices, andstreamstreams the picture/video content to the user devices. User devices might very likely be connectedwirelessly. </t> </list> </t>wirelessly.</t></li> </ul> </section> <sectiontitle="Specifics"> <t> Whilenumbered="true" toc="default"> <name>Specifics</name> <t>While a lot of details can be foundonat <xref target="IEEE80211RTA"/>,format="default"/>, we next summarize the main requirements in terms of latency,jitterjitter, and packet loss:<list style="symbols"> <t> Intra</t> <ul spacing="normal"> <li>Intra Basic Service Set (BSS) latency is less than 5ms. </t> <t> Jitterms.</li> <li>Jitter variance is less than 2ms. </t> <t> Packetms.</li> <li>Packet loss is less than0.1 percent. </t> </list> </t>0.1%.</li> </ul> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> GamingWireless</name> <t>Gaming is evolving towards wireless, as players demand being able to play anywhere, and the game requires a more immersive experience including body movements. Besides, the industry is changing towards playing from mobile phones, which are inherently connected via wireless technologies.<!-- FT=: wireless controllers (haptic, etc.) -->Wireless controllers are the rule in modern gaming, with increasingly sophisticated interactions (e.g., haptic feedback, augmented reality). </t> </section> <sectiontitle="Requirements for RAW"> <t> <list style="symbols"> <t> Time sensitivenumbered="true" toc="default"> <name>Requirements for RAW</name> <dl spacing="normal" newline="true"> <dt>Time-sensitive networkingextensions: extensions,extensions:</dt> <dd>Extensions, such as time-aware shaping andredundancyredundancy, can be explored to address congestion and reliability problems present in wireless networks. As an example, inhapticshaptics, it is very important to minimize latencyfailures. </t> <t> Priorityfailures.</dd> <dt>Priority tagging (Streamidentification): oneidentification):</dt> <dd>One basic requirement to provide better QoS for time-sensitive traffic is the capability to identify and differentiate time-sensitive packets from other (like best-effort)traffic. </t> <t> Time-aware shaping: thistraffic.</dd> <dt>Time-aware shaping:</dt> <dd>This capability (defined in IEEE 802.1Qbv) consists of gates to control theopening/closingopening and closing of queues that share a common egress port within an Ethernet switch. A scheduler defines the times when each queue opens orclose, thereforecloses, therefore, eliminating congestion and ensuring that frames are delivered within the expected latency bounds.Note though,Though, note that while this requirement needs to besignalledsignaled by RAW mechanisms, it wouldbeactually be served by the lowerlayer. </t> <t> Dual/multiple link: duelayer.</dd> <dt>Dual/multiple link:</dt> <dd>Due to the fact that competitions and interference are common and hardly in control under wireless network, to improve the latency stability, dual/multiple link proposal is brought up to address thisissue. </t> <t> Admission Control: congestionissue.</dd> <dt>Admission Control:</dt> <dd>Congestion is a major cause of high/variablelatencylatency, and it is well known that if the traffic load exceeds the capability of the link, QoS will be degraded. QoS degradation may be acceptable for many applicationstoday, howevertoday. However, emerging time-sensitive applications are highly susceptible to increased latency and jitter. To better control QoS, it is important to control access to the networkresources. </t> </list> </t>resources.</dd> </dl> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Dependingnumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>Depending on the actual scenario, and on use of Internet to interconnect different users, the communication requirements of thisuse-caseuse case might be considered as latency critical due to the need of bounded latency.ButHowever, notethatthat, in most of these scenarios, part of the communication path is notwirelesswireless, and DetNet mechanisms cannot be applied easily (e.g., when the public Internet is involved), andtherefore in these cases,therefore, reliability is the critical requirement. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Unmannednumbered="true" toc="default"> <name>Unmanned Aerial Vehicles and Vehicle-to-VehicleplatooningPlatooning andcontrol">Control</name> <sectiontitle="Use-Case Description"> <t> Unmannednumbered="true" toc="default"> <name>Use Case Description</name> <t>Unmanned Aerial Vehicles (UAVs) are becoming very popular for many different applications, including military and civiluse-cases.use cases. The termdrone"drone" is commonly used to refer to a UAV. </t> <t><!-- FT: ref for ths spanish app? (I also inserted the medicine app, quite popular in Africa) -->UAVs can be used to perform aerial surveillance activities, traffic monitoring (i.e., the Spanish traffic control has recently introduced a fleet of drones for quicker reactions upon traffic congestion related events <xref target="DGT2021"/>),format="default"/>), support of emergency situations, and eventransportationtransporting of small goods (e.g., medicine in rural areas). Note that the surveillance and monitoring application would have to comply with local regulations regarding location privacy of users. Different considerations have to be applied when surveillance is performed for traffic rules enforcement (e.g., generatingfines)fines), as compared to when traffic load is being monitored. </t><t> Many<t>Many types of vehicles, including UAVs but also others, such as cars, can travel in platoons, driving together with shorter distances between vehicles to increase efficiency. Platooning imposes certain vehicle-to-vehicle considerations, most of these are applicable to both UAVs and other vehicletypes. </t> <t> UAVs/vehiclestypes.</t> <t>UAVs and other vehicles typically have various forms of wireless connectivity: </t><t> <list style="symbols"> <t>Cellular:<ul spacing="normal"> <li>Cellular: for communication with the control center,forremotemaneuvering as well asmaneuvering, and monitoring of thedrone; </t> <t>IEEEdrone;</li> <li>IEEE 802.11: for inter-drone communications (i.e., platooning) and providing connectivity to other devices (i.e., acting as AccessPoint). </t> </list> </t> <t> NotePoint).</li> </ul> <t>Note that autonomous cars share many of the characteristics of theaforementionaforementioned UAVcase, and thereforecase. Therefore, it is of interest for RAW. </t> </section> <sectiontitle="Specifics"> <t> Somenumbered="true" toc="default"> <name>Specifics</name> <t>Some of theuse-cases/tasksuse cases and tasks involving UAVs require coordination among UAVs. Others involve complexcomputecomputing tasks that might not be performed using the limited computing resources that a drone typically has. These two aspects require continuous connectivity with the control center and among UAVs. </t><t> Remote<t>Remote maneuvering of a drone might be performed over a cellular network in some cases,however,but there are situations that need very low latency and deterministic behavior of the connectivity. Examples involve platooning of drones or sharing of computing resources among drones(like,(like a droneoffloadoffloading some function to a neighboring drone). </t> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> UAVsWireless</name> <t>UAVs cannot be connected through any type of wired media, so it is obvious that wireless is needed. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> TheRAW</name> <t>The network infrastructure is composedbyof the UAVs themselves, requiring self-configuration capabilities. </t><t> Heterogeneous<t>Heterogeneous types of traffic need to be supported, from extremely criticalonestraffic types requiring ultra-low latency and highresiliency,resiliency to traffic requiringlow-mediumlow-to-medium latency. </t><t> When<t>When a given service is decomposed into functions--(which are hosted at different UAVs-- chained,and chained), each link connecting two given functions would have a well-defined set of requirements (e.g., latency,bandwidthbandwidth, and jitter) that must be met. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Today'snumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>Today's solutions keep the processing operations that are critical local (i.e., they are not offloaded). Therefore, in thisuse-case,use case, the critical requirement is reliability,andand, only for some platooning and inter-dronecommunicationscommunications, latency is critical. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectiontitle="Edgenumbered="true" toc="default"> <name>Edge Roboticscontrol">Control</name> <sectiontitle="Use-Case Description"> <t> The Edge Roboticsnumbered="true" toc="default"> <name>Use Case Description</name> <t>The edge robotics scenario consists of several robots, deployed in a given area (like a shoppingmall),mall) and inter-connected via an access network to a network edge device or a data center. The robots are connected to the edge so that complex computational activities are not executed locally at the robots but offloaded to the edge. This brings additional flexibility in the type of tasks that the robotsdo, as well as reducingperform, reduces the costs ofrobot manufacturingrobot-manufacturing (due to their lower complexity), andenablingenables complex tasks involving coordination among robots (that can be more easily performed if robots are centrally controlled). </t> <t><!-- FT: search and rescue app -->Simple examples of the use of multiple robots are cleaning, video surveillance (note that this have to comply with local regulations regardinguser'suser privacy at the application level), search and rescue operations, and delivering of goods from warehouses to shops. Multiple robots are simultaneously instructed to perform individual tasks by moving the robotic intelligence from the robots to the network's edge. That enables easy synchronization, scalable solution, and on-demand option to create flexible fleet of robots. </t><t> Robots<t>Robots would have various forms of wireless connectivity: </t><t> <list style="symbols"> <t> IEEE 802.11: for connection to the edge and also inter-robot communications (i.e., for coordinated actions). </t> <t> Cellular:<ul spacing="normal"> <li>Cellular: as an additional communication link to the edge, though primarily as backup, since ultra-low latency is needed.</t> </list> </t></li> <li>IEEE 802.11: for connection to the edge and also inter-robot communications (i.e., for coordinated actions).</li> </ul> </section> <sectiontitle="Specifics"> <t> Somenumbered="true" toc="default"> <name>Specifics</name> <t>Some of theuse-cases/tasksuse cases and tasks involving robots might benefit from decomposition of a serviceininto small functions that are distributed and chained among robots and the edge. These require continuous connectivity with the control center and among drones. </t><t> Robot<t>Robot control is an activity requiring very low latency (0.5-20 ms <xref target="Groshev2021"/>)format="default"/>) between the robot and the location where the control intelligence resides (which might be the edge or another robot). </t> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> DeployingWireless</name> <t>Deploying robots in scenarios such as shopping malls for the applications mentioned cannot be done via wired connectivity. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> TheRAW</name> <t>The network infrastructure needs to support heterogeneous types of traffic, from robot control to video streaming. </t><t> When<t>When a given service is decomposed into functions--(which are hosted at differentrobots -- chained,UAVs and chained), each link connecting two given functions would have a well-defined set of requirements(latency, bandwidth(e.g., latency, bandwidth, and jitter) that must be met. </t> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> This use-casenumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>This use case might combine multiple communication flows, with some of them being latency critical (like those related torobot controlrobot-control tasks). Note that there are still many communication flows (like some offloading tasks) that only demand reliability and availability. </t> </section> <!-- END Non-latency critical considerations --> </section> </section><!-- [2020-07-11] cjbc: text added --><sectiontitle="Instrumented emergency medical vehicles"> <section title="Use-Case Description"> <t>numbered="true" toc="default"> <name>Instrumented Emergency Medical Vehicles</name> <section numbered="true" toc="default"> <name>Use Case Description</name> <!--[rfced] To follow up, should "be" be "have"? Current: An instrumented ambulance would be one or multiple network segments that are connected to end systems such as: Perhaps: An instrumented ambulance would have one or multiple network segmentsto whichthat are connectedtheseto end systems such as:<list style="symbols" >--> <t>vitalAn instrumented ambulance would be one or multiple network segments that are connected to end systems such as:</t> <ul spacing="normal"> <li>vital signs sensors attached to the casualty in theambulance. Relayambulance to relay medical data to hospital emergencyroom, </t> <t>room,</li> <li>a radio-navigation sensor to relay position data to various destinations including dispatcher,</t> <t> voice</li> <li>voice communication for ambulance attendant(like(likely to consult with ER doctor), and</t> <t> voice</li> <li>voice communication between driver and dispatcher.</t> </list> </t> <t> The</li> </ul> <t>The LAN needs to be routed through radio-WANs (a radio network in the interior of a network, i.e., it is terminated by routers) to complete the network linkage. </t> </section> <sectiontitle="Specifics"> <t> Whatnumbered="true" toc="default"> <name>Specifics</name> <t>What we have today is multiple communication systems to reach the vehicle via:<list style="symbols" > <t> A</t> <ul spacing="normal"> <li>a dispatching system,</t> <t> a</li> <li>a cellphone for the attendant,</t> <t> a</li> <li>a special purpose telemetering system for medical data,</t> <t> etc. </t> </list> </t> <t> This</li> <li>etc. </li> </ul> <t>This redundancy of systems does not contribute to availability. </t><t> Most<t>Most of the scenarios involving the use of an instrumented ambulance are composed of many different flows, each of them with slightly different requirements in terms of reliability and latency. Destinations might be eitheratthe ambulance itself (local traffic),ata near edgecloudcloud, oratthe general Internet/cloud. Special care (at application level) have to be paid toensuringensure that sensitive data is not disclosed to unauthorizedparties,parties by properly securing traffic and authenticating the communication ends. </t> </section> <sectiontitle="Thenumbered="true" toc="default"> <name>The Need forWireless"> <t> LocalWireless</name> <t>Local traffic between the firstresponders/ambulanceresponders and ambulance staff and the ambulance equipment cannot be done via wired connectivity as the responders perform initial treatment outside of the ambulance. The communications from the ambulance to external services must be wireless as well. </t> </section> <!-- title="The Need for Wireless" --> <sectiontitle="Requirementsnumbered="true" toc="default"> <name>Requirements forRAW"> <t> WeRAW</name> <t>We can derive some pertinent requirements from this scenario:<list style="symbols" > <t> High</t> <ul spacing="normal"> <li>High availability of theinter-networkinternetwork is required. The exact level of availability depends on the specific deployment scenario, as not all emergency agencies share the same type of instrumented emergency vehicles.</t> <t> The inter-network</li> <li>The internetwork needs to operate in damaged state(e.g.(e.g., during an earthquake aftermath, heavy weather, a wildfire, etc.). In addition to continuity of operations, rapid restore is a needed characteristic.</t> <!-- <t> E2E security, both authenticity and confidentiality, is required of traffic. All data needs to be authenticated; some like medical needs to be confidential. </t> --> <t> The</li> <li>The radio-WAN has characteristics similar tocellphonethe cellphone's -- the vehicle will travel from one radio coverage area to another, thus requiring some hand-off approach.</t> </list> </t></li> </ul> <!-- BEGIN Non-latency critical considerations --> <sectiontitle="Non-latency critical considerations"> <t> Innumbered="true" toc="default"> <name>Non-latency-critical Considerations</name> <t>In this case, all applications identified do not requirelatency critical communication,latency-critical communication but do need high reliability and availability. </t> </section> <!-- END Non-latency critical considerations --> </section> </section> <sectionanchor="sec:summary" title="Summary"> <t> Thisanchor="sec_summary" numbered="true" toc="default"> <name>Summary</name> <t>This document enumerates severaluse-casesuse cases and applications that need RAW technologies, focusing on the requirements from reliability,availabilityavailability, and latency.WhereasWhile someuse-casesuse cases arelatency-critical,latency critical, there are also several applications that arenon-latency critical,not latency critical butthatdo pose strict reliability and availability requirements. </t> </section> <sectionanchor="sec:iana" title="IANA Considerations"> <t> Thisanchor="sec_iana" numbered="true" toc="default"> <name>IANA Considerations</name> <t>This document has no IANA actions. </t> </section> <sectionanchor="sec:security" title="Security Considerations"> <t> Thisanchor="sec_security" numbered="true" toc="default"> <name>Security Considerations</name> <t>This document covers several representative applications and network scenarios that are expected to make use of RAW technologies. Each of the potential RAWuse-casesuse cases will have security considerations from both the use-specific perspective and the RAW technology perspective. <xref target="RFC9055"/>format="default"/> provides a comprehensive discussion of security considerations in the context ofdeterministic networking,DetNet, which are generallyapplicablealso applicable to RAW. </t> </section><section anchor="sec:acks" title="Acknowledgments"> <t> Nils Mäurer, Thomas Gräupl and Corinna Schmitt have contributed significantly</middle> <back> <displayreference target="I-D.ietf-raw-industrial-requirements" to="RAW-IND-REQS"/> <displayreference target="I-D.ietf-6tisch-terminology" to="6TiSCH-TERMS"/> <displayreference target="I-D.ietf-raw-technologies" to="RAW-TECHNOS"/> <references> <name>Informative References</name> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2475.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7554.xml"/> <!-- 6TiSCH TSCH --> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8557.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8578.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8655.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9030.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9055.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9372.xml"/> <!-- [I-D.ietf-raw-industrial-requirements] IESG state Expired --> <xi:include href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-raw-industrial-requirements.xml"/> <!-- [I-D.ietf-6tisch-terminology] IESG state Expired. Updated tothis document, providing inputlong version because missing editor role for Palattella --> <reference anchor="I-D.ietf-6tisch-terminology" target="https://datatracker.ietf.org/doc/html/draft-ietf-6tisch-terminology-10"> <front> <title>Terms Used in IPv6 over theAeronautical communication section. Rex Buddenberg has also contributed to the document, providing input to the Emergency: instrumented emergency vehicle section. </t> <t> The authors would like to thank Toerless Eckert, Xavi Vilajosana Guillen, Rute Sofia, Corinna Schmitt, Victoria Pritchard, John Scudder, Joerg Ott and Stewart Bryant for their valuable comments on previous versionsTSCH mode ofthis document. </t> <t> The workIEEE 802.15.4e</title> <author initials="MR." surname="Palattella" fullname="Maria Rita Palattella" role="editor"> <organization>LIST</organization> </author> <author initials="P." surname="Thubert" fullname="Pascal Thubert"> <organization>cisco</organization> </author> <author initials="T." surname="Watteyne" fullname="Thomas Watteyne"> <organization>Analog Devices</organization> </author> <author initials="Q." surname="Wang" fullname="Qin Wang"> <organization>Univ. ofCarlos J. Bernardos in this document has been partially supported by the Horizon Europe PREDICT-6G (Grant 101095890)Sci. andUNICO I+D 6G-DATADRIVEN-04 project. </t> </section> </middle> <back> <!-- <references title="Normative References"> </references> --> <references title="Informative References"> <?rfc include="reference.RFC.7554"?>Tech. Beijing</organization> </author> <date month="March" day="2" year="2018"/> </front> <seriesInfo name="Internet-Draft" value="draft-ietf-6tisch-terminology-10"/> </reference> <!--6TiSCH TSCH[I-D.ietf-raw-technologies] IESG state I-D Exists. Updated to long version because missing editor role for Thubert --><?rfc include='reference.RFC.8557'?> <?rfc include='reference.RFC.8578'?> <?rfc include='reference.RFC.8655'?> <?rfc include='reference.RFC.9030'?> <?rfc include='reference.RFC.9055'?> <?rfc include='reference.I-D.ietf-raw-ldacs'?> <?rfc include='reference.I-D.ietf-raw-industrial-requirements'?> <?rfc include='reference.I-D.ietf-6tisch-terminology'?> <?rfc include='reference.I-D.ietf-raw-technologies'?> <?rfc include='reference.RFC.9317'?> <?rfc include='reference.RFC.9372'?><reference anchor="I-D.ietf-raw-technologies" target="https://datatracker.ietf.org/doc/html/draft-ietf-raw-technologies-06"> <front> <title>Reliable and Available Wireless Technologies</title> <author initials="P." surname="Thubert" fullname="Pascal Thubert" role="editor"> <organization>Cisco Systems, Inc</organization> </author> <author initials="D." surname="Cavalcanti" fullname="Dave Cavalcanti"> <organization>Intel Corporation</organization> </author> <author initials="X." surname="Vilajosana" fullname="Xavier Vilajosana"> <organization>Universitat Oberta de Catalunya</organization> </author> <author initials="C." surname="Schmitt" fullname="Corinna Schmitt"> <organization>Research Institute CODE, UniBw M</organization> </author> <author initials="J." surname="Farkas" fullname="János Farkas"> <organization>Ericsson</organization> </author> <date month="November" day="30" year="2022"/> </front> <seriesInfo name="Internet-Draft" value="draft-ietf-raw-technologies-06"/> </reference> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9317.xml"/> <reference anchor="DISNEY15" target="https://www.wired.com/2015/03/disney-magicband/"> <front> <title>Disney's $1 Billion Bet on a Magical Wristband</title><author><author surname="Kuang" initials="C."> <organization>Wired</organization> </author> <date year="2015" month="March"/> </front> </reference> <referenceanchor="KEAV20"anchor="SESAR" target="https://www.sesarju.eu/"><!--LDACS--><front><title>Single European Sky ATM Research<title>SESAR Joint Undertaking</title> <author><organization>T. Keaveney and C. Stewart</organization><organization>SESAR</organization> </author><date year="2019"/></front> </reference> <reference anchor="FAA20"target="https://www.faa.gov/nextgen/ ">target="https://www.faa.gov/nextgen/"> <!--LDACS--> <front> <title>Next Generation Air TransportationSystem</title>System (NextGen)</title> <author> <organization>U.S. Department ofTransportationTransportation: Federal Aviation Administration (FAA)</organization> </author><date year="2019"/></front> </reference> <reference anchor="PLA14"> <!--LDACS--> <front> <title>Flight Trial Demonstration of Seamless AeronauticalNetworking </title>Networking</title> <author initials="S." surname="Plass"/> <author initials="R." surname="Hermenier"/> <author initials="O."surname="Luecke"/>surname="Lücke"/> <author initials="D." surname="Gomez Depoorter"/> <author initials="T." surname="Tordjman"/> <author initials="M." surname="Chatterton"/> <author initials="M." surname="Amirfeiz"/> <author initials="S." surname="Scotti"/> <authorinitials="Y.J."initials="Y." surname="Cheng"/> <author initials="P." surname="Pillai"/> <author initials="T."surname="Graeupl"/>surname="Gräupl"/> <author initials="F." surname="Durand"/> <author initials="K." surname="Murphy"/> <author initials="A." surname="Marriott"/> <author initials="A." surname="Zaytsev"/> <date year="2014" month="May"/> </front> <seriesInfoname='IEEEname="DOI" value="10.1109/MCOM.2014.6815902"/> <refcontent>IEEE Communications Magazine,vol.Volume 52,no. 5' value=''/>Issue 5</refcontent> </reference> <referenceanchor="ICAO18"> <!--LDACS-->anchor="ICAO2022" target="https://www.ldacs.com/wp-content/uploads/2023/03/WP06.AppA-DCIWG-6-LDACS_SARPs.pdf"> <front><title>L-Band<title>CHAPTER 13 L-Band Digital AeronauticalCommunicationCommunications System(LDACS) </title>(LDACS)</title> <author initials=""surname="Internationalsurname=""> <organization>International Civil Aviation Organization(ICAO)"/>(ICAO)</organization> </author> <dateyear="2018"/>year="2022"/> </front><seriesInfo name='International<refcontent>International Standards and RecommendedPracticesPractices, Annex 10 - Aeronautical Telecommunications,Vol. III -Volume III, CommunicationSystems' value=''/> </reference> <reference anchor="IEEE80211-RT-TIG" target="http://www.ieee802.org/11/Reports/rtatig_update.htm"> <front> <title>IEEE 802.11 Real Time Applications TIG Report</title> <author> <organization>IEEE</organization> </author> <date year="2018" month="November"/> </front>Systems</refcontent> </reference> <referenceanchor="KOB12" target="https://doi.org/10.1109/HUMANOIDS.2012.6651623">anchor="KOB12"> <front> <title>Playing catch and juggling with a humanoidrobot.</title>robot</title> <author initials="J."surname="Kober" fullname="J. Kober"></author>surname="Kober"/> <author initials="M."surname="Glisson" fullname="M. Glisson"></author>surname="Glisson"/> <author initials="M."surname="Mistry" fullname="M. Mistry"></author>surname="Mistry"/> <date month="November" year="2012"/> </front> <seriesInfo name="DOI" value="10.1109/HUMANOIDS.2012.6651623"/> </reference> <referenceanchor="ODVA">anchor="ODVA" target="https://www.odva.org/"> <front><title>The organization that supports network technologies built on the Common<title>ODVA | IndustrialProtocol (CIP) including EtherNet/IP.</title>Automation | Technologies and Standards</title> <author><organization>http://www.odva.org/</organization><organization>ODVA</organization> </author><date></date><date/> </front> </reference> <reference anchor="PROFINET"target="http://us.profinet.com/technology/profinet/">target="https://us.profinet.com/technology/profinet/"> <front> <title>PROFINETis a standard for industrial networking in automation. </title>Technology</title> <author><organization>http://us.profinet.com/technology/profinet/</organization><organization>PROFINET</organization> </author><date></date><date/> </front> </reference> <reference anchor="EIP"target="http://www.odva.org/Portals/0/Library/Publications_Numbered/PUB00138R3_CIP_Adv_Tech_Series_EtherNetIP.pdf">target="https://www.odva.org/technology-standards/key-technologies/ethernet-ip/"> <front><title> EtherNet/IP provides users with the network tools to deploy standard Ethernet technology (IEEE 802.3 combined with the TCP/IP Suite) for industrial automation applications while enabling Internet and enterprise connectivity data anytime, anywhere.</title><title>EtherNet/IP | ODVA Technologies | Industrial Automation</title> <author><organization>http://www.odva.org/</organization><organization>ODVA</organization> </author><date></date><date/> </front> </reference> <reference anchor="ISA100" target="https://www.isa.org/isa100/"> <front> <title>ISA100, Wireless Systems for Automation</title> <author><organization>ISA/ANSI</organization><organization>ISA</organization> </author> <date/> </front> </reference> <reference anchor="ACI19" target="https://store.aci.aero/product/annual-world-airport-traffic-report-2019/"> <front> <title>Annual WorldAitportAirport TrafficReportReport, 2019</title> <author> <organization>Airports CouncilInternational (ACI)</organization>International</organization> </author> <dateyear="2019" month="November"/>year="2019"/> </front> </reference> <reference anchor="IAT20" target="https://www.iata.org/en/iata-repository/publications/economic-reports/airline-industry-economic-performance---november-2020---report/"> <front> <title>Economic Performance of the Airline Industry</title> <author><organization>International Air Transport Association (IATA)</organization><organization>IATA</organization> </author> <date year="2020" month="November"/> </front> </reference> <reference anchor="IAC20"> <front> <title>Estimating and projecting air passenger traffic during the COVID-19 coronavirus outbreak and itssocio- economic impact </title>socio-economic impact</title> <authorinitials="S.M."initials="S." surname="Iacus"/> <author initials="F." surname="Natale"/> <author initials="C." surname="Santamaria"/> <author initials="S." surname="Spyratos"/> <authorinitials="V." surname="Michele"/>initials="M." surname="Vespe"/> <dateyear="2020" />month="September" year="2020"/> </front> <seriesInfoname='Safety Science 129 (2020) 104791' value=''/>name="DOI" value="10.1016/j.ssci.2020.104791"/> <refcontent>Safety Science, Volume 129</refcontent> </reference> <referenceanchor="IEEE802.1TSN">anchor="IEEE802.1AS"> <front> <title>IEEE802.1AS-2011 - IEEEStandard for Local and Metropolitan AreaNetworks - TimingNetworks--Timing and Synchronization for Time-SensitiveApplications in Bridged Local Area Networks </title>Applications</title> <author><organization>IEEE standard for Information Technology</organization><organization>IEEE</organization> </author><date/><date month="June" year="2020"/> </front> <seriesInfo name="DOI" value="10.1109/IEEESTD.2020.9121845"/> <seriesInfo name="IEEE" value="802.1AS-2020"/> </reference> <reference anchor="IEEE80211BE" target="https://www.ieee802.org/1/files/public/docs2020/new-Cavalcanti-802-1TSN-over-802-11-1120-v02.pdf"> <front> <title>802.1 TSN over 802.11 with updates from developments in 802.11be </title> <author initials="D."surname="Cavalcanti" fullname="D. Cavalcanti"></author>surname="Cavalcanti"/> <author initials="G."surname="Venkatesan" fullname="G. Venkatesan"></author>surname="Venkatesan"/> <date year="2020"month="November" />month="November"/> </front><seriesInfo name='IEEE<refcontent>IEEE plenarymeeting' value=''/>meeting</refcontent> </reference> <reference anchor="IEEE80211RTA"> <front> <title>IEEE 802.11 Real Time Applications TIG Report </title> <author> <organization>IEEE standard for Information Technology</organization> </author> <date year="2018"month="November" />month="November"/> </front> </reference> <referenceanchor="MAR19" target="https://ieeexplore.ieee.org/document/8703476">anchor="MAR19"> <front> <title>A Square Peg in a Round Hole: The Complex Path for Wireless in the Manufacturing Industry</title> <author initials="B."surname="Martinez" fullname="B. Martinez"></author>surname="Martinez"/> <author initials="C."surname="Cano" fullname="C. Cano"></author>surname="Cano"/> <author initials="X."surname="Vilajosana" fullname="X. Vilajosana"></author>surname="Vilajosana"/> <date month="April" year="2019"/> </front> <seriesInfo name="DOI" value="10.1109/MCOM.2019.1800570"/> <refcontent>IEEE Communications Magazine, Volume 57, Issue 4</refcontent> </reference> <reference quoteTitle="false" anchor="DGT2021" target="https://revista.dgt.es/es/reportajes/2021/01ENERO/0126-Como-funciona-un-operativo-con-drones.shtml"> <front><title>Drones: asi<title>"Drones: así es lavigilancia</title>vigilancia" [Drones: this is surveillance]</title> <authorinitials="J. M." surname="Menendez" fullname="J. M. Menendez"></author>initials="J." surname="Menéndez"/> <date month="January" year="2021"/> </front> </reference> <referenceanchor="Groshev2021" target="https://doi.org/10.1109/ACCESS.2021.3098109">anchor="Groshev2021"> <front> <title>Dissecting the Impact of Information and Communication Technologies on Digital Twins as a Service</title> <author initials="M."surname="Groshev" fullname="M. Groshev"></author>surname="Groshev"/> <author initials="C."surname="Guimaraes" fullname="C. Guimaraes"></author>surname="Guimarães"/> <author initials="A." surname="de laOliva" fullname="A. de la Oliva"></author>Oliva"/> <authorinitials="B." surname="Gazda" fullname="B. Gazda"></author>initials="R." surname="Gazda"/> <date month="July" year="2021"/> </front> <seriesInfoname='IEEEname="DOI" value="10.1109/ACCESS.2021.3098109"/> <refcontent>IEEE Access,vol. 9' value=''/>Volume 9</refcontent> </reference> <referenceanchor="Maurer2022" target="https://doi.org/10.1016/j.ijcip.2022.100549">anchor="Maurer2022"> <front> <title>Security in Digital Aeronautical Communications A Comprehensive Gap Analysis</title> <author initials="N."surname="Maurer" fullname="N. Maurer"></author>surname="Mäurer"/> <author initials="T."surname="Ewert" fullname="T. Ewert"></author>surname="Guggemos"/> <author initials="T."surname="Graupl" fullname="T. Graupl"></author>surname="Ewert"/> <author initials="T." surname="Gräupl"/> <author initials="C."surname="Schmitt" fullname="C. Schmitt"></author>surname="Schmitt"/> <author initials="S."surname="Grundner-Culemann" fullname="S. Grundner-Culemann"></author>surname="Grundner-Culemann"/> <date month="September" year="2022"/> </front> <seriesInfoname='Internationalname="DOI" value="10.1016/j.ijcip.2022.100549"/> <refcontent>International Journal of Critical Infrastructure Protection,vol. 38' value=''/>Volume 38</refcontent> </reference> <reference anchor="ARINC858P1" target="https://www.sae.org/standards/content/arinc858p1/"> <front><title>INTERNET PROTOCOL SUITE<title>Internet Protocol Suite (IPS)FOR AERONAUTICAL SAFETY SERVICES PARTfor Aeronautical Safety Services Part 1AIRBORNEAirborne IPSSYSTEM TECHNICAL REQUIREMENTS</title>System Technical Requirements</title> <author><organization>ARINC</organization><organization>SAE International</organization> </author> <date month="June" year="2021"/> </front> <refcontent>ARINC858P1</refcontent> </reference> </references> <section anchor="sec_acks" numbered="false" toc="default"> <name>Acknowledgments</name> <t><contact fullname="Nils Mäurer"/>, <contact fullname="Thomas Gräupl"/>, and <contact fullname="Corinna Schmitt"/> have contributed significantly to this document, providing input for the Aeronautical communication section. <contact fullname="Rex Buddenberg"/> has also contributed to the document, providing input to the "Instrumented Emergency Medical Vehicles" section.</t> <t>The authors would like to thank <contact fullname="Toerless Eckert"/>, <contact fullname="Xavi Vilajosana Guillen"/>, <contact fullname="Rute Sofia"/>, <contact fullname="Corinna Schmitt"/>, <contact fullname="Victoria Pritchard"/>, <contact fullname="John Scudder"/>, <contact fullname="Joerg Ott"/>, and <contact fullname="Stewart Bryant"/> for their valuable comments on draft versions of this document.</t> <t>The work of <contact fullname="Carlos J. Bernardos"/> in this document has been partially supported by the Horizon Europe PREDICT-6G (Grant 101095890) and UNICO I+D 6G-DATADRIVEN-04 project.</t> </section> </back> </rfc>