rfc9912v1.txt   rfc9912.txt 
Internet Engineering Task Force (IETF) P. Thubert, Ed. Internet Engineering Task Force (IETF) P. Thubert, Ed.
Request for Comments: 9912 February 2026 Request for Comments: 9912 Independent
Category: Informational Category: Informational February 2026
ISSN: 2070-1721 ISSN: 2070-1721
Reliable and Available Wireless (RAW) Architecture Reliable and Available Wireless (RAW) Architecture
Abstract Abstract
Reliable and Available Wireless (RAW) extends the reliability and Reliable and Available Wireless (RAW) extends the reliability and
availability of Deterministic Networking (DetNet) to networks availability of Deterministic Networking (DetNet) to networks
composed of any combination of wired and wireless segments. The RAW composed of any combination of wired and wireless segments. The RAW
architecture leverages and extends RFC 8655 ("Deterministic architecture leverages and extends RFC 8655 ("Deterministic
skipping to change at line 210 skipping to change at line 210
RAW is agnostic to the lower layer, though the capability to control RAW is agnostic to the lower layer, though the capability to control
latency is assumed to ensure the DetNet services that RAW extends. latency is assumed to ensure the DetNet services that RAW extends.
How the lower layers are operated to do so (and whether a radio How the lower layers are operated to do so (and whether a radio
network is single hop or meshed, for example) are opaque to the IP network is single hop or meshed, for example) are opaque to the IP
layer and not part of the RAW abstraction. Nevertheless, cross-layer layer and not part of the RAW abstraction. Nevertheless, cross-layer
optimizations may take place to ensure proper link awareness (such as optimizations may take place to ensure proper link awareness (such as
link quality) and packet handling (such as scheduling). link quality) and packet handling (such as scheduling).
The RAW architecture extends the DetNet Network Plane to accommodate The RAW architecture extends the DetNet Network Plane to accommodate
one or multiple hops of homogeneous or heterogeneous wired and one or multiple hops of homogeneous or heterogeneous wired and
wireless technologies. RAW adds reactivity to the DetNet Forwarding wireless technologies. RAW adds reactivity to the DetNet forwarding
sub-layer to compensate the dynamics for the radio links in terms of sub-layer to compensate the dynamics for the radio links in terms of
lossiness and bandwidth. This may apply, for instance, to mesh lossiness and bandwidth. This may apply, for instance, to mesh
networks as illustrated in Figure 4 or diverse radio access networks networks as illustrated in Figure 4 or diverse radio access networks
as illustrated in Figure 10. as illustrated in Figure 10.
As opposed to wired links, the availability and performance of an As opposed to wired links, the availability and performance of an
individual wireless link cannot be trusted over the long term; it individual wireless link cannot be trusted over the long term; it
varies with transient service discontinuity, and any path that varies with transient service discontinuity, and any path that
includes wireless hops is bound to face short periods of high loss. includes wireless hops is bound to face short periods of high loss.
On the other hand, being broadcast in nature, the wireless medium On the other hand, being broadcast in nature, the wireless medium
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1. a new and more dynamic sense of link metrics, with new 1. a new and more dynamic sense of link metrics, with new
protocols such as the Dynamic Link Exchange Protocol (DLEP) protocols such as the Dynamic Link Exchange Protocol (DLEP)
and Layer 2 (L2) triggers to keep Layer 3 (L3) up to date with and Layer 2 (L2) triggers to keep Layer 3 (L3) up to date with
the link quality and availability, and the link quality and availability, and
2. an approach to multipath routing, where multiple link metrics 2. an approach to multipath routing, where multiple link metrics
are considered since simple shortest-path cost loses its are considered since simple shortest-path cost loses its
meaning with the instability of the metrics. meaning with the instability of the metrics.
Redundant transmissions: Though feasible on any technology, Redundant transmissions: Though feasible on any technology,
proactive (forward) and reactive (ack-based) error correction are proactive (forward) and reactive (acknowledgment-based) error
typical for wireless media. Bounded latency can still be obtained correction is typical for wireless media. Bounded latency can
on a wireless link while operating those technologies, provided still be obtained on a wireless link while operating those
that link latency used in path selection allows for the extra technologies, provided that link latency used in path selection
transmission or the introduced delay is compensated along the allows for the extra transmission or the introduced delay is
path. In the case of coded fragments and retries, it makes sense compensated along the path. In the case of coded fragments and
to vary all the possible physical properties of the transmission retries, it makes sense to vary all the possible physical
to reduce the chances that the same effect causes the loss of both properties of the transmission to reduce the chances that the same
original and redundant transmissions. effect causes the loss of both original and redundant
transmissions.
Relay coordination and constructive interference: Though it can be Relay coordination and constructive interference: Though it can be
difficult to achieve at high speed, a fine time synchronization difficult to achieve at high speed, a fine time synchronization
and a precise sense of phase allows the energy from multiple and a precise sense of phase allows the energy from multiple
coordinated senders to add up at the receiver and actually improve coordinated senders to add up at the receiver and actually improve
the signal quality, compensating for either distance or physical the signal quality, compensating for either distance or physical
objects in the Fresnel zone that would reduce the link budget. objects in the Fresnel zone that would reduce the link budget.
From a DetNet perspective, this may translate taking into account From a DetNet perspective, this may translate to taking into
how transmission from one node may interfere with the transmission account how transmission from one node may interfere with the
of another node attached to the same wireless sub-layer network. transmission of another node attached to the same wireless sub-
layer network.
RAW and DetNet enable application flows that require a special RAW and DetNet enable application flows that require a special
treatment along paths that can provide that treatment. This may be treatment along paths that can provide that treatment. This may be
seen as a form of Path Aware networking and may be subject to seen as a form of Path Aware networking and may be subject to
impediments documented in [RFC9049]. impediments documented in [RFC9049].
The mechanism used to establish a path is not unique to, or The mechanism used to establish a path is not unique to, or
necessarily impacted by, RAW. It is expected to be the product of necessarily impacted by, RAW. The mechanism is expected to be the
the DetNet Controller Plane [DetNet-PLANE]; it may use a Path product of the DetNet Controller Plane [DetNet-PLANE]; it may use a
Computation Element (PCE) [RFC4655] or the DetNet YANG data model Path Computation Element (PCE) [RFC4655] or the DetNet YANG data
[RFC9633], or it may be computed in a distributed fashion ala the model [RFC9633], or it may be computed in a distributed fashion as
Resource ReSerVation Protocol (RSVP) [RFC2205]. Either way, the per the Resource ReSerVation Protocol (RSVP) [RFC2205]. Either way,
assumption is that it is slow relative to local forwarding operations the assumption is that it is slow relative to local forwarding
along the path. To react fast enough to transient changes in the operations along the path. To react fast enough to transient changes
radio transmissions, RAW leverages DetNet Network Plane enhancements in the radio transmissions, RAW leverages DetNet Network Plane
to optimize the use of the paths and match the quality of the enhancements to optimize the use of the paths and match the quality
transmissions over time. of the transmissions over time.
As opposed to wired networks, the action of installing a path over a As opposed to wired networks, the action of installing a path over a
set of wireless links may be very slow relative to the speed at which set of wireless links may be very slow relative to the speed at which
the radio conditions vary; thus, in the wireless case, it makes sense the radio conditions vary; thus, in the wireless case, it makes sense
to provide redundant forwarding solutions along alternate paths (see to provide redundant forwarding solutions along alternate paths (see
Section 3.3) and to leave it to the Network Plane to select which of Section 3.3) and to leave it to the Network Plane to select which of
those forwarding solutions are to be used for a given packet based on those forwarding solutions are to be used for a given packet based on
the current conditions. The RAW Network Plane operations happen the current conditions. The RAW Network Plane operations happen
within the scope of a recovery graph (see Section 3.3.2) that is pre- within the scope of a recovery graph (see Section 3.3.2) that is pre-
established and installed by means outside of the scope of RAW. A established and installed by means outside of the scope of RAW. A
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entirety of the flows or a portion of them, the RAW Network Plane entirety of the flows or a portion of them, the RAW Network Plane
operations may affect the metrics used in their rerouting decisions, operations may affect the metrics used in their rerouting decisions,
which could potentially lead to oscillations; such effects must be which could potentially lead to oscillations; such effects must be
avoided or dampened. avoided or dampened.
3. Terminology 3. Terminology
RAW reuses terminology defined for DetNet in "Deterministic RAW reuses terminology defined for DetNet in "Deterministic
Networking Architecture" [DetNet-ARCHI], e.g., "PREOF" to stand for Networking Architecture" [DetNet-ARCHI], e.g., "PREOF" to stand for
"Packet Replication, Elimination, and Ordering Functions". RAW "Packet Replication, Elimination, and Ordering Functions". RAW
inherits and augments the IETF art of protection as seen in DetNet inherits and augments the IETF art of path protection as seen in
and Traffic Engineering. DetNet and Traffic Engineering.
RAW also reuses terminology defined for Operations, Administration, RAW also reuses terminology defined for Operations, Administration,
and Maintenance (OAM) protocols in Section 1.1 of "Framework of and Maintenance (OAM) protocols in Section 1.1 of "Framework of
Operations, Administration, and Maintenance (OAM) for Deterministic Operations, Administration, and Maintenance (OAM) for Deterministic
Networking (DetNet)" [DetNet-OAM] and in "Active and Passive Metrics Networking (DetNet)" [DetNet-OAM] and in "Active and Passive Metrics
and Methods (with Hybrid Types In-Between)" [RFC7799]. and Methods (with Hybrid Types In-Between)" [RFC7799].
RAW also reuses terminology defined for MPLS in [RFC4427], such as RAW also reuses terminology defined for MPLS in [RFC4427], such as
the term "recovery" to cover both protection and restoration for a the term "recovery" to cover both protection and restoration for a
number of recovery types. That document defines a number of number of recovery types. That document defines a number of
concepts, such as the recovery domain, that are used in RAW concepts, such as the recovery domain, that are used in RAW
mechanisms and defines the new term "recovery graph". A recovery mechanisms and defines the new term "recovery graph". A recovery
graph associates a topological graph with usage metadata that graph associates a topological graph with usage metadata that
represents how the paths are built and used within the recovery represents how the paths are built and used within the recovery
graph. The recovery graph provides excess bandwidth for the intended graph. The recovery graph provides excess bandwidth for the intended
traffic over alternate potential paths, and the use of that bandwidth traffic over alternate potential paths, and the use of that bandwidth
is optimized dynamically. is optimized dynamically.
The concept of a recovery graph is agnostic to the underlying
technology and applies, but is not limited to, any full or partial
wireless mesh. RAW specifies strict and loose recovery graphs
depending on whether the path is fully controlled by RAW or traverses
an opaque network where RAW cannot observe and control the individual
hops.
RAW also reuses terminology defined for RSVP-TE in [RFC4090], such as RAW also reuses terminology defined for RSVP-TE in [RFC4090], such as
the "Point of Local Repair (PLR)". The concept of a backup path is the "Point of Local Repair (PLR)". The concept of a backup path is
generalized with protection path, which is the term mostly found in generalized with protection path, which is the term mostly found in
recent standards and used in this document. recent standards and used in this document.
RAW also reuses terminology defined for 6TiSCH in [6TiSCH-ARCHI] and RAW also reuses terminology defined for 6TiSCH in [6TiSCH-ARCHI] and
equates the 6TiSCH concept of a Track with that of a recovery graph. equates the 6TiSCH concept of a Track with that of a recovery graph.
The concept of a recovery graph is agnostic to the underlying
technology and applies, but is not limited to, any full or partial
wireless mesh. RAW specifies strict and loose recovery graphs
depending on whether the path is fully controlled by RAW or traverses
an opaque network where RAW cannot observe and control the individual
hops.
3.1. Abbreviations 3.1. Abbreviations
RAW uses the following abbreviations. RAW uses the following abbreviations.
3.1.1. ARQ 3.1.1. ARQ
Automatic Repeat Request. A well-known mechanism that enables an Automatic Repeat Request. A well-known mechanism that enables an
acknowledged transmission with retries to mitigate errors and loss. acknowledged transmission with retries to mitigate errors and loss.
ARQ may be implemented at various layers in a network. ARQ is ARQ may be implemented at various layers in a network. ARQ is
typically implemented per hop (not end to end) at Layer 2 in wireless typically implemented per hop (not end to end) at Layer 2 in wireless
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The RF power can come from any source: other transmitters using the The RF power can come from any source: other transmitters using the
same technology, other radio technology using the same band, or same technology, other radio technology using the same band, or
background radiation. For a single hop, RSSI may be used for LQI. background radiation. For a single hop, RSSI may be used for LQI.
3.1.9. LQI 3.1.9. LQI
Link Quality Indicator. An indication of the quality of the data Link Quality Indicator. An indication of the quality of the data
packets received by the receiver. It is typically derived from packets received by the receiver. It is typically derived from
packet error statistics, with the exact method depending on the packet error statistics, with the exact method depending on the
network stack being used. LQI values may be exposed to the network stack being used. LQI values may be exposed to the
controller plane for each individual hop or cumulated along segments. Controller Plane for each individual hop or cumulated along segments.
Outgoing LQI values can be calculated from coherent (demodulated) Outgoing LQI values can be calculated from coherent (demodulated)
PER, RSSI, and incoming LQI values. PER, RSSI, and incoming LQI values.
3.1.10. OAM 3.1.10. OAM
Operations, Administration, and Maintenance. Covers the processes, Operations, Administration, and Maintenance. Covers the processes,
activities, tools, and standards involved with operating, activities, tools, and standards involved with operating,
administering, managing, and maintaining any system. This document administering, managing, and maintaining any system. This document
uses the term in conformance with "Guidelines for the Use of the uses the term in conformance with "Guidelines for the Use of the
'OAM' Acronym in the IETF" [RFC6291], and the system observed by the 'OAM' Acronym in the IETF" [RFC6291], and the system observed by the
RAW OAM is the recovery graph. RAW OAM is the recovery graph.
3.1.11. OODA 3.1.11. OODA
Observe, Orient, Decide, Act. A generic formalism to represent the Observe, Orient, Decide, Act. A generic formalism to represent the
operational steps in a Control Loop. In the context of RAW, OODA is operational steps in a control loop. In the context of RAW, OODA is
applied to network control and convergence; see Section 6.2 for more. applied to network control and convergence; see Section 6.2 for more.
3.1.12. SNR 3.1.12. SNR
Signal-to-Noise Ratio. Also known as "S/N Ratio". A measure used in Signal-to-Noise Ratio. Also known as "S/N Ratio". A measure used in
science and engineering that compares the level of a desired signal science and engineering that compares the level of a desired signal
to the level of background noise. SNR is defined as the ratio of to the level of background noise. SNR is defined as the ratio of
signal power to noise power, often expressed in decibels. signal power to noise power, often expressed in decibels.
3.2. Link and Direction 3.2. Link and Direction
This document uses the following terms relating to links and
direction in the context of RAW.
3.2.1. Flapping 3.2.1. Flapping
In the context of RAW, a link flaps when the reliability of the In the context of RAW, a link flaps when the reliability of the
wireless connectivity drops abruptly for a short period of time, wireless connectivity drops abruptly for a short period of time,
typically a duration of a subsecond to seconds. typically a duration of a subsecond to seconds.
3.2.2. Uplink 3.2.2. Uplink
An uplink is the connection from end devices to data communication An uplink is the connection from end devices to data communication
equipment. In the context of wireless, uplink refers to the equipment. In the context of wireless, uplink refers to the
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Downstream refers to the following the direction of the flow data Downstream refers to the following the direction of the flow data
path along a recovery graph. path along a recovery graph.
3.2.5. Upstream 3.2.5. Upstream
Upstream refers to going against the direction of the flow data path Upstream refers to going against the direction of the flow data path
along a recovery graph. along a recovery graph.
3.3. Path and Recovery Graphs 3.3. Path and Recovery Graphs
This document uses the following terms relating to paths and recovery
graphs in the context of RAW.
3.3.1. Path 3.3.1. Path
Section 1.3.3 of [INT-ARCHI] provides a definition of Path: Section 1.3.3 of [INT-ARCHI] provides a definition of path:
| At a given moment, all the IP datagrams from a particular source | At a given moment, all the IP datagrams from a particular source
| host to a particular destination host will typically traverse the | host to a particular destination host will typically traverse the
| same sequence of gateways. We use the term "path" for this | same sequence of gateways. We use the term "path" for this
| sequence. Note that a path is uni-directional; it is not unusual | sequence. Note that a path is uni-directional; it is not unusual
| to have different paths in the two directions between a given host | to have different paths in the two directions between a given host
| pair. | pair.
Section 2 of [RFC9473] points to a longer, more modern definition of Section 2 of [RFC9473] points to a longer, more modern definition of
path, which begins as follows: path, which begins as follows:
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covers the overall topology where the possible DetNet paths are all covers the overall topology where the possible DetNet paths are all
contained. As such, the recovery graph coalesces all the possible contained. As such, the recovery graph coalesces all the possible
paths a flow may experience, each with its own statistical paths a flow may experience, each with its own statistical
probability to be used. probability to be used.
3.3.2. Recovery Graph 3.3.2. Recovery Graph
A recovery graph is a networking graph that can be followed to A recovery graph is a networking graph that can be followed to
transport packets with equivalent treatment and is associated with transport packets with equivalent treatment and is associated with
usage metadata. In contrast to the definition of a path above, a usage metadata. In contrast to the definition of a path above, a
recovery graph represents not an actual but a potential, is not recovery graph represents a potential path, not an actual one. Also,
necessarily a linear sequence like a simple path, and is not a recovery graph is not necessarily a linear sequence like a simple
necessarily fully traversed (flooded) by all packets of a flow like a path and is not necessarily fully traversed (flooded) by all packets
DetNet Path. Still, and as a simplification, the casual reader may of a flow like a DetNet path. Still, and as a simplification, the
consider that a recovery graph is very much like a DetNet path, casual reader may consider that a recovery graph is very much like a
aggregating multiple paths that may overlap or fork and then rejoin, DetNet path, aggregating multiple paths that may overlap or fork and
for instance, to enable a protection service by the PREOF operations. then rejoin, for instance, to enable a protection service by the
PREOF operations.
_________ _________
| | | |
| IoT G/W | | IoT G/W |
|_________| |_________|
EGRESS <<=== Elimination at Egress EGRESS <<=== Elimination at Egress
| | | |
---+--------+--+--------+-------- ---+--------+--+--------+--------
| Backbone | | Backbone |
__|__ __|__ __|__ __|__
| | Backbone | | Backbone | | Backbone | | Backbone
|__ __| Router |__ __| Router |__ __| Router |__ __| Router
| # | | # |
# \ # / <-- protection path # \ # / <-- protection path
# # #-------# # # #-------#
\ # / # ( Low-power ) \ # / # ( Low-power )
# # \ / # ( Lossy Network) # # \ / # ( Lossy Network)
\ / \ /
# INGRESS <<=== Replication at recovery graph Ingress # INGRESS <<=== Replication at recovery graph ingress
| |
# <-- source device # <-- source device
#: Low-power device #: Low-power device
Figure 1: Example IoT Recovery Graph to an IoT Gateway with 1+1 Figure 1: Example IoT Recovery Graph to an IoT Gateway with 1+1
Redundancy Redundancy
Refining further, a recovery graph is defined as the coalescence of Refining further, a recovery graph is defined as the coalescence of
the collection of all the feasible DetNet Paths that a packet for all the feasible DetNet paths that a packet with an assigned flow may
which a flow is assigned to the recovery graph may be forwarded be forwarded along. A packet that is assigned to the recovery graph
along. A packet that is assigned to the recovery graph experiences experiences one of the feasible DetNet paths based on the current
one of the feasible DetNet Paths based on the current selection by selection by the PLR at the time the packet traverses the network.
the PLR at the time the packet traverses the network.
Refining even further, the feasible DetNet Paths within the recovery Refining even further, the feasible DetNet paths within the recovery
graph may or may not be computed in advance; instead, they may be graph may or may not be computed in advance; instead, they may be
decided upon the detection of a change from a clean slate. decided upon the detection of a change from a clean slate.
Furthermore, the PLR decision may be distributed, which yields a Furthermore, the PLR decision may be distributed, which yields a
large combination of possible and dependent decisions, with no node large combination of possible and dependent decisions, with no node
in the network capable of reporting which is the current DetNet Path in the network capable of reporting which is the current DetNet path
within the recovery graph. within the recovery graph.
In DetNet [DetNet-ARCHI] terms, a recovery graph has the following In DetNet [DetNet-ARCHI] terms, a recovery graph has the following
properties: properties:
* A recovery graph is a Layer 3 abstraction built upon IP links * A recovery graph is a Layer 3 abstraction built upon IP links
between routers. A router may form multiple IP links over a between routers. A router may form multiple IP links over a
single radio interface. single radio interface.
* A recovery graph has one Ingress and one Egress node, which * A recovery graph has one ingress and one egress node, which
operate as DetNet Edge nodes. operate as DetNet Edge nodes.
* The graph of a recovery graph is reversible, meaning that packets * A recovery graph is reversible, meaning that packets can be routed
can be routed against the flow of data packets, e.g., to carry OAM against the flow of data packets, e.g., to carry OAM measurements
measurements or control messages back to the Ingress. or control messages back to the ingress.
* The vertices of that graph are DetNet Relay Nodes that operate at * The vertices of a recovery graph are DetNet Relay nodes that
the DetNet Service sub-layer and provide the PREOF functions. operate at the DetNet Service sub-layer and provide the PREOF
functions.
* The topological edges of the graph are strict sequences of DetNet * The topological edges of a recovery graph are strict sequences of
Transit nodes that operate at the DetNet Forwarding sub-layer. DetNet Transit nodes that operate at the DetNet forwarding sub-
layer.
Figure 2 illustrates the generic concept of a recovery graph, between Figure 2 illustrates the generic concept of a recovery graph, between
an Ingress Node and an Egress Node. The recovery graph is composed an ingress node and an egress node. The recovery graph is composed
of forward protection paths, forward Segments, and crossing Segments of forward protection paths, forward segments, and crossing segments
(see the definitions of those terms in the next sections). The (see the definitions of those terms in the next sections). The
recovery graph contains at least two protection paths: a main path recovery graph contains at least two protection paths: a main path
and a backup path. and a backup path.
------------------- forward direction ----------------------> ------------------- forward direction ---------------------->
a ==> b ==> C -=- F ==> G ==> h T1 a ==> b ==> C -=- F ==> G ==> h T1
/ \ / | \ / / \ / | \ /
I o n E -=- T2 I o n E -=- T2
\ / \ | / \ \ / \ | / \
p ==> q ==> R -=- T ==> U ==> v T3 p ==> q ==> R -=- T ==> U ==> v T3
I: Ingress I: Ingress
E: Egress E: Egress
T1, T2, T3: external targets T1, T2, T3: external targets
Uppercase: DetNet Relay Nodes Uppercase: DetNet Relay nodes
Lowercase: DetNet Transit nodes Lowercase: DetNet Transit nodes
Figure 2: A Recovery Graph and Its Components Figure 2: A Recovery Graph and Its Components
Of note: Of note:
I ==> a ==> b ==> C: A forward Segment to targets F and o I ==> a ==> b ==> C: A forward segment to targets F and o
C ==> o ==> T: A forward Segment to target T (and/or U) C ==> o ==> T: A forward segment to target T (and/or U)
G | n | U: A crossing Segment to targets G or U G | n | U: A crossing segment to targets G or U
I -> F -> E: A forward protection path to targets T1, T2, and T3 I -> F -> E: A forward protection path to targets T1, T2, and T3
I, a, b, C, F, G, h, E: A path to T1, T2, and/or T3 I, a, b, C, F, G, h, E: A path to T1, T2, and/or T3
I, p, q, R, o, F, G, h, E: A segment-crossing protection path I, p, q, R, o, F, G, h, E: A segment-crossing protection path
3.3.3. Forward and Crossing 3.3.3. Forward and Crossing
Forward refers to progress towards the Egress of the recovery graph. Forward refers to progress towards the egress of the recovery graph.
Forward links are directional, and packets that are forwarded along Forward links are directional, and packets that are forwarded along
the recovery graph can only be transmitted along the link direction. the recovery graph can only be transmitted along the link direction.
Crossing links are bidirectional, meaning that they can be used in Crossing links are bidirectional, meaning that they can be used in
both directions, though a given packet may use the link in one both directions, though a given packet may use the link in one
direction only. A Segment can be forward, in which case it is direction only. A segment can be forward, in which case it is
composed of forward links only, or it can be crossing, in which case composed of forward links only, or it can be crossing, in which case
it is composed of crossing links only. A protection path is always it is composed of crossing links only. A protection path is always
forward, meaning that it is composed of forward links and Segments. forward, meaning that it is composed of forward links and segments.
3.3.4. Protection Path 3.3.4. Protection Path
A protection path is an end-to-end forward path between the Ingress A protection path is an end-to-end forward path between the ingress
and Egress Nodes of a recovery graph. A protection path in a and egress nodes of a recovery graph. A protection path in a
recovery graph is expressed as a strict sequence of DetNet Relay recovery graph is expressed as a strict sequence of DetNet Relay
Nodes or as a loose sequence of DetNet Relay Nodes that are joined by nodes or as a loose sequence of DetNet Relay nodes that are joined by
Segments in the recovery graph. Background information on the segments in the recovery graph. Background information on the
concepts related to protection paths can be found in [RFC4427] and concepts related to protection paths can be found in [RFC4427] and
[RFC6378]. [RFC6378].
3.3.5. Segment 3.3.5. Segment
A Segment is a strict sequence of DetNet Transit nodes between two A segment is a strict sequence of DetNet Transit nodes between two
DetNet Relay Nodes; a Segment of a recovery graph is composed DetNet Relay nodes; a segment of a recovery graph is composed
topologically of two vertices of the recovery graph and one edge of topologically of two vertices of the recovery graph and one edge of
the recovery graph between those vertices. the recovery graph between those vertices.
3.4. Deterministic Networking 3.4. Deterministic Networking
This document reuses the terminology in Section 2 of [RFC8557] and This document reuses the terminology in Section 2 of [RFC8557] and
Section 4.1.2 of [DetNet-ARCHI] for deterministic networking and Section 4.1.2 of [DetNet-ARCHI] for deterministic networking and
deterministic networks. This documents also uses the following deterministic networks. This document also uses the following terms.
terms.
3.4.1. The DetNet Planes 3.4.1. The DetNet Planes
[DetNet-ARCHI] defines three planes: the Application (User) Plane, [DetNet-ARCHI] defines three planes: the Application (User) Plane,
the Controller Plane, and the Network Plane. The DetNet Network the Controller Plane, and the Network Plane. The DetNet Network
Plane is composed of a Data Plane (packet forwarding) and an Plane is composed of a Data Plane (packet forwarding) and an
Operational Plane where OAM operations take place. In the Network Operational Plane where OAM operations take place. In the Network
Plane, the DetNet Service sub-layer focuses on flow protection (e.g., Plane, the DetNet Service sub-layer focuses on flow protection (e.g.,
using redundancy) and can be fully operated at Layer 3, while the using redundancy) and can be fully operated at Layer 3, while the
DetNet forwarding sub-layer establishes the paths, associates the DetNet forwarding sub-layer establishes the paths, associates the
flows to the paths, ensures the availability of the necessary flows to the paths, ensures the availability of the necessary
resources, and leverages Layer 2 functionalities for timely delivery resources, and leverages Layer 2 functionalities for timely delivery
to the next DetNet system. For more information, see Section 2. to the next DetNet system. For more information, see Section 2.
3.4.2. Flow 3.4.2. Flow
A flow is a collection of consecutive IP packets defined by the upper A flow is a collection of consecutive IP packets defined by the upper
layers and signaled by the same 5-tuple or 6-tuple (see Section 5.1 layers and signaled by the same 5-tuple or 6-tuple (see Section 5.1
of [RFC8939]). Packets of the same flow must be placed on the same of [RFC8939]). Packets of the same flow must be placed on the same
recovery graph to receive an equivalent treatment from Ingress to recovery graph to receive an equivalent treatment from ingress to
Egress within the recovery graph. Multiple flows may be transported egress within the recovery graph. Multiple flows may be transported
along the same recovery graph. The DetNet Path that is selected for along the same recovery graph. The DetNet path that is selected for
the flow may change over time under the control of the PLR. the flow may change over time under the control of the PLR.
3.4.3. Residence Time 3.4.3. Residence Time
A residence time (RT) is defined as the time interval between when A residence time (RT) is defined as the time interval between when
the reception of a packet starts and the transmission of the packet the reception of a packet starts and the transmission of the packet
begins. In the context of RAW, RT is useful for a transit nodes, not begins. In the context of RAW, RT is useful for a transit nodes, not
ingress or egress nodes. ingress or egress nodes.
3.4.4. L3 Deterministic Flow Identifier 3.4.4. L3 Deterministic Flow Identifier
The classic IP 5-tuple that identifies a flow comprises the source The classic IP 5-tuple that identifies a flow comprises the source
IP, destination IP, source port, destination port, and the Upper- IP, destination IP, source port, destination port, and the Upper-
Layer Protocol (ULP). DetNet uses a 6-tuple where the extra field is Layer Protocol (ULP). DetNet uses a 6-tuple where the extra field is
the Differentiated Services Code Point (DSCP) field in the packet the Differentiated Services Code Point (DSCP) field in the packet
(see Section 3.3 of [DetNet-DP]). The IPv6 flow label is not used (see Section 3.3 of [DetNet-DP]). The IPv6 flow label is not used
for that purpose. for that purpose.
3.4.5. Time-Sensitive Networking 3.4.5. Time-Sensitive Networking
Time-Sensitive Networking (TSN) denotes the efforts at IEEE 802 for Time-Sensitive Networking (TSN) denotes the IEEE efforts regarding
deterministic networking, originally for use on Ethernet. Wireless deterministic networking, originally for use on Ethernet. See [TSN].
TSN (WTSN) denotes extensions of the TSN work on wireless media such Wireless TSN (WTSN) denotes extensions of the TSN work on wireless
as the selected RAW technologies [RAW-TECHNOS]. media, such as the RAW technologies described in [RAW-TECHNOS].
3.4.6. Lower-Layer API 3.4.6. Lower-Layer API
RAW includes the concept of a lower-layer API (LL API) that provides RAW includes the concept of a lower-layer API (LL API) that provides
an interface between the lower-layer (e.g., wireless) technology and an interface between the lower-layer (e.g., wireless) technology and
the DetNet layers. The LL API is technology dependent as what the the DetNet layers. The LL API is technology dependent as what the
lower layers expose towards the DetNet layers may vary. Furthermore, lower layers expose towards the DetNet layers may vary. Furthermore,
different RAW technologies are equipped with different reliability different RAW technologies are equipped with different reliability
features (e.g., short-range broadcast, Multiple User - Multiple Input features (e.g., short-range broadcast, Multiple User - Multiple Input
Multiple Output (MU-MIMO), PHY rate and other Modulation Coding Multiple Output (MU-MIMO), physical layer (PHY) rate and other
Scheme (MCS) adaptation, coding and retransmissions methods, and Modulation Coding Scheme (MCS) adaptation, coding and retransmissions
constructive interference and overhearing; see [RAW-TECHNOS] for more methods, and constructive interference and overhearing; see
details). The LL API enables interactions between the reliability [RAW-TECHNOS] for more details). The LL API enables interactions
functions provided by the lower layer and the reliability functions between the reliability functions provided by the lower layer and the
provided by DetNet. That is, the LL API makes cross-layer reliability functions provided by DetNet. That is, the LL API makes
optimization possible for the reliability functions of different cross-layer optimization possible for the reliability functions of
layers depending on the actual exposure provided via the LL API by different layers depending on the actual exposure provided via the LL
the given RAW technology. The Dynamic Link Exchange Protocol (DLEP) API by the given RAW technology. The Dynamic Link Exchange Protocol
[DLEP] is an example of a protocol that can be used to implement the (DLEP) [DLEP] is an example of a protocol that can be used to
LL API. implement the LL API.
3.5. Reliability and Availability 3.5. Reliability and Availability
This document uses the following terms relating to reliability and This document uses the following terms relating to reliability and
availability in the context of the RAW work. availability in the context of the RAW work.
3.5.1. Service Level Agreement 3.5.1. Service Level Agreement
In the context of RAW, a Service Level Agreement (SLA) is a contract In the context of RAW, a Service Level Agreement (SLA) is a contract
between a provider (the network) and a client, the application flow, between a provider (the network) and a client (the application flow)
defining measurable metrics such as latency boundaries, consecutive that defines measurable metrics such as latency boundaries,
losses, and Packet Delivery Ratio (PDR). consecutive losses, and Packet Delivery Ratio (PDR).
3.5.2. Service Level Objective 3.5.2. Service Level Objective
A Service Level Objective (SLO) is one term in the SLA, for which A Service Level Objective (SLO) is one term in the SLA, for which
specific network setting and operations are implemented. For specific network setting and operations are implemented. For
instance, a dynamic tuning of packet redundancy addresses an SLO of instance, a dynamic tuning of packet redundancy addresses an SLO of
consecutive losses in a row by augmenting the chances of delivery of consecutive losses in a row by augmenting the chances of delivery of
a packet that follows a loss. a packet that follows a loss.
3.5.3. Service Level Indicator 3.5.3. Service Level Indicator
A Service Level Indicator (SLI) measures the compliance of an SLO to A Service Level Indicator (SLI) measures the compliance of an SLO to
the terms of the contract. For instance, it can be the statistics of the terms of the contract. For instance, it can be the statistics of
individual losses and losses in a row as time series. individual losses or losses in a row during a certain amount of time.
3.5.4. Precision Availability Metrics 3.5.4. Precision Availability Metrics
Precision Availability Metrics (PAMs) [RFC9544] aim to capture Precision Availability Metrics (PAMs) [RFC9544] aim to capture
service levels for a flow, specifically the degree to which the flow service levels for a flow, specifically the degree to which the flow
complies with the SLOs that are in effect. complies with the SLOs that are in effect.
3.5.5. Reliability 3.5.5. Reliability
Reliability is a measure of the probability that an item (e.g., Reliability is a measure of the probability that an item (e.g.,
system or network) will perform its intended function with no failure system or network) will perform its intended function with no failure
for a stated period of time (or for a stated number of demands or for a stated period of time (or for a stated number of demands or
load) under stated environmental conditions. In other words, load) under stated environmental conditions. In other words,
reliability is the probability that an item will be in an uptime reliability is the probability that an item will be in an uptime
state (i.e., fully operational or ready to perform) for a stated state (i.e., fully operational or ready to perform) for a stated
mission (e.g., to provide an SLA). See more in [NASA1]. mission (e.g., to provide an SLA). See more in [NASA1].
3.5.6. Availability 3.5.6. Availability
Availability is the probability of an item's (e.g., a network's) Availability is the probability of an item's (e.g., a network's)
mission readiness (e.g., to provide an SLA), an uptime state with the mission readiness (e.g., to provide an SLA). Availability is
likelihood of a recoverable downtime state. Availability is
expressed as (uptime)/(uptime+downtime). Note that it is expressed as (uptime)/(uptime+downtime). Note that it is
availability that addresses downtime (including time for maintenance, availability that addresses downtime (including time for maintenance,
repair, and replacement activities) and not reliability. See more in repair, and replacement activities) and not reliability. See more in
[NASA2]. [NASA2].
4. Reliable and Available Wireless 4. Reliable and Available Wireless
4.1. High Availability Engineering Principles 4.1. High Availability Engineering Principles
The reliability criteria of a critical system pervade its elements, The reliability criteria of a critical system pervade its elements,
skipping to change at line 953 skipping to change at line 961
networks, this is rarely the case. Packet loss cannot be fully networks, this is rarely the case. Packet loss cannot be fully
avoided, and the systems are built to resist some loss. This can be avoided, and the systems are built to resist some loss. This can be
done by using redundancy with retries (as in HARQ), Packet done by using redundancy with retries (as in HARQ), Packet
Replication and Elimination (PRE) FEC, and Network Coding (e.g., Replication and Elimination (PRE) FEC, and Network Coding (e.g.,
using FEC with Static Context Header Compression (SCHC) [RFC8724] using FEC with Static Context Header Compression (SCHC) [RFC8724]
fragments). Also, in a typical control loop, linear interpolation fragments). Also, in a typical control loop, linear interpolation
from the previous measurements can be used. from the previous measurements can be used.
However, the linear interpolation method cannot resist multiple However, the linear interpolation method cannot resist multiple
consecutive losses, and a high MTBF is desired as a guarantee that consecutive losses, and a high MTBF is desired as a guarantee that
this does not happen, in other words, that the number of losses in a the number of losses in a row is bounded. In this case, what is
row can be bounded. In this case, what is really desired is a really desired is a Maximum Consecutive Loss (MCL). If the number of
Maximum Consecutive Loss (MCL). (See also Section 5.9.5 of [DLEP].) losses in a row passes the MCL, the control loop has to abort, and
If the number of losses in a row passes the MCL, the control loop has the system (e.g., the production line) may need to enter an emergency
to abort, and the system (e.g., the production line) may need to stop condition.
enter an emergency stop condition.
Engineers that build automated processes may use the network Engineers that build automated processes may use the network
reliability expressed in nines as an MTBF as a proxy to indicate an reliability expressed in nines as the MTBF and as a proxy to indicate
MCL, e.g., as described in Section 7.4 of "Deterministic Networking an MCL, e.g., as described in Section 7.4 of "Deterministic
Use Cases" [RFC8578]. Networking Use Cases" [RFC8578].
4.3. Wireless Effects Affecting Reliability 4.3. Wireless Effects Affecting Reliability
In contrast with wired networks, errors in transmission are the In contrast with wired networks, errors in transmission are the
predominant source of packet loss in wireless networks. predominant source of packet loss in wireless networks.
The root cause for the loss may be of multiple origins, calling for The root cause for the loss may be of multiple origins, calling for
the use of different forms of diversity: the use of different forms of diversity:
Multipath fading: A destructive interference by a reflection of the Multipath fading: A destructive interference by a reflection of the
skipping to change at line 1022 skipping to change at line 1029
removed, or as long as the interferer (e.g., a radar in the ISM band) removed, or as long as the interferer (e.g., a radar in the ISM band)
keeps transmitting, a continuous stream of packets are affected. keeps transmitting, a continuous stream of packets are affected.
The key technique to combat those unpredictable losses is diversity. The key technique to combat those unpredictable losses is diversity.
Different forms of diversity are necessary to combat different causes Different forms of diversity are necessary to combat different causes
of loss, and the use of diversity must be maximized to optimize the of loss, and the use of diversity must be maximized to optimize the
PDR. PDR.
A single packet may be sent at different times (time diversity) over A single packet may be sent at different times (time diversity) over
diverse paths (spatial diversity) that rely on diverse radio channels diverse paths (spatial diversity) that rely on diverse radio channels
(frequency diversity) and diverse PHY technologies (e.g., narrowband (frequency diversity) leveraging diverse PHY technologies (e.g.,
versus spread spectrum), or diverse codes. Using time diversity narrowband versus spread spectrum or diverse codes). Using time
defeats short-term interferences; spatial diversity combats very diversity defeats short-term interferences; spatial diversity combats
local causes of interference such as multipath fading; narrowband and very local causes of interference such as multipath fading;
spread spectrum are relatively innocuous to one another and can be narrowband and spread spectrum are relatively innocuous to one
used for diversity in the presence of the other. another and can be used for diversity in the presence of the other.
5. The RAW Conceptual Model 5. The RAW Conceptual Model
RAW extends the conceptual model described in Section 4 of RAW extends the conceptual model described in Section 4 of
"Deterministic Networking Architecture" [DetNet-ARCHI] with the PLR "Deterministic Networking Architecture" [DetNet-ARCHI] with the PLR
at the Service sub-layer, as illustrated in Figure 3. The PLR (see at the Service sub-layer, as illustrated in Figure 3. The PLR (see
Section 6.5) is a point of local reaction to provide additional Section 6.5) provides additional agility against transmission loss.
agility against transmission loss. For example, the PLR can act For example, the PLR can act based on indications from the lower
based on indications from the lower layer or based on OAM. layer or based on OAM.
| packets going | ^ packets coming ^ | packets going | ^ packets coming ^
v down the stack v | up the stack | v down the stack v | up the stack |
+-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
| Source | | Destination | | Source | | Destination |
+-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
| Service sub-layer: | | Service sub-layer: | | Service sub-layer: | | Service sub-layer: |
| Packet sequencing | | Duplicate elimination | | Packet sequencing | | Duplicate elimination |
| Flow replication | | Flow merging | | Flow replication | | Flow merging |
| Packet encoding | | Packet decoding | | Packet encoding | | Packet decoding |
skipping to change at line 1062 skipping to change at line 1069
+-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
| Lower layers | | Lower layers | | Lower layers | | Lower layers |
+-----------------------+ +-----------------------+ +-----------------------+ +-----------------------+
v ^ v ^
\_________________________/ \_________________________/
Figure 3: Extended DetNet Data Plane Protocol Stack Figure 3: Extended DetNet Data Plane Protocol Stack
5.1. The RAW Planes 5.1. The RAW Planes
The RAW Nodes are DetNet Relay Nodes that operate in the RAW Network The RAW nodes are DetNet Relay nodes that operate in the RAW Network
Plane and are capable of additional diversity mechanisms and Plane and are capable of additional diversity mechanisms and
measurement functions related to the radio interface. RAW leverages measurement functions related to the radio interface. RAW leverages
an Operational Plane orientation function (that typically operates an Operational Plane orientation function (that typically operates
inside the Ingress Edge Nodes) to dynamically adapt the path of the inside the ingress Edge nodes) to dynamically adapt the path of the
packets and optimize the resource usage. packets and optimize the resource usage.
In the case of centralized routing operations, the RAW Controller In the case of centralized routing operations, the RAW Controller
Plane Function (CPF) interacts with RAW Nodes over a Southbound API. Plane Function (CPF) interacts with RAW nodes over a Southbound API.
It consumes data and information from the network and generates It consumes data and information from the network and generates
knowledge and wisdom to help steer the traffic optimally inside a knowledge and wisdom to help steer the traffic optimally inside a
recovery graph. recovery graph.
DetNet Routing DetNet Routing
CPF CPF CPF CPF CPF CPF CPF CPF
Southbound API Southbound API
_-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._- _-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-._-
skipping to change at line 1095 skipping to change at line 1102
Ingress __/ / \ / \ \____Egress Ingress __/ / \ / \ \____Egress
End __ / \ / .- -- . \ ___ End End __ / \ / .- -- . \ ___ End
Node \ / \ / .-( ). \ / Node Node \ / \ / .-( ). \ / Node
\_ RAW ___ RAW ___(Non-RAW Nodes)__ RAW _/ \_ RAW ___ RAW ___(Non-RAW Nodes)__ RAW _/
Node Node (___.______.____) Node Node Node (___.______.____) Node
Figure 4: RAW Nodes (Centralized Routing Case) Figure 4: RAW Nodes (Centralized Routing Case)
When a new flow is defined, the routing function uses its current When a new flow is defined, the routing function uses its current
knowledge of the network to build a new recovery graph between an knowledge of the network to build a new recovery graph between an
Ingress End System and an Egress End System for that flow; it ingress End System and an egress End System for that flow; it
indicates to the RAW Nodes where the PREOF and/or radio diversity and indicates to the RAW nodes where the PREOF and/or radio diversity and
reliability operations may be actioned in the Network Plane. reliability operations may be actioned in the Network Plane.
* The recovery graph may be strict, meaning that the DetNet * The recovery graph may be strict, meaning that the DetNet
forwarding sub-layer operations are enforced end to end. forwarding sub-layer operations are enforced end to end.
* The recovery graph may be expressed loosely to enable traversing a * The recovery graph may be expressed loosely to enable traversing a
non-RAW subnetwork as in Figure 7. In that case, RAW cannot non-RAW subnetwork as in Figure 7. In that case, RAW cannot
leverage end-to-end DetNet and cannot provide latency guarantees. leverage end-to-end DetNet and cannot provide latency guarantees.
The information that the orientation function reports to the routing The information that the orientation function reports to the routing
function includes may be a time-aggregated, e.g., statistical function may be time aggregated (e.g., statistical), to match the
fashion, to match the longer-term operation of the routing function. longer-term operation of the routing function. Example information
Example information includes link-layer metrics such as link includes link-layer metrics such as link bandwidth (the medium speed
bandwidth (the medium speed depends dynamically on the mode of the depends dynamically on the mode of the PHY layer), number of flows
PHY layer), number of flows (bandwidth that can be reserved for a (bandwidth that can be reserved for a flow depends on the number and
flow depends on the number and size of flows sharing the spectrum), size of flows sharing the spectrum), and the average and mean squared
and the average and mean squared deviation of availability and deviation of availability and reliability metrics (such as PDR) over
reliability metrics (such as PDR) over long periods of time. It may long periods of time. It may also report an aggregated Expected
also report an aggregated Expected Transmission Count (ETX) or a Transmission Count (ETX) or a variation of it.
variation of it.
Based on those metrics, the routing function installs the recovery Based on those metrics, the routing function installs the recovery
graph with enough redundant forwarding solutions to ensure that the graph with enough redundant forwarding solutions to ensure that the
Network Plane can reliably deliver the packets within an SLA Network Plane can reliably deliver the packets within an SLA
associated with the flows that it transports. The SLA defines end- associated with the flows that it transports. The SLA defines end-
to-end reliability and availability requirements, in which to-end reliability and availability requirements, in which
reliability may be expressed as a successful delivery in order and reliability may be expressed as a successful delivery in order and
within a bounded delay of at least one copy of a packet. within a bounded delay of at least one copy of a packet.
Depending on the use case and the SLA, the recovery graph may Depending on the use case and the SLA, the recovery graph may
comprise non-RAW segments, either interleaved inside the recovery comprise non-RAW segments, either interleaved inside the recovery
graph (e.g., over tunnels) or all the way to the Egress End Node graph (e.g., over tunnels) or all the way to the egress End node
(e.g., a server in the local wired domain). RAW observes the lower- (e.g., a server in the local wired domain). RAW observes the lower-
layer links between RAW nodes (typically radio links) and the end-to- layer links between RAW nodes (typically radio links) and the end-to-
end network-layer operation to decide at all times which of the end network-layer operation to decide at all times which of the
diversity schemes is actioned by which RAW Nodes. diversity schemes is actioned by which RAW nodes.
Once a recovery graph is established, per-segment and end-to-end Once a recovery graph is established, per-segment and end-to-end
reliability and availability statistics are periodically reported to reliability and availability statistics are periodically reported to
the routing function to ensure that the SLA can be met; if not, then the routing function to ensure that the SLA can be met; if not, then
the recovery graph is recomputed. the recovery graph is recomputed.
5.2. RAW Versus Upper and Lower Layers 5.2. RAW Versus Upper and Lower Layers
RAW builds on DetNet-provided features such as scheduling and RAW builds on DetNet-provided features such as scheduling and
shaping. In particular, RAW inherits the DetNet guarantees on end- shaping. In particular, RAW inherits the DetNet guarantees on end-
skipping to change at line 1154 skipping to change at line 1160
reliability mechanisms have no side effect on upper layers, e.g., on reliability mechanisms have no side effect on upper layers, e.g., on
transport-layer packet recovery. RAW operations include possible transport-layer packet recovery. RAW operations include possible
rerouting, which in turn may affect the ordering of a burst of rerouting, which in turn may affect the ordering of a burst of
packets. RAW also inherits PREOF from DetNet, which can be used to packets. RAW also inherits PREOF from DetNet, which can be used to
reorder packets before delivery to the upper layers. As a result, reorder packets before delivery to the upper layers. As a result,
DetNet in general and RAW in particular offer a smoother transport DetNet in general and RAW in particular offer a smoother transport
experience for the upper layers than the Internet at large, with experience for the upper layers than the Internet at large, with
ultra-low jitter and loss. ultra-low jitter and loss.
RAW improves the reliability of transmissions and the availability of RAW improves the reliability of transmissions and the availability of
communication resources, and should be seen as a dynamic optimization the communication resources and should be seen as a dynamic
of the use of redundancy to maintain it within certain boundaries. optimization of the use of redundancy to maintain reliability and
For instance, ARQ (which provides one-hop reliability through availability metrics within certain boundaries. For instance, ARQ
acknowledgements and retries) and FEC codes (such as turbo codes (which provides one-hop reliability through acknowledgements and
which reduce the PER) are typically operated at Layer 2 and Layer 1, retries) and FEC codes (such as turbo codes which reduce the PER) are
respectively. In both cases, redundant transmissions improve the typically operated at Layer 2 and Layer 1, respectively. In both
one-hop reliability at the expense of energy and latency, which are cases, redundant transmissions improve the one-hop reliability at the
the resources that RAW must control. In order to achieve its goals, expense of energy and latency, which are the resources that RAW must
RAW may leverage the lower-layer operations by abstracting the control. In order to achieve its goals, RAW may leverage the lower-
concept and providing hints to the lower layers on the desired layer operations by abstracting the concept and providing hints to
outcome (e.g., in terms of reliability and timeliness), as opposed to the lower layers on the desired outcome (e.g., in terms of
performing the actual operations at Layer 3. reliability and timeliness), as opposed to performing the actual
operations at Layer 3.
Guarantees such as bounded latency depend on the upper layers Guarantees such as bounded latency depend on the upper layers
(transport or application) to provide the payload in volumes and at (transport or application) to provide the payload in volumes and at
times that match the contract with the DetNet sub-layers and the times that match the contract with the DetNet sub-layers and the
layers below. An excess of incoming traffic at the DetNet Ingress layers below. An excess of incoming traffic at the DetNet ingress
may result in dropping or queueing of packets and can entail loss, may result in dropping or queueing of packets and can entail loss,
latency, or jitter; this violates the guarantees that are provided latency, or jitter; this violates the guarantees that are provided
inside the DetNet Network. inside the DetNet Network.
When the traffic from upper layers matches the expectation of the When the traffic from upper layers matches the expectation of the
lower layers, RAW still depends on DetNet mechanisms and the lower lower layers, RAW still depends on DetNet mechanisms and the lower
layers to provide the timing and physical resource guarantees that layers to provide the timing and physical resource guarantees that
are needed to match the traffic SLA. When the availability of the are needed to match the traffic SLA. When the availability of the
physical resource varies, RAW acts on the distribution of the traffic physical resource varies, RAW acts on the distribution of the traffic
to leverage alternates within a finite set of potential resources. to leverage alternates within a finite set of potential resources.
skipping to change at line 1196 skipping to change at line 1203
specialized APIs (e.g., L2 triggers) via monitoring and measurement specialized APIs (e.g., L2 triggers) via monitoring and measurement
protocols such as Bidirectional Forwarding Detection (BFD) [RFC5880] protocols such as Bidirectional Forwarding Detection (BFD) [RFC5880]
and Simple Two-way Active Measurement Protocol (STAMP) [RFC8762], and Simple Two-way Active Measurement Protocol (STAMP) [RFC8762],
respectively, or via a control protocol exchange with the lower layer respectively, or via a control protocol exchange with the lower layer
(e.g., DLEP [DLEP]). It may then be processed and exported through (e.g., DLEP [DLEP]). It may then be processed and exported through
OAM messaging or via a YANG data model and exposed to the Controller OAM messaging or via a YANG data model and exposed to the Controller
Plane. Plane.
5.3. RAW and DetNet 5.3. RAW and DetNet
RAW leverages the DetNet Forwarding sub-layer and requires the RAW leverages the DetNet forwarding sub-layer and requires the
support of OAM in DetNet Transit Nodes (see Figure 3 of support of OAM in DetNet Transit nodes (see Figure 3 of
[DetNet-ARCHI]) for the dynamic acquisition of link capacity and [DetNet-ARCHI]) for the dynamic acquisition of link capacity and
state to maintain a strict RAW service end to end over a DetNet state to maintain a strict RAW service end to end over a DetNet
Network. In turn, DetNet and thus RAW may benefit from or leverage Network. In turn, DetNet and thus RAW may benefit from or leverage
functionality such as that provided by TSN at the lower layers. functionality such as that provided by TSN at the lower layers.
RAW extends DetNet to improve the protection against link errors such RAW extends DetNet to improve the protection against link errors such
as transient flapping that are far more common in wireless links. as transient flapping that are far more common in wireless links.
Nevertheless, for the most part, the RAW methods are applicable to Nevertheless, for the most part, the RAW methods are applicable to
wired links as well, e.g., when energy savings are desirable and the wired links as well, e.g., when energy savings are desirable and the
available path diversity exceeds 1+1 linear redundancy. available path diversity exceeds 1+1 linear redundancy.
RAW adds sub-layer functions that operate in the DetNet Operational RAW adds sub-layer functions that operate in the DetNet Operational
Plane, which is part of the Network Plane. The RAW orientation Plane, which is part of the Network Plane. The RAW orientation
function may run only in the DetNet Edge Nodes (Ingress Edge Node or function may run only in the DetNet Edge nodes (ingress Edge node or
End System), or it can also run in DetNet Relay Nodes when the RAW End System), or it can also run in DetNet Relay nodes when the RAW
operations are distributed along the recovery graph. The RAW Service operations are distributed along the recovery graph. The RAW Service
sub-layer includes the PLR, which decides the DetNet Path for the sub-layer includes the PLR, which decides the DetNet path for the
future packets of a flow along the DetNet Path, Maintenance End future packets of a flow along the DetNet path, Maintenance End
Points (MEPs) on edge nodes, and Maintenance Intermediate Points Points (MEPs) on edge nodes, and Maintenance Intermediate Points
(MIPs) within. The MEPs trigger, and learn from, OAM observations (MIPs) within. The MEPs trigger, and learn from, OAM observations
and feed the PLR for its next decision. and feed the PLR for its next decision.
As illustrated in Figure 5, RAW extends the DetNet Stack (see As illustrated in Figure 5, RAW extends the DetNet Stack (see
Figure 4 of [DetNet-ARCHI] and Figure 3) with additional Figure 4 of [DetNet-ARCHI] and Figure 3) with additional
functionality at the DetNet Service sub-layer for the actuation of functionality at the DetNet Service sub-layer for the actuation of
PREOF based on the PLR decision. DetNet operates at Layer 3, PREOF based on the PLR decision. DetNet operates at Layer 3,
leveraging abstractions of the lower layers and APIs that control leveraging abstractions of the lower layers and APIs that control
those abstractions. For instance, DetNet already leverages lower those abstractions. For instance, DetNet already leverages lower
skipping to change at line 1239 skipping to change at line 1246
effect, the LL API provides an abstraction to the DetNet layer that effect, the LL API provides an abstraction to the DetNet layer that
can be used to push reliability and timing hints, like suggesting X can be used to push reliability and timing hints, like suggesting X
retries (min, max) within a time window or sending unicast (one next retries (min, max) within a time window or sending unicast (one next
hop) or multicast (for overhearing). In the other direction up the hop) or multicast (for overhearing). In the other direction up the
stack, the RAW PLR needs hints about the radio conditions such as L2 stack, the RAW PLR needs hints about the radio conditions such as L2
triggers (e.g., RSSI, LQI, or ETX) over all the wireless hops. triggers (e.g., RSSI, LQI, or ETX) over all the wireless hops.
RAW uses various OAM functionalities at the different layers. For RAW uses various OAM functionalities at the different layers. For
instance, the OAM function in the DetNet Service sub-layer may instance, the OAM function in the DetNet Service sub-layer may
perform Active and/or Hybrid OAM to estimate the link and path perform Active and/or Hybrid OAM to estimate the link and path
availability, either end to end or limited to a Segment. The RAW availability, either end to end or limited to a segment. The RAW
functions may be present in the Service sub-layer in DetNet Edge and functions may be present in the Service sub-layer in DetNet Edge and
Relay Nodes. Relay nodes.
+-----------------+ +-------------------+ +-----------------+ +-------------------+
| Routing | | OAM Control | | Routing | | OAM Control |
+-----------------+ +-------------------+ +-----------------+ +-------------------+
Controller Plane Controller Plane
+-+-+-+-+-+-+-+-+ Southbound Interface -+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+ Southbound Interface -+-+-+-+-+-+-+-+-+-+-+-+
Network Plane Network Plane
| |
skipping to change at line 1270 skipping to change at line 1277
| Repair (PLR) | | End Point (MEP) | . | Repair (PLR) | | End Point (MEP) | .
+-----------------+ +-------------------+ | +-----------------+ +-------------------+ |
. .
| |
Figure 5: RAW Function Placement (Centralized Routing Case) Figure 5: RAW Function Placement (Centralized Routing Case)
There are two main proposed models to deploy RAW and DetNet: strict There are two main proposed models to deploy RAW and DetNet: strict
(Figure 6) and loose (Figure 7). In the strict model, illustrated in (Figure 6) and loose (Figure 7). In the strict model, illustrated in
Figure 6, RAW operates over a continuous DetNet service end to end Figure 6, RAW operates over a continuous DetNet service end to end
between the Ingress and the Egress Edge Nodes or End Systems. between the ingress and the egress Edge nodes or End Systems.
In the loose model, illustrated in Figure 7, RAW may traverse a In the loose model, illustrated in Figure 7, RAW may traverse a
section of the network that is not serviced by DetNet. RAW / OAM may section of the network that is not serviced by DetNet. RAW OAM may
observe the end-to-end traffic and make the best of the available observe the end-to-end traffic and make the best of the available
resources, but it may not expect the DetNet guarantees over all resources, but it may not expect the DetNet guarantees over all
paths. For instance, the packets between two wireless entities may paths. For instance, the packets between two wireless entities may
be relayed over a wired infrastructure, in which case RAW observes be relayed over a wired infrastructure, in which case RAW observes
and controls the transmission over the wireless first and last hops, and controls the transmission over the wireless first and last hops,
as well as end-to-end metrics such as latency, jitter, and delivery as well as end-to-end metrics such as latency, jitter, and delivery
ratio. This operation is loose since the structure and properties of ratio. This operation is loose since the structure and properties of
the wired infrastructure are ignored and may be either controlled by the wired infrastructure are ignored and may be either controlled by
other means such as DetNet/TSN or neglected in the face of the other means such as DetNet/TSN or neglected in the face of the
wireless hops. wireless hops.
A minimal Forwarding sub-layer service is provided at all DetNet A minimal forwarding sub-layer service is provided at all DetNet
Nodes to ensure that the OAM information flows. DetNet Relay Nodes nodes to ensure that the OAM information flows. DetNet Relay nodes
may or may not support RAW services, whereas the DetNet Edge Nodes may or may not support RAW services, whereas the DetNet Edge nodes
are required to support RAW in any case. DetNet guarantees, such as are required to support RAW in any case. DetNet guarantees, such as
bounded latency, are provided end to end. RAW extends the DetNet bounded latency, are provided end to end. RAW extends the DetNet
Service sub-layer to optimize the use of resources. Service sub-layer to optimize the use of resources.
--------------------Flow Direction----------------------------------> --------------------Flow Direction---------------------------------->
+---------+ +---------+
| RAW | | RAW |
| Control | | Control |
+---------+ +---------+ +---------+ +---------+ +---------+ +---------+
skipping to change at line 1315 skipping to change at line 1322
Ingress Transit Relay Egress Ingress Transit Relay Egress
Edge ... Nodes ... Nodes ... Edge Edge ... Nodes ... Nodes ... Edge
Node Node Node Node
<------------------End-to-End DetNet Service-----------------------> <------------------End-to-End DetNet Service----------------------->
Figure 6: RAW over DetNet (Strict Model) Figure 6: RAW over DetNet (Strict Model)
In the loose model (illustrated in Figure 7), RAW operates over a In the loose model (illustrated in Figure 7), RAW operates over a
partial DetNet service where typically only the Ingress and the partial DetNet service where typically only the ingress and the
Egress End Systems support RAW. The DetNet domain may extend beyond egress End Systems support RAW. The DetNet domain may extend beyond
the Ingress Node, or there may be a DetNet domain starting at an the ingress node, or there may be a DetNet domain starting at an
Ingress Edge Node at the first hop after the End System. ingress Edge node at the first hop after the End System.
In the loose model, RAW cannot observe the hops in the network, and In the loose model, RAW cannot observe the hops in the network, and
the path beyond the first hop is opaque; RAW can still observe the the path beyond the first hop is opaque; RAW can still observe the
end-to-end behavior and use Layer 3 measurements to decide whether to end-to-end behavior and use Layer 3 measurements to decide whether to
replicate a packet and select the first-hop interface(s). replicate a packet and select the first-hop interface(s).
--------------------Flow Direction----------------------------------> --------------------Flow Direction---------------------------------->
+---------+ +---------+
| RAW | | RAW |
skipping to change at line 1349 skipping to change at line 1356
Ingress Transit Relay Tunnel Egress Ingress Transit Relay Tunnel Egress
End ... Nodes ... Nodes ... ... End End ... Nodes ... Nodes ... ... End
System System System System
<---------------Partitioned DetNet Service-------------------------> <---------------Partitioned DetNet Service------------------------->
Figure 7: RAW over DetNet (Loose Model) Figure 7: RAW over DetNet (Loose Model)
6. The RAW Control Loop 6. The RAW Control Loop
The RAW architecture is based on an abstract OODA Loop that controls The RAW architecture is based on an abstract OODA loop that controls
the operation of a recovery graph. The generic concept involves the the operation of a recovery graph. The generic concept involves the
following: following:
1. Operational Plane measurement protocols for OAM to observe (like 1. Operational Plane measurement protocols allow OAM to observe
the first "O" in "OODA") some or all hops along a recovery graph (like the first "O" in "OODA") some or all hops along a recovery
as well as the end-to-end packet delivery. graph as well as the end-to-end packet delivery.
2. The DetNet Controller Plane establishes primary and protection 2. The DetNet Controller Plane establishes primary and protection
paths for use by the RAW Network Plane. The orientation function paths for use by the RAW Network Plane. The orientation function
reports data and information such as link statistics to be used reports data and information such as link statistics to be used
by the routing function to compute, install, and maintain the by the routing function to compute, install, and maintain the
recovery graphs. The routing function may also generate recovery graphs. The routing function may also generate
intelligence such as a trained model for link quality prediction, intelligence such as a trained model for link quality prediction,
which in turn can be used by the orientation function (like the which in turn can be used by the orientation function (like the
second "O" in "OODA") to influence the Path selection by the PLR second "O" in "OODA") to influence the path selection by the PLR
within the RAW OODA loop. within the RAW OODA loop.
3. A PLR operates at the DetNet Service sub-layer and hosts the 3. A PLR operates at the DetNet Service sub-layer and hosts the
decision function (like the "D" in "OODA"). The decision decision function (like the "D" in "OODA"). The decision
function determines which DetNet Paths will be used for future function determines which DetNet paths will be used for future
packets that are routed within the recovery graph. packets that are routed within the recovery graph.
4. Service protection actions that are actuated or triggered over 4. Service protection actions are actuated or triggered over the LL
the LL API by the PLR to increase the reliability of the end-to- API by the PLR to increase the reliability of the end-to- end
end transmissions. The RAW architecture also covers in-situ transmissions. The RAW architecture also covers in-situ
signaling that is embedded within live user traffic [RFC9378] signaling that is embedded within live user traffic [RFC9378]
(e.g., via OAM) when the decision is acted (like the "A" in (e.g., via OAM) when the decision is acted (like the "A" in
"OODA") upon by a node that is downstream in the recovery graph "OODA") upon by a node that is downstream in the recovery graph
from the PLR. from the PLR.
The overall OODA Loop optimizes the use of redundancy to achieve the The overall OODA loop optimizes the use of redundancy to achieve the
required reliability and availability SLO(s) while minimizing the use required reliability and availability SLO(s) while minimizing the use
of constrained resources such as spectrum and battery. of constrained resources such as spectrum and battery.
6.1. Routing Timescale Versus Forwarding Timescale 6.1. Routing Timescale Versus Forwarding Timescale
With DetNet, the Controller Plane Function (CPF) handles the routing With DetNet, the Controller Plane Function (CPF) handles the routing
computation and maintenance. With RAW, the routing operation is computation and maintenance. With RAW, the routing operation is
segregated from the RAW Control Loop, so it may reside in the segregated from the RAW control loop, so it may reside in the
Controller Plane, whereas the control loop itself happens in the Controller Plane, whereas the control loop itself happens in the
Network Plane. To achieve RAW capabilities, the routing operation is Network Plane. To achieve RAW capabilities, the routing operation is
extended to generate the information required by the orientation extended to generate the information required by the orientation
function in the loop. For example, the routing function may propose function in the loop. For example, the routing function may propose
DetNet Paths to be used as a reflex action in response to network DetNet paths to be used as a reflex action in response to network
events or provide an aggregated history that the orientation function events or provide an aggregated history that the orientation function
can use to make a decision. can use to make a decision.
In a wireless mesh, the path to a routing function located in the In a wireless mesh, the path to a routing function located in the
controller plane can be expensive and slow, possibly going across the Controller Plane can be expensive and slow, possibly going across the
whole mesh and back. Reaching the Controller Plane can also be slow whole mesh and back. Reaching the Controller Plane can also be slow
in regard to the speed of events that affect the forwarding operation in regard to the speed of events that affect the forwarding operation
in the Network Plane at the radio layer. Note that a distributed in the Network Plane at the radio layer. Note that a distributed
routing protocol may also take time and consume excessive wireless routing protocol may also take time and consume excessive wireless
resources to reconverge to a new optimized state. resources to reconverge to a new optimized state.
As a result, the DetNet routing function is not expected to be aware As a result, the DetNet routing function is not expected to be aware
of and react to very transient changes. The abstraction of a link at of and react to very transient changes. The abstraction of a link at
the routing level is expected to use statistical metrics that the routing level is expected to use statistical metrics that
aggregate the behavior of a link over long periods of time and aggregate the behavior of a link over long periods of time and
represent its properties as shades of gray as opposed to numerical represent its properties as shades of gray as opposed to numerical
values such as a link quality indicator or a Boolean value for either values such as a link quality indicator or a Boolean value for either
up or down. up or down.
The interaction between the network nodes and the routing function is The interaction between the network nodes and the routing function is
handled by the orientation function, which builds reports to the handled by the orientation function, which reports to the routing
routing function and sends control information in a digested form function and sends control information in a digested form back to the
back to the RAW node to be used inside a forwarding control loop for RAW node to be used inside a forwarding control loop for traffic
traffic steering. steering.
Figure 8 illustrates a Network Plane recovery graph with links P-Q Figure 8 illustrates a Network Plane recovery graph with links P-Q
and N-E flapping, possibly in a transient fashion due to short-term and N-E flapping, possibly in a transient fashion due to short-term
interferences and possibly for a longer time (e.g., due to obstacles interferences and possibly for a longer time (e.g., due to obstacles
between the sender and the receiver or hardware failures). In order between the sender and the receiver or hardware failures). In order
to maintain a received redundancy around a value of 2 (for instance), to maintain a received redundancy around a value of 2 (for instance),
RAW may leverage a higher ARQ on these hops if the overall latency RAW may leverage a higher ARQ on these hops if the overall latency
permits the extra delay or enable alternate paths between ingress I permits the extra delay or enable alternate paths between ingress I
and egress E. For instance, RAW may enable protection path I ==> F and egress E. For instance, RAW may enable protection path I ==> F
==> N ==> Q ==> M ==> R ==> E that routes around both issues and ==> N ==> Q ==> M ==> R ==> E that routes around both issues and
skipping to change at line 1510 skipping to change at line 1517
observe the local state of the links and some or all hops along a observe the local state of the links and some or all hops along a
recovery graph as well as the end-to-end packet delivery (see more recovery graph as well as the end-to-end packet delivery (see more
in Section 6.3). Information can also be provided by lower-layer in Section 6.3). Information can also be provided by lower-layer
interfaces such as DLEP. interfaces such as DLEP.
Orient: The orientation function reports data and information such Orient: The orientation function reports data and information such
as the link statistics and leverages offline-computed wisdom and as the link statistics and leverages offline-computed wisdom and
knowledge to orient the PLR for its forwarding decision (see more knowledge to orient the PLR for its forwarding decision (see more
in Section 6.4). in Section 6.4).
Decide: A local PLR decides which DetNet Path to use for future Decide: A local PLR decides which DetNet path to use for future
packet(s) that are routed along the recovery graph (see more in packet(s) that are routed along the recovery graph (see more in
Section 6.5). Section 6.5).
Act: PREOF Data Plane actions are controlled by the PLR over the LL Act: PREOF Data Plane actions are controlled by the PLR over the LL
API to increase the reliability of the end-to-end transmission. API to increase the reliability of the end-to-end transmission.
The RAW architecture also covers in-situ signaling when the The RAW architecture also covers in-situ signaling when the
decision is acted by a node that is down the recovery graph from decision is acted by a node that is down the recovery graph from
the PLR (see more in Section 6.6). the PLR (see more in Section 6.6).
+-------> Orientation ---------+ +-------> Orientation ---------+
skipping to change at line 1536 skipping to change at line 1543
| Service sub-layer | | Service sub-layer |
| v | v
Observe (OAM) Decide (PLR) Observe (OAM) Decide (PLR)
^ | ^ |
| | | |
| | | |
+------- Act (LL API) <--------+ +------- Act (LL API) <--------+
Figure 9: The RAW OODA Loop Figure 9: The RAW OODA Loop
The overall OODA Loop optimizes the use of redundancy to achieve the The overall OODA loop optimizes the use of redundancy to achieve the
required reliability and availability Service Level Agreement (SLA) required reliability and availability Service Level Agreement (SLA)
while minimizing the use of constrained resources such as spectrum while minimizing the use of constrained resources such as spectrum
and battery. and battery.
6.3. Observe: RAW OAM 6.3. Observe: RAW OAM
The RAW in-situ OAM operation in the Network Plane may observe either The RAW in-situ OAM operation in the Network Plane may observe either
a full recovery graph or the DetNet Path that is being used at this a full recovery graph or the DetNet path that is being used at this
time. As packets may be load balanced, replicated, eliminated, and/ time. As packets may be load balanced, replicated, eliminated, and/
or fragmented for Network Coding FEC, the RAW in-situ operation needs or fragmented for Network Coding FEC, the RAW in-situ operation needs
to be able to signal which operation occurred to an individual to be able to signal which operation occurred to an individual
packet. packet.
Active RAW OAM may be needed to observe the unused segments and Active RAW OAM may be needed to observe the unused segments and
evaluate the desirability of a rerouting decision. evaluate the desirability of a rerouting decision.
Finally, the RAW Service sub-layer Assurance may observe the Finally, the RAW Service sub-layer Service Assurance may observe the
individual PREOF operation of a DetNet Relay Node to ensure that it individual PREOF operation of a DetNet Relay node to ensure that it
is conforming; this might require injecting an OAM packet at an is conforming; this might require injecting an OAM packet at an
upstream point inside the recovery graph and extracting that packet upstream point inside the recovery graph and extracting that packet
at another point downstream before it reaches the egress. at another point downstream before it reaches the egress.
This observation feeds the RAW PLR that makes the decision on which This observation feeds the RAW PLR that makes the decision on which
path is used at which RAW Node, for one packet or a small continuous path is used at which RAW node, for one packet or a small continuous
series of packets. series of packets.
In the case of end-to-end protection in a wireless mesh, the recovery In the case of end-to-end protection in a wireless mesh, the recovery
graph is strict and congruent with the path so all links are graph is strict and congruent with the path so all links are
observed. observed.
Conversely, in the case of Radio Access Protection, illustrated in Conversely, in the case of Radio Access Protection, illustrated in
Figure 10, the recovery graph is loose and only the first hop is Figure 10, the recovery graph is loose and only the first hop is
observed; the rest of the path is abstracted and considered observed; the rest of the path is abstracted and considered
infinitely reliable. The loss of a packet is attributed to the infinitely reliable. The loss of a packet is attributed to the
skipping to change at line 1600 skipping to change at line 1607
<----------------------L3-----------------------> <----------------------L3----------------------->
Figure 10: Observed Links in Radio Access Protection Figure 10: Observed Links in Radio Access Protection
The links that are not observed by OAM are opaque to it, meaning that The links that are not observed by OAM are opaque to it, meaning that
the OAM information is carried across and possibly echoed as data, the OAM information is carried across and possibly echoed as data,
but there is no information captured in intermediate nodes. In the but there is no information captured in intermediate nodes. In the
example above, the tunnel underlay is opaque and not controlled by example above, the tunnel underlay is opaque and not controlled by
RAW; still, RAW OAM measures the end-to-end latency and delivery RAW; still, RAW OAM measures the end-to-end latency and delivery
ratio for packets sent via RAN 1, RAN 2, and RAN 3, and determines ratio for packets sent via RAN 1, RAN 2, and RAN 3, and determines
whether a packet should be sent over either or a collection of those whether a packet should be sent over either access link or a
access links. collection of those access links.
6.4. Orient: The RAW-Extended DetNet Operational Plane 6.4. Orient: The RAW-Extended DetNet Operational Plane
RAW separates the long timescale at which a recovery graph is RAW separates the long timescale at which a recovery graph is
computed and installed from the short timescale at which the computed and installed from the short timescale at which the
forwarding decision is taken for one or a few packets (see forwarding decision is taken for one or a few packets (see
Section 6.1) that experience the same path until the network Section 6.1) that experience the same path until the network
conditions evolve and another path is selected within the same conditions evolve and another path is selected within the same
recovery graph. recovery graph.
The recovery graph computation is out of scope, but RAW expects that The recovery graph computation is out of scope, but RAW expects that
the CPF that installs the recovery graph also provides related the CPF that installs the recovery graph also provides related
knowledge in the form of metadata about the links, segments, and knowledge in the form of metadata about the links, segments, and
possible DetNet Paths. That metadata can be a pre-digested possible DetNet paths. That metadata can be a pre-digested
statistical model and may include prediction of future flaps and statistical model and may include prediction of future flaps and
packet loss, as well as recommended actions when that happens. packet loss, as well as recommended actions when that happens.
The metadata may include: The metadata may include:
* A set of pre-determined DetNet Paths that are prepared to match * A set of pre-determined DetNet paths that are prepared to match
expected link-degradation profiles, so the DetNet Relay Nodes can expected link-degradation profiles, so the DetNet Relay nodes can
take reflex rerouting actions when facing a degradation that take reflex rerouting actions when facing a degradation that
matches one such profile; and matches one such profile; and
* Link-quality statistics history and pre-trained models (e.g., to * Link-quality statistics history and pre-trained models (e.g., to
predict the short-term variation of quality of the links in a predict the short-term variation of quality of the links in a
recovery graph). recovery graph).
The recovery graph is installed with measurable objectives that are The recovery graph is installed with measurable objectives that are
computed by the CPF to achieve the RAW SLA. The objectives can be computed by the CPF to achieve the RAW SLA. The objectives can be
expressed as any of the maximum number of packets lost in a row, expressed as any of the maximum number of packets lost in a row,
bounded latency, maximal jitter, maximum number of interleaved out- bounded latency, maximal jitter, maximum number of interleaved out-
of-order packets, average number of copies received at the of-order packets, average number of copies received at the
elimination point, and maximal delay between the first and the last elimination point, and maximal delay between the first and the last
received copy of the same packet. received copy of the same packet.
6.5. Decide: The Point of Local Repair 6.5. Decide: The Point of Local Repair
The RAW OODA Loop operates at the path selection timescale to provide The RAW OODA loop operates at the path selection timescale to provide
agility versus the brute-force approach of flooding the whole agility versus the brute-force approach of flooding the whole
recovery graph. The OODA Loop controls, within the redundant recovery graph. Within the redundant solutions that are proposed by
solutions that are proposed by the routing function, which is used the routing function, the OODA loop controls what is used for each
for each packet to provide a reliable and available service while packet and provides a reliable and available service while minimizing
minimizing the waste of constrained resources. the waste of constrained resources.
To that effect, RAW defines the Point of Local Repair (PLR), which To that effect, RAW defines the Point of Local Repair (PLR), which
performs rapid local adjustments of the forwarding tables within the performs rapid local adjustments of the forwarding tables within the
path diversity that is available in that in the recovery graph. The path diversity that is available in that in the recovery graph. The
PLR enables exploitation of the richer forwarding capabilities at a PLR enables exploitation of the richer forwarding capabilities at a
faster timescale over a portion of the recovery graph, in either a faster timescale over a portion of the recovery graph, in either a
loose or a strict fashion. loose or a strict fashion.
The PLR operates on metrics that evolve quickly and need to be The PLR operates on metrics that evolve quickly and need to be
advertised at a fast rate (but only locally, within the recovery advertised at a fast rate (but only locally, within the recovery
graph), and the PLR reacts on the metric updates by changing the graph), and the PLR reacts to the metric updates by changing the
DetNet path in use for the affected flows. DetNet path in use for the affected flows.
The rapid changes in the forwarding decisions are made and contained The rapid changes in the forwarding decisions are made and contained
within the scope of a recovery graph, and the actions of the PLR are within the scope of a recovery graph, and the actions of the PLR are
not signaled outside the recovery graph. This is as opposed to the not signaled outside the recovery graph. This is as opposed to the
routing function that must observe the whole network and optimize all routing function that must observe the whole network and optimize all
the recovery graphs globally, which can only be done at a slow pace the recovery graphs globally, which can only be done at a slow pace
and with long-term statistical metrics, as presented in Table 1. and with long-term statistical metrics, as presented in Table 1.
+===============+=========================+=====================+ +===============+=========================+=====================+
skipping to change at line 1686 skipping to change at line 1693
| | graphs to optimize | of protection paths | | | graphs to optimize | of protection paths |
| | globally | | | | globally | |
+===============+-------------------------+---------------------+ +===============+-------------------------+---------------------+
| Considered | Averaged, statistical, | Instantaneous | | Considered | Averaged, statistical, | Instantaneous |
| Metrics | shade of grey | values / boolean | | Metrics | shade of grey | values / boolean |
| | | condition | | | | condition |
+===============+-------------------------+---------------------+ +===============+-------------------------+---------------------+
Table 1: Centralized Decision Versus PLR Table 1: Centralized Decision Versus PLR
The PLR sits in the DetNet Forwarding sub-layer of Edge and Relay The PLR sits in the DetNet forwarding sub-layer of Edge and Relay
Nodes. The PLR operates on the packet flow, learning the recovery nodes. The PLR operates on the packet flow, learning the recovery
graph and path-selection information from the packet and possibly graph and path-selection information from the packet and possibly
making a local decision and retagging the packet to indicate so. On making a local decision and retagging the packet to indicate so. On
the other hand, the PLR interacts with the lower layers (through the other hand, the PLR interacts with the lower layers (through
triggers and DLEP) and with its peers (through OAM) to obtain up-to- triggers and DLEP) and with its peers (through OAM) to obtain up-to-
date information about its links and the quality of the overall date information about its links and the quality of the overall
recovery graph, respectively, as illustrated in Figure 11. recovery graph, respectively, as illustrated in Figure 11.
| |
Packet | going Packet | going
down the | stack down the | stack
skipping to change at line 1719 skipping to change at line 1726
| Lower layers | | Lower layers |
+..........v.....................^...................^.v........+ +..........v.....................^...................^.v........+
Frame | sent Frame | L2 ack Active | | OAM Frame | sent Frame | L2 ack Active | | OAM
over | wireless in | in and | | out over | wireless in | in and | | out
v | | v v | | v
Figure 11: PLR Conceptual Interfaces Figure 11: PLR Conceptual Interfaces
6.6. Act: DetNet Path Selection and Reliability Functions 6.6. Act: DetNet Path Selection and Reliability Functions
The main action by the PLR is the swapping of the DetNet Path within The main action by the PLR is the swapping of the DetNet path within
the recovery graph for the future packets. The candidate DetNet the recovery graph for the future packets. The candidate DetNet
Paths represent different energy and spectrum profiles and provide paths represent different energy and spectrum profiles and provide
protection against different failures. protection against different failures.
The LL API enriches the DetNet protection services (PREOF) with the The LL API enriches the DetNet protection services (PREOF) with the
possibility to interact with lower-layer, one-hop reliability possibility to interact with lower-layer, one-hop reliability
functions that are more typical to wireless than wired, including functions that are more typical with wireless links than with wired
ARQ, FEC, and other techniques such as overhearing and constructive ones, including ARQ, FEC, and other techniques such as overhearing
interferences. Because RAW may be leveraged on wired links (e.g., to and constructive interferences. Because RAW may be leveraged on
save power), it is not expected that all lower layers support all wired links (e.g., to save power), it is not expected that all lower
those capabilities. layers support all those capabilities.
RAW provides hints to the lower-layer services on the desired RAW provides hints to the lower-layer services on the desired
outcome, and the lower layer acts on those hints to provide the best outcome, and the lower layer acts on those hints to provide the best
approximation of that outcome, e.g., a level of reliability for one- approximation of that outcome, e.g., a level of reliability for one-
hop transmission within a bounded budget of time and/or energy. hop transmission within a bounded budget of time and/or energy.
Thus, the LL API makes possible cross-layer optimization for Thus, the LL API makes possible cross-layer optimization for
reliability depending on the actual abstraction provided. That is, reliability depending on the actual abstraction provided. That is,
some reliability functions are controlled from Layer 3 using an some reliability functions are controlled from Layer 3 using an
abstract interface, while they are really operated at the lower abstract interface, while they are really operated at the lower
layers. layers.
The RAW Path Selection can be implemented in both centralized and The RAW path selection can be implemented in both centralized and
distributed approaches. In the centralized approach, the PLR may distributed approaches. In the centralized approach, the PLR may
obtain a set of pre-computed DetNet paths matching a set of expected obtain a set of pre-computed DetNet paths matching a set of expected
failures and apply the appropriate DetNet paths for the current state failures and apply the appropriate DetNet paths for the current state
of the wireless links. In the distributed approach, the signaling in of the wireless links. In the distributed approach, the signaling in
the packet may be more abstract than an explicit Path, and the PLR the packet may be more abstract than an explicit path, and the PLR
decision might be revised along the selected DetNet Path based on a decision might be revised along the selected DetNet path based on a
better knowledge of the rest of the way. better knowledge of the rest of the way.
The dynamic DetNet Path selection in RAW avoids the waste of critical The dynamic DetNet path selection in RAW avoids the waste of critical
resources such as spectrum and energy while providing for the assured resources such as spectrum and energy while providing for the assured
SLA, e.g., by rerouting and/or adding redundancy only when a loss SLA, e.g., by rerouting and/or adding redundancy only when a loss
spike is observed. spike is observed.
7. Security Considerations 7. Security Considerations
7.1. Collocated Denial-of-Service Attacks 7.1. Collocated Denial-of-Service Attacks
RAW leverages diversity (e.g., spatial and time diversity, coding RAW leverages diversity (e.g., spatial and time diversity, coding
diversity, and frequency diversity), possibly using heterogeneous diversity, and frequency diversity), possibly using heterogeneous
skipping to change at line 1788 skipping to change at line 1795
7.2. Layer 2 Encryption 7.2. Layer 2 Encryption
Radio networks typically encrypt at the Media Access Control (MAC) Radio networks typically encrypt at the Media Access Control (MAC)
layer to protect the transmission. If the encryption is per pair of layer to protect the transmission. If the encryption is per pair of
peers, then certain RAW operations like promiscuous overhearing peers, then certain RAW operations like promiscuous overhearing
become impractical. become impractical.
7.3. Forced Access 7.3. Forced Access
A RAW policy may typically select the cheapest collection of links A RAW policy typically selects the cheapest collection of links that
that matches the requested SLA, e.g., use free Wi-Fi versus paid 3GPP matches the requested SLA, e.g., use free Wi-Fi versus paid 3GPP
access. By defeating the cheap connectivity (e.g., PHY-layer access. By defeating the cheap connectivity (e.g., PHY-layer
interference) the attacker can force an End System to use the paid interference) the attacker can force an End System to use the paid
access and increase the cost of the transmission for the user. access and increase the cost of the transmission for the user.
Similar attacks may also be used to deplete resources in lower-power Similar attacks may also be used to deplete resources in lower-power
nodes by forcing additional transmissions for FEC and ARQ, and attack nodes by forcing additional transmissions for FEC and ARQ, and attack
metrics such as battery life of the nodes. By affecting the metrics such as battery life of the nodes. By affecting the
transmissions and the associated routing metrics in one area, an transmissions and the associated routing metrics in one area, an
attacker may force the traffic and cause congestion along a remote attacker may force the traffic and cause congestion along a remote
path, thus reducing the overall throughput of the network. path, thus reducing the overall throughput of the network.
8. IANA Considerations 8. IANA Considerations
This document has no IANA actions. This document has no IANA actions.
9. References 9. References
9.1. Normative References 9.1. Normative References
[DetNet-ARCHI]
Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", RFC 8655,
DOI 10.17487/RFC8655, October 2019,
<https://www.rfc-editor.org/info/rfc8655>.
[DetNet-OAM]
Mirsky, G., Theoleyre, F., Papadopoulos, G., Bernardos,
CJ., Varga, B., and J. Farkas, "Framework of Operations,
Administration, and Maintenance (OAM) for Deterministic
Networking (DetNet)", RFC 9551, DOI 10.17487/RFC9551,
March 2024, <https://www.rfc-editor.org/info/rfc9551>.
[RAW-TECHNOS] [RAW-TECHNOS]
Thubert, P., Ed., Cavalcanti, D., Vilajosana, X., Schmitt, Thubert, P., Ed., Cavalcanti, D., Vilajosana, X., Schmitt,
C., and J. Farkas, "Reliable and Available Wireless (RAW) C., and J. Farkas, "Reliable and Available Wireless (RAW)
Technologies", RFC 9913, DOI 10.17487/RFC9913, February Technologies", RFC 9913, DOI 10.17487/RFC9913, February
2026, <https://www.rfc-editor.org/info/rfc9913>. 2026, <https://www.rfc-editor.org/info/rfc9913>.
[TSN] IEEE, "Time-Sensitive Networking (TSN)",
<https://1.ieee802.org/tsn/>.
[RFC4427] Mannie, E., Ed. and D. Papadimitriou, Ed., "Recovery [RFC4427] Mannie, E., Ed. and D. Papadimitriou, Ed., "Recovery
(Protection and Restoration) Terminology for Generalized (Protection and Restoration) Terminology for Generalized
Multi-Protocol Label Switching (GMPLS)", RFC 4427, Multi-Protocol Label Switching (GMPLS)", RFC 4427,
DOI 10.17487/RFC4427, March 2006, DOI 10.17487/RFC4427, March 2006,
<https://www.rfc-editor.org/info/rfc4427>. <https://www.rfc-editor.org/info/rfc4427>.
[RFC6291] Andersson, L., van Helvoort, H., Bonica, R., Romascanu, [RFC6291] Andersson, L., van Helvoort, H., Bonica, R., Romascanu,
D., and S. Mansfield, "Guidelines for the Use of the "OAM" D., and S. Mansfield, "Guidelines for the Use of the "OAM"
Acronym in the IETF", BCP 161, RFC 6291, Acronym in the IETF", BCP 161, RFC 6291,
DOI 10.17487/RFC6291, June 2011, DOI 10.17487/RFC6291, June 2011,
<https://www.rfc-editor.org/info/rfc6291>. <https://www.rfc-editor.org/info/rfc6291>.
[RFC7799] Morton, A., "Active and Passive Metrics and Methods (with [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with
Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
May 2016, <https://www.rfc-editor.org/info/rfc7799>. May 2016, <https://www.rfc-editor.org/info/rfc7799>.
[RFC8557] Finn, N. and P. Thubert, "Deterministic Networking Problem [RFC8557] Finn, N. and P. Thubert, "Deterministic Networking Problem
Statement", RFC 8557, DOI 10.17487/RFC8557, May 2019, Statement", RFC 8557, DOI 10.17487/RFC8557, May 2019,
<https://www.rfc-editor.org/info/rfc8557>. <https://www.rfc-editor.org/info/rfc8557>.
[DetNet-ARCHI] [TSN] IEEE, "Time-Sensitive Networking (TSN)",
Finn, N., Thubert, P., Varga, B., and J. Farkas, <https://1.ieee802.org/tsn/>.
"Deterministic Networking Architecture", RFC 8655,
DOI 10.17487/RFC8655, October 2019,
<https://www.rfc-editor.org/info/rfc8655>.
[DetNet-OAM]
Mirsky, G., Theoleyre, F., Papadopoulos, G., Bernardos,
CJ., Varga, B., and J. Farkas, "Framework of Operations,
Administration, and Maintenance (OAM) for Deterministic
Networking (DetNet)", RFC 9551, DOI 10.17487/RFC9551,
March 2024, <https://www.rfc-editor.org/info/rfc9551>.
9.2. Informative References 9.2. Informative References
[6TiSCH-ARCHI] [6TiSCH-ARCHI]
Thubert, P., Ed., "An Architecture for IPv6 over the Time- Thubert, P., Ed., "An Architecture for IPv6 over the Time-
Slotted Channel Hopping Mode of IEEE 802.15.4 (6TiSCH)", Slotted Channel Hopping Mode of IEEE 802.15.4 (6TiSCH)",
RFC 9030, DOI 10.17487/RFC9030, May 2021, RFC 9030, DOI 10.17487/RFC9030, May 2021,
<https://www.rfc-editor.org/info/rfc9030>. <https://www.rfc-editor.org/info/rfc9030>.
[RFC9049] Dawkins, S., Ed., "Path Aware Networking: Obstacles to [DetNet-DP]
Deployment (A Bestiary of Roads Not Taken)", RFC 9049, Varga, B., Ed., Farkas, J., Berger, L., Malis, A., and S.
DOI 10.17487/RFC9049, June 2021, Bryant, "Deterministic Networking (DetNet) Data Plane
<https://www.rfc-editor.org/info/rfc9049>. Framework", RFC 8938, DOI 10.17487/RFC8938, November 2020,
<https://www.rfc-editor.org/info/rfc8938>.
[DetNet-PLANE]
Malis, A. G., Geng, X., Ed., Chen, M., Varga, B., and C.
J. Bernardos, "A Framework for Deterministic Networking
(DetNet) Controller Plane", Work in Progress, Internet-
Draft, draft-ietf-detnet-controller-plane-framework-14, 9
September 2025, <https://datatracker.ietf.org/doc/html/
draft-ietf-detnet-controller-plane-framework-14>.
[DLEP] Ratliff, S., Jury, S., Satterwhite, D., Taylor, R., and B.
Berry, "Dynamic Link Exchange Protocol (DLEP)", RFC 8175,
DOI 10.17487/RFC8175, June 2017,
<https://www.rfc-editor.org/info/rfc8175>.
[FRR] Shand, M. and S. Bryant, "IP Fast Reroute Framework",
RFC 5714, DOI 10.17487/RFC5714, January 2010,
<https://www.rfc-editor.org/info/rfc5714>.
[INT-ARCHI] [INT-ARCHI]
Braden, R., Ed., "Requirements for Internet Hosts - Braden, R., Ed., "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122, Communication Layers", STD 3, RFC 1122,
DOI 10.17487/RFC1122, October 1989, DOI 10.17487/RFC1122, October 1989,
<https://www.rfc-editor.org/info/rfc1122>. <https://www.rfc-editor.org/info/rfc1122>.
[RFC8939] Varga, B., Ed., Farkas, J., Berger, L., Fedyk, D., and S. [NASA1] Adams, T., "RELIABILITY: Definition & Quantitative
Bryant, "Deterministic Networking (DetNet) Data Plane: Illustration", <https://extapps.ksc.nasa.gov/Reliability/
IP", RFC 8939, DOI 10.17487/RFC8939, November 2020, Documents/150814-3bWhatIsReliability.pdf>.
<https://www.rfc-editor.org/info/rfc8939>.
[RFC8578] Grossman, E., Ed., "Deterministic Networking Use Cases", [NASA2] Adams, T., "Availability",
RFC 8578, DOI 10.17487/RFC8578, May 2019, <https://extapps.ksc.nasa.gov/Reliability/
<https://www.rfc-editor.org/info/rfc8578>. Documents/160727.1_Availability_What_is_it.pdf>.
[RAW-USE-CASES] [RAW-USE-CASES]
Bernardos, CJ., Ed., Papadopoulos, G., Thubert, P., and F. Bernardos, CJ., Ed., Papadopoulos, G., Thubert, P., and F.
Theoleyre, "Reliable and Available Wireless (RAW) Use Theoleyre, "Reliable and Available Wireless (RAW) Use
Cases", RFC 9450, DOI 10.17487/RFC9450, August 2023, Cases", RFC 9450, DOI 10.17487/RFC9450, August 2023,
<https://www.rfc-editor.org/info/rfc9450>. <https://www.rfc-editor.org/info/rfc9450>.
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981, DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>. <https://www.rfc-editor.org/info/rfc791>.
[RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S. [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, DOI 10.17487/RFC2205, Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
September 1997, <https://www.rfc-editor.org/info/rfc2205>. September 1997, <https://www.rfc-editor.org/info/rfc2205>.
[TE] Farrel, A., Ed., "Overview and Principles of Internet
Traffic Engineering", RFC 9522, DOI 10.17487/RFC9522,
January 2024, <https://www.rfc-editor.org/info/rfc9522>.
[RFC9544] Mirsky, G., Halpern, J., Min, X., Clemm, A., Strassner,
J., and J. François, "Precision Availability Metrics
(PAMs) for Services Governed by Service Level Objectives
(SLOs)", RFC 9544, DOI 10.17487/RFC9544, March 2024,
<https://www.rfc-editor.org/info/rfc9544>.
[RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
Computation Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.
[RFC3366] Fairhurst, G. and L. Wood, "Advice to link designers on [RFC3366] Fairhurst, G. and L. Wood, "Advice to link designers on
link Automatic Repeat reQuest (ARQ)", BCP 62, RFC 3366, link Automatic Repeat reQuest (ARQ)", BCP 62, RFC 3366,
DOI 10.17487/RFC3366, August 2002, DOI 10.17487/RFC3366, August 2002,
<https://www.rfc-editor.org/info/rfc3366>. <https://www.rfc-editor.org/info/rfc3366>.
[RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast [RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090, Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
DOI 10.17487/RFC4090, May 2005, DOI 10.17487/RFC4090, May 2005,
<https://www.rfc-editor.org/info/rfc4090>. <https://www.rfc-editor.org/info/rfc4090>.
[RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
Computation Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<https://www.rfc-editor.org/info/rfc5880>. <https://www.rfc-editor.org/info/rfc5880>.
[FRR] Shand, M. and S. Bryant, "IP Fast Reroute Framework",
RFC 5714, DOI 10.17487/RFC5714, January 2010,
<https://www.rfc-editor.org/info/rfc5714>.
[RFC6378] Weingarten, Y., Ed., Bryant, S., Osborne, E., Sprecher, [RFC6378] Weingarten, Y., Ed., Bryant, S., Osborne, E., Sprecher,
N., and A. Fulignoli, Ed., "MPLS Transport Profile (MPLS- N., and A. Fulignoli, Ed., "MPLS Transport Profile (MPLS-
TP) Linear Protection", RFC 6378, DOI 10.17487/RFC6378, TP) Linear Protection", RFC 6378, DOI 10.17487/RFC6378,
October 2011, <https://www.rfc-editor.org/info/rfc6378>. October 2011, <https://www.rfc-editor.org/info/rfc6378>.
[RFC6551] Vasseur, JP., Ed., Kim, M., Ed., Pister, K., Dejean, N., [RFC6551] Vasseur, JP., Ed., Kim, M., Ed., Pister, K., Dejean, N.,
and D. Barthel, "Routing Metrics Used for Path Calculation and D. Barthel, "Routing Metrics Used for Path Calculation
in Low-Power and Lossy Networks", RFC 6551, in Low-Power and Lossy Networks", RFC 6551,
DOI 10.17487/RFC6551, March 2012, DOI 10.17487/RFC6551, March 2012,
<https://www.rfc-editor.org/info/rfc6551>. <https://www.rfc-editor.org/info/rfc6551>.
[RLFA-FRR] Bryant, S., Filsfils, C., Previdi, S., Shand, M., and N. [RFC8578] Grossman, E., Ed., "Deterministic Networking Use Cases",
So, "Remote Loop-Free Alternate (LFA) Fast Reroute (FRR)", RFC 8578, DOI 10.17487/RFC8578, May 2019,
RFC 7490, DOI 10.17487/RFC7490, April 2015, <https://www.rfc-editor.org/info/rfc8578>.
<https://www.rfc-editor.org/info/rfc7490>.
[RFC8724] Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and JC. [RFC8724] Minaburo, A., Toutain, L., Gomez, C., Barthel, D., and JC.
Zuniga, "SCHC: Generic Framework for Static Context Header Zuniga, "SCHC: Generic Framework for Static Context Header
Compression and Fragmentation", RFC 8724, Compression and Fragmentation", RFC 8724,
DOI 10.17487/RFC8724, April 2020, DOI 10.17487/RFC8724, April 2020,
<https://www.rfc-editor.org/info/rfc8724>. <https://www.rfc-editor.org/info/rfc8724>.
[DetNet-DP] [RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
Varga, B., Ed., Farkas, J., Berger, L., Malis, A., and S. Two-Way Active Measurement Protocol", RFC 8762,
Bryant, "Deterministic Networking (DetNet) Data Plane DOI 10.17487/RFC8762, March 2020,
Framework", RFC 8938, DOI 10.17487/RFC8938, November 2020, <https://www.rfc-editor.org/info/rfc8762>.
<https://www.rfc-editor.org/info/rfc8938>.
[DLEP] Ratliff, S., Jury, S., Satterwhite, D., Taylor, R., and B. [RFC8939] Varga, B., Ed., Farkas, J., Berger, L., Fedyk, D., and S.
Berry, "Dynamic Link Exchange Protocol (DLEP)", RFC 8175, Bryant, "Deterministic Networking (DetNet) Data Plane:
DOI 10.17487/RFC8175, June 2017, IP", RFC 8939, DOI 10.17487/RFC8939, November 2020,
<https://www.rfc-editor.org/info/rfc8175>. <https://www.rfc-editor.org/info/rfc8939>.
[RFC9049] Dawkins, S., Ed., "Path Aware Networking: Obstacles to
Deployment (A Bestiary of Roads Not Taken)", RFC 9049,
DOI 10.17487/RFC9049, June 2021,
<https://www.rfc-editor.org/info/rfc9049>.
[RFC9378] Brockners, F., Ed., Bhandari, S., Ed., Bernier, D., and T. [RFC9378] Brockners, F., Ed., Bhandari, S., Ed., Bernier, D., and T.
Mizrahi, Ed., "In Situ Operations, Administration, and Mizrahi, Ed., "In Situ Operations, Administration, and
Maintenance (IOAM) Deployment", RFC 9378, Maintenance (IOAM) Deployment", RFC 9378,
DOI 10.17487/RFC9378, April 2023, DOI 10.17487/RFC9378, April 2023,
<https://www.rfc-editor.org/info/rfc9378>. <https://www.rfc-editor.org/info/rfc9378>.
[RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
Two-Way Active Measurement Protocol", RFC 8762,
DOI 10.17487/RFC8762, March 2020,
<https://www.rfc-editor.org/info/rfc8762>.
[RFC9473] Enghardt, R. and C. Krähenbühl, "A Vocabulary of Path [RFC9473] Enghardt, R. and C. Krähenbühl, "A Vocabulary of Path
Properties", RFC 9473, DOI 10.17487/RFC9473, September Properties", RFC 9473, DOI 10.17487/RFC9473, September
2023, <https://www.rfc-editor.org/info/rfc9473>. 2023, <https://www.rfc-editor.org/info/rfc9473>.
[RFC9544] Mirsky, G., Halpern, J., Min, X., Clemm, A., Strassner,
J., and J. François, "Precision Availability Metrics
(PAMs) for Services Governed by Service Level Objectives
(SLOs)", RFC 9544, DOI 10.17487/RFC9544, March 2024,
<https://www.rfc-editor.org/info/rfc9544>.
[RFC9633] Geng, X., Ryoo, Y., Fedyk, D., Rahman, R., and Z. Li, [RFC9633] Geng, X., Ryoo, Y., Fedyk, D., Rahman, R., and Z. Li,
"Deterministic Networking (DetNet) YANG Data Model", "Deterministic Networking (DetNet) YANG Data Model",
RFC 9633, DOI 10.17487/RFC9633, October 2024, RFC 9633, DOI 10.17487/RFC9633, October 2024,
<https://www.rfc-editor.org/info/rfc9633>. <https://www.rfc-editor.org/info/rfc9633>.
[DetNet-PLANE] [RLFA-FRR] Bryant, S., Filsfils, C., Previdi, S., Shand, M., and N.
Malis, A. G., Geng, X., Ed., Chen, M., Varga, B., and C. So, "Remote Loop-Free Alternate (LFA) Fast Reroute (FRR)",
J. Bernardos, "A Framework for Deterministic Networking RFC 7490, DOI 10.17487/RFC7490, April 2015,
(DetNet) Controller Plane", Work in Progress, Internet- <https://www.rfc-editor.org/info/rfc7490>.
Draft, draft-ietf-detnet-controller-plane-framework-14, 9
September 2025, <https://datatracker.ietf.org/doc/html/
draft-ietf-detnet-controller-plane-framework-14>.
[NASA1] Adams, T., "RELIABILITY: Definition & Quantitative
Illustration", <https://extapps.ksc.nasa.gov/Reliability/
Documents/150814-3bWhatIsReliability.pdf>.
[NASA2] Adams, T., "Availability", [TE] Farrel, A., Ed., "Overview and Principles of Internet
<https://extapps.ksc.nasa.gov/Reliability/ Traffic Engineering", RFC 9522, DOI 10.17487/RFC9522,
Documents/160727.1_Availability_What_is_it.pdf>. January 2024, <https://www.rfc-editor.org/info/rfc9522>.
Acknowledgments Acknowledgments
This architecture could never have been completed without the support This architecture could never have been completed without the support
and recommendations from the DetNet chairs Janos Farkas and Lou and recommendations from the DetNet chairs Janos Farkas and Lou
Berger, and from Dave Black, the DetNet Tech Advisor. Many thanks to Berger, and from Dave Black, the DetNet Tech Advisor. Many thanks to
all of you. all of you.
The authors wish to thank Ketan Talaulikar, as well as Balazs Varga, The authors wish to thank Ketan Talaulikar, as well as Balazs Varga,
Dave Cavalcanti, Don Fedyk, Nicolas Montavont, and Fabrice Theoleyre Dave Cavalcanti, Don Fedyk, Nicolas Montavont, and Fabrice Theoleyre
skipping to change at line 2047 skipping to change at line 2054
Retired Retired
Email: buddenbergr@gmail.com Email: buddenbergr@gmail.com
Greg Mirsky Greg Mirsky
Ericsson Ericsson
Email: gregimirsky@gmail.com Email: gregimirsky@gmail.com
Author's Address Author's Address
Pascal Thubert (editor) Pascal Thubert (editor)
Independent
06330 Roquefort-les-Pins 06330 Roquefort-les-Pins
France France
Email: pascal.thubert@gmail.com Email: pascal.thubert@gmail.com
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