draft-ietf-detnet-problem-statement-09.txt   rfc8557.txt 
DetNet N. Finn Internet Engineering Task Force (IETF) N. Finn
Internet-Draft Huawei Technologies Co. Ltd Request for Comments: 8557 Huawei Technologies Co. Ltd
Intended status: Informational P. Thubert Category: Informational P. Thubert
Expires: June 21, 2019 Cisco ISSN: 2070-1721 Cisco
December 18, 2018 May 2019
Deterministic Networking Problem Statement Deterministic Networking Problem Statement
draft-ietf-detnet-problem-statement-09
Abstract Abstract
This paper documents the needs in various industries to establish This paper documents the needs in various industries to establish
multi-hop paths for characterized flows with deterministic multi-hop paths for characterized flows with deterministic
properties. properties.
Status of This Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction ....................................................2
2. On Deterministic Networking . . . . . . . . . . . . . . . . . 3 2. On Deterministic Networking .....................................4
3. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 6 3. Problem Statement ...............................................6
3.1. Supported topologies . . . . . . . . . . . . . . . . . . 6 3.1. Supported Topologies .......................................6
3.2. Flow Characterization . . . . . . . . . . . . . . . . . . 6 3.2. Flow Characterization ......................................6
3.3. Centralized Path Computation and Installation . . . . . . 6 3.3. Centralized Path Computation and Installation ..............7
3.4. Distributed Path Setup . . . . . . . . . . . . . . . . . 7 3.4. Distributed Path Setup .....................................8
3.5. Duplicated data format . . . . . . . . . . . . . . . . . 8 3.5. Duplicated Data Format .....................................8
4. Security Considerations . . . . . . . . . . . . . . . . . . . 8 4. Security Considerations .........................................9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 5. IANA Considerations .............................................9
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 6. Informative References .........................................10
7. Informative References . . . . . . . . . . . . . . . . . . . 9 Acknowledgments ...................................................11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 Authors' Addresses ................................................11
1. Introduction 1. Introduction
The Deterministic Networking Use Cases [I-D.ietf-detnet-use-cases] "Deterministic Networking Use Cases" [RFC8578] illustrates that
document illustrates that beyond the classical case of industrial beyond the classical case of Industrial Automation and Control
automation and control systems (IACS), there are in fact multiple Systems (IACSs) there are in fact multiple industries with strong,
industries with strong and yet relatively similar needs for and relatively similar, needs for deterministic network services with
deterministic network services with latency guarantees and ultra-low latency guarantees and ultra-low packet loss.
packet loss.
The generalization of the needs for more deterministic networks have The generalization of the needs for more deterministic networks has
led to the IEEE 802.1 AVB Task Group becoming the Time-Sensitive led to the IEEE 802.1 Audio Video Bridging (AVB) Task Group becoming
Networking (TSN) [IEEE802.1TSNTG] Task Group (TG), with a much- the Time-Sensitive Networking (TSN) [IEEE-802.1TSNTG] Task Group
expanded constituency from the industrial and vehicular markets. (TG), with a much-expanded constituency from the industrial and
vehicular markets.
Along with this expansion, the networks in consideration are becoming Along with this expansion, the networks considered here are becoming
larger and structured, requiring deterministic forwarding beyond the larger and structured, requiring deterministic forwarding beyond the
LAN boundaries. For instance, IACS segregates the network along the LAN boundaries. For instance, an IACS segregates the network along
broad lines of the Purdue Enterprise Reference Architecture (PERA) the broad lines of the Purdue Enterprise Reference Architecture
[ISA95], typically using deterministic local area networks for level (PERA) [ISA95], typically using deterministic LANs for Purdue level 2
2 control systems, whereas public infrastructures such as Electricity control systems, whereas public infrastructures such as electricity
Automation require deterministic properties over the Wide Area. The automation require deterministic properties over the wide area.
realization is now coming that the convergence of IT and Operational Implementers have come to realize that the convergence of IT and
Technology (OT) networks requires Layer-3, as well as Layer-2, Operation Technology (OT) networks requires Layer 3, as well as
capabilities. Layer 2, capabilities.
While the initial user base has focused almost entirely on Ethernet While the initial user base has focused almost entirely on Ethernet
physical media and Ethernet-based bridging protocol from several physical media and Ethernet-based bridging protocols from several
Standards Development Organizations, the need for Layer-3 expressed Standards Development Organizations (SDOs), the need for Layer 3, as
above, must not be confined to Ethernet and Ethernet-like media. expressed above, must not be confined to Ethernet and Ethernet-like
While such media must be encompassed by any useful Deterministic media. While such media must be encompassed by any useful
Networking (DetNet) Architecture, cooperation between IETF and other Deterministic Networking (DetNet) architecture, cooperation between
SDOs must not be limited to IEEE or IEEE 802. Furthermore, while the the IETF and other SDOs must not be limited to the IEEE or the
work completed and ongoing in other SDOs, and in IEEE 802 in IEEE 802 organizations. Furthermore, while both completed and
particular, provide an obvious starting point for a DetNet ongoing work in other SDOs, and in IEEE 802 in particular, provides
architecture, we must not assume that these other SDOs' work confines an obvious starting point for a DetNet architecture, we must not
the space in which the DetNet architecture progresses. assume that these other SDOs' work confines the space in which the
DetNet architecture progresses.
The properties of deterministic networks will have specific The properties of deterministic networks will have specific
requirements for the use of routed networks to support these requirements for the use of routed networks to support these
applications and a new model must be proposed to integrate applications, and a new model must be proposed to integrate this
determinism in IT technology. The proposed model should enable a determinism in IT implementations. The proposed model should enable
fully scheduled operation orchestrated by a central controller, and a fully scheduled operation orchestrated by a central controller and
may support a more distributed operation with probably lesser may support a more distributed operation with (probably lesser)
capabilities. In any fashion, the model should not compromise the capabilities. At any rate, the model should not compromise the
ability of a network to keep carrying the sorts of traffic that is ability of a network to keep carrying the sorts of traffic that is
already carried today in conjunction with new, more deterministic already carried today in conjunction with new, more deterministic
flows. Forward note: The DetNet Architecture flows. Note: "Deterministic Networking Architecture" [DetNet-Arch]
[I-D.ietf-detnet-architecture] is the document produced by the DetNet was produced by the DetNet Working Group to describe that model.
WG to describe that model.
At the time of this writing, the expectation is that once the At the time of this writing, it is expected that
abstract model is agreed upon, the IETF will specify the signaling
elements to be used to establish a path and the tagging elements to
be used identify the flows that are to be forwarded along that path.
The expectation is also that IETF will specify the necessary
protocols, or protocol additions, based on relevant IETF
technologies, to implement the selected model.
A desirable outcome of the work is the capability to establish a o once the abstract model is agreed upon, the IETF will specify
multi-hop path over the IP or MPLS network, for a particular flow (1) the signaling elements to be used to establish a path and
with given timing and precise throughput requirements, and carry this (2) the tagging elements to be used to identify the flows that are
to be forwarded along that path
o the IETF will specify the necessary protocols or protocol
additions, based on relevant IETF technologies, to implement the
selected model
A desirable outcome of the work is the ability to establish a
multi-hop path over the IP or MPLS network for a particular flow with
given timing and precise throughput requirements and to carry this
particular flow along the multi-hop path with such characteristics as particular flow along the multi-hop path with such characteristics as
low latency and ultra-low jitter, reordering and/or replication and low latency and ultra-low jitter, reordering and/or replication and
elimination of packets over non-congruent paths for a higher delivery elimination of packets over non-congruent paths for a higher delivery
ratio, and/or zero congestion loss, regardless of the amount of other ratio, and/or zero congestion loss, regardless of the amount of other
flows in the network. flows in the network.
Depending on the network capabilities and on the current state, Depending on the network capabilities and the current state, requests
requests to establish a path by an end-node or a network management to establish a path by an end node or a network management entity may
entity may be granted or rejected, an existing path may be moved or be granted or rejected, an existing path may be moved or removed, and
removed, and DetNet flows exceeding their contract may face packet DetNet flows exceeding their contract may face packet
declassification and drop. declassification and drop.
2. On Deterministic Networking 2. On Deterministic Networking
The Internet is not the only digital network that has grown The Internet is not the only digital network that has grown
dramatically over the last 30-40 years. Video and audio dramatically over the last 30-40 years. Video and audio
entertainment, and control systems for machinery, manufacturing entertainment, as well as control systems for machinery,
processes, and vehicles are also ubiquitous, and are now based almost manufacturing processes, and vehicles, are also ubiquitous and are
entirely on digital technologies. Over the past 10 years, engineers now based almost entirely on digital technologies. Over the past
in these fields have come to realize that significant advantages in 10 years, engineers in these fields have come to realize that
both cost and in the ability to accelerate growth can be obtained by significant advantages in both cost and the ability to accelerate
basing all of these disparate digital technologies on packet growth can be obtained by basing all of these disparate digital
networks. technologies on packet networks.
The goals of Deterministic Networking are to enable the migration of The goals of Deterministic Networking are to (1) enable the migration
applications with critical timing and reliability issues that of applications with critical timing and reliability issues that
currently use special-purpose fieldbus technologies (HDMI, CANbus, currently use special-purpose fieldbus technologies (High-Definition
ProfiBus, etc... even RS-232!) to packet technologies in general, and Multimedia Interface (HDMI), Controller Area Network (CAN bus),
the Internet Protocol in particular, and to support both these new PROFIBUS [PROFIBUS], etc. ... even RS-232!) to packet technologies in
applications, and existing packet network applications, over the same general and to IP in particular and (2) support both these new
physical network. In other words, a Deterministic Network is applications and existing packet network applications over the same
physical network. In other words, a deterministic network is
backwards compatible with (capable of transporting) statistically backwards compatible with (capable of transporting) statistically
multiplexed traffic while preserving the properties of the accepted multiplexed traffic while preserving the properties of the accepted
deterministic flows. deterministic flows.
The Deterministic Networking Use Cases [I-D.ietf-detnet-use-cases] [RFC8578] indicates that applications in multiple fields need some or
document indicates that applications in multiple fields need some or
all of a suite of features that includes: all of a suite of features that includes:
1. Time synchronization of all host and network nodes (routers and/ 1. Time synchronization of all host and network nodes (routers
or bridges), accurate to something between 10 nanoseconds and 10 and/or bridges), accurate to something between 10 nanoseconds and
microseconds, depending on the application. 10 microseconds, depending on the application.
2. Support for Deterministic packet flows that: 2. Support for deterministic packet flows that:
* Can be unicast or multicast; * Can be unicast or multicast.
* Need absolute guarantees of minimum and maximum latency end- * Need absolute guarantees of minimum and maximum latency
to-end across the network; sometimes a tight jitter is end to end across the network; sometimes a tight jitter is
required as well; required as well.
* Need a packet loss ratio beyond the classical range for a * Need a packet loss ratio beyond the classical range for a
particular medium, in the range of 10^-9 to 10^-12, or better, particular medium, in the range of 10^-9 to 10^-12 or better
on Ethernet, and in the order of 10^-5 in Wireless Sensor Mesh on Ethernet and on the order of 10^-5 in wireless sensor mesh
Networks; networks.
* Can, in total, absorb more than half of the network's * Can, in total, absorb more than half of the network's
available bandwidth (that is, massive over-provisioning is available bandwidth (that is, massive over-provisioning is
ruled out as a solution); ruled out as a solution).
* Cannot suffer throttling, congestion feedback, or any other * Cannot suffer throttling, congestion feedback, or any other
network-imposed transmission delay, although the flows can be network-imposed transmission delay, although the flows can be
meaningfully characterized either by a fixed, repeating meaningfully characterized by either (1) a fixed, repeating
transmission schedule, or by a maximum bandwidth and packet transmission schedule or (2) a maximum bandwidth and packet
size; size.
3. Multiple methods to schedule, shape, limit, and otherwise control 3. Multiple methods for scheduling, shaping, limiting, and otherwise
the transmission of critical packets at each hop through the controlling the transmission of critical packets at each hop
network data plane; through the network data plane.
4. Robust defenses against misbehaving hosts, routers, or bridges, 4. Robust defenses against misbehaving hosts, routers, or bridges,
both in the data and control planes, with guarantees that a in both the data plane and the control plane, with guarantees
critical flow within its guaranteed resources cannot be affected that a critical flow within its guaranteed resources cannot be
by other flows whatever the pressures on the network - more on affected by other flows, whatever the pressures on the network.
the specific threats against DetNet in the DetNet Security For more on the specific threats against DetNet, see
Considerations [I-D.ietf-detnet-security] document; "Deterministic Networking (DetNet) Security Considerations"
[DetNet-Security].
5. One or more methods to reserve resources in bridges and routers 5. One or more methods for reserving resources in bridges and
to carry these flows. routers to carry these flows.
Time synchronization techniques need not be addressed by an IETF Time-synchronization techniques need not be addressed by an IETF
Working Group; there are a number of standards available for this working group; there are a number of standards available for this
purpose, including IEEE 1588, IEEE 802.1AS, and more. purpose, including IEEE 1588 [IEEE-1588], IEEE 802.1AS [IEEE-8021AS],
and more.
The multicast, latency, loss ratio, and non-throttling needs are made The needs related to multicast, latency, loss ratio, and throttling
necessary by the algorithms employed by the applications. They are avoidance exist because the algorithms employed by the applications
not simply the transliteration of fieldbus needs to a packet-based demand it. They are not simply the transliteration of fieldbus needs
fieldbus simulation, but reflect fundamental mathematics of the to a packet-based fieldbus simulation; they also reflect fundamental
control of a physical system. mathematics of the control of a physical system.
With classical forwarding latency- and loss-sensitive packets across With classical forwarding of latency-sensitive and loss-sensitive
a network, interactions among different critical flows introduce packets across a network, interactions among different critical flows
fundamental uncertainties in delivery schedules. The details of the introduce fundamental uncertainties in delivery schedules. The
queuing, shaping, and scheduling algorithms employed by each bridge details of the queuing, shaping, and scheduling algorithms employed
or router to control the output sequence on a given port affect the by each bridge or router to control the output sequence on a given
detailed makeup of the output stream, e.g. how finely a given flow's port affect the detailed makeup of the output stream, e.g., how
packets are mixed among those of other flows. finely a given flow's packets are mixed among those of other flows.
This, in turn, has a strong effect on the buffer requirements, and This, in turn, has a strong effect on the buffer requirements, and
hence the latency guarantees deliverable, by the next bridge or hence the latency guarantees deliverable, by the next bridge or
router along the path. For this reason, the IEEE 802.1 Time- router along the path. For this reason, the IEEE 802.1 TSN TG has
Sensitive Networking Task Group has defined a new set of queuing, defined a new set of queuing, shaping, and scheduling algorithms that
shaping, and scheduling algorithms that enable each bridge or router enable each bridge or router to compute the exact number of buffers
to compute the exact number of buffers to be allocated for each flow to be allocated for each flow or class of flows.
or class of flows.
Robustness is a common need for networking protocols, but plays a Networking protocols commonly need robustness. Note that robustness
more important part in real-time control networks, where expensive plays a particularly important part in real-time control networks,
equipment, and even lives, can be lost due to misbehaving equipment. where expensive equipment, and even lives, can be lost due to
misbehaving equipment.
Reserving resources before packet transmission is the one fundamental Reserving resources before packet transmission is the one fundamental
shift in the behavior of network applications that is impossible to shift in the behavior of network applications that is impossible to
avoid. In the first place, a network cannot deliver finite latency avoid. In the first place, a network cannot deliver finite latency
and practically zero packet loss to an arbitrarily high offered load. and practically zero packet loss to an arbitrarily high offered load.
Secondly, achieving practically zero packet loss for unthrottled
Secondly, achieving practically zero packet loss for un-throttled (though bandwidth-limited) flows means that bridges and routers have
(though bandwidth limited) flows means that bridges and routers have to dedicate buffer resources to specific flows or classes of flows.
to dedicate buffer resources to specific flows or to classes of The requirements of each reservation have to be translated into the
flows. The requirements of each reservation have to be translated parameters that control each host's, bridge's, and router's queuing,
into the parameters that control each host's, bridge's, and router's shaping, and scheduling functions and delivered to the hosts,
queuing, shaping, and scheduling functions and delivered to the bridges, and routers.
hosts, bridges, and routers.
3. Problem Statement 3. Problem Statement
3.1. Supported topologies 3.1. Supported Topologies
In some use cases, the end point which run the application is In some use cases, the end point that runs the application is
involved in the deterministic networking operation, for instance by involved in the Deterministic Networking operation -- for instance,
controlling certain aspects of its throughput such as rate or precise by controlling certain aspects of its throughput, such as rate or
time of emission. In that case, the deterministic path is end-to-end precise time of emission. In such a case, the deterministic path is
from application host to application host. end to end from application host to application host.
On the other end, the deterministic portion of a path may be a tunnel On the other end, the deterministic portion of a path may be a tunnel
between an ingress and an egress router. In any case, routers and between an ingress point and an egress router. In any case, routers
switches in between should not need to be aware whether the path is and switches in between should not need to be aware of whether the
end-to-end or a tunnel. path is end to end or a tunnel.
While it is clear that DetNet does not aim at setting up While it is clear that DetNet does not aim to set up deterministic
deterministic paths over the global Internet, there is still a lack paths over the global Internet, there is still a lack of clarity
of clarity on the limits of a domain where a deterministic path can regarding the limits of a domain where a deterministic path can be
be set up. These limits may depend in the technology that is used to set up. These limits may depend on the technology that is used to
set the path up, whether it is centralized or distributed. set the path up, whether it is centralized or distributed.
3.2. Flow Characterization 3.2. Flow Characterization
Deterministic forwarding can only apply on flows with well-defined Deterministic forwarding can only apply to flows with such
characteristics such as periodicity and burstiness. Before a path well-defined characteristics as periodicity and burstiness. Before a
can be established to serve them, the expression of those path can be established to serve them, the expression of those
characteristics, and how the network can serve them, for instance in characteristics, and how the network can serve them (for instance, in
shaping and forwarding operations, must be specified. shaping and forwarding operations), must be specified.
3.3. Centralized Path Computation and Installation 3.3. Centralized Path Computation and Installation
A centralized routing model, such as provided with a Path Computation A centralized routing model, such as that provided with a Path
Element (PCE) (see [RFC4655]), enables global and per-flow Computation Element (PCE) (see [RFC4655]), enables global and
optimizations. The model is attractive but a number of issues are per-flow optimizations. This type of model is attractive, but a
left to be solved. In particular: number of issues remain to be solved -- in particular:
o whether and how the path computation can be installed by 1) an end o whether and how the path computation can be installed by
device or 2) a Network Management entity,
o and how the path is set up, either by installing state at each hop * an end device or
with a direct interaction between the forwarding device and the
PCE, or along a path by injecting a source-routed request at one * a network management entity
end of the path following classical Traffic Engineering (TE)
models. and
o how the path is set up -- either
* by installing state at each hop with a direct interaction
between the forwarding device and the PCE or
* along a path by injecting a source-routed request at one end of
the path, following classical Traffic Engineering (TE) models
To enable a centralized model, DetNet should produce a description of To enable a centralized model, DetNet should produce a description of
the high level interaction and data models to: the high-level interaction and data models to:
o report the topology and device capabilities to the central o report the topology and device capabilities to the central
controller; controller
o establish a direct interface between the centralized PCE to each o establish a direct interface between the centralized PCE and each
device under its control in order to enable a vertical signaling device under its control in order to enable vertical signaling
o request a path setup for a new flow with particular o request a path setup for a new flow with particular
characteristics over the service interface and control it through characteristics over the service interface and control it through
its life cycle; its life cycle
o support for life cycle management for a path o provide support for life-cycle management for a path
(instantiate/modify/update/delete) (instantiate/modify/update/delete)
o support for adaptability to cope with various events such as loss o provide support for adaptability to cope with such various events
of a link, etc... as loss of a link
o expose the status of the path to the end devices (UNI interface) o expose the status of the path to the end devices (User-Network
Interfaces (UNIs))
o provide additional reliability through redundancy, in particular o provide additional reliability through redundancy, particularly
with packet Packet Replication, Elimination and Ordering Functions with Packet Replication, Elimination, and Ordering Functions
(PREOF) where the former may generate an out-of-order delivery (PREOF), where redundant paths may deliver packets out of order
that may need to be corrected corrected by the latter; and PREOF may need to correct the ordering
o indicate the flows and packet sequences in-band with the flows, o indicate the flows and packet sequences in-band with the flows.
this is needed for flows that require PREOF in order to isolate This is needed for flows that require PREOF in order to isolate
duplicates and reorder in the end; duplicates and reorder packets at the end of the sequence
3.4. Distributed Path Setup 3.4. Distributed Path Setup
Whether a distributed alternative without a PCE can be valuable could Whether a distributed alternative without a PCE can be valuable could
be studied as well. Such an alternative could for instance inherit be studied as well. Such an alternative could, for instance, build
from the Resource ReSerVation Protocol [RFC3209] (RSVP-TE) flows. upon Resource Reservation Protocol - TE (RSVP-TE) flows [RFC3209].
But the focus of the work should be to deliver the centralized But the focus of the work should be to deliver the centralized
approach first. approach first.
To enable a RSVP-TE like functionality, the following steps would To enable functionality similar to that of RSVP-TE, the following
take place: steps would take place:
1. Neighbors and their capabilities are discovered and exposed to 1. Neighbors and their capabilities would be discovered and exposed
compute a path that fits the DetNet constraints, typically of to compute a path that would fit the DetNet constraints --
latency, time precision and resource availability. typically those of latency, time precision, and resource
availability.
2. A constrained path is calculated with an improved version of 2. A constrained path would be calculated with an improved version
Constrained Shortest Path First (CSPF) that is aware of DetNet. of Constrained Shortest Path First (CSPF) that is aware of
DetNet.
3. The path may be installed using a control protocol such as RSVP- 3. The path may be installed using a control protocol such as
TE, associated with flow identification, per-hop behavior such as RSVP-TE, extended to enable flow identification and install new
Packet Replication and Elimination, and blocked resources. In per-hop behavior such as Packet Replication, Elimination, and
that case, traffic flows can be transported through an MPLS-TE Ordering, and to reserve physical resources for the flow. In
that case, traffic flows could be transported through an MPLS-TE
tunnel, using the reserved resources for this flow at each hop. tunnel, using the reserved resources for this flow at each hop.
3.5. Duplicated data format 3.5. Duplicated Data Format
In some cases the duplication and elimination of packets over non- In some cases, the duplication and elimination of packets over
congruent paths is required to achieve a sufficiently high delivery non-congruent paths are required to achieve a sufficiently high
ratio to meet application needs. In these cases, a small number of delivery ratio to meet application needs. In these cases, a small
packet formats and supporting protocols are required (preferably, number of packet formats and supporting protocols are required
just one) to serialize the packets of a DetNet stream at one point in (preferably just one of each) to serialize the packets of a DetNet
the network, replicate them at one or more points in the network, and stream at one point in the network, replicate them at one or more
discard duplicates at one or more other points in the network, points in the network, and discard duplicates at one or more other
including perhaps the destination host. Using an existing solution points in the network, including perhaps the destination host. Using
would be preferable to inventing a new one. an existing solution would be preferable to inventing a new one.
4. Security Considerations 4. Security Considerations
Security in the context of Deterministic Networking has an added Security in the context of Deterministic Networking has an added
dimension; the time of delivery of a packet can be just as important dimension; the time of delivery of a packet can be just as important
as the contents of the packet, itself. A man-in-the-middle attack, as the contents of the packet itself. A man-in-the-middle attack,
for example, can impose, and then systematically adjust, additional for example, can impose and then systematically adjust additional
delays into a link, and thus disrupt or subvert a real-time delays into a link, and thus disrupt or subvert a real-time
application without having to crack any encryption methods employed. application without having to crack any encryption methods employed.
See [RFC7384] for an exploration of this issue in a related context. See [RFC7384] for an exploration of this issue in a related context.
Typical control networks today rely on complete physical isolation to Typical control networks today rely on complete physical isolation to
prevent rogue access to network resources. DetNet enables the prevent rogue access to network resources. DetNet enables the
virtualization of those networks over a converged IT/OT virtualization of those networks over a converged IT/OT
infrastructure. Doing so, DetNet introduces an additional risk that infrastructure. Doing so, DetNet introduces an additional risk of
flows interact and interfere with one another as they share physical flows interacting and interfering with one another as they share
resources such as Ethernet trunks and radio spectrum. The physical resources such as Ethernet trunks and the radio spectrum.
requirement is that there is no possible data leak from and into a The requirement is that there is no possible data leak from and into
deterministic flow, and in a more general fashion there is no a deterministic flow. Stated more generally, there is no possible
possible influence whatsoever from the outside on a deterministic influence whatsoever from the outside on a deterministic flow. The
flow. The expectation is that physical resources are effectively expectation is that physical resources are effectively associated
associated with a given flow at a given point of time. In that with a given flow at a given point in time. In that model, the
model, Time Sharing of physical resources becomes transparent to the time-sharing of physical resources becomes transparent to the
individual flows which have no clue whether the resources are used by individual flows, as these flows have no clue regarding whether or
other flows at other times. not the resources are used by other flows at other times.
The overall security of a deterministic system must cover: The overall security of a deterministic system must cover:
o the protection of the signaling protocol o the protection of the signaling protocol
o the authentication and authorization of the controlling nodes o the authentication and authorization of the controlling nodes,
including plug-and-play participating end systems. including plug-and-play participating end systems
o the identification and shaping of the flows o the identification and shaping of the flows
o the isolation of flows from leakage and other influences from any o the isolation of flows from leakage and other influences from any
activity sharing physical resources. activity sharing physical resources
The specific threats against DetNet are further discussed in the The specific threats against DetNet are further discussed in
DetNet Security Considerations [I-D.ietf-detnet-security] document. [DetNet-Security].
5. IANA Considerations 5. IANA Considerations
This document does not require an action from IANA. This document has no IANA actions.
6. Acknowledgments
The authors wish to thank Lou Berger, Pat Thaler, Jouni Korhonen,
Janos Farkas, Stewart Bryant, Andrew Malis, Ethan Grossman, Patrick
Wetterwald, Subha Dhesikan, Matthew Miller, Erik Nordmark, George
Swallow, Rodney Cummings, Ines Robles, Shwetha Bhandari, Rudy Klecka,
Anca Zamfir, David Black, Thomas Watteyne, Shitanshu Shah, Kiran
Makhijani, Craig Gunther, Warren Kumari, Wilfried Steiner, Marcel
Kiessling, Karl Weber, Alissa Cooper, and Benjamin Kaduk for their
various contributions to this work.
7. Informative References 6. Informative References
[I-D.ietf-detnet-architecture] [DetNet-Arch]
Finn, N., Thubert, P., Varga, B., and J. Farkas, Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", draft-ietf- "Deterministic Networking Architecture", Work in
detnet-architecture-09 (work in progress), October 2018. Progress, draft-ietf-detnet-architecture-13, May 2019.
[I-D.ietf-detnet-security] [DetNet-Security]
Mizrahi, T., Grossman, E., Hacker, A., Das, S., Dowdell, Mizrahi, T., Grossman, E., Ed., Hacker, A., Das, S.,
J., Austad, H., Stanton, K., and N. Finn, "Deterministic Dowdell, J., Austad, H., Stanton, K., and N. Finn,
Networking (DetNet) Security Considerations", draft-ietf- "Deterministic Networking (DetNet) Security
detnet-security-03 (work in progress), October 2018. Considerations", Work in Progress,
draft-ietf-detnet-security-04, March 2019.
[I-D.ietf-detnet-use-cases] [IEEE-1588]
Grossman, E., "Deterministic Networking Use Cases", draft- IEEE, "IEEE Standard for a Precision Clock Synchronization
ietf-detnet-use-cases-19 (work in progress), October 2018. Protocol for Networked Measurement and Control Systems",
IEEE Standard 1588-2008, <https://standards.ieee.org/
findstds/standard/1588-2008.html>.
[IEEE802.1TSNTG] [IEEE-802.1TSNTG]
IEEE Standards Association, "IEEE 802.1 Time-Sensitive IEEE Standards Association, "IEEE 802.1 Time-Sensitive
Networks Task Group", 2013, Networking Task Group",
<http://www.ieee802.org/1/pages/avbridges.html>. <http://www.ieee802.org/1/pages/avbridges.html>.
[ISA95] ANSI/ISA, "Enterprise-Control System Integration Part 1: [IEEE-8021AS]
Models and Terminology", 2000, IEEE, "IEEE Standard for Local and Metropolitan Area
<https://www.isa.org/isa95/>. Networks - Timing and Synchronization for Time-Sensitive
Applications in Bridged Local Area Networks",
IEEE 802.1AS-2011,
<http://www.ieee802.org/1/pages/802.1as.html>.
[ISA95] ANSI/ISA, "Enterprise-Control System Integration - Part 1:
Models and Terminology", <https://www.isa.org/isa95/>.
[PROFIBUS] IEC, "PROFIBUS Standard - DP Specification (IEC 61158
Type 3)", <https://www.profibus.com/>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/info/rfc3209>. <https://www.rfc-editor.org/info/rfc3209>.
[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation [RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path
Element (PCE)-Based Architecture", RFC 4655, Computation Element (PCE)-Based Architecture", RFC 4655,
DOI 10.17487/RFC4655, August 2006, DOI 10.17487/RFC4655, August 2006,
<https://www.rfc-editor.org/info/rfc4655>. <https://www.rfc-editor.org/info/rfc4655>.
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in [RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384, Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384,
October 2014, <https://www.rfc-editor.org/info/rfc7384>. October 2014, <https://www.rfc-editor.org/info/rfc7384>.
[RFC8578] Grossman, E., Ed., "Deterministic Networking Use Cases",
RFC 8578, DOI 10.17487/RFC8578, May 2019,
<https://www.rfc-editor.org/info/rfc8578>.
Acknowledgments
The authors wish to thank Lou Berger, Pat Thaler, Jouni Korhonen,
Janos Farkas, Stewart Bryant, Andrew Malis, Ethan Grossman, Patrick
Wetterwald, Subha Dhesikan, Matthew Miller, Erik Nordmark, George
Swallow, Rodney Cummings, Ines Robles, Shwetha Bhandari, Rudy Klecka,
Anca Zamfir, David Black, Thomas Watteyne, Shitanshu Shah, Kiran
Makhijani, Craig Gunther, Warren Kumari, Wilfried Steiner, Marcel
Kiessling, Karl Weber, Alissa Cooper, and Benjamin Kaduk for their
various contributions to this work.
Authors' Addresses Authors' Addresses
Norman Finn Norman Finn
Huawei Technologies Co. Ltd Huawei Technologies Co. Ltd
3755 Avocado Blvd. 3755 Avocado Blvd.
PMB 436 PMB 436
La Mesa, California 91941 La Mesa, California 91941
US United States of America
Phone: +1 925 980 6430 Phone: +1 925 980 6430
Email: norman.finn@mail01.huawei.com Email: norman.finn@mail01.huawei.com
Pascal Thubert Pascal Thubert
Cisco Systems Cisco Systems, Inc.
Village d'Entreprises Green Side Building D, 45 Allee des Ormes - BP1200
400, Avenue de Roumanille Mougins - Sophia Antipolis 06254
Batiment T3 France
Biot - Sophia Antipolis 06410
FRANCE
Phone: +33 497 232 634 Phone: +33 4 97 23 26 34
Email: pthubert@cisco.com Email: pthubert@cisco.com
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