draft-ietf-detnet-security-08.txt   draft-ietf-detnet-security-09.txt 
Internet Engineering Task Force T. Mizrahi Internet Engineering Task Force T. Mizrahi
Internet-Draft HUAWEI Internet-Draft HUAWEI
Intended status: Informational E. Grossman, Ed. Intended status: Informational E. Grossman, Ed.
Expires: August 6, 2020 DOLBY Expires: September 19, 2020 DOLBY
A. Hacker March 18, 2020
MISTIQ
S. Das
Applied Communication Sciences
J. Dowdell
Airbus Defence and Space
H. Austad
SINTEF Digital
N. Finn
HUAWEI
February 3, 2020
Deterministic Networking (DetNet) Security Considerations Deterministic Networking (DetNet) Security Considerations
draft-ietf-detnet-security-08 draft-ietf-detnet-security-09
Abstract Abstract
A deterministic network is one that can carry data flows for real- A DetNet (deterministic network) provides specific performance
time applications with extremely low data loss rates and bounded guarantees to its data flows, such as extremely low data loss rates
latency. Deterministic networks have been successfully deployed in and bounded latency. As a result, securing a DetNet implies that in
real-time operational technology (OT) applications for some years. addition to the best practice security measures taken for any
However, such networks are typically isolated from external access, mission-critical network, additional security measures may be needed
and thus the security threat from external attackers is low. IETF whose purpose is exclusively to secure the intended operation of
Deterministic Networking (DetNet) specifies a set of technologies these novel service properties. This document addresses specifically
that enable creation of deterministic networks on IP-based networks those security considerations, with the assumption that the reader is
of potentially wide area (on the scale of a corporate network) already familiar with network security best practices for the data
potentially bringing the OT network into contact with Information plane technologies underlying a given DetNet implementation. This
Technology (IT) traffic and security threats that lie outside of a document defines a threat model and a taxonomy of relevant attacks,
tightly controlled and bounded area (such as the internals of an including their potential impacts and mitigations.
aircraft). These DetNet technologies have not previously been
deployed together on a wide area IP-based network, and thus can A given DetNet may require securing only certain aspects of DetNet
present security considerations that may be new to IP-based wide area performance, for example extremely low data loss rates but not
network designers. This document, intended for use by DetNet network necessarily bounded latency. Therefore this document provides an
designers, provides insight into these security considerations. association of threats against various use cases by industry, and
also against the individual service properties as defined in the
DetNet Use Cases.
This document also addresses common DetNet security considerations
related to the IP and MPLS data plane technologies (the first to be
identified as supported by DetNet), thereby complementing the
Security Considerations sections of the various DetNet Data Plane
(and other) DetNet documents.
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on August 6, 2020. This Internet-Draft will expire on September 19, 2020.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Security Threats . . . . . . . . . . . . . . . . . . . . . . 6 3. Security Threats . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Threat Model . . . . . . . . . . . . . . . . . . . . . . 6 3.1. Threat Model . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Threat Analysis . . . . . . . . . . . . . . . . . . . . . 7 3.2. Threat Analysis . . . . . . . . . . . . . . . . . . . . . 7
3.2.1. Delay . . . . . . . . . . . . . . . . . . . . . . . . 7 3.2.1. Delay . . . . . . . . . . . . . . . . . . . . . . . . 7
3.2.1.1. Delay Attack . . . . . . . . . . . . . . . . . . 7 3.2.1.1. Delay Attack . . . . . . . . . . . . . . . . . . 7
3.2.2. DetNet Flow Modification or Spoofing . . . . . . . . 7 3.2.2. DetNet Flow Modification or Spoofing . . . . . . . . 7
3.2.3. Resource Segmentation or Slicing . . . . . . . . . . 7 3.2.3. Resource Segmentation or Slicing . . . . . . . . . . 7
3.2.3.1. Inter-segment Attack . . . . . . . . . . . . . . 7 3.2.3.1. Inter-segment Attack . . . . . . . . . . . . . . 8
3.2.4. Packet Replication and Elimination . . . . . . . . . 8 3.2.4. Packet Replication and Elimination . . . . . . . . . 8
3.2.4.1. Replication: Increased Attack Surface . . . . . . 8 3.2.4.1. Replication: Increased Attack Surface . . . . . . 8
3.2.4.2. Replication-related Header Manipulation . . . . . 8 3.2.4.2. Replication-related Header Manipulation . . . . . 8
3.2.5. Path Choice . . . . . . . . . . . . . . . . . . . . . 8 3.2.5. Path Choice . . . . . . . . . . . . . . . . . . . . . 9
3.2.5.1. Path Manipulation . . . . . . . . . . . . . . . . 8 3.2.5.1. Path Manipulation . . . . . . . . . . . . . . . . 9
3.2.5.2. Path Choice: Increased Attack Surface . . . . . . 9 3.2.5.2. Path Choice: Increased Attack Surface . . . . . . 9
3.2.6. Control Plane . . . . . . . . . . . . . . . . . . . . 9 3.2.6. Controller Plane . . . . . . . . . . . . . . . . . . 9
3.2.6.1. Control or Signaling Packet Modification . . . . 9 3.2.6.1. Control or Signaling Packet Modification . . . . 9
3.2.6.2. Control or Signaling Packet Injection . . . . . . 9 3.2.6.2. Control or Signaling Packet Injection . . . . . . 9
3.2.7. Scheduling or Shaping . . . . . . . . . . . . . . . . 9 3.2.7. Scheduling or Shaping . . . . . . . . . . . . . . . . 9
3.2.7.1. Reconnaissance . . . . . . . . . . . . . . . . . 9 3.2.7.1. Reconnaissance . . . . . . . . . . . . . . . . . 9
3.2.8. Time Synchronization Mechanisms . . . . . . . . . . . 9 3.2.8. Time Synchronization Mechanisms . . . . . . . . . . . 9
3.3. Threat Summary . . . . . . . . . . . . . . . . . . . . . 9 3.3. Threat Summary . . . . . . . . . . . . . . . . . . . . . 10
4. Security Threat Impacts . . . . . . . . . . . . . . . . . . . 10 4. Security Threat Impacts . . . . . . . . . . . . . . . . . . . 10
4.1. Delay-Attacks . . . . . . . . . . . . . . . . . . . . . . 13 4.1. Delay-Attacks . . . . . . . . . . . . . . . . . . . . . . 13
4.1.1. Data Plane Delay Attacks . . . . . . . . . . . . . . 13 4.1.1. Data Plane Delay Attacks . . . . . . . . . . . . . . 13
4.1.2. Control Plane Delay Attacks . . . . . . . . . . . . . 14 4.1.2. Controller Plane Delay Attacks . . . . . . . . . . . 14
4.2. Flow Modification and Spoofing . . . . . . . . . . . . . 14 4.2. Flow Modification and Spoofing . . . . . . . . . . . . . 14
4.2.1. Flow Modification . . . . . . . . . . . . . . . . . . 14 4.2.1. Flow Modification . . . . . . . . . . . . . . . . . . 14
4.2.2. Spoofing . . . . . . . . . . . . . . . . . . . . . . 14 4.2.2. Spoofing . . . . . . . . . . . . . . . . . . . . . . 14
4.2.2.1. Dataplane Spoofing . . . . . . . . . . . . . . . 14 4.2.2.1. Dataplane Spoofing . . . . . . . . . . . . . . . 14
4.2.2.2. Control Plane Spoofing . . . . . . . . . . . . . 15 4.2.2.2. Controller Plane Spoofing . . . . . . . . . . . . 15
4.3. Segmentation attacks (injection) . . . . . . . . . . . . 15 4.3. Segmentation attacks (injection) . . . . . . . . . . . . 15
4.3.1. Data Plane Segmentation . . . . . . . . . . . . . . . 15 4.3.1. Data Plane Segmentation . . . . . . . . . . . . . . . 15
4.3.2. Control Plane segmentation . . . . . . . . . . . . . 15 4.3.2. Controller Plane Segmentation . . . . . . . . . . . . 15
4.4. Replication and Elimination . . . . . . . . . . . . . . . 16 4.4. Replication and Elimination . . . . . . . . . . . . . . . 16
4.4.1. Increased Attack Surface . . . . . . . . . . . . . . 16 4.4.1. Increased Attack Surface . . . . . . . . . . . . . . 16
4.4.2. Header Manipulation at Elimination Bridges . . . . . 16 4.4.2. Header Manipulation at Elimination Routers . . . . . 16
4.5. Control or Signaling Packet Modification . . . . . . . . 16 4.5. Control or Signaling Packet Modification . . . . . . . . 16
4.6. Control or Signaling Packet Injection . . . . . . . . . . 16 4.6. Control or Signaling Packet Injection . . . . . . . . . . 16
4.7. Reconnaissance . . . . . . . . . . . . . . . . . . . . . 16 4.7. Reconnaissance . . . . . . . . . . . . . . . . . . . . . 16
4.8. Attacks on Time Sync Mechanisms . . . . . . . . . . . . . 17 4.8. Attacks on Time Sync Mechanisms . . . . . . . . . . . . . 17
4.9. Attacks on Path Choice . . . . . . . . . . . . . . . . . 17 4.9. Attacks on Path Choice . . . . . . . . . . . . . . . . . 17
5. Security Threat Mitigation . . . . . . . . . . . . . . . . . 17 5. Security Threat Mitigation . . . . . . . . . . . . . . . . . 17
5.1. Path Redundancy . . . . . . . . . . . . . . . . . . . . . 17 5.1. Path Redundancy . . . . . . . . . . . . . . . . . . . . . 17
5.2. Integrity Protection . . . . . . . . . . . . . . . . . . 17 5.2. Integrity Protection . . . . . . . . . . . . . . . . . . 17
5.3. DetNet Node Authentication . . . . . . . . . . . . . . . 18 5.3. DetNet Node Authentication . . . . . . . . . . . . . . . 18
5.4. Dummy Traffic Insertion . . . . . . . . . . . . . . . . . 18 5.4. Dummy Traffic Insertion . . . . . . . . . . . . . . . . . 19
5.5. Encryption . . . . . . . . . . . . . . . . . . . . . . . 19 5.5. Encryption . . . . . . . . . . . . . . . . . . . . . . . 19
5.5.1. Encryption Considerations for DetNet . . . . . . . . 19 5.5.1. Encryption Considerations for DetNet . . . . . . . . 19
5.6. Control and Signaling Message Protection . . . . . . . . 20 5.6. Control and Signaling Message Protection . . . . . . . . 20
5.7. Dynamic Performance Analytics . . . . . . . . . . . . . . 21 5.7. Dynamic Performance Analytics . . . . . . . . . . . . . . 21
5.8. Mitigation Summary . . . . . . . . . . . . . . . . . . . 21 5.8. Mitigation Summary . . . . . . . . . . . . . . . . . . . 21
6. Association of Attacks to Use Cases . . . . . . . . . . . . . 23 6. Association of Attacks to Use Cases . . . . . . . . . . . . . 23
6.1. Use Cases by Common Themes . . . . . . . . . . . . . . . 23 6.1. Use Cases by Common Themes . . . . . . . . . . . . . . . 23
6.1.1. Network Layer - AVB/TSN Ethernet . . . . . . . . . . 23 6.1.1. Sub-Network Layer . . . . . . . . . . . . . . . . . . 23
6.1.2. Central Administration . . . . . . . . . . . . . . . 24 6.1.2. Central Administration . . . . . . . . . . . . . . . 24
6.1.3. Hot Swap . . . . . . . . . . . . . . . . . . . . . . 24 6.1.3. Hot Swap . . . . . . . . . . . . . . . . . . . . . . 24
6.1.4. Data Flow Information Models . . . . . . . . . . . . 25 6.1.4. Data Flow Information Models . . . . . . . . . . . . 25
6.1.5. L2 and L3 Integration . . . . . . . . . . . . . . . . 25 6.1.5. L2 and L3 Integration . . . . . . . . . . . . . . . . 25
6.1.6. End-to-End Delivery . . . . . . . . . . . . . . . . . 25 6.1.6. End-to-End Delivery . . . . . . . . . . . . . . . . . 25
6.1.7. Proprietary Deterministic Ethernet Networks . . . . . 25 6.1.7. Proprietary Deterministic Ethernet Networks . . . . . 26
6.1.8. Replacement for Proprietary Fieldbuses . . . . . . . 26 6.1.8. Replacement for Proprietary Fieldbuses . . . . . . . 26
6.1.9. Deterministic vs Best-Effort Traffic . . . . . . . . 26 6.1.9. Deterministic vs Best-Effort Traffic . . . . . . . . 26
6.1.10. Deterministic Flows . . . . . . . . . . . . . . . . . 27 6.1.10. Deterministic Flows . . . . . . . . . . . . . . . . . 27
6.1.11. Unused Reserved Bandwidth . . . . . . . . . . . . . . 27 6.1.11. Unused Reserved Bandwidth . . . . . . . . . . . . . . 27
6.1.12. Interoperability . . . . . . . . . . . . . . . . . . 27 6.1.12. Interoperability . . . . . . . . . . . . . . . . . . 27
6.1.13. Cost Reductions . . . . . . . . . . . . . . . . . . . 27 6.1.13. Cost Reductions . . . . . . . . . . . . . . . . . . . 28
6.1.14. Insufficiently Secure Devices . . . . . . . . . . . . 28 6.1.14. Insufficiently Secure Devices . . . . . . . . . . . . 28
6.1.15. DetNet Network Size . . . . . . . . . . . . . . . . . 28 6.1.15. DetNet Network Size . . . . . . . . . . . . . . . . . 28
6.1.16. Multiple Hops . . . . . . . . . . . . . . . . . . . . 28 6.1.16. Multiple Hops . . . . . . . . . . . . . . . . . . . . 29
6.1.17. Level of Service . . . . . . . . . . . . . . . . . . 29 6.1.17. Level of Service . . . . . . . . . . . . . . . . . . 29
6.1.18. Bounded Latency . . . . . . . . . . . . . . . . . . . 29 6.1.18. Bounded Latency . . . . . . . . . . . . . . . . . . . 29
6.1.19. Low Latency . . . . . . . . . . . . . . . . . . . . . 30 6.1.19. Low Latency . . . . . . . . . . . . . . . . . . . . . 30
6.1.20. Bounded Jitter (Latency Variation) . . . . . . . . . 30 6.1.20. Bounded Jitter (Latency Variation) . . . . . . . . . 30
6.1.21. Symmetrical Path Delays . . . . . . . . . . . . . . . 30 6.1.21. Symmetrical Path Delays . . . . . . . . . . . . . . . 30
6.1.22. Reliability and Availability . . . . . . . . . . . . 30 6.1.22. Reliability and Availability . . . . . . . . . . . . 31
6.1.23. Redundant Paths . . . . . . . . . . . . . . . . . . . 31 6.1.23. Redundant Paths . . . . . . . . . . . . . . . . . . . 31
6.1.24. Security Measures . . . . . . . . . . . . . . . . . . 31 6.1.24. Security Measures . . . . . . . . . . . . . . . . . . 31
6.2. Attack Types by Use Case Common Theme . . . . . . . . . . 31 6.2. Attack Types by Use Case Common Theme . . . . . . . . . . 31
6.3. Security Considerations for OAM Traffic . . . . . . . . . 34 6.3. Security Considerations for OAM Traffic . . . . . . . . . 34
7. DetNet Technology-Specific Threats . . . . . . . . . . . . . 34 7. DetNet Technology-Specific Threats . . . . . . . . . . . . . 34
7.1. IP . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 7.1. IP . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
7.2. MPLS . . . . . . . . . . . . . . . . . . . . . . . . . . 36 7.2. MPLS . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 37 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 37
9. Security Considerations . . . . . . . . . . . . . . . . . . . 37 9. Security Considerations . . . . . . . . . . . . . . . . . . . 37
10. Informative References . . . . . . . . . . . . . . . . . . . 37 10. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 37
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 39 11. Informative References . . . . . . . . . . . . . . . . . . . 37
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 40
1. Introduction 1. Introduction
A deterministic network is one that can carry data flows for real-
time applications with extremely low data loss rates and bounded
latency. Deterministic networks have been successfully deployed in
real-time operational technology (OT) applications for some years.
However, such networks are typically isolated from external access,
and thus the security threat from external attackers is low. IETF
Deterministic Networking (DetNet) specifies a set of technologies
that enable creation of deterministic networks on IP-based networks
of potentially wide area (on the scale of a corporate network)
potentially bringing the OT network into contact with Information
Technology (IT) traffic and security threats that lie outside of a
tightly controlled and bounded area (such as the internals of an
aircraft). These DetNet technologies have not previously been
deployed together on a wide area IP-based network, and thus can
present security considerations that may be new to IP-based wide area
network designers. This document, intended for use by DetNet network
designers, provides insight into these security considerations.
Security is of particularly high importance in DetNet networks Security is of particularly high importance in DetNet networks
because many of the use cases which are enabled by DetNet [RFC8578] because many of the use cases which are enabled by DetNet [RFC8578]
include control of physical devices (power grid components, include control of physical devices (power grid components,
industrial controls, building controls) which can have high industrial controls, building controls) which can have high
operational costs for failure, and present potentially attractive operational costs for failure, and present potentially attractive
targets for cyber-attackers. targets for cyber-attackers.
This situation is even more acute given that one of the goals of This situation is even more acute given that one of the goals of
DetNet is to provide a "converged network", i.e. one that includes DetNet is to provide a "converged network", i.e. one that includes
both IT traffic and OT traffic, thus exposing potentially sensitive both IT traffic and OT traffic, thus exposing potentially sensitive
skipping to change at page 4, line 47 skipping to change at page 5, line 15
because they were under a separate control system or otherwise because they were under a separate control system or otherwise
isolated from the IT network, for example [ARINC664P7]). Security isolated from the IT network, for example [ARINC664P7]). Security
considerations for OT networks are not a new area, and there are many considerations for OT networks are not a new area, and there are many
OT networks today that are connected to wide area networks or the OT networks today that are connected to wide area networks or the
Internet; this document focuses on the issues that are specific to Internet; this document focuses on the issues that are specific to
the DetNet technologies and use cases. the DetNet technologies and use cases.
Given the above considerations, securing a DetNet starts with a Given the above considerations, securing a DetNet starts with a
scrupulously well-designed and well-managed engineered network scrupulously well-designed and well-managed engineered network
following industry best practices for security at both the data plane following industry best practices for security at both the data plane
and control plane; this is the assumed starting point for the and controller plane; this is the assumed starting point for the
considerations discussed herein. In this context we view the network considerations discussed herein. In this context we view the network
design and managment aspects of network security as being primarily design and managment aspects of network security as being primarily
concerned with denial-of service prevention by ensuring that DetNet concerned with denial-of service prevention by ensuring that DetNet
traffic goes where it's supposed to and that an external attacker traffic goes where it's supposed to and that an external attacker
can't inject traffic that disrupts the DetNet's delivery timing can't inject traffic that disrupts the DetNet's delivery timing
assurance. The time-specific aspects of DetNet security presented assurance. The time-specific aspects of DetNet security presented
here take up where the design and management aspects leave off. here take up where the design and management aspects leave off.
The security requirements for any given DetNet network are The exact security requirements for any given DetNet network are
necessarily specific to the use cases handled by that network. Thus necessarily specific to the use cases handled by that network. Thus
the reader is assumed to be familiar with the specific security the reader is assumed to be familiar with the specific security
requirements of their use cases, for example those outlined in the requirements of their use cases, for example those outlined in the
DetNet Use Cases [RFC8578] and the Security Considerations sections DetNet Use Cases [RFC8578] and the Security Considerations sections
of the DetNet documents applicable to the network technologies in of the DetNet documents applicable to the network technologies in
use, for example [I-D.ietf-detnet-ip]). use, for example [I-D.ietf-detnet-ip]). A general introduction to
the DetNet architecture can be found in [RFC8655] and it is also
recommended to be familiar with the Data Plane model
[I-D.ietf-detnet-data-plane-framework] and Flow Information Model
[I-D.ietf-detnet-flow-information-model].
The DetNet technologies include ways to: The DetNet technologies include ways to:
o Reserve data plane resources for DetNet flows in some or all of o Assign data plane resources for DetNet flows in some or all of the
the intermediate nodes (e.g. bridges or routers) along the path of intermediate nodes (routers) along the path of the flow
the flow
o Provide explicit routes for DetNet flows that do not rapidly o Provide explicit routes for DetNet flows that do not rapidly
change with the network topology change with the network topology
o Distribute data from DetNet flow packets over time and/or space to o Distribute data from DetNet flow packets over time and/or space to
ensure delivery of each packet's data' in spite of the loss of a ensure delivery of each packet's data' in spite of the loss of a
path path
This document includes sections on threat modeling and analysis, This document includes sections on threat modeling and analysis,
threat impact and mitigation, and the association of attacks with use threat impact and mitigation, and the association of attacks with use
cases based on the Use Case Common Themes section of the DetNet Use cases based on the Use Case Common Themes section of the DetNet Use
Cases [RFC8578]. Cases.
2. Abbreviations 2. Abbreviations
IT Information technology (the application of computers to IT Information technology (the application of computers to
store, study, retrieve, transmit, and manipulate data or information, store, study, retrieve, transmit, and manipulate data or information,
often in the context of a business or other enterprise - Wikipedia). often in the context of a business or other enterprise - Wikipedia).
OT Operational Technology (the hardware and software OT Operational Technology (the hardware and software
dedicated to detecting or causing changes in physical processes dedicated to detecting or causing changes in physical processes
through direct monitoring and/or control of physical devices such as through direct monitoring and/or control of physical devices such as
valves, pumps, etc. - Wikipedia) valves, pumps, etc. - Wikipedia)
MITM Man in the Middle MITM Man in the Middle
SN Sequence Number
STRIDE Addresses risk and severity associated with threat
categories: Spoofing identity, Tampering with data, Repudiation,
Information disclosure, Denial of service, Elevation of privilege.
DREAD Compares and prioritizes risk represented by these threat
categories: Damage potential, Reproducibility, Exploitability, how
many Affected users, Discoverability.
PTP Precision Time Protocol [IEEE1588]
3. Security Threats 3. Security Threats
This section presents a threat model, and analyzes the possible This section presents a threat model, and analyzes the possible
threats in a DetNet-enabled network. The threats considered in this threats in a DetNet-enabled network. The threats considered in this
section are independent of any specific technologies used to section are independent of any specific technologies used to
implement the DetNet; Section 7) considers attacks that are implement the DetNet; Section 7) considers attacks that are
associated with the DetNet technologies encompassed by associated with the DetNet technologies encompassed by
[I-D.ietf-detnet-data-plane-framework]. [I-D.ietf-detnet-data-plane-framework].
We distinguish control plane threats from data plane threats. The We distinguish controller plane threats from data plane threats. The
attack surface may be the same, but the types of attacks as well as attack surface may be the same, but the types of attacks as well as
the motivation behind them, are different. For example, a delay the motivation behind them, are different. For example, a delay
attack is more relevant to data plane than to control plane. There attack is more relevant to data plane than to controller plane.
is also a difference in terms of security solutions: the way you There is also a difference in terms of security solutions: the way
secure the data plane is often different than the way you secure the you secure the data plane is often different than the way you secure
control plane. the controller plane.
3.1. Threat Model 3.1. Threat Model
The threat model used in this memo is based on the threat model of The threat model used in this memo is based on the threat model of
Section 3.1 of [RFC7384]. This model classifies attackers based on Section 3.1 of [RFC7384]. This model classifies attackers based on
two criteria: two criteria:
o Internal vs. external: internal attackers either have access to a o Internal vs. external: internal attackers either have access to a
trusted segment of the network or possess the encryption or trusted segment of the network or possess the encryption or
authentication keys. External attackers, on the other hand, do authentication keys. External attackers, on the other hand, do
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o Man in the Middle (MITM) vs. packet injector: MITM attackers are o Man in the Middle (MITM) vs. packet injector: MITM attackers are
located in a position that allows interception and modification of located in a position that allows interception and modification of
in-flight protocol packets, whereas a traffic injector can only in-flight protocol packets, whereas a traffic injector can only
attack by generating protocol packets. attack by generating protocol packets.
Care has also been taken to adhere to Section 5 of [RFC3552], both Care has also been taken to adhere to Section 5 of [RFC3552], both
with respect to which attacks are considered out-of-scope for this with respect to which attacks are considered out-of-scope for this
document, but also which are considered to be the most common threats document, but also which are considered to be the most common threats
(explored further in Section 3.2. Most of the direct threats to (explored further in Section 3.2. Most of the direct threats to
DetNet are Active attacks, but it is highly suggested that DetNet DetNet are active attacks, but it is highly suggested that DetNet
application developers take appropriate measures to protect the application developers take appropriate measures to protect the
content of the streams from passive attacks. content of the DetNet flows from passive attacks.
DetNet-Service, one of the service scenarios described in DetNet-Service, one of the service scenarios described in
[I-D.varga-detnet-service-model], is the case where a service [I-D.varga-detnet-service-model], is the case where a service
connects DetNet networking islands, i.e. two or more otherwise connects DetNet networking islands, i.e. two or more otherwise
independent DetNet network domains are connected via a link that is independent DetNet network domains are connected via a link that is
not intrinsically part of either network. This implies that there not intrinsically part of either network. This implies that there
could be DetNet traffic flowing over a non-DetNet link, which may could be DetNet traffic flowing over a non-DetNet link, which may
provide an attacker with an advantageous opportunity to tamper with provide an attacker with an advantageous opportunity to tamper with
DetNet traffic. The security properties of non-DetNet links are DetNet traffic. The security properties of non-DetNet links are
outside of the scope of DetNet Security, but it should be noted that outside of the scope of DetNet Security, but it should be noted that
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An attacker can modify some header fields of en route packets in a An attacker can modify some header fields of en route packets in a
way that causes the DetNet flow identification mechanisms to way that causes the DetNet flow identification mechanisms to
misclassify the flow. Alternatively, the attacker can inject traffic misclassify the flow. Alternatively, the attacker can inject traffic
that is tailored to appear as if it belongs to a legitimate DetNet that is tailored to appear as if it belongs to a legitimate DetNet
flow. The potential consequence is that the DetNet flow resource flow. The potential consequence is that the DetNet flow resource
allocation cannot guarantee the performance that is expected when the allocation cannot guarantee the performance that is expected when the
flow identification works correctly. flow identification works correctly.
3.2.3. Resource Segmentation or Slicing 3.2.3. Resource Segmentation or Slicing
3.2.3.1. Inter-segment Attack 3.2.3.1. Inter-segment Attack
An attacker can inject traffic, consuming network device resources, An attacker can inject traffic that will consume network resources
thereby affecting DetNet flows. This can be performed using non- such that it affects DetNet flows. This can be performed using non-
DetNet traffic that affects DetNet traffic, or by using DetNet DetNet traffic that indirectly affects DetNet traffic (hardware
traffic from one DetNet flow that affects traffic from different resource exhaustion), or by using DetNet traffic from one DetNet flow
DetNet flows. that directly affects traffic from different DetNet flows.
3.2.4. Packet Replication and Elimination 3.2.4. Packet Replication and Elimination
3.2.4.1. Replication: Increased Attack Surface 3.2.4.1. Replication: Increased Attack Surface
Redundancy is intended to increase the robustness and survivability Redundancy is intended to increase the robustness and survivability
of DetNet flows, and replication over multiple paths can potentially of DetNet flows, and replication over multiple paths can potentially
mitigate an attack that is limited to a single path. However, the mitigate an attack that is limited to a single path. However, the
fact that packets are replicated over multiple paths increases the fact that packets are replicated over multiple paths increases the
attack surface of the network, i.e., there are more points in the attack surface of the network, i.e., there are more points in the
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access to a single path can cause packets from other paths to be access to a single path can cause packets from other paths to be
dropped, thus compromising some of the advantage of path dropped, thus compromising some of the advantage of path
redundancy. redundancy.
o Flow hijacking - an attacker can hijack a DetNet flow with access o Flow hijacking - an attacker can hijack a DetNet flow with access
to a single path by systematically replacing the SNs on the given to a single path by systematically replacing the SNs on the given
path with higher SN values. For example, an attacker can replace path with higher SN values. For example, an attacker can replace
every SN value S with a higher value S+C, where C is a constant every SN value S with a higher value S+C, where C is a constant
integer. Thus, the attacker creates a false illusion that the integer. Thus, the attacker creates a false illusion that the
attacked path has the lowest delay, causing all packets from other attacked path has the lowest delay, causing all packets from other
paths to be eliminated. Once the flow is hijacked the attacker paths to be eliminated in favor of the attacked path. Once the
can either replace en route packets with malicious packets, or flow from the compromised path is favored by the elminating
bridge, the flow is hijacked by the attacker. It is now posible
to either replace en route packets with malicious packets, or
simply injecting errors, causing the packets to be dropped at simply injecting errors, causing the packets to be dropped at
their destination. their destination.
3.2.5. Path Choice 3.2.5. Path Choice
3.2.5.1. Path Manipulation 3.2.5.1. Path Manipulation
An attacker can maliciously change, add, or remove a path, thereby An attacker can maliciously change, add, or remove a path, thereby
affecting the corresponding DetNet flows that use the path. affecting the corresponding DetNet flows that use the path.
3.2.5.2. Path Choice: Increased Attack Surface 3.2.5.2. Path Choice: Increased Attack Surface
One of the possible consequences of a path manipulation attack is an One of the possible consequences of a path manipulation attack is an
increased attack surface. Thus, when the attack described in the increased attack surface. Thus, when the attack described in the
previous subsection is implemented, it may increase the potential of previous subsection is implemented, it may increase the potential of
other attacks to be performed. other attacks to be performed.
3.2.6. Control Plane 3.2.6. Controller Plane
3.2.6.1. Control or Signaling Packet Modification 3.2.6.1. Control or Signaling Packet Modification
An attacker can maliciously modify en route control packets in order An attacker can maliciously modify en route control packets in order
to disrupt or manipulate the DetNet path/resource allocation. to disrupt or manipulate the DetNet path/resource allocation.
3.2.6.2. Control or Signaling Packet Injection 3.2.6.2. Control or Signaling Packet Injection
An attacker can maliciously inject control packets in order to An attacker can maliciously inject control packets in order to
disrupt or manipulate the DetNet path/resource allocation. disrupt or manipulate the DetNet path/resource allocation.
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4.1. Delay-Attacks 4.1. Delay-Attacks
4.1.1. Data Plane Delay Attacks 4.1.1. Data Plane Delay Attacks
Note that 'delay attack' also includes the possibility of a 'negative Note that 'delay attack' also includes the possibility of a 'negative
delay' or early arrival of a packet, or possibly adversely changing delay' or early arrival of a packet, or possibly adversely changing
the timestamp value. the timestamp value.
Delayed messages in a DetNet link can result in the same behavior as Delayed messages in a DetNet link can result in the same behavior as
dropped messages in ordinary networks as the services attached to the dropped messages in ordinary networks as the services attached to the
stream has strict deterministic requirements. DetNet flow have strict deterministic requirements.
For a single path scenario, disruption is a real possibility, whereas For a single path scenario, disruption is a real possibility, whereas
in a multipath scenario, large delays or instabilities in one stream in a multipath scenario, large delays or instabilities in one DetNet
can lead to increased buffer and CPU resources on the elimination flow can lead to increased buffer and processor resources at the
bridge. eliminating router.
A data-plane delay attack on a system controlling substantial moving A data-plane delay attack on a system controlling substantial moving
devices, for example in industrial automation, can cause physical devices, for example in industrial automation, can cause physical
damage. For example, if the network promises a bounded latency of damage. For example, if the network promises a bounded latency of
2ms for a flow, yet the machine receives it with 5ms latency, the 2ms for a flow, yet the machine receives it with 5ms latency, the
machine's control loop can become unstable. machine's control loop can become unstable.
4.1.2. Control Plane Delay Attacks 4.1.2. Controller Plane Delay Attacks
In and of itself, this is not directly a threat to the DetNet In and of itself, this is not directly a threat to the DetNet
service, but the effects of delaying control messages can have quite service, but the effects of delaying control messages can have quite
adverse effects later. adverse effects later.
o Delayed tear-down can lead to resource leakage, which in turn can o Delayed tear-down can lead to resource leakage, which in turn can
result in failure to allocate new streams finally giving rise to a result in failure to allocate new DetNet flows, finally giving
denial of service attack. rise to a denial of service attack.
o Failure to deliver, or severely delaying, signalling messages o Failure to deliver, or severely delaying, controller plane
adding an end-point to a multicast-group will prevent the new EP messages adding an endpoint to a multicast-group will prevent the
from receiving expected frames thus disrupting expected behavior. new endpoint from receiving expected frames thus disrupting
expected behavior.
o Delaying messages removing an EP from a group can lead to loss of o Delaying messages removing an endpoint from a group can lead to
privacy as the EP will continue to receive messages even after it loss of privacy as the endpoint will continue to receive messages
is supposedly removed. even after it is supposedly removed.
4.2. Flow Modification and Spoofing 4.2. Flow Modification and Spoofing
4.2.1. Flow Modification 4.2.1. Flow Modification
If the contents of a packet header or body can be modified by the If the contents of a packet header or body can be modified by the
attacker, this can cause the packet to be routed incorrectly or attacker, this can cause the packet to be routed incorrectly or
dropped, or the payload to be corrupted or subtly modified. dropped, or the payload to be corrupted or subtly modified.
4.2.2. Spoofing 4.2.2. Spoofing
4.2.2.1. Dataplane Spoofing 4.2.2.1. Dataplane Spoofing
Spoofing dataplane messages can result in increased resource Spoofing dataplane messages can result in increased resource
consumptions on the bridges throughout the network as it will consumptions on the routers throughout the network as it will
increase buffer usage and CPU utilization. This can lead to resource increase buffer usage and processor utilization. This can lead to
exhaustion and/or increased delay. resource exhaustion and/or increased delay.
If the attacker manages to create valid headers, the false messages If the attacker manages to create valid headers, the false messages
can be forwarded through the network, using part of the allocated can be forwarded through the network, using part of the allocated
bandwidth. This in turn can cause legitimate messages to be dropped bandwidth. This in turn can cause legitimate messages to be dropped
when the budget has been exhausted. when the resource budget has been exhausted.
Finally, the endpoint will have to deal with invalid messages being Finally, the endpoint will have to deal with invalid messages being
delivered to the endpoint instead of (or in addition to) a valid delivered to the endpoint instead of (or in addition to) a valid
message. message.
4.2.2.2. Control Plane Spoofing 4.2.2.2. Controller Plane Spoofing
A successful control plane spoofing-attack will potentionally have A successful controller plane spoofing-attack will potentionally have
adverse effects. It can do virtually anything from: adverse effects. It can do virtually anything from:
o modifying existing streams by changing the available bandwidth o modifying existing DetNet flows by changing the available
bandwidth
o add or remove endpoints from a stream o add or remove endpoints from a DetNet flow
o drop streams completly o drop DetNet flows completely
o falsely create new streams (exhaust the systems resources, or to o falsely create new DetNet flows (exhaust the systems resources, or
enable streams outside the Network engineer's control) to enable DetNet flows that are outside the Network Engineer's
control)
4.3. Segmentation attacks (injection) 4.3. Segmentation attacks (injection)
4.3.1. Data Plane Segmentation 4.3.1. Data Plane Segmentation
Injection of false messages in a DetNet stream could lead to Injection of false messages in a DetNet flow could lead to exhaustion
exhaustion of the available bandwidth for a stream if the bridges of the available bandwidth for that flow if the routers attribute
accounts false messages to the stream's budget. these false messages to that flow's budget.
In a multipath scenario, injected messages will cause increased CPU
utilization in elimination bridges. If enough paths are subject to
malicious injection, the legitimate messages can be dropped.
Likewise it can cause an increase in buffer usage. In total, it will
consume more resources in the bridges than normal, giving rise to a
resource exhaustion attack on the bridges.
If a stream is interrupted, the end application will be affected by In a multipath scenario, injected messages will cause increased
what is now a non-deterministic stream. processor utilization in elimination routers. If enough paths are
subject to malicious injection, the legitimate messages can be
dropped. Likewise it can cause an increase in buffer usage. In
total, it will consume more resources in the routers than normal,
giving rise to a resource exhaustion attack on the routers.
4.3.2. Control Plane segmentation If a DetNet flow is interrupted, the end application will be affected
by what is now a non-deterministic flow.
A successful Control Plane segmentation attack control messages to be 4.3.2. Controller Plane Segmentation
interpreted by nodes in the network, unbeknownst to the central
controller or the network engineer. This has the potential to create
o new streams (exhausting resources) In a successful controller plane segmentation attack, control
messages are acted on by nodes in the network, unbeknownst to the
central controller or the network engineer. This has the potential
to:
o drop existing (denial of service) o create new DetNet flows (exhausting resources)
o drop existing DetNet flows (denial of service)
o add/remove end-stations to a multicast group (loss of privacy) o add/remove end-stations to a multicast group (loss of privacy)
o modify the stream attributes (affecting available bandwidth o modify the DetNet flow attributes (affecting available bandwidth
4.4. Replication and Elimination 4.4. Replication and Elimination
The Replication and Elimination is relevant only to Data Plane The Replication and Elimination is relevant only to Data Plane
messages as Signalling is not subject to multipath routing. messages as controller plane messages are not subject to multipath
routing.
4.4.1. Increased Attack Surface 4.4.1. Increased Attack Surface
Covered briefly in Section 4.3 Covered briefly in Section 4.3
4.4.2. Header Manipulation at Elimination Bridges 4.4.2. Header Manipulation at Elimination Routers
Covered briefly in Section 4.3 Covered briefly in Section 4.3
4.5. Control or Signaling Packet Modification 4.5. Control or Signaling Packet Modification
If the control plane packets are subject to manipulation undetected, If control packets are subject to manipulation undetected, the
the network can be severely compromised. network can be severely compromised.
4.6. Control or Signaling Packet Injection 4.6. Control or Signaling Packet Injection
If an attacker can inject control plane packets undetected, the If an attacker can inject control packets undetected, the network can
network can be severely compromised. be severely compromised.
4.7. Reconnaissance 4.7. Reconnaissance
Of all the attacks, this is one of the most difficult to detect and Of all the attacks, this is one of the most difficult to detect and
counter. Often, an attacker will start out by observing the traffic counter. Often, an attacker will start out by observing the traffic
going through the network and use the knowledge gathered in this going through the network and use the knowledge gathered in this
phase to mount future attacks. phase to mount future attacks.
The attacker can, at their leisure, observe over time all aspects of The attacker can, at their leisure, observe over time all aspects of
the messaging and signalling, learning the intent and purpose of all the messaging and signalling, learning the intent and purpose of all
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locate the source of a MITM attacker. locate the source of a MITM attacker.
A delay modulation attack could result in extensively exercising A delay modulation attack could result in extensively exercising
parts of the code that wouldn't normally be extensively exercised parts of the code that wouldn't normally be extensively exercised
and thus might expose flaws in the system that might otherwise not and thus might expose flaws in the system that might otherwise not
be exposed. be exposed.
5.2. Integrity Protection 5.2. Integrity Protection
Description Description
An integrity protection mechanism, such as a Hash-based Message An integrity protection mechanism, such as a Hash-based Message
Authentication Code (HMAC) can be used to mitigate modification Authentication Code (HMAC) can be used to mitigate modification
attacks on IP packets. Integrity protection in the control plane attacks on IP packets. Integrity protection in the controller
is discussed in Section 5.6. plane is discussed in Section 5.6.
Packet Sequence Number Integrity Considerations Packet Sequence Number Integrity Considerations
The use of PREOF in a DetNet implementation implies the use of a The use of PREOF in a DetNet implementation implies the use of a
sequence number for each packet. There is a trust relationship sequence number for each packet. There is a trust relationship
between the device that adds the sequence number and the device between the device that adds the sequence number and the device
that removes the sequence number. The sequence number may be end- that removes the sequence number. The sequence number may be end-
to-end source to destination, or may be added/deleted by network to-end source to destination, or may be added/deleted by network
edge devices. The adder and remover(s) have the trust edge devices. The adder and remover(s) have the trust
relationship because they are the ones that ensure that the relationship because they are the ones that ensure that the
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DetNet flows can in principle be forwarded in encrypted form at DetNet flows can in principle be forwarded in encrypted form at
the DetNet layer, however, regarding encryption of IP headers see the DetNet layer, however, regarding encryption of IP headers see
Section 7. Section 7.
Alternatively, if the payload is end-to-end encrypted at the Alternatively, if the payload is end-to-end encrypted at the
application layer, the DetNet nodes should not have any need to application layer, the DetNet nodes should not have any need to
inspect the payload itself, and thus the DetNet implementation can inspect the payload itself, and thus the DetNet implementation can
be data-agnostic. be data-agnostic.
Encryption can also be applied at the subnet layer, for example
for Ethernet using MACSec, as noted in Section 7.
Related attacks Related attacks
Encryption can be used to mitigate recon attacks (Section 3.2.7). Encryption can be used to mitigate recon attacks (Section 3.2.7).
However, for a DetNet network to give differentiated quality of However, for a DetNet network to give differentiated quality of
service on a flow-by-flow basis, the network must be able to service on a flow-by-flow basis, the network must be able to
identify the flows individually. This implies that in a recon identify the flows individually. This implies that in a recon
attack the attacker may also be able to track individual flows to attack the attacker may also be able to track individual flows to
learn more about the system. learn more about the system.
5.5.1. Encryption Considerations for DetNet 5.5.1. Encryption Considerations for DetNet
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the latency calculations. the latency calculations.
5.6. Control and Signaling Message Protection 5.6. Control and Signaling Message Protection
Description Description
Control and sigaling messages can be protected using Control and sigaling messages can be protected using
authentication and integrity protection mechanisms. authentication and integrity protection mechanisms.
Related attacks Related attacks
These mechanisms can be used to mitigate various attacks on the These mechanisms can be used to mitigate various attacks on the
control plane, as described in Section 3.2.6, Section 3.2.8 and controller plane, as described in Section 3.2.6, Section 3.2.8 and
Section 3.2.5. Section 3.2.5.
5.7. Dynamic Performance Analytics 5.7. Dynamic Performance Analytics
Description Description
The expectation is that the network will have a way to monitor to The expectation is that the network will have a way to monitor to
detect if timing guarantees are not being met, and a way to alert detect if timing guarantees are not being met, and a way to alert
the control plane in that event. Information about the network the controller plane in that event. Information about the network
performance can be gathered in real-time in order to detect performance can be gathered in real-time in order to detect
anomalies and unusual behavior that may be the symptom of a anomalies and unusual behavior that may be the symptom of a
security attack. The gathered information can be based, for security attack. The gathered information can be based, for
example, on per-flow counters, bandwidth measurement, and example, on per-flow counters, bandwidth measurement, and
monitoring of packet arrival times. Unusual behavior or monitoring of packet arrival times. Unusual behavior or
potentially malicious nodes can be reported to a management potentially malicious nodes can be reported to a management
system, or can be used as a trigger for taking corrective actions. system, or can be used as a trigger for taking corrective actions.
The information can be tracked by DetNet end systems and transit The information can be tracked by DetNet end systems and transit
nodes, and exported to a management system, for example using nodes, and exported to a management system, for example using
NETCONF. YANG.
Related attacks Related attacks
Performance analytics can be used to mitigate various attacks, Performance analytics can be used to mitigate various attacks,
including the ones described in Section 3.2.1 (Delay Attack), including the ones described in Section 3.2.1 (Delay Attack),
Section 3.2.3 (Resource Segmentation Attack), and Section 3.2.8 Section 3.2.3 (Resource Segmentation Attack), and Section 3.2.8
(Time Sync Attack). (Time Sync Attack).
For example, in the case of data plane delay attacks, one possible For example, in the case of data plane delay attacks, one possible
mitigation is to timestamp the data at the source, and timestamp mitigation is to timestamp the data at the source, and timestamp
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timestamps, although they may be used by the underlying transport timestamps, although they may be used by the underlying transport
(for example TSN) to provide the service. (for example TSN) to provide the service.
5.8. Mitigation Summary 5.8. Mitigation Summary
The following table maps the attacks of Section 3 to the impacts of The following table maps the attacks of Section 3 to the impacts of
Section 4, and to the mitigations of the current section. Each row Section 4, and to the mitigations of the current section. Each row
specifies an attack, the impact of this attack if it is successfully specifies an attack, the impact of this attack if it is successfully
implemented, and possible mitigation methods. implemented, and possible mitigation methods.
Editor's note: Is this tabular summary of the above information
useful or necessary in this draft? If we opt to maintain the tables
then the WG needs to validate them for completeness and correctness
after all other draft comments have been addressed.
+----------------------+---------------------+---------------------+ +----------------------+---------------------+---------------------+
| Attack | Impact | Mitigations | | Attack | Impact | Mitigations |
+----------------------+---------------------+---------------------+ +----------------------+---------------------+---------------------+
|Delay Attack |-Non-deterministic |-Path redundancy | |Delay Attack |-Non-deterministic |-Path redundancy |
| | delay |-Performance | | | delay |-Performance |
| |-Data disruption | analytics | | |-Data disruption | analytics |
| |-Increased resource | | | |-Increased resource | |
| | consumption | | | | consumption | |
+----------------------+---------------------+---------------------+ +----------------------+---------------------+---------------------+
|Reconnaissance |-Enabler for other |-Encryption | |Reconnaissance |-Enabler for other |-Encryption |
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by industry. by industry.
6.1. Use Cases by Common Themes 6.1. Use Cases by Common Themes
In this section we review each theme and discuss the attacks that are In this section we review each theme and discuss the attacks that are
applicable to that theme, as well as anything specific about the applicable to that theme, as well as anything specific about the
impact and mitigations for that attack with respect to that theme. impact and mitigations for that attack with respect to that theme.
The table Figure 5 then provides a summary of the attacks that are The table Figure 5 then provides a summary of the attacks that are
applicable to each theme. applicable to each theme.
6.1.1. Network Layer - AVB/TSN Ethernet 6.1.1. Sub-Network Layer
DetNet is expected to run over various transmission mediums, with DetNet is expected to run over various transmission mediums, with
Ethernet being explicitly supported. Attacks such as Delay or Ethernet being the first identified. Attacks such as Delay or
Reconnaissance might be implemented differently on a different Reconnaissance might be implemented differently on a different
transmission medium, however the impact on the DetNet as a whole transmission medium, however the impact on the DetNet as a whole
would be essentially the same. We thus conclude that all attacks and would be essentially the same. We thus conclude that all attacks and
impacts that would be applicable to DetNet over Ethernet (i.e. all impacts that would be applicable to DetNet over Ethernet (i.e. all
those named in this document) would also be applicable to DetNet over those named in this document) would also be applicable to DetNet over
other transmission mediums. other transmission mediums.
With respect to mitigations, some methods are specific to the With respect to mitigations, some methods are specific to the
Ethernet medium, for example time-aware scheduling using 802.1Qbv can Ethernet medium, for example time-aware scheduling using 802.1Qbv can
protect against excessive use of bandwidth at the ingress - for other protect against excessive use of bandwidth at the ingress - for other
mediums, other mitigations would have to be implemented to provide mediums, other mitigations would have to be implemented to provide
analogous protection. analogous protection.
6.1.2. Central Administration 6.1.2. Central Administration
A DetNet network is expected to be controlled by a centralized A DetNet network can be controlled by a centralized network
network configuration and control system (CNC). Such a system may be configuration and control system. Such a system may be in a single
in a single central location, or it may be distributed across central location, or it may be distributed across multiple control
multiple control entities that function together as a unified control entities that function together as a unified control system for the
system for the network. network.
In this document we distinguish between attacks on the DetNet Control In this document we distinguish between attacks on the DetNet
plane vs. Data plane. But is an attack affecting control plane Controller plane vs. Data plane. But is an attack affecting control
packets synonymous with an attack on the CNC itself? For purposes of plane packets synonymous with an attack on the control plane itself?
this document let us consider an attack on the CNC itself to be out For purposes of this document let us consider an attack on the
of scope, and consider all attacks named in this document which are control system itself to be out of scope, and consider all attacks
relevant to control plane packets to be relevant to this theme, named in this document which are relevant to controller plane packets
including Path Manipulation, Path Choice, Control Packet Modification to be relevant to this theme, including Path Manipulation, Path
or Injection, Reconaissance and Attacks on Time Sync Mechanisms. Choice, Control Packet Modification or Injection, Reconaissance and
Attacks on Time Sync Mechanisms.
6.1.3. Hot Swap 6.1.3. Hot Swap
A DetNet network is not expected to be "plug and play" - it is A DetNet network is not expected to be "plug and play" - it is
expected that there is some centralized network configuration and expected that there is some centralized network configuration and
control system. However, the ability to "hot swap" components (e.g. control system. However, the ability to "hot swap" components (e.g.
due to malfunction) is similar enough to "plug and play" that this due to malfunction) is similar enough to "plug and play" that this
kind of behavior may be expected in DetNet networks, depending on the kind of behavior may be expected in DetNet networks, depending on the
implementation. implementation.
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Similarly if the network was designed to support runtime replacement Similarly if the network was designed to support runtime replacement
of a clock device, then presence (or apparent presence) and thus of a clock device, then presence (or apparent presence) and thus
consideration of packets from a new such device could affect the consideration of packets from a new such device could affect the
network, or the time sync of the network, for example by initiating a network, or the time sync of the network, for example by initiating a
new Best Master Clock selection process. Thus attacks on time sync new Best Master Clock selection process. Thus attacks on time sync
should be considered when designing hot swap type functionality (see should be considered when designing hot swap type functionality (see
[RFC7384]). [RFC7384]).
6.1.4. Data Flow Information Models 6.1.4. Data Flow Information Models
Data Flow Information Models specific to DetNet networks are Data Flow YANG models specific to DetNet networks are specified by
specified by DetNet, and thus are 'new' and thus potentially present DetNet, and thus are 'new' and thus potentially present a new attack
a new attack surface. surface.
6.1.5. L2 and L3 Integration 6.1.5. L2 and L3 Integration
A DetNet network integrates Layer 2 (bridged) networks (e.g. AVB/TSN A DetNet network integrates Layer 2 (bridged) networks (e.g. AVB/TSN
LAN) and Layer 3 (routed) networks via the use of well-known LAN) and Layer 3 (routed) networks via the use of well-known
protocols such as IP, MPLS-PW, and Ethernet. protocols such as IP, MPLS-PW, and Ethernet.
There are no specific entries in our table, however that does not There are no specific entries in our table, however that does not
imply that there could be no relevant attacks related to L2,L3 imply that there could be no relevant attacks related to L2,L3
integration. integration.
6.1.6. End-to-End Delivery 6.1.6. End-to-End Delivery
Packets sent over DetNet are not to be dropped by the network due to Packets sent over DetNet are not to be dropped by the network due to
congestion. (Packets may however intentionally be dropped for congestion. (Packets may however intentionally be dropped for
intended reasons, e.g. per security measures). intended reasons, e.g. per security measures).
A Data plane attack may force packets to be dropped, for example a A Data plane attack may force packets to be dropped, for example a
"long" Delay or Replication/Elimination or Flow Modification attack. "long" Delay or Replication/Elimination or Flow Modification attack.
The same result might be obtained by a Control plane attack, e.g. The same result might be obtained by a controller plane attack, e.g.
Path Manipulation or Signaling Packet Modification. Path Manipulation or Signaling Packet Modification.
It may be that such attacks are limited to Internal MITM attackers, It may be that such attacks are limited to Internal MITM attackers,
but other possibilities should be considered. but other possibilities should be considered.
An attack may also cause packets that should not be delivered to be An attack may also cause packets that should not be delivered to be
delivered, such as by forcing packets from one (e.g. replicated) path delivered, such as by forcing packets from one (e.g. replicated) path
to be preferred over another path when they should not be to be preferred over another path when they should not be
(Replication attack), or by Flow Modification, or by Path Choice or (Replication attack), or by Flow Modification, or by Path Choice or
Packet Injection. A Time Sync attack could cause a system that was Packet Injection. A Time Sync attack could cause a system that was
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6.1.7. Proprietary Deterministic Ethernet Networks 6.1.7. Proprietary Deterministic Ethernet Networks
There are many proprietary non-interoperable deterministic Ethernet- There are many proprietary non-interoperable deterministic Ethernet-
based networks currently available; DetNet is intended to provide an based networks currently available; DetNet is intended to provide an
open-standards-based alternative to such networks. In cases where a open-standards-based alternative to such networks. In cases where a
DetNet intersects with remnants of such networks or their protocols, DetNet intersects with remnants of such networks or their protocols,
such as by protocol emulation or access to such a network via a such as by protocol emulation or access to such a network via a
gateway, new attack surfaces can be opened. gateway, new attack surfaces can be opened.
For example an Inter-Segment or Control plane attack such as Path For example an Inter-Segment or Controller plane attack such as Path
Manipulation, Path Choice or Control Packet Modification/Injection Manipulation, Path Choice or Control Packet Modification/Injection
could be used to exploit commands specific to such a protocol, or could be used to exploit commands specific to such a protocol, or
that are interpreted differently by the different protocols or that are interpreted differently by the different protocols or
gateway. gateway.
6.1.8. Replacement for Proprietary Fieldbuses 6.1.8. Replacement for Proprietary Fieldbuses
There are many proprietary "field buses" used in today's industrial There are many proprietary "field buses" used in today's industrial
and other industries; DetNet is intended to provide an open- and other industries; DetNet is intended to provide an open-
standards-based alternative to such buses. In cases where a DetNet standards-based alternative to such buses. In cases where a DetNet
intersects with such fieldbuses or their protocols, such as by intersects with such fieldbuses or their protocols, such as by
protocol emulation or access via a gateway, new attack surfaces can protocol emulation or access via a gateway, new attack surfaces can
be opened. be opened.
For example an Inter-Segment or Control plane attack such as Path For example an Inter-Segment or Controller plane attack such as Path
Manipulation, Path Choice or Control Packet Modification/Injection Manipulation, Path Choice or Control Packet Modification/Injection
could be used to exploit commands specific to such a protocol, or could be used to exploit commands specific to such a protocol, or
that are interpreted differently by the different protocols or that are interpreted differently by the different protocols or
gateway. gateway.
6.1.9. Deterministic vs Best-Effort Traffic 6.1.9. Deterministic vs Best-Effort Traffic
Most of the themes described in this document address OT (reserved) Most of the themes described in this document address OT (reserved)
streams - this item is intended to address issues related to IT DetNet flows - this item is intended to address issues related to IT
traffic on a DetNet. traffic on a DetNet.
DetNet is intended to support coexistence of time-sensitive DetNet is intended to support coexistence of time-sensitive
operational (OT, deterministic) traffic and information (IT, "best operational (OT, deterministic) traffic and information (IT, "best
effort") traffic on the same ("unified") network. effort") traffic on the same ("unified") network.
With DetNet, this coexistance will become more common, and With DetNet, this coexistance will become more common, and
mitigations will need to be established. The fact that the IT mitigations will need to be established. The fact that the IT
traffic on a DetNet is limited to a corporate controlled network traffic on a DetNet is limited to a corporate controlled network
makes this a less difficult problem compared to being exposed to the makes this a less difficult problem compared to being exposed to the
open Internet, however this aspect of DetNet security should not be open Internet, however this aspect of DetNet security should not be
underestimated. underestimated.
An Inter-segment attack can flood the network with IT-type traffic An Inter-segment attack can flood the network with IT-type traffic
with the intent of disrupting handling of IT traffic, and/or the goal with the intent of disrupting handling of IT traffic, and/or the goal
of interfering with OT traffic. Presumably if the stream reservation of interfering with OT traffic. Presumably if the DetNet flow
and isolation of the DetNet is well-designed (better-designed than reservation and isolation of the DetNet is well-designed (better-
the attack) then interference with OT traffic should not result from designed than the attack) then interference with OT traffic should
an attack that floods the network with IT traffic. not result from an attack that floods the network with IT traffic.
However the DetNet's handling of IT traffic may not (by design) be as However the DetNet's handling of IT traffic may not (by design) be as
resilient to DOS attack, and thus designers must be otherwise resilient to DOS attack, and thus designers must be otherwise
prepared to mitigate DOS attacks on IT traffic in a DetNet. prepared to mitigate DOS attacks on IT traffic in a DetNet.
6.1.10. Deterministic Flows 6.1.10. Deterministic Flows
Reserved bandwidth data flows (deterministic flows) must provide the Reserved bandwidth data flows (deterministic flows) must provide the
allocated bandwidth, and must be isolated from each other. allocated bandwidth, and must be isolated from each other.
A Spoofing or Inter-segment attack which adds packet traffic to a A Spoofing or Inter-segment attack which adds packet traffic to a
bandwidth-reserved stream could cause that stream to occupy more bandwidth-reserved DetNet flow could cause that flow to occupy more
bandwidth than it is allocated, resulting in interference with other bandwidth than it was allocated, resulting in interference with other
deterministic flows. DetNet flows.
A Flow Modification or Spoofing or Header Manipulation or Control A Flow Modification or Spoofing or Header Manipulation or Control
Packet Modification attack could cause packets from one flow to be Packet Modification attack could cause packets from one flow to be
directed to another flow, thus breaching isolation between the flows. directed to another flow, thus breaching isolation between the flows.
6.1.11. Unused Reserved Bandwidth 6.1.11. Unused Reserved Bandwidth
If bandwidth reservations are made for a stream but the associated If bandwidth reservations are made for a DetNet flow but the
bandwidth is not used at any point in time, that bandwidth is made associated bandwidth is not used at any point in time, that bandwidth
available on the network for best-effort traffic. However, note that is made available on the network for best-effort traffic. However,
security considerations for best-effort traffic on a DetNet network note that security considerations for best-effort traffic on a DetNet
is out of scope of the present document, provided that such an attack network is out of scope of the present document, provided that such
does not affect performance for DetNet OT traffic. an attack does not affect performance for DetNet OT traffic.
6.1.12. Interoperability 6.1.12. Interoperability
The DetNet network specifications are intended to enable an ecosystem The DetNet network specifications are intended to enable an ecosystem
in which multiple vendors can create interoperable products, thus in which multiple vendors can create interoperable products, thus
promoting device diversity and potentially higher numbers of each promoting device diversity and potentially higher numbers of each
device manufactured. device manufactured.
Given that the DetNet specifications are unambiguously written and Given that the DetNet specifications are unambiguously written and
that the implementations are accurate, then this should not in and of that the implementations are accurate, then this should not in and of
skipping to change at page 29, line 22 skipping to change at page 29, line 32
in the implementations which have not been wrung out by extensive in the implementations which have not been wrung out by extensive
use, particularly in the case of early adopters. use, particularly in the case of early adopters.
Of the attacks we have defined, the ones identified above as relevant Of the attacks we have defined, the ones identified above as relevant
to "large" networks seem to be most relevant. to "large" networks seem to be most relevant.
6.1.17. Level of Service 6.1.17. Level of Service
A DetNet is expected to provide means to configure the network that A DetNet is expected to provide means to configure the network that
include querying network path latency, requesting bounded latency for include querying network path latency, requesting bounded latency for
a given stream, requesting worst case maximum and/or minimum latency a given DetNet flow, requesting worst case maximum and/or minimum
for a given path or stream, and so on. It is an expected case that latency for a given path or DetNet flow, and so on. It is an
the network cannot provide a given requested service level. In such expected case that the network cannot provide a given requested
cases the network control system should reply that the requested service level. In such cases the network control system should reply
service level is not available (as opposed to accepting the parameter that the requested service level is not available (as opposed to
but then not delivering the desired behavior). accepting the parameter but then not delivering the desired
behavior).
Control plane attacks such as Signaling Packet Modification and Controller plane attacks such as Signaling Packet Modification and
Injection could be used to modify or create control traffic that Injection could be used to modify or create control traffic that
could interfere with the process of a user requesting a level of could interfere with the process of a user requesting a level of
service and/or the network's reply. service and/or the network's reply.
Reconnaissance could be used to characterize flows and perhaps target Reconnaissance could be used to characterize flows and perhaps target
specific flows for attack via the Control plane as noted above. specific flows for attack via the controller plane as noted above.
6.1.18. Bounded Latency 6.1.18. Bounded Latency
DetNet provides the expectation of guaranteed bounded latency. DetNet provides the expectation of guaranteed bounded latency.
Delay attacks can cause packets to miss their agreed-upon latency Delay attacks can cause packets to miss their agreed-upon latency
boundaries. boundaries.
Time Sync attacks can corrupt the system's time reference, resulting Time Sync attacks can corrupt the system's time reference, resulting
in missed latency deadlines (with respect to the "correct" time in missed latency deadlines (with respect to the "correct" time
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Applications may require "extremely low latency" however depending on Applications may require "extremely low latency" however depending on
the application these may mean very different latency values; for the application these may mean very different latency values; for
example "low latency" across a Utility grid network is on a different example "low latency" across a Utility grid network is on a different
time scale than "low latency" in a motor control loop in a small time scale than "low latency" in a motor control loop in a small
machine. The intent is that the mechanisms for specifying desired machine. The intent is that the mechanisms for specifying desired
latency include wide ranges, and that architecturally there is latency include wide ranges, and that architecturally there is
nothing to prevent arbitrarily low latencies from being implemented nothing to prevent arbitrarily low latencies from being implemented
in a given network. in a given network.
Attacks on the Control plane (as described in the Level of Service Attacks on the controller plane (as described in the Level of Service
theme) and Delay and Time attacks (as described in the Bounded theme) and Delay and Time attacks (as described in the Bounded
Latency theme) both apply here. Latency theme) both apply here.
6.1.20. Bounded Jitter (Latency Variation) 6.1.20. Bounded Jitter (Latency Variation)
DetNet is expected to provide bounded jitter (packet to packet DetNet is expected to provide bounded jitter (packet to packet
latency variation). latency variation).
Delay attacks can cause packets to vary in their arrival times, Delay attacks can cause packets to vary in their arrival times,
resulting in packet to packet latency variation, thereby violating resulting in packet to packet latency variation, thereby violating
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6.1.23. Redundant Paths 6.1.23. Redundant Paths
DetNet based systems are expected to be implemented with essentially DetNet based systems are expected to be implemented with essentially
arbitrarily high reliability/availability. A strategy used by DetNet arbitrarily high reliability/availability. A strategy used by DetNet
for providing such extraordinarily high levels of reliability is to for providing such extraordinarily high levels of reliability is to
provide redundant paths that can be seamlessly switched between, all provide redundant paths that can be seamlessly switched between, all
the while maintaining the required performance of that system. the while maintaining the required performance of that system.
Replication-related attacks are by definition applicable here. Replication-related attacks are by definition applicable here.
Control plane attacks can also interfere with the configuration of Controller plane attacks can also interfere with the configuration of
redundant paths. redundant paths.
6.1.24. Security Measures 6.1.24. Security Measures
A DetNet network must be made secure against devices failures, A DetNet network must be made secure against devices failures,
attackers, misbehaving devices, and so on. Does the threat affect attackers, misbehaving devices, and so on. Does the threat affect
such security measures themselves, e.g. by attacking SW designed to such security measures themselves, e.g. by attacking SW designed to
protect against device failure? protect against device failure?
This is TBD, thus there are no specific entries in our table, however This is TBD, thus there are no specific entries in our table, however
that does not imply that there could be no relevant attacks. that does not imply that there could be no relevant attacks.
6.2. Attack Types by Use Case Common Theme 6.2. Attack Types by Use Case Common Theme
The following table lists the attacks of Section 3, assigning a The following table lists the attacks of Section 3, assigning a
number to each type of attack. That number is then used as a short number to each type of attack. That number is then used as a short
form identifier for the attack in Figure 5. form identifier for the attack in Figure 5.
Editor's note: Is this tabular summary of the above information
useful or necessary in this draft? If we opt to maintain the tables
then the WG needs to validate them for completeness and correctness
after all other draft comments have been addressed.
+--+----------------------------------------+----------------------+ +--+----------------------------------------+----------------------+
| | Attack | Section | | | Attack | Section |
+--+----------------------------------------+----------------------+ +--+----------------------------------------+----------------------+
| 1|Delay Attack | Section 3.2.1 | | 1|Delay Attack | Section 3.2.1 |
+--+----------------------------------------+----------------------+ +--+----------------------------------------+----------------------+
| 2|DetNet Flow Modification or Spoofing | Section 3.2.2 | | 2|DetNet Flow Modification or Spoofing | Section 3.2.2 |
+--+----------------------------------------+----------------------+ +--+----------------------------------------+----------------------+
| 3|Inter-Segment Attack | Section 3.2.3 | | 3|Inter-Segment Attack | Section 3.2.3 |
+--+----------------------------------------+----------------------+ +--+----------------------------------------+----------------------+
| 4|Replication: Increased attack surface | Section 3.2.4.1 | | 4|Replication: Increased attack surface | Section 3.2.4.1 |
skipping to change at page 36, line 45 skipping to change at page 36, line 45
Having attended to the conventional aspects of network security it is Having attended to the conventional aspects of network security it is
necessary to attend to the dynamic aspects. The closest experience necessary to attend to the dynamic aspects. The closest experience
that the IETF has with securing protocols that are sensitive to that the IETF has with securing protocols that are sensitive to
manipulation of delay are the two way time transfer protocols (TWTT), manipulation of delay are the two way time transfer protocols (TWTT),
which are NTP [RFC5905] and Precision Time Protocol [IEEE1588]. The which are NTP [RFC5905] and Precision Time Protocol [IEEE1588]. The
security requirements for these are described in [RFC7384]. security requirements for these are described in [RFC7384].
One particular problem that has been observed in operational tests of One particular problem that has been observed in operational tests of
TWTT protocols is the ability for two closely but not completely TWTT protocols is the ability for two closely but not completely
synchronized streams to beat and cause a sudden phase hit to one of synchronized flows to beat and cause a sudden phase hit to one of the
the streams. This can be mitigated by the careful use of a flows. This can be mitigated by the careful use of a scheduling
scheduling system in the underlying packet transport. system in the underlying packet transport.
Further consideration of protection against dynamic attacks is work Further consideration of protection against dynamic attacks is work
in progress. in progress.
8. IANA Considerations 8. IANA Considerations
This memo includes no requests from IANA. This memo includes no requests from IANA.
9. Security Considerations 9. Security Considerations
The security considerations of DetNet networks are presented The security considerations of DetNet networks are presented
throughout this document. throughout this document.
10. Informative References 10. Contributors
The Editor would like to recognize the contributions of the following
individuals to this draft.
Andrew J. Hacker (MistIQ Technologies, Inc)
Harrisburg, PA, USA
email ajhacker@mistiqtech.com,
web http://www.mistiqtech.com
Subir Das (Applied Communication Sciences)
150 Mount Airy Road, Basking Ridge
New Jersey, 07920, USA
email sdas@appcomsci.com
John Dowdell (Airbus Defence and Space)
Celtic Springs, Newport, NP10 8FZ, United Kingdom
email john.dowdell.ietf@gmail.com
Henrik Austad (SINTEF Digital)
Klaebuveien 153, Trondheim, 7037, Norway
email henrik@austad.us
Norman Finn
email nfinn@nfinnconsulting.com
Carsten Bormann
11. Informative References
[ARINC664P7] [ARINC664P7]
ARINC, "ARINC 664 Aircraft Data Network, Part 7, Avionics ARINC, "ARINC 664 Aircraft Data Network, Part 7, Avionics
Full-Duplex Switched Ethernet Network", 2009. Full-Duplex Switched Ethernet Network", 2009.
[I-D.ietf-detnet-data-plane-framework] [I-D.ietf-detnet-data-plane-framework]
Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., Varga, B., Farkas, J., Berger, L., Malis, A., and S.
Bryant, S., and J. Korhonen, "DetNet Data Plane Bryant, "DetNet Data Plane Framework", draft-ietf-detnet-
Framework", draft-ietf-detnet-data-plane-framework-03 data-plane-framework-04 (work in progress), February 2020.
(work in progress), October 2019.
[I-D.ietf-detnet-flow-information-model]
Farkas, J., Varga, B., Cummings, R., Jiang, Y., and D.
Fedyk, "DetNet Flow Information Model", draft-ietf-detnet-
flow-information-model-07 (work in progress), March 2020.
[I-D.ietf-detnet-ip] [I-D.ietf-detnet-ip]
Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A.,
Bryant, S., and J. Korhonen, "DetNet Data Plane: IP", and S. Bryant, "DetNet Data Plane: IP", draft-ietf-detnet-
draft-ietf-detnet-ip-04 (work in progress), November 2019. ip-05 (work in progress), February 2020.
[I-D.ietf-detnet-ip-over-tsn] [I-D.ietf-detnet-ip-over-tsn]
Varga, B., Farkas, J., Malis, A., and S. Bryant, "DetNet Varga, B., Farkas, J., Malis, A., and S. Bryant, "DetNet
Data Plane: IP over IEEE 802.1 Time Sensitive Networking Data Plane: IP over IEEE 802.1 Time Sensitive Networking
(TSN)", draft-ietf-detnet-ip-over-tsn-01 (work in (TSN)", draft-ietf-detnet-ip-over-tsn-02 (work in
progress), October 2019. progress), March 2020.
[I-D.ietf-detnet-mpls] [I-D.ietf-detnet-mpls]
Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A., Varga, B., Farkas, J., Berger, L., Fedyk, D., Malis, A.,
Bryant, S., and J. Korhonen, "DetNet Data Plane: MPLS", Bryant, S., and J. Korhonen, "DetNet Data Plane: MPLS",
draft-ietf-detnet-mpls-04 (work in progress), November draft-ietf-detnet-mpls-05 (work in progress), February
2019. 2020.
[I-D.varga-detnet-service-model] [I-D.varga-detnet-service-model]
Varga, B. and J. Farkas, "DetNet Service Model", draft- Varga, B. and J. Farkas, "DetNet Service Model", draft-
varga-detnet-service-model-02 (work in progress), May varga-detnet-service-model-02 (work in progress), May
2017. 2017.
[IEEE1588] [IEEE1588]
IEEE, "IEEE 1588 Standard for a Precision Clock IEEE, "IEEE 1588 Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and Synchronization Protocol for Networked Measurement and
Control Systems Version 2", 2008. Control Systems Version 2", 2008.
skipping to change at page 38, line 20 skipping to change at page 39, line 9
[IEEE802.1Qch-2017] [IEEE802.1Qch-2017]
IEEE Standards Association, "IEEE Standard for Local and IEEE Standards Association, "IEEE Standard for Local and
metropolitan area networks--Bridges and Bridged Networks-- metropolitan area networks--Bridges and Bridged Networks--
Amendment 29: Cyclic Queuing and Forwarding", 2017, Amendment 29: Cyclic Queuing and Forwarding", 2017,
<https://ieeexplore.ieee.org/document/7961303>. <https://ieeexplore.ieee.org/document/7961303>.
[MIRAI] krebsonsecurity.com, "https://krebsonsecurity.com/2016/10/ [MIRAI] krebsonsecurity.com, "https://krebsonsecurity.com/2016/10/
hacked-cameras-dvrs-powered-todays-massive-internet- hacked-cameras-dvrs-powered-todays-massive-internet-
outage/", 2016. outage/", 2016.
[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, DOI 10.17487/RFC2475, December 1998,
<https://www.rfc-editor.org/info/rfc2475>.
[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC [RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC
Text on Security Considerations", BCP 72, RFC 3552, Text on Security Considerations", BCP 72, RFC 3552,
DOI 10.17487/RFC3552, July 2003, DOI 10.17487/RFC3552, July 2003,
<https://www.rfc-editor.org/info/rfc3552>. <https://www.rfc-editor.org/info/rfc3552>.
[RFC3931] Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed., [RFC3931] Lau, J., Ed., Townsley, M., Ed., and I. Goyret, Ed.,
"Layer Two Tunneling Protocol - Version 3 (L2TPv3)", "Layer Two Tunneling Protocol - Version 3 (L2TPv3)",
RFC 3931, DOI 10.17487/RFC3931, March 2005, RFC 3931, DOI 10.17487/RFC3931, March 2005,
<https://www.rfc-editor.org/info/rfc3931>. <https://www.rfc-editor.org/info/rfc3931>.
skipping to change at page 40, line 4 skipping to change at page 40, line 34
"Deterministic Networking Architecture", RFC 8655, "Deterministic Networking Architecture", RFC 8655,
DOI 10.17487/RFC8655, October 2019, DOI 10.17487/RFC8655, October 2019,
<https://www.rfc-editor.org/info/rfc8655>. <https://www.rfc-editor.org/info/rfc8655>.
Authors' Addresses Authors' Addresses
Tal Mizrahi Tal Mizrahi
Huawei Network.IO Innovation Lab Huawei Network.IO Innovation Lab
Email: tal.mizrahi.phd@gmail.com Email: tal.mizrahi.phd@gmail.com
Ethan Grossman (editor) Ethan Grossman (editor)
Dolby Laboratories, Inc. Dolby Laboratories, Inc.
1275 Market Street 1275 Market Street
San Francisco, CA 94103 San Francisco, CA 94103
USA USA
Phone: +1 415 645 4726 Phone: +1 415 645 4726
Email: ethan.grossman@dolby.com Email: ethan.grossman@dolby.com
URI: http://www.dolby.com URI: http://www.dolby.com
Andrew J. Hacker
MistIQ Technologies, Inc
Harrisburg, PA
USA
Phone:
Email: ajhacker@mistiqtech.com
URI: http://www.mistiqtech.com
Subir Das
Applied Communication Sciences
150 Mount Airy Road, Basking Ridge
New Jersey, 07920
USA
Email: sdas@appcomsci.com
John Dowdell
Airbus Defence and Space
Celtic Springs
Newport NP10 8FZ
United Kingdom
Email: john.dowdell.ietf@gmail.com
Henrik Austad
SINTEF Digital
Klaebuveien 153
Trondheim 7037
Norway
Email: henrik@austad.us
Norman Finn
Huawei
Email: norman.finn@mail01.huawei.com
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