DetNet Data Plane: IEEE 802.1 Time Sensitive Networking over SRv6
draft-wang-detnet-tsn-over-srv6-06
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Xueshun Wang , Jinyou Dai , Jianhua Liu , Feng Zhang | ||
| Last updated | 2022-12-18 | ||
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| Intended RFC status | (None) | ||
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| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
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draft-wang-detnet-tsn-over-srv6-06
DetNet
Internet-Draft X. Wang
Intended status: Standards Track J. Dai
Expires: June 18, 2023 J. Liu
F.Zhang
Fiberhome Telecom LTD
December 18, 2022
DetNet Data Plane: IEEE 802.1 Time Sensitive Networking over SRv6
draft-wang-detnet-tsn-over-srv6-06
Abstract
This document specifies the Deterministic Networking data plane when
TSN networks interconnected over an Segment Routing IPv6 Packet
Switched Networks.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Task Force (IETF). Note that other groups may also distribute
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 18, 2023.
Copyright Notice
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Terms Used in This Document . . . . . . . . . . . . . . . 3
2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3
3. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
4. IEEE 802.1 TSN Over SRv6 Data Plane Scenario . . . . . . . . . 4
5. IEEE 802.1 TSN Operation Over SRv6 Sub-Networks. . . . . . . 5
5.1. Mapping of TSN Stream ID and Sequence Number . . . . . . . 5
5.2. SRv6 Network Programming new Functions . . . . . . . . . . 8
5.2.1. End. B.Replication DetNet SID: Packet Replication
Function . . . . . . . . . . . . . . . . . . . . . . 8
5.2.2. End. B. Elimination: Packet Elimination Function. . . . 9
6. SRv6 Data Plane Considerations . . . . . . . . . . . . . . . . 9
6.1. DetNet PREOF . . . . . . . . . . . . . . . . . . . . . . 9
6.2. Edge Node Processing . . . . . . . . . . . . . . . . . . 10
6.3. MTU and Fragmentation . . . . . . . . . . . . . . . . . . 10
7. Management and Control Information Summary. . . . . . . . . . . 11
8. Security Considerations . . . . . . . . . . . . . . . . . . . 12
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
11. Normative References. . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
Deterministic Networking (DetNet) is a service that can be offered as
DetNet flows in network. DetNet provides these flows extremely low
packet loss rates and assured bounded end-to-end delivery latency.
General background and concepts of DetNet can be found in the DetNet
Architecture [RFC8655].
Segment Routing(SR) leverages the source routing paradigm. An ingress
node steers a packet through an ordered list of instructions, called
"segments". SR can be applied over IPv6 data plane using Routing
Extension Header [RFC8754]. A segment in Segment Routing is not
limited to a routing/forwarding function. A SRv6 Segment can
indicate functions that are executed locally in the node where they
are defined. [RDC8986] describes some well-known functions and
segments associated to them. SRH TLVs ([RFC8754]) also provides
meta-data for segment processing. All these features make SRv6
suitable to carry DetNet flows by defining new segments associated
with DetNet functions and Meta data for DetNet.
The Time-Sensitive Networking (TSN) is to provide deterministic
services through IEEE 802 networks, i.e., guaranteed packet transport
with bounded latency, low packet delay variation,and low packet loss.
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The TSN is a unified industrial Ethernet standard, and supports
production control and information application.
TSN over DetNet needs to focus on the real-time interconnection of
multi-subnet network layer. Based on the existing mechanism of TSN,
interface scheduling is carried out for routers, firewalls, servers
and other devices, in order to ensure the deterministic network
services between cross-domain subnets. The remote control
requirements across networks of TSN need deterministic transmission
of network services through DetNet technology. TSN needs to be
deployed with DetNet technology in larger areas such as networking
of plant equipment, automatic building control of plant and office
buildings.
This document defines how to carry DetNet IEEE 802.1 TSN flows over
SRv6 networks.
2. Terminology
2.1. Terms Used in This Document
This document uses the terminology and concepts established in the
DetNet architecture [RFC8655] and [RFC8938]. The reader is assumed
to be familiar with these documents and their terminology.
2.2. Abbreviations
Terminologies for DetNet go along with the definition in [RFC8655].
The following abbreviations are used in this document:
CE: Customer Edge equipment.
CoS: Class of Service.
DetNet: Deterministic Networking.
DF: DetNet Flow.
L2: Layer 2.
L3: Layer 3.
OAM: Operations, Administration, and Maintenance.
PE: Provider Edge.
PEF: Packet Elimination Function.
PRF: Packet Replication Function.
PREOF: Packet Replication, Elimination and Ordering Functions.
POF: Packet Ordering Function.
QoS: Quality of Service.
TSN: IEEE 802.1 Time-Sensitive Network.
SR: Segment Routing.
SRv6: Segment Routing IPv6.
SL: Segment Left.
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NH: The IPv6 next-header field.
SID: A Segment Identifier ([RFC8402]).
SRH: The Segment Routing Header ([RFC8754]).
3. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
4. IEEE 802.1 TSN over SRv6 Data Plane Scenario
Realize the DetNet network in the Internet and connect with the time
sensitive network in the factory. Figure 1 illustrates how DetNet can
provide services for IEEE 802.1 TSN end systems, CE1 and CE2, over a
DetNet enabled SRv6 network. DetNet Edge Nodes sit at the boundary of
a DetNet domain. They are responsible for mapping non-DetNet aware L2
traffic to DetNet services. They also support the imposition and
disposition of the required DetNet encapsulation. They understand and
support IEEE 802.1 TSN and are able to map TSN flows into DetNet
flows. Edge nodes, PE1 and PE2, insert and remove required DetNet
SRv6 data plane encapsulation. The 'X' in the edge nodes and relay
node, R1, represent a potential DetNet compound flow packet
replication and elimination point.
TSN |<------- End to End DetNet Service ------>| TSN
Service | Sub Sub | Service
TSN (AC) | |network| |network| | (AC) TSN
Talker/ | V V V V V V | Talker/
Listener| +--------+ +--------+ +--------+ |Listener
+---+ | | PE1 | | R1 | | PE2 | | +---+
| |---|----| X |------ | X |------ | X |---|--| |
|CE1| | | | | | | | | |CE2|
+---+ +--------+ +--------+ +--------+ +---+
| Edge Node Relay Node Edge Node |
| |
|<- TSN -> <------- TSN Over DetNet SRv6 -------> <- TSN ->|
| |
|<--- Emulated Time Sensitive Networking (TSN) Service --->|
X = Service protection
Figure 1: IEEE 802.1TSN Over DetNet SRv6
Native TSN flow and DetNet SRv6 flow differ not only by the
additional SRH specific encapsulation, but DetNet SRv6 flows have on
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each DetNet node an associated DetNet specific data structure, what
defines flow related characteristics and required forwarding
functions. In this example, edge Nodes provide a service proxy
function that "associates" the DetNet flows and native flows at the
edge of the DetNet domain. This ensures that the DetNet SRv6 Flow is
properly served at the Edge node (and inside the domain).
5. IEEE 802.1 TSN Operation Over SRv6 Sub-Networks
A classical SRv6 data plane solution is showed in the picture below:
+-------------------+ -
| DATA | \
+-------------------+ -IPv6 payload
|TSN Ethernet Header| /
+-------------------+ +-------------------+ -
| DATA | | SRH |
+-------------------+ +-------------------+
|TSN Ethernet Header| ----> | IPv6 Header |
+-------------------+ +-------------------+
Figure 2: SRv6 DetNet data plane solution
In SRv6 for DetNet, the DATA with the SRH is used for
carrying DetNet flows. Traffic Engineering is instantiated in the
segment list of SRH, and other functions and arguments for service
protection (packet replication, elimination and ordering) and
congestion control (packet queuing and forwarding) are also defined
in the SRH.
The Time-Sensitive Networking (TSN) Task Group of the IEEE 802.1
Working Group have defined (and are defining) a number of amendments
to IEEE 802.1Q [IEEE8021Q] that provides zero congestion loss and
bounded latency in bridged networks. Furthermore IEEE 802.1CB
[IEEE8021CB] defines frame replication and elimination functions for
reliability that should prove both compatible with and useful to
DetNet networks. All these functions have to identify flows those
require TSN treatment.
The challenge for SRv6 flows is that the protocol interworking
function defined in IEEE 802.1CB [IEEE8021CB] does not works for
segment list of SRH flows. The aim of the protocol interworking
function is to convert a TSN ingress flow (for examples, identified
by a specific destination MAC address and VLAN) to segment list of
SRH. A similar interworking pair at the other end of the SRv6 sub-
network would restore the packet to its original TSN packet.
The TSN layer 2 header and application payload carried by the TSN
network are encapsulated in IPv6 payload field as figure 2.
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5.1. IPv6 Header
The Edge Node encapsulates the Ipv6 Heade when a TSN packet go into
DetNet SRv6 network, the Ipv6 header field values are as follows:
Version: 6, represented as Ipv6 packets;
Traffic Class: the level of the DetNet stream from Control Plane, if
not, the same as the vlan priority in the TSN packet;
Flow label: as default incremental value by the edge node or same as
the Sequence Number in the TSN packet;
Payload Length: according to the Ipv6 packet length, it is equal to
the TSN packet length normally;
Next Header: 43, represents the Ipv6 routing extension head;
Hop Limit: set as default value;
Source Address: the sender Ipv6 address. when the packets from CE1
to CE2 as shown in figure 1, the PE1 node encapsulate Ipv6 Header
source address as its own Ipv6 address;
Destination Address: the receiver Ipv6 address. when the packets
from CE1 to CE2 as shown in figure 1, the PE1 node encapsulate
Ipv6 Header destination address as the PE2 Ipv6 address.
5.2. DetNet SID Mapping from TSN Stream
The Srv6 network edge node uses BGP protocol to announce SRv6 service
Sid. SRv6 edge node encapsulates the data payload in the outer IPv6
header and sets the outer destination address as the service Sid. The
underlying network between the edge nodes needs to support IPv6
according to [RFC8200], and can transform TSN data flow into srv6
service.
The Edge node MUST provide the SRv6 sub-network specific
segment list of SRH encapsulation over the link(s) towards the sub-
network. A SRv6-aware edge node MUST support the following TSN
components:
1. For recognizing flows:
* Stream Identification (SRv6-flow-aware).
2. For FRER used inside the TSN domain, additionally:
* Sequencing function (SRv6-flow-aware);
* Sequence encode/decode function.
3. For FRER when the node is a TSN replication or elimination point.
additionally:
* Stream splitting function;
* Individual recovery function.
The Time-Sensitive Networking (TSN) Task Group of the IEEE 802.1
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Working Group has defined Stream identification in section 6.1 of
IEEE 802.1CB [IEEE8021CB]. Four specific Stream identification
functions are described: Null Stream identification, Source MAC and
VLAN Stream identification, Active Destination MAC and VLAN Stream
identification, and IP Stream identification. These Stream
identification functions are summarized as follow:
o Null Stream identification: destination MAC address, vlan
identifier.
o Source MAC and VLAN Stream identification: source MAC address, vlan
identifier.
o Active Destination MAC and VLAN Stream identification: destination
MAC address, vlan identifier.
o IP Stream identification: destination MAC address, vlan identifier,
IP source address, IP destination address, DSCP, IP next protocol,
source port, destination port.
The SRH for DetNet in the IPv6 header is showed as follows, according
to [RFC8754], [draft-geng-detnet-dp-sol-srv6-02] and [RFC8986]:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Header | Hdr Ext Len | Routing Type | Segment Left |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Last Entry | Flags | Tag |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| DetNet SID |
| Segment List(0) (128-bit) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Segment List(n) (128-bit IPv6 address) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Optional Type Length Value objects (variable) //
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: SRH for DetNet
The DetNet SRv6 flow is identified by DetNet SID in SRH. DetNet SID
is defined as a 128-bit value.
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A new DetNet SID is defined to support DetNet service protection for
TSN stream. It is used to uniquely identify a DetNet flow in a SRv6
DetNet node and to discriminate packets in the same DetNet flow by
sequence number. DetNet SID is defined as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Flow Identification |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow Identification |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow Identification | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Frag | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: DetNet SID for Flow Identification
Where:
o Type: 8bits, to be assigned by IANA.
o Length: 8 bits.
o Flow Identification: 64 bits, which is used for identifying DetNet
flow.
o RESERVED: 20 bits, MUST be 0 on transmission and ignored on
receipt.
o Sequence Number: 28 bits, which is used for indicating sequence
number of a DetNet flow.
o Frag: 4 bits, if a packet must be divided into multiple packages
for transmission, record the fragmentation number.
When TSN stream is transmitted over a SRv6 network, TSN Stream
Identification MUST pair SRv6 flows and TSN Streams and encode that
in data plane formats as well. When the new DetNet SID is used to
identify DetNet flow and the mapping for TSN stream is as follows:
o Type: 8bits, to be assigned by IANA, used to identify sources from
the TSN stream.
o Length: 8 bits, the value is 16 octets.
o Flow Identification: 64 bits, which is used for identifying DetNet
flow. The former 48 bit corresponds to the MAC address identified
by the TSN stream, and the post 16 bit comes from the VLAN-ID and
priority parameters in TSN packet.
o RESERVED: 20 bits, MUST be 0 on transmission and ignored on
receipt.
o Sequence Number: 28 bits, which is used for indicating sequence
number of a DetNet flow. The value comes from the Redundancy tag
(R-TAG) in TSN packet as defined in Clause 7.8 of IEEE 802.1CB
[IEEE8021CB].
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Flow Identification in SRH can identify Null Stream, Source MAC and
VLAN Stream, Active Destination MAC and VLAN Stream in TSN stream.
For TSN IP Stream, destination MAC address and vlan is still
indicated by flow Identification, other IP-based fields correspond
to IP fields in SRv6 one by one, such as IP source address, IP
destination address, DSCP, IP next protocol, source port, destination
port etc.
5.3. SRv6 Network Programming new Functions
New SRv6 Network Programming functions are defined as follows:
5.3.1. End. B.Replication DetNet SID: Packet Replication Function
When N receives a packet whose IPv6 DA is S and S is a local End.B.
SL is Segment Left(SL), Replication DetNet SID, does:
S01. IF NH=SRH & SL>0 THEN {
S02. Extract the DetNet SID values from the SRH or TSN Stream
identification and TSN Rtag.
S03. Create two new outer IPv6+SRH headers: IPv6-SRH-1 and
IPv6-SRH-2 Insert the policy-instructed segment lists in each
newly created SRH (SRH-1 and SRH-2). Also, add the extracted
DetNet SID into SRH-1 and SRH-2.
S04. Remove the incoming outer IPv6+SRH header, restore DATA as the
original packet.
S05. Create a duplication of the restore DATA as the duplicate
packet.
S06. Encapsulate the original packet into the first outer IPv6+SRH
header: (IPv6-SRH-1) (original packet)
S07. Encapsulate the duplicate packet into the second outer IPv6+SRH
header: (IPv6-SRH-2) (duplicate packet)
S08. Set the IPv6 SA as the local address of this node.
S09. Set the IPv6 DA of IPv6-SRH-1 to the first segment of the SRv6
Policy in of SRH-1 segment list.
S10. Set the IPv6 DA of IPv6-SRH-2 to the first segment of the SRv6
Policy in of SRH-2 segment list.
S11. }
5.3.2. End. B. Elimination: Packet Elimination Function
When N receives a packet whose IPv6 DA is S and S is a local End.B.
SL is Segment Left(SL), Elimination DetNet SID, does:
S01. IF NH=SRH & SL>0 & "the packet is not a redundant packet" THEN {
S02. Do not decrement SL nor update the IPv6 DA with SRH(SL)
S03. Extract the value of DetNet SID from the SRH
S04. Extract Flow Identification and Sequence Number from DetNet
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SID.
S05. IF NOT receive the packet with the same Flow Identification
and Sequence Number {
S06. Create a new outer IPv6+SRH header
S07. Insert the policy-instructed segment lists in the newly
created SRH and add the retrieved DetNet SID in the newly
created SRH
S08. Remove the incoming outer IPv6+SRH header.
S09. Set the IPv6 DA to the first segment of the SRv6 Policy in
the newly created SRH
S10. } Else {
S11. Drop the packet
S12. }
S13. }
6. SRv6 Data Plane Considerations
6.1. DetNet PREOF
Flow Identification and sequence number are necessary in the
encapsulation of SRv6 for DetNet in order to support service
protection. Replication nodes decide which DetNet flows are supposed
to be replicated by the flow identification. Elimination nodes
decide whether a packet should be dropped because of redundancy by
the flow identification and sequence number.
FRER function and the provided service recovery is available in that
the Stream-ID and the TSN sequence number are paired with the SRv6
flow parameters they can be combined with PREOF functions.
SRv6 supporting DetNet flows may use Packet Replication, Elimination
and Ordering Functions (PREOF) based on the DetNet SID in SRH, which
is derived from TSN Stream. The specific operation of Frame
Replication and Elimination for Redundancy (FRER) [802.1CB] is not
modified by the use of DetNet and follows IEEE 802.1CB [IEEE8021CB].
6.2. Edge Node Processing
An edge node is responsible for matching ingress packets to the
service they require and encapsulating them accordingly. An edge node
is a SRv6 DetNet-aware forwarder, and may participate in the packet
replication and duplication elimination.
The Controller sends Detnet SRv6 polices to the edge node. These
polices include mapping of ingress TSN stream to DetNet SRv6 flow.
The detnet SID is associated with an SR Policy, and its value comes
from a TSN packet. When the edge node forwards a TSN packet to SRv6
network, inserting an SRH with the policy and adds an outer IPv6
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header. The TSN flow identification and sequence number is copied to
DetNet SID in SRv6 SRH.
Additionally the DetNet-aware edge node does duplicate frame
elimination based on the flow identification and the sequence number
combination. The packet replication is also done within the
DetNet-aware forwarder. During elimination and the replication
process the sequence number of the DetNet member flow MUST be
preserved and copied to the egress DetNet member flow.
6.3. MTU and Fragmentation
Because the SRH field is added during transmission in the srv6
network, the data packet may exceed the MTU of the device interface,
so it is necessary to divide the packet. The serial number of the
fragment packet is recorded in the frag field of DetNet Sid for flow
identification. At the SRv6 network edge node, reorganize these
received fragment packets as one packet and send it to the TSN
network.
In the process of fragment, the Flow Identification number and
Sequence Number of the packet are consistent with the original
packet. Based on the Flow Identification number of each stream, the
transmission node sends the fragment alarm information to the
controller.
7. Management and Control Information Summary
The following summarizes the set of information that is needed to
support TSN over SRv6 at the ingress edge node:
o TSN Stream identification and TSN R-tag information to be mapped to
SRv6 SRH SID. Note that a single TSN Stream identification can map
to one SRH DetNet SID, and it can used for PREOF.
o IPv6 source address.
o IPv6 destination address.
o IPv6 Traffic Class.
This information MUST be provisioned per DetNet flow via
configuration, e.g., via the controller or management plane.
It is the responsibility of the DetNet controller plane to properly
provision both flow identification information and the flow specific
resources needed to be provided the traffic treatment needed to meet
each flow's service requirements. This applies for aggregated and
individual flows.
DetNet SRv6 flow and TSN Stream mapping related information are
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required only for DetNet SRv6 edge nodes; the edge node is TSN-aware
and DetNet SRv6-aware node. These DetNet SRv6 edge nodes are member
of both the DetNet SRv6 domain and the TSN sub-network. Within the
TSN sub-network the DetNet SRv6 node may has a TSM-aware role, so TSN
specific management and control plane functionalities must be
implemented. There are many similarities in the management plane
techniques used in DetNet and TSN, but that is not the case for the
control plane protocols. For example, RSVP-TE and MSRP behaves
differently. Therefore management and control plane design is an
important aspect of scenarios, where mapping between DetNet SRv6 and
TSN is required.
In order to use a DetNet SRv6 sub-network between TSN nodes, TSN
stream specific information must be converted to SRv6 DetNet SRH. TSN
Stream ID and stream related parameters/requirements must be
converted to a SRv6 DetNet flow ID and flow related parameters/
requirements. Note that, as the DetNet SRv6 sub-network is just a
portion of the end2end TSN path (i.e., single hop from IP
perspective), some parameters (e.g., delay) may differ significantly.
Other TSN stream parameters (like bandwidth) also may have to be
tuned due to the SRv6 encapsulation used in the DetNet sub-network.
In some case it may be challenging to determine some TSN Stream
related information. For example which DetNet SRv6 paths are
multi-Listener of the mapped TSN stream to one TSN stream Talker?
However it may be not trivial to locate the point/interface where
that Listener is connected to the TSN sub-network. Such
attributes may require interaction between control and management
plane functions and between DetNet SRv6 and TSN domains.
Mapping between DetNet SRv6 flow identifiers and TSN Stream
identifiers, if not provided explicitly, can be done by a DetNet SRv6
node locally based on the configuration of SRv6 Behaviors associated
with a SID.
8. Security Considerations
This document will not introduce new security problems.
9. IANA Considerations
This document requests assigning new DetNet SID TLV code-points as
described in section 5.
10. Acknowledgements
Thanks for Guanghua Lan and Ximing Dong for their comments and
contributions.
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11. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", RFC 8174, May 2017,
<https://www.rfc-editor.org/info/rfc8174>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>.
[RFC8655] Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", RFC 8655, May
2019, <https://www.rfc-editor.org/info/rfc8655>.
[RFC8754] Filsfils, C., Dukes, D., Previdi, S., Leddy, J.,
Matsushima, S., and d. daniel.voyer@bell.ca, "IPv6 Segment
Routing Header (SRH)", RFC 8754, June 2019.
<https://www.rfc-editor.org/info/rfc8754>.
[IEEE8021CB]
Finn, N., "Draft Standard for Local and metropolitan area
networks - Seamless Redundancy", IEEE P802.1CB
/D2.1 P802.1CB, December 2015,
<http://www.ieee802.org/1/files/private/cb-drafts/
d2/802-1CB-d2-1.pdf>.
[IEEE8021Q]
IEEE 802.1, "Standard for Local and metropolitan area
networks--Bridges and Bridged Networks (IEEE Std 802.1Q-
2014)", 2014, <http://standards.ieee.org/about/get/>.
[RFC8986]
Filsfils, C., Camarillo, P., Leddy, J.,
daniel.voyer@bell.ca, d., Matsushima, S., and Z. Li, "SRv6
Network Programming", RFC8986, February 2021.
<https://www.rfc-editor.org/info/rfc8986>.
Authors' Addresses
Xueshun Wang
Fiberhome Telecom LTD
Email: xswang@fiberhome.com
Jinyou Dai
Fiberhome Telecom LTD
Email: djy@fiberhome.com
Jianhua Liu
Wang, et al. Expires June 18, 2023 [Page 13]
Internet-Draft DetNet TSN over SRv6 December 18, 2022
Fiberhome Telecom LTD
Email: liujianhua@fiberhome.com
Feng Zhang
Fiberhome Telecom LTD
Email: fengzhang@fiberhome.com
Wang, et al. Expires June 18, 2023 [Page 14]