DetNet Data Plane: IP over IEEE 802.1 Time Sensitive Networking (TSN)
draft-ietf-detnet-ip-over-tsn-00
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| Authors | Balazs Varga , János Farkas , Andrew G. Malis , Stewart Bryant , Jouni Korhonen | ||
| Last updated | 2019-05-06 | ||
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draft-ietf-detnet-ip-over-tsn-00
DetNet B. Varga, Ed.
Internet-Draft J. Farkas
Intended status: Standards Track Ericsson
Expires: November 6, 2019 A. Malis
S. Bryant
Huawei Technologies
J. Korhonen
May 5, 2019
DetNet Data Plane: IP over IEEE 802.1 Time Sensitive Networking (TSN)
draft-ietf-detnet-ip-over-tsn-00
Abstract
This document specifies the Deterministic Networking IP data plane
when operating over a TSN network.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 6, 2019.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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. DetNet IP Data Plane Overview . . . . . . . . . . . . . . . . 4
5. DetNet IP Data Plane Considerations . . . . . . . . . . . . . 7
5.1. DetNet Routers . . . . . . . . . . . . . . . . . . . . . 8
5.2. Networks With Multiple Technology Segments . . . . . . . 9
6. Mapping DetNet IP Flows to IEEE 802.1 TSN . . . . . . . . . . 10
6.1. TSN Stream ID Mapping . . . . . . . . . . . . . . . . . . 11
6.2. TSN Usage of FRER . . . . . . . . . . . . . . . . . . . . 13
6.3. Procedures . . . . . . . . . . . . . . . . . . . . . . . 14
7. Management and Control Implications . . . . . . . . . . . . . 14
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
11.1. Normative references . . . . . . . . . . . . . . . . . . 16
11.2. Informative references . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
1. Introduction
[Editor's note: Introduction to be made specific to DetNet IP over
TSN scenario. May be similar to intro of DetNet MPLS over TSN.].
Deterministic Networking (DetNet) is a service that can be offered by
a network to DetNet flows. DetNet provides these flows extremely low
packet loss rates and assured maximum end-to-end delivery latency.
General background and concepts of DetNet can be found in the DetNet
Architecture [I-D.ietf-detnet-architecture].
This document specifies the DetNet data plane operation for IP hosts
and routers that provide DetNet service to IP encapsulated data. No
DetNet specific encapsulation is defined to support IP flows, rather
existing IP and higher layer protocol header information is used to
support flow identification and DetNet service delivery.
The DetNet Architecture decomposes the DetNet related data plane
functions into two sub-layers: a service sub-layer and a forwarding
sub-layer. The service sub-layer is used to provide DetNet service
protection and reordering. The forwarding sub-layer is used to
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provides congestion protection (low loss, assured latency, and
limited reordering). As no DetNet specific headers are added to
support DetNet IP flows, only the forwarding sub-layer functions are
supported using the DetNet IP defined by this document. Service
protection can be provided on a per sub-net basis using technologies
such as MPLS [I-D.ietf-detnet-dp-sol-mpls] and IEEE802.1 TSN.
2. Terminology
[Editor's note: Needs clean up.].
2.1. Terms Used In This Document
This document uses the terminology and concepts established in the
DetNet architecture [I-D.ietf-detnet-architecture], and the reader is
assumed to be familiar with that document and its terminology.
2.2. Abbreviations
The following abbreviations used in this document:
CE Customer Edge equipment.
CoS Class of Service.
DetNet Deterministic Networking.
DF DetNet Flow.
L2 Layer-2.
L3 Layer-3.
LSP Label-switched path.
MPLS Multiprotocol Label Switching.
OAM Operations, Administration, and Maintenance.
PE Provider Edge.
PREOF Packet Replication, Ordering and Elimination Function.
PSN Packet Switched Network.
PW Pseudowire.
QoS Quality of Service.
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TE Traffic Engineering.
TSN Time-Sensitive Networking, TSN is a Task Group of the
IEEE 802.1 Working Group.
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. DetNet IP Data Plane Overview
[Editor's note: simplify this section and highlight DetNet IP over
subnets scenario being the focus in the remaining part of the
document.].
This document describes how IP is used by DetNet nodes, i.e., hosts
and routers, to identify DetNet flows and provide a DetNet service.
From a data plane perspective, an end-to-end IP model is followed.
As mentioned above, existing IP and higher layer protocol header
information is used to support flow identification and DetNet service
delivery.
DetNet uses "6-tuple" based flow identification, where "6-tuple"
refers to information carried in IP and higher layer protocol
headers. General background on the use of IP headers, and
"5-tuples", to identify flows and support Quality of Service (QoS)
can be found in [RFC3670]. [RFC7657] also provides useful background
on the delivery differentiated services (DiffServ) and "6-tuple"
based flow identification.
DetNet flow aggregation may be enabled via the use of wildcards,
masks, prefixes and ranges. IP tunnels may also be used to support
flow aggregation. In these cases, it is expected that DetNet aware
intermediate nodes will provide DetNet service assurance on the
aggregate through resource allocation and congestion control
mechanisms.
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DetNet IP Relay Relay DetNet IP
End System Node Node End System
+----------+ +----------+
| Appl. |<------------ End to End Service ----------->| Appl. |
+----------+ ............ ........... +----------+
| Service |<-: Service :-- DetNet flow --: Service :->| Service |
+----------+ +----------+ +----------+ +----------+
|Forwarding| |Forwarding| |Forwarding| |Forwarding|
+--------.-+ +-.------.-+ +-.---.----+ +-------.--+
: Link : \ ,-----. / \ ,-----. /
+......+ +----[ Sub ]----+ +-[ Sub ]-+
[Network] [Network]
`-----' `-----'
|<--------------------- DetNet IP --------------------->|
Figure 1: A Simple DetNet (DN) Enabled IP Network
Figure 1 illustrates a DetNet enabled IP network. The DetNet enabled
end systems originate IP encapsulated traffic that is identified as
DetNet flows, relay nodes understand the forwarding requirements of
the DetNet flow and ensure that node, interface and sub-network
resources are allocated to ensure DetNet service requirements. The
dotted line around the Service component of the Relay Nodes indicates
that the transit routers are DetNet service aware but do not perform
any DetNet service sub-layer function, e.g., PREOF. IEEE 802.1 TSN
is an example sub-network type which can provide support for DetNet
flows and service. The mapping of DetNet IP flows to TSN streams and
TSN protection mechanisms is covered in Section 6.
Note: The sub-network can represent a TSN, MPLS or IP network
segment.
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DetNet IP Relay Transit Relay DetNet IP
End System Node Node Node End System
+----------+ +----------+
| Appl. |<-------------- End to End Service ---------->| Appl. |
+----------+ .....-----+ +-----..... +----------+
| Service |<--: Service |-- DetNet flow ---| Service :-->| Service |
| | : |<- DN MPLS flow ->| : | |
+----------+ +---------+ +----------+ +---------+ +----------+
|Forwarding| |Fwd| |Fwd| |Forwarding| |Fwd| |Fwd| |Forwarding|
+--------.-+ +-.-+ +-.-+ +---.----.-+ +-.-+ +-.-+ +----.-----+
: Link : / ,-----. \ : Link : / ,-----. \
+.......+ +-[ Sub ]-+ +.......+ +--[ Sub ]--+
[Network] [Network]
`-----' `-----'
|<---- DetNet MPLS --->|
|<--------------------- DetNet IP ------------------->|
Figure 2: DetNet IP Over DetNet MPLS Network
Figure 2 illustrates a variant of Figure 1, with an MPLS based DetNet
network as a sub-network between the relay nodes. It shows a more
complex DetNet enabled IP network where an IP flow is mapped to one
or more PWs and MPLS (TE) LSPs. The end systems still originate IP
encapsulated traffic that is identified as DetNet flows. The relay
nodes follow procedures defined in RRR to map each DetNet flow to
MPLS LSPs. While not shown, relay nodes can provide service sub-
layer functions such as PREOF using DetNet over MPLS, and this is
indicated by the solid line for the MPLS facing portion of the
Service component. Note that the Transit node is MPLS (TE) LSP aware
and performs switching based on MPLS labels, and need not have any
specific knowledge of the DetNet service or the corresponding DetNet
flow identification. See RRR for details on the mapping of IP flows
to MPLS, and [I-D.ietf-detnet-dp-sol-mpls] for general support of
DetNet services using MPLS.
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IP Edge Edge IP
End System Node Node End System
+----------+ +.........+ +.........+ +----------+
| Appl. |<--:Svc Proxy:-- E2E Service ---:Svc Proxy:-->| Appl. |
+----------+ +.........+ +.........+ +----------+
| IP |<--:IP : :Svc:----- IP flow ----:Svc: :IP :-->| IP |
+----------+ +---+ +---+ +---+ +---+ +----------+
|Forwarding| |Fwd| |Fwd| |Fwd| |Fwd| |Forwarding|
+--------.-+ +-.-+ +-.-+ +-.-+ +-.-+ +---.------+
: Link : \ ,-----. / / ,-----. \
+.......+ +-----[ Sub ]----+ +--[ Sub ]--+
[Network] [Network]
`-----' `-----'
|<--- IP --->| |<------ DetNet IP ------->| |<--- IP --->|
Figure 3: Non-DetNet aware IP end systems with DetNet IP Domain
Figure 3 illustrates another variant of Figure 1 where the end
systems are not DetNet aware. In this case, edge nodes sit at the
boundary of the DetNet domain and provide DetNet service proxies for
the end applications by initiating and terminating DetNet service for
the application's IP flows. The existing header information or an
approach used for aggregation can be used to support DetNet flow
identification.
Non-DetNet and DetNet IP packets are identical on the wire. From
data plane perspective, the only difference is that there is flow-
associated DetNet information on each DetNet node that defines the
flow related characteristics and required forwarding behavior. As
shown above, edge nodes provide a Service Proxy function that
"associates" one or more IP flows with the appropriate DetNet flow-
specific information and ensures that the receives the proper traffic
treatment within the domain.
Note: The operation of IEEE802.1 TSN end systems over DetNet enabled
IP networks is not described in this document. While TSN flows could
be encapsulated in IP packets by an IP End System or DetNet Edge Node
in order to produce DetNet IP flows, the details of such are out of
scope of this document.
5. DetNet IP Data Plane Considerations
[Editor's note: Sort out what data plane considerations are relevant
for sub-net scenarios.].
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5.1. DetNet Routers
Within a DetNet domain, the DetNet enabled IP Routers interconnect
links and sub-networks to support end-to-end delivery of DetNet
flows. From a DetNet architecture perspective, these routers are
DetNet relays, as they must be DetNet service aware. Such routers
identify DetNet flows based on the IP 6-tuple, and ensure that the
DetNet service required traffic treatment is provided both on the
node and on any attached sub-network.
This solution provides DetNet functions end to end, but does so on a
per link and sub-network basis. Congestion protection and latency
control and the resource allocation (queuing, policing, shaping) are
supported using the underlying link / sub net specific mechanisms.
However, service protections (packet replication and packet
elimination functions) are not provided at the DetNet layer end to
end. But such service protection can be provided on a per underlying
L2 link and sub-network basis.
+------+ +------+
| X | | X |
+======+ +------+
End-system | IP | | IP |
-----+------+-------+======+--- --+======+--
DetNet |L2/SbN| |L2/SbN|
+------+ +------+
Figure 4: Encapsulation of DetNet Routing in simplified IP service L3
end-systems
The DetNet Service Flow is mapped to the link / sub-network specific
resources using an underlying system specific means. This implies
each DetNet aware node on path looks into the forwarded DetNet
Service Flow packet and utilize e.g., a 5- (or 6-) tuple to find out
the required mapping within a node.
As noted earlier, the Service Protection is done within each link /
sub-network independently using the domain specific mechanisms (due
the lack of a unified end to end sequencing information that would be
available for intermediate nodes). Therefore, service protection (if
any) cannot be provided end-to-end, only within sub-networks. This
is shown for a three sub-network scenario in Figure 5, where each
sub-network can provide service protection between its borders.
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______
____ / \__
____ / \__/ \___ ______
+----+ __/ +====+ +==+ \ +----+
|src |__/ SubN1 ) | | \ SubN3 \____| dst|
+----+ \_______/ \ Sub-Network2 | \______/ +----+
\_ _/
\ __ __/
\_______/ \___/
+---+ +---------E--------+ +-----+
+----+ | | | | | | | +----+
|src |----R E--------R +---+ E------R E------+ dst|
+----+ | | | | | | | +----+
+---+ +-----R------------+ +-----+
Figure 5: Replication and elimination in sub-networks for DetNet IP
networks
If end to end service protection is desired that can be implemented,
for example, by the DetNet end systems using Layer-4 (L4) transport
protocols or application protocols. However, these are out of scope
of this document.
5.2. Networks With Multiple Technology Segments
There are network scenarios, where the DetNet domain contains
multiple technology segments (IEEE 802.1 TSN, MPLS) and all those
segments are under the same administrative control (see Figure 6).
Furthermore, DetNet nodes may be interconnected via TSN segments.
DetNet routers ensure that detnet service requirements are met per
hop by allocating local resources, both receive and transmit, and by
mapping the service requirements of each flow to appropriate sub-
network mechanisms. Such mapping is sub-network technology specific.
The mapping of DetNet IP Flows to MPLS is covered RRR . The mapping
of IP DetNet Flows to IEEE 802.1 TSN is covered in Section 6.
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______
_____ / \__
____ / \__/ \___ ______
+----+ __/ +======+ +==+ \ +----+
|src |__/ Seg1 ) | | \ Seg3 \__| dst|
+----+ \_______+ \ Segment-2 | \+_____/ +----+
\======+__ _+===/
\ __ __/
\_______/ \___/
Figure 6: DetNet domains and multiple technology segments
6. Mapping DetNet IP Flows to IEEE 802.1 TSN
[Authors note: how do we handle control protocols such as ICMP,
IPsec, etc.]
This section covers how DetNet IP flows operate over an IEEE 802.1
TSN sub-network. Figure 7 illustrates such a scenario, where two IP
(DetNet) nodes are interconnected by a TSN sub-network. Node-1 is
single homed and Node-2 is dual-homed. IP nodes can be (1) DetNet IP
End System, (2) DetNet IP Edge or Relay node or (3) IP End System.
IP (DetNet) IP (DetNet)
Node-1 Node-2
............ ............
<--: Service :-- DetNet flow ---: Service :-->
+----------+ +----------+
|Forwarding| |Forwarding|
+--------.-+ <-TSN Str-> +-.-----.--+
\ ,-------. / /
+----[ TSN-Sub ]---+ /
[ Network ]--------+
`-------'
<----------------- DetNet IP ----------------->
Figure 7: DetNet (DN) Enabled IP Network over a TSN sub-network
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 provide 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.
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As is the case for DetNet, a Layer 2 network node such as a bridge
may need to identify the specific DetNet flow to which a packet
belongs in order to provide the TSN/DetNet QoS for that packet. It
also may need additional marking, such as the priority field of an
IEEE Std 802.1Q VLAN tag, to give the packet proper service.
TSN capabilities of the TSN sub-network are made available for IP
(DetNet) flows via the protocol interworking function defined in IEEE
802.1CB [IEEE8021CB]. For example, applied on the TSN edge port
connected to the IP (DetNet) node it can convert an ingress unicast
IP (DetNet) flow to use a specific multicast destination MAC address
and VLAN, in order to direct the packet through a specific path
inside the bridged network. A similar interworking pair at the other
end of the TSN sub-network would restore the packet to its original
destination MAC address and VLAN.
Placement of TSN functions depends on the TSN capabilities of nodes.
IP (DetNet) Nodes may or may not support TSN functions. For a given
TSN Stream (i.e., DetNet flow) an IP (DetNet) node is treated as a
Talker or a Listener inside the TSN sub-network.
6.1. TSN Stream ID Mapping
DetNet IP Flow and TSN Stream mapping is based on the active Stream
Identification function, that operates at the frame level. IEEE
802.1CB [IEEE8021CB] defines an Active Destination MAC and VLAN
Stream identification function, what can replace some Ethernet header
fields namely (1) the destination MAC-address, (2) the VLAN-ID and
(3) priority parameters with alternate values. Replacement is
provided for the frame passed down the stack from the upper layers or
up the stack from the lower layers.
Active Destination MAC and VLAN Stream identification can be used
within a Talker to set flow identity or a Listener to recover the
original addressing information. It can be used also in a TSN bridge
that is providing translation as a proxy service for an End System.
As a result IP (DetNet) flows can be mapped to use a particular {MAC-
address, VLAN} pair to match the Stream in the TSN sub-network.
From the TSN sub-network perspective DetNet IP nodes without any TSN
functions can be treated as TSN-unaware Talker or Listener. In such
cases relay nodes in the TSN sub-network MUST modify the Ethernet
encapsulation of the DetNet IP flow (e.g., MAC translation, VLAN-ID
setting, Sequence number addition, etc.) to allow proper TSN specific
handling of the flow inside the sub-network. This is illustrated in
Figure 8.
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IP (DetNet)
Node-1
<---------->
............
<--: Service :-- DetNet flow ------------------
+----------+
|Forwarding|
+----------+ +---------------+
| L2 | | L2 Relay with |<--- TSN ----
| | | TSN function | Stream
+-----.----+ +--.---------.--+
\__________/ \______
TSN-unaware
Talker / TSN-Bridge
Listener Relay
<-------- TSN sub-network -------
Figure 8: IP (DetNet) node without TSN functions
IP (DetNet) nodes being TSN-aware can be treated as a combination of
a TSN-unaware Talker/Listener and a TSN-Relay, as shown in Figure 9.
In such cases the IP (DetNet) node MUST provide the TSN sub-network
specific Ethernet encapsulation over the link(s) towards the sub-
network. An TSN-aware IP (DetNet) node MUST support the following
TSN components:
1. For recognizing flows:
* Stream Identification
2. For FRER used inside the TSN domain, additionally:
* Sequencing function
* Sequence encode/decode function
3. For FRER when the node is a replication or elimination point,
additionally:
* Stream splitting function
* Individual recovery function
[Editor's note: Should we added here requirements regarding IEEE
802.1Q C-VLAN component?]
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IP (DetNet)
Node-2
<---------------------------------->
............
<--: Service :-- DetNet flow ------------------
+----------+
|Forwarding|
+----------+ +---------------+
| L2 | | L2 Relay with |<--- TSN ---
| | | TSN function | Stream
+-----.----+ +--.------.---.-+
\__________/ \ \______
\_________
TSN-unaware
Talker / TSN-Bridge
Listener Relay
<----- TSN Sub-network -----
<------- TSN-aware Tlk/Lstn ------->
Figure 9: IP (DetNet) node with TSN functions
A Stream identification component MUST be able to instantiate the
following functions (1) Active Destination MAC and VLAN Stream
identification function, (2) IP Stream identification function and
(3) the related managed objects in Clause 9 of IEEE 802.1CB
[IEEE8021CB]. IP Stream identification function provides a 6-tuple
match.
The Sequence encode/decode function MUST support the Redundancy tag
(R-TAG) format as per Clause 7.8 of IEEE 802.1CB [IEEE8021CB].
6.2. TSN Usage of FRER
TSN Streams supporting DetNet flows may use Frame Replication and
Elimination for Redundancy (FRER) [802.1CB] based on the loss service
requirements of the TSN Stream, which is derived from the DetNet
service requirements of the DetNet mapped flow. The specific
operation of FRER is not modified by the use of DetNet and follows
IEEE 802.1CB [IEEE8021CB].
FRER function and the provided service recovery is available only
within the TSN sub-network (as shown in Figure 5) as the Stream-ID
and the TSN sequence number are not valid outside the sub-network.
An IP (DetNet) node represents a L3 border and as such it terminates
all related information elements encoded in the L2 frames.
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6.3. Procedures
[Editor's note: This section is TBD - covers required behavior of a
TSN-aware DetNet node using a TSN underlay.]
This section provides DetNet IP data plane procedures to interwork
with a TSN underlay sub-network when the IP (DetNet) node acts as a
TSN-aware Talker or Listener (see Figure 9). These procedures have
been divided into the following areas: flow identification, mapping
of a DetNet flow to a TSN Stream and ensure proper TSN encapsulation.
Flow identification procedures are described in RRR . A TSN-aware IP
(DetNet) node SHALL support the Stream Identification TSN components
as per IEEE 802.1CB [IEEE8021CB].
Implementations of this document SHALL use management and control
information to map a DetNet flow to a TSN Stream. N:1 mapping
(aggregating DetNet flows in a single TSN Stream) SHALL be supported.
The management or control function that provisions flow mapping SHALL
ensure that adequate resources are allocated and configured to
provide proper service requirements of the mapped flows.
For proper TSN encapsulation implementations of this document SHALL
support active Stream Identification function as defined in chapter
6.6 in IEEE 802.1CB [IEEE8021CB].
A TSN-aware IP (DetNet) node SHALL support Ethernet encapsulation
with Redundancy tag (R-TAG) as per chapter 7.8 in IEEE 802.1CB
[IEEE8021CB].
Depending whether FRER functions are used in the TSN sub-network to
serve the mapped TSN Stream, a TSN-aware IP (DetNet) node SHALL
support Sequencing function and Sequence encode/decode function as
per chapter 7.4 and 7.6 in IEEE 802.1CB [IEEE8021CB]. Furthermore
when a TSN-aware IP (DetNet) node acting as a replication or
elimination point for FRER it SHALL implement the Stream splitting
function and the Individual recovery function as per chapter 7.7 and
7.5 in IEEE 802.1CB [IEEE8021CB].
7. Management and Control Implications
[Editor's note: This section is TBD Covers Creation, mapping, removal
of TSN Stream IDs, related parameters and,when needed, configuration
of FRER. Supported by management/control plane.]
DetNet flow and TSN Stream mapping related information are required
only for TSN-aware IP (DetNet) nodes. From the Data Plane
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perspective there is no practical difference based on the origin of
flow mapping related information (management plane or control plane).
TSN-aware DetNet IP nodes are member of both the DetNet domain and
the TSN sub-network. Within the TSN sub-network the TSN-aware IP
(DetNet) node has a TSM-aware Talker/Listener 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 and TSN is required.
In order to use a TSN sub-network between DetNet nodes, DetNet
specific information must be converted to TSN sub-network specific
ones. DetNet flow ID and flow related parameters/requirements must
be converted to a TSN Stream ID and stream related parameters/
requirements. Note that, as the TSN sub-network is just a portion of
the end2end DetNet path (i.e., single hop from IP perspective), some
parameters (e.g., delay) may differ significantly. Other parameters
(like bandwidth) also may have to be tuned due to the L2
encapsulation used in the TSN sub-network.
In some case it may be challenging to determine some TSN Stream
related information. For example on a TSN-aware IP (DetNet) node
that acts as a Talker, it is quite obvious which DetNet node is the
Listener of the mapped TSN stream (i.e., the IP Next-Hop). 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 and TSN domains.
Mapping between DetNet flow identifiers and TSN Stream identifiers,
if not provided explicitly, can be done by a TSN-aware IP (DetNet)
node locally based on information provided for configuration of the
TSN Stream identification functions (IP Stream identification and
active Stream identification function).
Triggering the setup/modification of a TSN Stream in the TSN sub-
network is an example where management and/or control plane
interactions are required between the DetNet and TSN sub-network.
TSN-unaware IP (DetNet) nodes make such a triggering even more
complicated as they are fully unaware of the sub-network and run
independently.
Configuration of TSN specific functions (e.g., FRER) inside the TSN
sub-network is a TSN specific decision and may not be visible in the
DetNet domain.
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8. Security Considerations
The security considerations of DetNet in general are discussed in
[I-D.ietf-detnet-architecture] and [I-D.ietf-detnet-security]. Other
security considerations will be added in a future version of this
draft.
9. IANA Considerations
TBD.
10. Acknowledgements
Thanks for Norman Finn and Lou Berger for their comments and
contributions.
11. References
11.1. Normative references
[RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768,
DOI 10.17487/RFC0768, August 1980,
<https://www.rfc-editor.org/info/rfc768>.
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>.
[RFC0793] Postel, J., "Transmission Control Protocol", STD 7,
RFC 793, DOI 10.17487/RFC0793, September 1981,
<https://www.rfc-editor.org/info/rfc793>.
[RFC1812] Baker, F., Ed., "Requirements for IP Version 4 Routers",
RFC 1812, DOI 10.17487/RFC1812, June 1995,
<https://www.rfc-editor.org/info/rfc1812>.
[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>.
[RFC2211] Wroclawski, J., "Specification of the Controlled-Load
Network Element Service", RFC 2211, DOI 10.17487/RFC2211,
September 1997, <https://www.rfc-editor.org/info/rfc2211>.
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[RFC2212] Shenker, S., Partridge, C., and R. Guerin, "Specification
of Guaranteed Quality of Service", RFC 2212,
DOI 10.17487/RFC2212, September 1997,
<https://www.rfc-editor.org/info/rfc2212>.
[RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black,
"Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers", RFC 2474,
DOI 10.17487/RFC2474, December 1998,
<https://www.rfc-editor.org/info/rfc2474>.
[RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
of Explicit Congestion Notification (ECN) to IP",
RFC 3168, DOI 10.17487/RFC3168, September 2001,
<https://www.rfc-editor.org/info/rfc3168>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/info/rfc3209>.
[RFC3270] Le Faucheur, F., Wu, L., Davie, B., Davari, S., Vaananen,
P., Krishnan, R., Cheval, P., and J. Heinanen, "Multi-
Protocol Label Switching (MPLS) Support of Differentiated
Services", RFC 3270, DOI 10.17487/RFC3270, May 2002,
<https://www.rfc-editor.org/info/rfc3270>.
[RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label
Switching (GMPLS) Signaling Resource ReserVation Protocol-
Traffic Engineering (RSVP-TE) Extensions", RFC 3473,
DOI 10.17487/RFC3473, January 2003,
<https://www.rfc-editor.org/info/rfc3473>.
[RFC4302] Kent, S., "IP Authentication Header", RFC 4302,
DOI 10.17487/RFC4302, December 2005,
<https://www.rfc-editor.org/info/rfc4302>.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, DOI 10.17487/RFC4303, December 2005,
<https://www.rfc-editor.org/info/rfc4303>.
[RFC5462] Andersson, L. and R. Asati, "Multiprotocol Label Switching
(MPLS) Label Stack Entry: "EXP" Field Renamed to "Traffic
Class" Field", RFC 5462, DOI 10.17487/RFC5462, February
2009, <https://www.rfc-editor.org/info/rfc5462>.
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[RFC6003] Papadimitriou, D., "Ethernet Traffic Parameters",
RFC 6003, DOI 10.17487/RFC6003, October 2010,
<https://www.rfc-editor.org/info/rfc6003>.
[RFC7608] Boucadair, M., Petrescu, A., and F. Baker, "IPv6 Prefix
Length Recommendation for Forwarding", BCP 198, RFC 7608,
DOI 10.17487/RFC7608, July 2015,
<https://www.rfc-editor.org/info/rfc7608>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
11.2. Informative references
[G.8275.1]
International Telecommunication Union, "Precision time
protocol telecom profile for phase/time synchronization
with full timing support from the network", ITU-T
G.8275.1/Y.1369.1 G.8275.1, June 2016,
<https://www.itu.int/rec/T-REC-G.8275.1/en>.
[G.8275.2]
International Telecommunication Union, "Precision time
protocol telecom profile for phase/time synchronization
with partial timing support from the network", ITU-T
G.8275.2/Y.1369.2 G.8275.2, June 2016,
<https://www.itu.int/rec/T-REC-G.8275.2/en>.
[I-D.ietf-detnet-architecture]
Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", draft-ietf-
detnet-architecture-12 (work in progress), March 2019.
[I-D.ietf-detnet-dp-sol-mpls]
Korhonen, J. and B. Varga, "DetNet MPLS Data Plane
Encapsulation", draft-ietf-detnet-dp-sol-mpls-02 (work in
progress), March 2019.
[I-D.ietf-detnet-flow-information-model]
Farkas, J., Varga, B., Cummings, R., and Y. Jiang, "DetNet
Flow Information Model", draft-ietf-detnet-flow-
information-model-03 (work in progress), March 2019.
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[I-D.ietf-detnet-security]
Mizrahi, T., Grossman, E., Hacker, A., Das, S., Dowdell,
J., Austad, H., Stanton, K., and N. Finn, "Deterministic
Networking (DetNet) Security Considerations", draft-ietf-
detnet-security-04 (work in progress), March 2019.
[I-D.ietf-teas-pce-native-ip]
Wang, A., Zhao, Q., Khasanov, B., Chen, H., and R. Mallya,
"PCE in Native IP Network", draft-ietf-teas-pce-native-
ip-03 (work in progress), April 2019.
[IEEE1588]
IEEE, "IEEE 1588 Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and
Control Systems Version 2", 2008.
[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/>.
[RFC1122] Braden, R., Ed., "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122,
DOI 10.17487/RFC1122, October 1989,
<https://www.rfc-editor.org/info/rfc1122>.
[RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
September 1997, <https://www.rfc-editor.org/info/rfc2205>.
[RFC2386] Crawley, E., Nair, R., Rajagopalan, B., and H. Sandick, "A
Framework for QoS-based Routing in the Internet",
RFC 2386, DOI 10.17487/RFC2386, August 1998,
<https://www.rfc-editor.org/info/rfc2386>.
[RFC3670] Moore, B., Durham, D., Strassner, J., Westerinen, A., and
W. Weiss, "Information Model for Describing Network Device
QoS Datapath Mechanisms", RFC 3670, DOI 10.17487/RFC3670,
January 2004, <https://www.rfc-editor.org/info/rfc3670>.
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[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
<https://www.rfc-editor.org/info/rfc5575>.
[RFC5654] Niven-Jenkins, B., Ed., Brungard, D., Ed., Betts, M., Ed.,
Sprecher, N., and S. Ueno, "Requirements of an MPLS
Transport Profile", RFC 5654, DOI 10.17487/RFC5654,
September 2009, <https://www.rfc-editor.org/info/rfc5654>.
[RFC5777] Korhonen, J., Tschofenig, H., Arumaithurai, M., Jones, M.,
Ed., and A. Lior, "Traffic Classification and Quality of
Service (QoS) Attributes for Diameter", RFC 5777,
DOI 10.17487/RFC5777, February 2010,
<https://www.rfc-editor.org/info/rfc5777>.
[RFC6434] Jankiewicz, E., Loughney, J., and T. Narten, "IPv6 Node
Requirements", RFC 6434, DOI 10.17487/RFC6434, December
2011, <https://www.rfc-editor.org/info/rfc6434>.
[RFC7551] Zhang, F., Ed., Jing, R., and R. Gandhi, Ed., "RSVP-TE
Extensions for Associated Bidirectional Label Switched
Paths (LSPs)", RFC 7551, DOI 10.17487/RFC7551, May 2015,
<https://www.rfc-editor.org/info/rfc7551>.
[RFC7657] Black, D., Ed. and P. Jones, "Differentiated Services
(Diffserv) and Real-Time Communication", RFC 7657,
DOI 10.17487/RFC7657, November 2015,
<https://www.rfc-editor.org/info/rfc7657>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8169] Mirsky, G., Ruffini, S., Gray, E., Drake, J., Bryant, S.,
and A. Vainshtein, "Residence Time Measurement in MPLS
Networks", RFC 8169, DOI 10.17487/RFC8169, May 2017,
<https://www.rfc-editor.org/info/rfc8169>.
[RFC8283] Farrel, A., Ed., Zhao, Q., Ed., Li, Z., and C. Zhou, "An
Architecture for Use of PCE and the PCE Communication
Protocol (PCEP) in a Network with Central Control",
RFC 8283, DOI 10.17487/RFC8283, December 2017,
<https://www.rfc-editor.org/info/rfc8283>.
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Authors' Addresses
Balazs Varga (editor)
Ericsson
Magyar Tudosok krt. 11.
Budapest 1117
Hungary
Email: balazs.a.varga@ericsson.com
Janos Farkas
Ericsson
Magyar Tudosok krt. 11.
Budapest 1117
Hungary
Email: janos.farkas@ericsson.com
Andrew G. Malis
Huawei Technologies
Email: agmalis@gmail.com
Stewart Bryant
Huawei Technologies
Email: stewart.bryant@gmail.com
Jouni Korhonen
Email: jouni.nospam@gmail.com
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