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draft-ietf-detnet-tsn-vpn-over-mpls.xml
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<?xml version="1.0" encoding="US-ASCII"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd" [
<!ENTITY rfc2119 PUBLIC "" "http://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml">
<!ENTITY rfc3031 PUBLIC "" "http://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.3031.xml">
<!ENTITY rfc3985 PUBLIC "" "http://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.3985.xml">
<!ENTITY rfc5921 PUBLIC "" "http://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.5921.xml">
<!ENTITY rfc8660 PUBLIC "" "http://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8660.xml">
]>
<?xml-stylesheet type='text/xsl' href='rfc2629.xslt' ?>
<?rfc toc="yes"?>
<?rfc symrefs="yes"?>
<?rfc sortrefs="yes"?>
<?rfc iprnotified="no"?>
<?rfc strict="yes"?>
<?rfc compact="yes"?>
<?rfc subcompact="no"?>
<rfc category="std"
docName="draft-ietf-detnet-tsn-vpn-over-mpls-03"
ipr="trust200902"
submissionType="IETF">
<front>
<title abbrev="TSN over DetNet MPLS">
DetNet Data Plane: IEEE 802.1 Time Sensitive Networking over MPLS</title>
<author role="editor" fullname="Balázs Varga" initials="B." surname="Varga">
<organization>Ericsson</organization>
<address>
<postal>
<street>Magyar Tudosok krt. 11.</street>
<city>Budapest</city>
<country>Hungary</country>
<code>1117</code>
</postal>
<email>[email protected]</email>
</address>
</author>
<author fullname="János Farkas" initials="J." surname="Farkas">
<organization>Ericsson</organization>
<address>
<postal>
<street>Magyar Tudosok krt. 11.</street>
<city>Budapest</city>
<country>Hungary</country>
<code>1117</code>
</postal>
<email>[email protected]</email>
</address>
</author>
<author fullname="Andrew G. Malis" initials="A.G." surname="Malis">
<organization>Malis Consulting</organization>
<address>
<email>[email protected]</email>
</address>
</author>
<author fullname="Stewart Bryant" initials="S." surname="Bryant">
<organization>Futurewei Technologies</organization>
<address>
<email>[email protected]</email>
</address>
</author>
<author fullname="Don Fedyk" initials="D." surname="Fedyk">
<organization>LabN Consulting, L.L.C.</organization>
<address>
<email>[email protected]</email>
</address>
</author>
<date />
<workgroup>DetNet</workgroup>
<abstract>
<t>
This document specifies the Deterministic Networking data plane
when TSN networks are interconnected over a DetNet MPLS Network.
</t>
</abstract>
</front>
<middle>
<section title="Introduction" anchor="sec_intro">
<t>
The Time-Sensitive Networking Task Group (TSN TG) within IEEE 802.1 Working
Group deals with deterministic services through IEEE 802 networks.
Deterministic Networking (DetNet) defined by IETF is a service that can be
offered by a L3 network to DetNet flows. General background and concepts
of DetNet can be found in <xref target="RFC8655"/>.
</t>
<t>
This document specifies the use of a DetNet MPLS network to interconnect TSN
nodes/network segments. DetNet MPLS data plane is defined in
<xref target="I-D.ietf-detnet-mpls"/>.
<vspace blankLines="100" /> </t>
</section>
<section title="Terminology">
<section title="Terms Used in This Document">
<t>
This document uses the terminology and concepts established in the DetNet
architecture <xref target="RFC8655"/> and
<xref target="I-D.ietf-detnet-data-plane-framework"/>, and
<xref target="I-D.ietf-detnet-mpls"/>. The reader is assumed
to be familiar with these documents and their terminology.
</t>
</section>
<section title="Abbreviations">
<t>
The following abbreviations are used in this document:
<list style="hanging" hangIndent="14">
<t hangText="AC">Attachment Circuit.</t>
<t hangText="CE">Customer Edge equipment.</t>
<t hangText="CW">Control Word.</t>
<t hangText="DetNet">Deterministic Networking.</t>
<t hangText="DF">DetNet Flow.</t>
<t hangText="FRER">Frame Replication and Elimination for Redundancy
(TSN function).</t>
<t hangText="L2">Layer 2.</t>
<t hangText="L2VPN">Layer 2 Virtual Private Network.</t>
<t hangText="L3">Layer 3.</t>
<t hangText="LSR">Label Switching Router.</t>
<t hangText="MPLS">Multiprotocol Label Switching.</t>
<t hangText="MPLS-TE">Multiprotocol Label Switching - Traffic Engineering.</t>
<t hangText="MPLS-TP">Multiprotocol Label Switching - Transport Profile.</t>
<t hangText="NSP">Native Service Processing.</t>
<t hangText="OAM">Operations, Administration, and Maintenance.</t>
<t hangText="PE">Provider Edge.</t>
<t hangText="PREOF">Packet Replication, Elimination and Ordering Functions.</t>
<t hangText="PW">PseudoWire.</t>
<t hangText="S-PE">Switching Provider Edge.</t>
<t hangText="T-PE">Terminating Provider Edge.</t>
<t hangText="TSN">Time-Sensitive Network.</t>
</list>
</t>
</section>
<section title="Requirements Language">
<t>
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 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and
only when, they appear in all capitals, as shown here.
</t>
</section>
</section> <!-- end of terminology -->
<!-- =========================================== -->
<!-- TSN over DetNet MPLS -->
<!-- =========================================== -->
<section title="IEEE 802.1 TSN Over DetNet MPLS Data Plane Scenario"
anchor="sec_tsn_mpls_dt_dp_scen">
<t>
<xref target="fig_tsn_mpls_detnet"/> shows IEEE 802.1 TSN end
stations operating over a TSN aware DetNet service running over an MPLS
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. These are functionally similar to pseudowire (PW)
Terminating Provider Edge (T-PE) nodes which use MPLS-TE LSPs. In this
example TSN Streams are simple applications over DetNet flows. The specific
of this operation are discussed later in this document.
</t>
<figure anchor="fig_tsn_mpls_detnet" align="center"
title="A TSN over DetNet MPLS Enabled Network">
<artwork align="center"><![CDATA[
TSN Edge Transit Edge TSN
End System Node Node Node End System
(T-PE) (LSR) (T-PE)
+----------+ +----------+
| TSN | <---------End to End TSN Service----------> | TSN |
| Applic. | | Applic. |
+----------+ +.........+ +.........+ +----------+
| | | \S-Proxy: :S-Proxy/ | | |
| TSN | | +.+---+<-- DetNet flow -->+---+ | | | TSN |
| | |TSN| |Svc| |Svc| |TSN| | |
+----------+ +---+ +---+ +----------+ +---+ +---+ +----------+
| L2 | | L2| |Fwd| |Forwarding| |Fwd| |L2 | | L2 |
+------.---+ +-.-+ +-.-+ +---.----.-+ +--.+ +-.-+ +---.------+
: Link : / ,-----. \ : Link : / ,-----. \
+........+ +-[ Sub ]-+ +........+ +-[ TSN ]-+
[Network] [Network]
`-----' `-----'
|<------ DetNet MPLS ------>|
|<---------------------- TSN --------------------->|
]]></artwork>
</figure>
<t>
In this example, edge nodes provide a service proxy function that
"associates" the DetNet flows and native flows (i.e., TSN Streams) at
the edge of the DetNet domain. TSN streams are treated as App-flows
for DetNet. The whole DetNet domain behaves as a TSN relay node for
the TSN streams. The service proxy behaves as a port of that TSN
relay node.
</t>
<t>
<xref target="fig_8021_detnet"/> illustrates how DetNet can provide services
for IEEE 802.1 TSN end systems, CE1 and CE2, over a DetNet enabled MPLS
network. Edge nodes, E1 and E2, insert and remove required DetNet data
plane encapsulation. The 'X' in the edge nodes and relay node, R1,
represent a potential DetNet compound flow packet replication and
elimination point. This conceptually parallels L2VPN services, and could
leverage existing related solutions as discussed below.
</t>
<figure align="center" anchor="fig_8021_detnet"
title="IEEE 802.1TSN Over DetNet">
<artwork><![CDATA[
TSN |<------- End to End DetNet Service ------>| TSN
Service | Transit Transit | Service
TSN (AC) | |<-Tnl->| |<-Tnl->| | (AC) TSN
End | V V 1 V V 2 V V | End
System | +--------+ +--------+ +--------+ | System
+---+ | | E1 |=======| R1 |=======| E2 | | +---+
| |--|----|._X_....|..DF1..|.._ _...|..DF3..|...._X_.|---|---| |
|CE1| | | \ | | X | | / | | |CE2|
| | | \_.|..DF2..|._/ \_..|..DF4..|._/ | | |
+---+ | |=======| |=======| | +---+
^ +--------+ +--------+ +--------+ ^
| Edge Node Relay Node Edge Node |
| (T-PE) (S-PE) (T-PE) |
| |
|<- TSN -> <------- TSN Over DetNet MPLS -------> <- TSN ->|
| |
|<-------- Time Sensitive Networking (TSN) Service ------->|
X = Service protection
DFx = DetNet member flow x over a TE LSP
]]>
</artwork>
</figure>
</section>
<!-- ================================================= -->
<!-- DetNet MPLS data plane OVERVIEW -->
<!-- ================================================= -->
<section title="DetNet MPLS Data Plane" anchor="sec_dt_dp">
<section title="Overview" anchor="sec_dt_dp_ov">
<t>
The basic approach defined in <xref target="I-D.ietf-detnet-mpls"/>
supports the DetNet service sub-layer based on existing pseudowire (PW)
encapsulations and mechanisms, and supports the DetNet forwarding
sub-layer based on existing MPLS Traffic Engineering encapsulations
and mechanisms.
</t>
<t>
A node operating on a DetNet flow in the Detnet service sub-layer, i.e.
a node processing a DetNet packet which has the S-Label as top of stack
uses the local context associated with that S-Label, for example a received
F-Label, to determine what local DetNet operation(s) are applied to that
packet. An S-Label may be unique when taken from the platform
label space <xref target="RFC3031"/>, which would enable correct DetNet flow
identification regardless of which input interface or LSP the packet arrives
on. The service sub-layer functions (i.e., PREOF) use a DetNet control word
(d-CW).
</t>
<t>
The DetNet MPLS data plane builds on MPLS Traffic Engineering
encapsulations and mechanisms to provide a forwarding sub-layer that
is responsible for providing resource allocation and explicit
routes. The forwarding sub-layer is supported by one or more
forwarding labels (F-Labels).
</t>
<t>
DetNet edge/relay nodes are DetNet service sub-layer
aware, understand the particular needs of DetNet flows and
provide both DetNet service and forwarding sub-layer functions.
They add, remove and process d-CWs, S-Labels and F-labels as
needed. MPLS enabled DetNet nodes can enhance the
reliability of delivery by enabling the replication of packets
where multiple copies, possibly over multiple paths, are
forwarded through the DetNet domain. They can also eliminate
surplus previously replicated copies of DetNet packets.
MPLS (DetNet) nodes also include
DetNet forwarding sub-layer functions, support for notably
explicit routes, and resources allocation to eliminate (or
reduce) congestion loss and jitter.
</t>
<t>
DetNet transit nodes reside wholly within a DetNet domain, and
also provide DetNet forwarding sub-layer functions in accordance
with the performance required by a DetNet flow carried over an
LSP. Unlike other DetNet node types, transit nodes provide no
service sub-layer processing.
</t>
</section>
<section anchor="tom-encap"
title="TSN over DetNet MPLS Encapsulation">
<t>
The basic encapsulation approach is to treat a TSN Stream as an App-flow
from the DetNet MPLS perspective. The corresponding example shown in
<xref target="fig_tsn_mpls_ex"/>.
</t>
<figure title="Example TSN over MPLS Encapsulation Formats"
anchor="fig_tsn_mpls_ex">
<artwork align="center"><![CDATA[
/-> +------+ +------+ +------+ TSN ^ ^
| | X | | X | | X |<- Appli : :
App-Flow <-+ +------+ +------+ +------+ cation : :(1)
for MPLS | |TSN-L2| |TSN-L2| |TSN-L2| : v
\-> +---+======+--+======+--+======+-----+ :
| d-CW | | d-CW | | d-CW | :
DetNet-MPLS +------+ +------+ +------+ :(2)
|Labels| |Labels| |Labels| v
+---+======+--+======+--+======+-----+
Link/Sub-Network | L2 | | TSN | | UDP |
+------+ +------+ +------+
| IP |
+------+
| L2 |
+------+
(1) TSN Stream
(2) DetNet MPLS Flow
]]>
</artwork>
</figure>
<t>
In the figure, "Application" indicates the application payload carried by
the TSN network. "MPLS App-Flow" indicates that the TSN Stream is the
payload from the perspective of the DetNet MPLS data plane defined in
<xref target="I-D.ietf-detnet-mpls"/>. A single DetNet MPLS flow
can aggregate multiple TSN Streams.
</t>
</section>
</section> <!-- end of DetNet MPLS data plane overview -->
<!-- ================================================= -->
<!-- TSN over DetNet MPLS procedures -->
<!-- ================================================= -->
<section title="TSN over MPLS Data Plane Procedures" anchor="tom_proc">
<t>
Description of Edge Nodes procedures and functions for TSN over DetNet MPLS
scenario follows the concept of <xref target="RFC3985"/> and covers the
Edge Nodes components shown on <xref target="fig_tsn_mpls_detnet"/>. In
this section the following procedures of DetNet Edge Nodes are described:
<list style="symbols">
<t>
TSN related (<xref target="tom_tsn_proc"/>)
</t><t>
DetNet Service Proxy (<xref target="tom_svc_prx_proc"/>)
</t><t>
DetNet service and forwarding sub-layer (<xref target="tom_dn_sub_proc"/>)
</t>
</list>
</t>
<t>
The sub-sections describe procedures for forwarding packets by DetNet
Edge nodes, where such packets are received from either directly
connected CEs (TSN nodes) or some other DetNet Edge nodes.
</t>
<section title="Edge Node TSN Procedures" anchor="tom_tsn_proc">
<t>
The Time-Sensitive Networking (TSN) Task Group of the IEEE 802.1
Working Group have defined (and are defining) a number of amendments
to <xref target="IEEE8021Q">IEEE 802.1Q</xref> that provide zero
congestion loss and bounded latency in bridged networks.
<xref target="IEEE8021CB">IEEE 802.1CB</xref> defines packet
replication and elimination functions for a TSN network.
</t>
<t>
The implementation of TSN entity (i.e., TSN packet processing
functions) MUST be compliant with the relevant IEEE 802.1
standards.
</t>
<t>
TSN specific functions are executed on the data received by
the DetNet Edge Node from the connected CE before forwarded to
connected CE(s) or presentation to the DetNet Service Proxy function for
transmission across the DetNet domain, or on the data received from
a DetNet PW by a PE before it is output on the Attachment Circuit(s) (AC).
</t>
<t>
TSN packet processing function(s) of Edge Nodes (T-PE) are belonging to the
native service processing (NSP) <xref target="RFC3985"/>
block. This is similar to other functionalities being defined by standard
bodies other than the IETF (for example in case of Ethernet: stripping,
overwriting or adding VLAN tags, etc.). Depending on the TSN role of
the Edge Node in the end-to-end TSN service selected TSN functions
are supported.
</t>
<t>
When a PE receives a packet from a CE, on a given AC with DetNet service,
it MUST first check via Stream Identification
(see Clause 6. of <xref target="IEEE8021CB">IEEE 802.1CB</xref> and
<xref target="IEEEP8021CBdb">IEEE P802.1CBdb</xref>)
whether the packet belongs
to a configured TSN Stream (i.e., App-flow from DetNet perspective).
If no Stream ID is matched and no other (VPN) service is configured
for the AC then packet MUST be dropped. If there is a matching TSN
Stream then the Stream-ID specific TSN functions MUST be executed
(e.g., ingress policing, header field manipulation in case
of active Stream Identification, FRER, etc.). Source MAC lookup
MAY also be used for local MAC address learning.
</t>
<t>
If the PE decides to forward the packet, the packet MUST be forwarded
according to the TSN Stream specific configuration to connected CE(s)
(in case of local bridging) and/or to the DetNet Service Proxy
(in case of forwarding to remote CE(s) required). If there are no
TSN Stream specific forwarding configurations the PE MUST flood
the packet to other locally attached CE(s) and to the DetNet Service
Proxy. If the administrative policy on the PE does not allow
flooding the PE MUST drop the packet.
</t>
<t>
When a TSN entity of the PE receives a packet from the DetNet
Service Proxy, it MUST first check via Stream Identification
(see Clause 6. of <xref target="IEEE8021CB">IEEE 802.1CB</xref> and
<xref target="IEEEP8021CBdb">IEEE P802.1CBdb</xref>) whether
the packet belongs to a configured TSN Stream. If no Stream ID is
matched then packet MUST be dropped. If there is a matching TSN
Stream then the Stream ID specific TSN functions MUST be executed
(e.g., header field manipulation in case of active Stream
Identification, FRER, etc.). Source MAC lookup MAY also be used for
local MAC address learning.
</t>
<t>
If the PE decides to forward the packet, the packet MUST be forwarded
according to the TSN Stream specific configuration to connected CE(s).
If there are no TSN Stream specific forwarding configurations the
PE MUST flood the packet to locally attached CE(s). If the
administrative policy on the PE does not allow flooding the PE MUST
drop the packet.
</t>
<t>
Implementations of this document SHALL use management and
control information to ensure TSN specific functions of the Edge Node
according to the expectations of the connected TSN network.
</t>
</section>
<section title="Edge Node DetNet Service Proxy Procedures" anchor="tom_svc_prx_proc">
<t>
The Service Proxy
function maps between App-flows and DetNet flows.
The DetNet Edge Node TSN entity MUST support the TSN Stream
identification functions and the related managed objects as
defined in Clause 6. and Clause 9. of
<xref target="IEEE8021CB">IEEE 802.1CB</xref> and
<xref target="IEEEP8021CBdb">IEEE P802.1CBdb</xref> to
recognize the App-flow related packets. The Service Proxy
presents TSN Streams as an App-flow to a DetNet Flow.
</t>
<t>
When a DetNet Service Proxy receives a packet from the TSN Entity
it MUST check whether such an App-flow is present in its mapping table.
If present it associates the internal DetNet flow-ID to the packet and
MUST forward it to the DetNet Service and Forwarding sub-layers. If
no matching statement is present it MUST drop the packet.
</t>
<t>
When a DetNet Service Proxy receives a packet from the DetNet Service
and Forwarding sub-layers it MUST be forwarded to the Edge Node
TSN Entity.
</t>
<t>
Implementations of this document SHALL use management and
control information to map a TSN Stream to a DetNet flow.
N:1 mapping (aggregating multiple TSN Streams in a single
DetNet flow) 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.
</t>
<t>
Due to the (intentional) similarities of the DetNet PREOF and
TSN FRER functions service protection function interworking is
possible between the TSN and the DetNet domains. Such service
protection interworking scenarios MAY require to copy sequence
number fields from TSN (L2) to PW (MPLS) encapsulation.
However, such interworking is out-of-scope in this document and
left for further study.
</t>
<t>
A MPLS DetNet flow is configured to carry any number of
TSN flows. The DetNet flow specific bandwidth profile SHOULD
match the required bandwidth of the App-flow aggregate.
</t>
</section>
<section title="Edge Node DetNet Service and Forwarding Sub-Layer Procedures" anchor="tom_dn_sub_proc">
<t>
In the design of <xref target="I-D.ietf-detnet-mpls"/> an MPLS service
label (the S-Label), similar to a pseudowire (PW) label
<xref target="RFC3985"/>, is used to identify both the DetNet flow
identity and the payload MPLS payload type. The DetNet sequence
number is carried in the DetNet Control word (d-CW) which carries the
Data/OAM discriminator as well. In
<xref target="I-D.ietf-detnet-mpls"/> two sequence number sizes
are supported: a 16 bit sequence number and a 28 bit sequence number.
</t>
<t>
PREOF functions and the provided service recovery is available
only within the DetNet domain as the DetNet flow-ID and the DetNet
sequence number are not valid outside the DetNet network. MPLS
(DetNet) Edge node terminates all related information elements
encoded in the MPLS labels.
</t>
<t>
The LSP used to forward the DetNet packet may be of any type (MPLS-LDP,
MPLS-TE, MPLS-TP <xref target="RFC5921"/>, or MPLS-SR
<xref target="RFC8660"/>). The LSP
(F-Label) label and/or the S-Label may be used to indicate the queue
processing as well as the forwarding parameters.
</t>
<t>
When a PE receives a packet from the Service Proxy function it MUST
add to the packet the DetNet flow-ID specific S-label and create a
d-CW. The PE MUST forward the packet according to the configured
DetNet Service and Forwarding sub-layer rules to other PE nodes.
</t>
<t>
When a PE receives an MPLS packet from a remote PE, then, after
processing the MPLS label stack, if the top MPLS label ends up being
a DetNet S-label that was advertised by this node, then the PE
MUST forward the packet according to the configured DetNet Service and
Forwarding sub-layer rules to other PE nodes or via the Detnet Service
Proxy function towards locally connected CE(s).
</t>
<t>
For further details on DetNet Service and Forwarding sub-layers
see <xref target="I-D.ietf-detnet-mpls"/>.
</t>
</section>
</section> <!-- End of Procedures Section -->
<!-- ========================================================== -->
<!-- Management and Control Plane Considerations -->
<!-- ========================================================== -->
<section title="Controller Plane (Management and Control) Considerations" anchor="cp_considerations">
<t>
TSN Stream(s) to DetNet flow mapping related information are
required only for the service proxy function of MPLS (DetNet) Edge nodes.
From the Data Plane perspective there is no practical difference
based on the origin of flow mapping related information (management
plane or control plane).
</t>
<t>
The following summarizes the set of information that is needed to
configure TSN over DetNet MPLS:
<list style="symbols">
<t>TSN related configuration information according to the
TSN role of the DetNet MPLS node, as per
<xref target="IEEE8021Q"/>, <xref target="IEEE8021CB"/> and
<xref target="IEEEP8021CBdb"/>. </t>
<t>DetNet MPLS related configuration information according to the
DetNet role of the DetNet MPLS node, as per
<xref target="I-D.ietf-detnet-mpls"/>. </t>
<t>App-Flow identification information to map received TSN
Stream(s) to the DetNet flow. Parameters fo TSN stream
identification are defined in <xref target="IEEE8021CB"/> and
<xref target="IEEEP8021CBdb"/>.
Note, that managed objects for TSN Stream identification can be
found in <xref target="IEEEP8021CBcv"/>. </t>
</list>
This information MUST be provisioned per DetNet flow.
</t>
<t>
MPLS DetNet Edge nodes are member of both the DetNet domain and the
connected TSN network. From the TSN network perspective the MPLS
(DetNet) Edge node has a "TSN relay node" 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.
</t>
<t>
Note that, as the DetNet network is just a portion of the end to end TSN
path (i.e., single hop from Ethernet perspective), some parameters
(e.g., delay) may differ significantly. Since there is no interworking
function the bandwidth of DetNet network is assumed to be set large enough to
handle all TSN Flows it will support. At the egress of the Detnet Domain the MPLS
headers are stripped and the TSN flow continues on as a normal TSN
flow.
</t>
<t>
In order to use a DetNet network to interconnect TSN segments,
TSN specific information must be converted to DetNet domain
specific ones. TSN Stream ID(s) and stream(s) related
parameters/requirements must be converted to a DetNet flow-ID and
flow related parameters/requirements.
</t>
<t>
In some case it may be challenging to determine some egress node
related information. For example, it may be not trivial to
locate the egress point/interface of a TSN Streams with a
multicast destination MAC address. Such scenarios may
require interaction between control and management plane
functions and between DetNet and TSN domains.
</t>
<t>
Mapping between DetNet flow identifiers and TSN Stream
identifiers, if not provided explicitly, can be done by the service
proxy function of an MPLS (DetNet) Edge node locally based on information
provided for configuration of the TSN Stream identification functions
(e.g., Mask-and-Match Stream identification).
</t>
<t>
Triggering the setup/modification of a DetNet flow in the
DetNet network is an example where management and/or
control plane interactions are required between the DetNet
and the TSN network.
</t>
<t>
Configuration of TSN specific functions (e.g., FRER)
inside the TSN network is a TSN domain specific decision
and may not be visible in the DetNet domain. Service protection
interworking scenarios are left for further study.
</t>
</section> <!-- End of Management and Control Plane COnsiderations -->
<section title="Security Considerations">
<t>
Security considerations for DetNet are described in detail in <xref
target="I-D.ietf-detnet-security"/>. General security
considerations are described in <xref
target="RFC8655"/>.
</t>
<t>
DetNet MPLS data plane specific considerations are summarized and
described in <xref target="I-D.ietf-detnet-mpls"/> including any
application flow types. This document focuses on the scenario where TSN
Streams are the application flows for DetNet and it is already covered
by those DetNet MPLS data plane security considerations.
</t>
</section>
<section anchor="iana" title="IANA Considerations">
<t>
This document makes no IANA requests.
</t>
</section>
<section anchor="acks" title="Acknowledgements">
<t>
The authors wish to thank Norman Finn, Lou Berger, Craig Gunther,
Christophe Mangin and Jouni Korhonen for their various contributions
to this work.
</t>
</section>
</middle>
<back>
<references title="Normative References">
&rfc2119;
<?rfc include="reference.RFC.3031"?>
<?rfc include="reference.RFC.8174"?>
<?rfc include="reference.I-D.ietf-detnet-mpls"?>
</references>
<references title="Informative References">
&rfc3985;
&rfc5921;
&rfc8660;
<?rfc include="reference.RFC.8655"?>
<?rfc include="reference.I-D.ietf-detnet-data-plane-framework"?>
<?rfc include="reference.I-D.ietf-detnet-security"?>
<?rfc include="reference.RFC.4301"?>
<reference anchor="IEEE802.1AE-2018"
target="https://ieeexplore.ieee.org/document/8585421">
<front>
<title>IEEE Std 802.1AE-2018 MAC Security (MACsec)</title>
<author>
<organization>IEEE Standards Association</organization>
</author>
<date year="2018" />
</front>
</reference>
<reference anchor="IEEE8021Q"
target="http://standards.ieee.org/about/get/">
<front>
<title>Standard for Local and metropolitan area networks--Bridges and Bridged Networks (IEEE Std 802.1Q-2014)</title>
<author>
<organization>IEEE 802.1</organization>
</author>
<date year="2014"/>
</front>
<format type="PDF" target="http://standards.ieee.org/about/get/"/>
</reference>
<reference anchor="IEEE8021CB"
target="http://www.ieee802.org/1/files/private/cb-drafts/d2/802-1CB-d2-1.pdf">
<front>
<title>Draft Standard for Local and metropolitan area networks - Seamless Redundancy</title>
<author initials="N. F." surname="Finn" fullname="Norman Finn">
<organization>IEEE 802.1</organization>
</author>
<date month="December" year="2015"/>
</front>
<seriesInfo name="IEEE P802.1CB /D2.1" value="P802.1CB"/>
<format type="PDF" target="http://www.ieee802.org/1/files/private/cb-drafts/d2/802-1CB-d2-1.pdf"/>
</reference>
<reference anchor="IEEEP8021CBdb"
target="http://www.ieee802.org/1/files/private/cb-drafts/d2/802-1CB-d2-1.pdf">
<front>
<title>Extended Stream identification functions</title>
<author initials="C. M." surname="Mangin" fullname="Christophe Mangin">
<organization>IEEE 802.1</organization>
</author>
<date month="August" year="2019"/>
</front>
<seriesInfo name="IEEE P802.1CBdb /D0.2" value="P802.1CBdb"/>
<format type="PDF" target="http://www.ieee802.org/1/files/private/cb-drafts/d2/802-1CB-d2-1.pdf"/>
</reference>
<reference anchor="IEEEP8021CBcv"
target="http://www.ieee802.org/1/files/private/cv-drafts/d0/802-1CBcv-d0-3.pdf">
<front>
<title>FRER YANG Data Model and Management Information Base Module</title>
<author initials="S." surname="Kehrer" fullname="Stephan Kehrer">
<organization>IEEE 802.1</organization>
</author>
<date month="May" year="2020"/>
</front>
<seriesInfo name="IEEE P802.1CBcv /D0.3" value="P802.1CBcv"/>
<format type="PDF" target="http://www.ieee802.org/1/files/private/cv-drafts/d0/802-1CBcv-d0-3.pdf"/>
</reference>
</references>
</back>
</rfc>