Internet DRAFT - draft-geng-detnet-dp-sol-srv6
draft-geng-detnet-dp-sol-srv6
Network Working Group X. Geng
Internet-Draft M. Chen
Intended status: Experimental Huawei
Expires: September 13, 2020 Y. Zhu
China Telecom
March 12, 2020
DetNet SRv6 Data Plane Encapsulation
draft-geng-detnet-dp-sol-srv6-02
Abstract
This document specifies Deterministic Networking data plane operation
for SRv6 encapsulated user data.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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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This Internet-Draft will expire on September 13, 2020.
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publication of this document. Please review these documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology and Conventions . . . . . . . . . . . . . . . . . 3
2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Conventions . . . . . . . . . . . . . . . . . . . . . . . 4
3. SRv6 DetNet Data Plane Overview . . . . . . . . . . . . . . . 4
3.1. SRv6 DetNet Data Plane Layers . . . . . . . . . . . . . . 5
3.2. SRv6 DetNet Data Plane Scenarios . . . . . . . . . . . . 5
4. SRv6 DetNet Data Plane Solution Considerations . . . . . . . 7
5. SRv6 DetNet Data Plane Solution for Service Sub-layer . . . . 8
5.1. TLV Based SRv6 Data Plane Solution . . . . . . . . . . . 9
5.1.1. Encapsulation . . . . . . . . . . . . . . . . . . . . 9
5.1.2. Replication SID and Elimination for DetNet . . . . . 11
5.2. SID Based SRv6 Data Plane Solution . . . . . . . . . . . 13
5.2.1. Encapsulation . . . . . . . . . . . . . . . . . . . . 13
5.2.2. Functions . . . . . . . . . . . . . . . . . . . . . . 14
5.3. DetNet SID Based SRv6 Data Plane Solution . . . . . . . . 15
5.3.1. Encapulation . . . . . . . . . . . . . . . . . . . . 15
5.3.2. Functions . . . . . . . . . . . . . . . . . . . . . . 15
6. SRv6 DetNet Data Plane Solution for Transport Sub-layer . . . 16
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
10. Normative References . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Deterministic Networking (DetNet), as described in
[I-D.ietf-detnet-architecture] provides a capability to carry
specified data flows with extremely low data loss rates and bounded
latency within a network domain. DetNet is enabled by a group of
technologies, such as resource allocation, service protection and
explicit routes.
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 the
Segment Routing Extension Header (SRH,
[I-D.ietf-6man-segment-routing-header]). A segment in segment
routing terminology is not limited to a routing/forwarding function.
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A segment can be associated to an arbitrary processing of the packet
in the node identified by the segment. In other words, an SRv6
Segment can indicate functions that are executed locally in the node
where they are defined. SRv6 network Programming
[I-D.filsfils-spring-srv6-network-programming] describe the different
segments and functions associated to them.
This document describes how to implement DetNet in an SRv6 enabled
domain, including :
o Source routing, which steers the DetNet flows through the network
according to an explicit path with allocated resources;
o Network programming, which applies instructions (functions) to
packets in some special nodes (or even all the nodes) along the path
in order to guarantee, e.g., service protection and congestion
protection.
DetNet SRv6 encapsulation and new SRv6 functions
([I-D.filsfils-spring-srv6-network-programming]) for DetNet are
defined in this document. Control plane and OAM are not in the scope
of this document.
Control plane and OAM are not in the scope of this document.
2. Terminology and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2.1. Terminology
Terminologies for DetNet go along with the definition in
[I-D.ietf-detnet-architecture] and [RFC8402]. Other terminologies
are defined as follows:
o NH: The IPv6 next-header field.
o SID: A Segment Identifier ([RFC8402]).
o SRH: The Segment Routing Header
([I-D.ietf-6man-segment-routing-header]).
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2.2. Conventions
Conventions in the document are defined as follows:
o NH=SRH means that NH is 43 with routing type 4 which is (as
defined in [I-D.ietf-6man-segment-routing-header], the values
representing the SRH.
o A SID list is represented as <S1, S2, S3> where S1 is the first
SID to visit, S2 is the second SID to visit and S3 is the last SID
to visit along the SR path.
o SRH[SL] represents the SID pointed by the SL field in the first
SRH. In our example, SRH[2] represents S1, SRH[1] represents S2
and SRH[0] represents S3. It has to be noted that
[I-D.ietf-6man-segment-routing-header] defines the segment list
encoding in the reverse order of the path. A path represented by
<S1,S2,S3>, will be encoded in the SRH as follows:
SegmentList[0]=S3
SegmentList[1]=S2
SegmentList[2]=S1
The reverse encoding has been defined in order to optimise the
processing time of the segment list. See [draft-ietf-6man-
segment-routing-header] for more details.
o (SA,DA) (S3, S2, S1; SL) represents an IPv6 packet with:
IPv6 header with source and destination addresses SA and DA
respectively, and next-header set to SRH (i.e.: 43 with type 4)
, with a list of segments(SIDs) <S1, S2, S3> with SegmentsLeft
= SL
The payload of the packet is not represented
(S3, S2, S1; SL) represents the same SID list as <S1, S2, S3>,
but encoded in the SRH format where the rightmost SID in the
SRH is the first SID and the leftmost SID in the SRH is the
last SID
3. SRv6 DetNet Data Plane Overview
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3.1. SRv6 DetNet Data Plane Layers
[I-D.ietf-detnet-architecture]decomposes the DetNet data plane into
two sub-layers: service sub-layer and transport sub-layer. Different
from DetNet MPLS data plane solution, which uses DetNet Control
Word(d-CW) and S-Label to support service sub-layer and uses T-Label
to support transport sub-layer, no explicit sub-layer division exists
in SRv6 data plane. A classical SRv6 DetNet data plane solution is
showed in the picture below:
+-------------------+
| Outer Ipv6 Header |
+-------------------+
| SRH |
+-------------------+ +-------------------+
| Ipv6 Header | ----> | Ipv6 Header |
+-------------------+ +-------------------+
The outer IPv6 Header 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.
3.2. SRv6 DetNet Data Plane Scenarios
| |
----IPv6--->|<---------------SRv6 DetNet------------->|<----IPv6---
| |
| +------+T2+----+ |
+---+ +---+ +-+-+ +-+-+ +---+ +---+
| E1+----| In|--+T1+--+R1 | |R2 |--+T4+--| Eg+----+ E2|
+---+ +---+ +-+-+ +-+-+ +---+ +---+
+-----+T3+-----+
The figure above shows that an IPv6 flow is sent out from the end
station E1. The packet of the flow is encapsulated in an outer
IPv6+SRH header as a DetNet SRv6 packet in the Ingress(In) and
transported through an SRv6 DetNet domain. In the Egress(Eg), the
outer IPv6 header+SRH of the packet is popped, and the packet is sent
to the destination E2.
The figure above shows that an IPv6 flow is sent our from the end
station: E1. The packet of the flow is encapsulated as a DetNet SRv6
packet in the Ingress(In) and transported through an SRv6 DetNet
domain. In the Egress(Eg), the upper IPv6 header with SRH of the
packet is popped, and the packet is transmitted to the
destination(E2).
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The DetNet packet processing is as follows:
Ingress:
Inserts the SRv6 Policy that will steer the packet from Ingress to
the destination
The methods and mechanisms used for defining, instantiating and
applying the policy are outside of this document. An example of
policies are described in [I-D.ietf-spring-segment-routing-policy]
Flow Identification and Sequence Number are carried in the SRH
optionally.
Relay Node 1(Replication Node):
Replicates the payload and IPv6 Header with the SRH. This is a
new function in the context of SRv6 Network Programming which will
associate a given SID to a replication instruction in the node
originating and advertising the SID. The replication instruction
includes:
* The removal of the existing IPv6+SRH header
* The encapsulation into a new outer IPv6+SRH header. Each
packet (the original and the duplicated) are encapsulated into
respectively new outer IPv6+SRH headers.
Binding two different SRv6 Policies respectively to the original
packet and the replicated packet, which can steer the packets from
Relay Node 1 to Relay Node 2 through two tunnels.
If Flow Identification and Sequence Number are not carried in the
SRH in the ingress, add it them in the SRH.
Relay Node 2(Elimination Node):
Eliminates the redundant packets.
Binds a new SRv6 Policy to the survival packet, which steers the
packet from Relay Node 2 to Egress.
Egress:
Decapsulates the outer Ipv6 header.
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Sends the inter packet to the End Station 2.
The DetNet packet encapsulation is illustrated here below. It has to
be noted that, in the example below, the R2 address is a SRH SID
associated to a TBD function related to the packet replication the
node R1 has to perform. The same (or reverse) apply to node R2 which
is in charge of the discard of the duplicated packet. Here also a
new function will have a new SID allocated to it and representing the
delete of the duplication in R2.
End Station1 output packet: (E1,E2)
Ingress output packet: (In, T1)(R1,T1, SL=2)(E1,E2)
Transit Node1 output packet: (In, R1)(R1,T1,SL=1)(E1,E2)
Relay Node1 output packets : (R1,T2)(R2,T2,SL=2)(E1,E2),
(R1,T3)(R2,T3,SL=2)(E1,E2)
Transit Node2 output packet: (R1, R2)(R2,T2,SL=1)(E1,E2)
Transit Node3 output packet: (R1, R2)(R2,T3,SL=1)(E1,E2)
Relay Node2 output packet: (R2, T4)(Eg,T4,SL=2)(E1,E2)
Transit Node4 output packet: (R2, Eg)(Eg,T4,SL=1)(E1,E2)
Egress out : (E1,E2)
4. SRv6 DetNet Data Plane Solution Considerations
To carry DetNet over SRv6, the following elements are required:
1. A method of identifying the SRv6 payload type;
2. A suitable explicit path to deliver the DetNet flow ;
3. A method of indicating packet processing, such as PREOF(Packet
Replication, Elimination and Ordering as defined in
[I-D.ietf-detnet-architecture]);
4. A method of identifying the DetNet flow;
5. A method of carrying DetNet sequence number;
6. A method of carrying queuing and forwarding indication to do
congestion protection;
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In this design, DetNet flows are encapsulated in an outer IPv6+SRH
header at the Ingress Node. The SR policy identified in the SRH
steers the DetNet flow along a selected path. The explicit path
followed by a DetNet flow, which protect it from temporary
interruptions caused by the convergence of routing, is encoded within
the SID list of the SR policy. The network device inside the DetNet
domain forwards the packet according to IPv6 Destination Address(DA),
and the IPv6 DA is updated with the SID List according to SRv6
forwarding procedures defined in
[I-D.ietf-6man-segment-routing-header] and
[I-D.filsfils-spring-srv6-network-programming]
With SRv6 network programming, the SID list can also give instruments
representing a function to be called at the node in the DetNet
domain. Therefore DetNet specific functions defined in
[I-D.ietf-detnet-architecture], corresponding to local packet
processing in the network, can also be implemented by SRv6. New
functions associated with SIDs for DetNet are defined in this
document.
This document describes how DetNet flows are encapsulated/identified,
and how functions of Packet Replication/Elimination/Ordering are
implemented in an SRv6 domain. Congestion protection is also in the
scope of this document.
Editor: This version only covers the functions of service protection
and the congestion protection considerations will be added in the
following versions.
5. SRv6 DetNet Data Plane Solution for Service Sub-layer
This section defines options of SRv6 data plane solution to support
DetNet Service Sub-layer.
SRH is as follows, which defined in
[I-D.ietf-6man-segment-routing-header]
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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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Segment List[0] |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Segment List[n] |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional TLVs |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The SRH specification allows the use of optional TLVs.
Each SRv6 Segment in the segment list is a 128-bit value. SID is
used as a shorter reference for "SRv6 Segment Identifier" or "SRV6
Segment". SRv6 SID can also be represented as LOC:FUNCT, where:
LOC, means "LOCATION" and defines the node associated with the SID
(i.e.: represented by the SID).
FUNCT, means "FUNCTION", and identifies the processing that the
node specified in LOC applies to the packet. See
[I-D.filsfils-spring-srv6-network-programming] for details on SRV6
Network Programming.
as defined in [I-D.filsfils-spring-srv6-network-programming].
5.1. TLV Based SRv6 Data Plane Solution
5.1.1. Encapsulation
Two new TLVs are defined to support DetNet service protection.
DetNet Flow Identification TLV is used to uniquely identify a DetNet
flow in an SRv6 DetNet node. DetNet sequence number is used to
discriminate packets in the same DetNet flow. They are defined as
follows:
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Option 1: separated TLVs for flow identification and sequence
number
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 | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | Flow Identification |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
o Type: 8bits, to be assigned by IANA.
o Length: 8 octets.
o RESERVED: 28 bits, MUST be 0 on transmission and ignored on
receipt.
o Flow Identification: 20 bits, which is used for identifying DetNet
flow.
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 | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|RESERVD| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
o Type: 8 bits, to be assigned by IANA.
o Length: 8.
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.
Option 2: unified TLV for flow identification and sequence number
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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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
o Type: 8 bits, to be assigned by IANA.
o Length: 12.
o Flow Identification: 20 bits, which is used for identifying DetNet
flow.
o Sequence Number: 28 bits, which is used for indicating sequence
number of a DetNet flow.
o RESERVED: 32 bits. MUST be 0 on transmission and ignored on
receipt.
5.1.2. Replication SID and Elimination for DetNet
New SIDs, replication SID and elimination SID, are defined as
follows:
5.1.2.1. Replication SID
Redundancy SID is a variation of binding SID defined in
[I-D.ietf-spring-segment-routing-policy] Redundancy SID indicates the
following operations:
o Steering the packet into the corresponding redundancy policy
o Packet replication based on the redundancy policy, e.g., the
number of replication copies
o Encapsulate the packet with necessary meta data (e.g., flow
identification, sequence number) if it is not included in the
original packet
When N receives a packet whose IPv6 DA is S and S is a Replication
SID, N could do:
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1. IF NH=SRH & SL>0 THEN
2. extract the DetNet TLV values from the SRH
3. 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 TLVs into
SRH-1 and SRH-2.
4. remove the incoming outer IPv6+SRH header.
5. create a duplication of the incoming packet.
6. encapsulate the original packet into the first outer IPv6+SRH
header: (IPv6-SRH-1) (original packet)
7. encapsulate the duplicate packet into the second outer IPv6+SRH
header: (IPv6-SRH-2) (duplicate packet)
8. set the IPv6 SA as the local address of this node.
9. set the IPv6 DA of IPv6-SRH-1 to the first segment of the SRv6
Policy in of SRH-1 segment list.
10. set the IPv6 DA of IPv6-SRH-2 to the first segment of the SRv6
Policy in of SRH-2 segment list.
11. ELSE
12. drop the packet
5.1.2.2. Elimination SID
Elimination SID indicates the following operations:
o Packet elimination: forward the first received packets and
eliminate the redundant packets.
o Packet ordering(optional): reorder the packets if the packet
arrives out of order
When N receives a packet whose IPv6 DA is S and S is a Elimination
SID, N could do:
1. IF NH=SRH & SL>0 & "the packet is not a redundant packet" THEN
2. do not decrement SL nor update the IPv6 DA with SRH[SL]
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3. extract the value of DetNet TLVs from the SRH
4. create a new outer IPv6+SRH header
5. insert the policy-instructed segment lists in the newly created
SRH and add the retrieved DetNet TLVs in the newly created SRH
6. remove the incoming outer IPv6+SRH header.
7. set the IPv6 DA to the first segment of the SRv6 Policy in the
newly created SRH
8. ELSE
9. drop the packet
5.2. SID Based SRv6 Data Plane Solution
5.2.1. Encapsulation
SRv6 SID can be represented as LOC:FUNCT:ARG::, where:
LOC, means "LOCATION" and defines the node associated with the SID
(i.e.: represented by the SID).
FUNCT, means "FUNCTION", and identifies the processing that the node
specified in LOC applies to the packet.
ARG, means "ARGUMENTS" and provides the additional arguments for the
function. New SID functions for DetNet is defined in section 5.2.2.
See [I-D.filsfils-spring-srv6-network-programming] for details on
SRV6 Network Programming. The SRH for DetNet in the outer IPv6
header is illustrated as follows
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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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Location & Function |
| (Segment List[0] for relay node or edge node) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Location & Function | Flow Identification |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Flow ID| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Segment List[n] |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional TLVS |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
where:
o LOCATION&FUNCTION: the 80 most significant bits that are used for
routing the packet towards the LOCATION (as defined in
[I-D.filsfils-spring-srv6-network-programming]);
o FLOW IDENTIFICATION: 20 bits, in the DetNet TLVs in the SRH, used
for DetNet flow identification in the DetNet relay node;
o SEQUENCE NUMBER : 28 bits, in the DetNet TLVs, used for dis crime
packets in the same DetNet flow;
5.2.2. Functions
New SID functions are defined as follows:
5.2.2.1. End. B.Replication: Packet Replication Function
The function is similar as that has been defined in section 5.1.2.1.
The only difference is that instead of retrieving the TLV values,
this function retrieves the argument.
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5.2.2.2. End. B. Elimination: Packet Elimination Function
The function is similar as that has been defined in section 5.1.2.2.
The only difference is that instead of retrieving the TLV values,
this function retrieves the argument.
5.3. DetNet SID Based SRv6 Data Plane Solution
5.3.1. Encapulation
A non-forwarding DetNet SID is defined to carry Flow Identification
and Sequence Number.
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Location & Function |
| (Segment List[0] for relay node or edge node) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Segment List[n] |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| DetNet SID |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Optional TLVs |
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
5.3.2. Functions
TBD
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6. SRv6 DetNet Data Plane Solution for Transport Sub-layer
TBD
7. IANA Considerations
TBD
8. Security Considerations
TBD
9. Acknowledgements
Thank you for valuable comments from James Guichard and Andrew Mails.
10. Normative References
[I-D.filsfils-spring-srv6-network-programming]
Filsfils, C., Camarillo, P., Leddy, J.,
daniel.voyer@bell.ca, d., Matsushima, S., and Z. Li, "SRv6
Network Programming", draft-filsfils-spring-srv6-network-
programming-07 (work in progress), February 2019.
[I-D.ietf-6man-segment-routing-header]
Filsfils, C., Dukes, D., Previdi, S., Leddy, J.,
Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
(SRH)", draft-ietf-6man-segment-routing-header-26 (work in
progress), October 2019.
[I-D.ietf-detnet-architecture]
Finn, N., Thubert, P., Varga, B., and J. Farkas,
"Deterministic Networking Architecture", draft-ietf-
detnet-architecture-13 (work in progress), May 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-spring-segment-routing-policy]
Filsfils, C., Sivabalan, S., Voyer, D., Bogdanov, A., and
P. Mattes, "Segment Routing Policy Architecture", draft-
ietf-spring-segment-routing-policy-06 (work in progress),
December 2019.
Geng, et al. Expires September 13, 2020 [Page 16]
Internet-Draft Abbreviated-Title March 2020
[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>.
[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>.
Authors' Addresses
Xuesong Geng
Huawei
Email: gengxuesong@huawei.com
Mach(Guoyi) Chen
Huawei
Email: mach.chen@huawei.com
Yongqing Zhu
China Telecom
Email: zhuyq@gsta.com
Geng, et al. Expires September 13, 2020 [Page 17]
