draft-ietf-idr-sr-policy-path-segment-00.txt   draft-ietf-idr-sr-policy-path-segment-01.txt 
Interdomain Routing Working Group C. Li Interdomain Routing Working Group C. Li
Internet-Draft Z. Li Internet-Draft Z. Li
Intended status: Standards Track Huawei Technologies Intended status: Standards Track Huawei Technologies
Expires: May 1, 2020 H. Chen Expires: February 12, 2021 H. Chen
China Telecom China Telecom
W. Cheng W. Cheng
China Mobile China Mobile
K. Talaulikar K. Talaulikar
Cisco Systems Cisco Systems
October 29, 2019 August 11, 2020
SR Policy Extensions for Path Segment and Bidirectional Path SR Policy Extensions for Path Segment and Bidirectional Path
draft-ietf-idr-sr-policy-path-segment-00 draft-ietf-idr-sr-policy-path-segment-01
Abstract Abstract
A Segment Routing (SR) policy is a set of candidate SR paths A Segment Routing (SR) policy is a set of candidate SR paths
consisting of one or more segment lists with necessary path consisting of one or more segment lists with necessary path
attributes. For each SR path, it may also have its own path attributes. For each SR path, it may also have its own path
attributes, and Path Segment is one of them. A Path Segment is attributes, and Path Segment is one of them. A Path Segment is
defined to identify an SR path, which can be used for performance defined to identify an SR path, which can be used for performance
measurement, path correlation, and end-2-end path protection. Path measurement, path correlation, and end-2-end path protection. Path
Segment can be also used to correlate two unidirctional SR paths into Segment can be also used to correlate two unidirectional SR paths
a bidirectional SR path which is required in some scenarios, for into a bidirectional SR path which is required in some scenarios, for
example, mobile backhaul transport network. example, mobile backhaul transport network.
This document defines extensions to BGP to distribute SR policies This document defines extensions to BGP to distribute SR policies
carrying Path Segment and bidirectional path information. carrying Path Segment and bidirectional path information.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
skipping to change at page 2, line 7 skipping to change at page 2, line 7
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This Internet-Draft will expire on May 1, 2020. This Internet-Draft will expire on February 12, 2021.
Copyright Notice Copyright Notice
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document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. Path Segment in SR Policy . . . . . . . . . . . . . . . . . . 3 3. Path Segment in SR Policy . . . . . . . . . . . . . . . . . . 3
3.1. SR Path Segment Sub-TLV . . . . . . . . . . . . . . . . . 4 3.1. SR Path Segment Sub-TLV . . . . . . . . . . . . . . . . . 5
4. SR Policy for Bidirectional Path . . . . . . . . . . . . . . 6 4. SR Policy for Bidirectional Path . . . . . . . . . . . . . . 6
4.1. SR Bidirectional Path Sub-TLV . . . . . . . . . . . . . . 6 4.1. Reverse Path Segment List Sub-TLV . . . . . . . . . . . . 7
4.2. SR Reverse Path Segment List Sub-TLV . . . . . . . . . . 7
5. Operations . . . . . . . . . . . . . . . . . . . . . . . . . 8 5. Operations . . . . . . . . . . . . . . . . . . . . . . . . . 8
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
6.1. Existing Registry: BGP Tunnel Encapsulation Attribute 6.1. Existing Registry: BGP Tunnel Encapsulation Attribute
sub-TLVs . . . . . . . . . . . . . . . . . . . . . . . . 8 sub-TLVs . . . . . . . . . . . . . . . . . . . . . . . . 9
7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 9 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 9
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
10.1. Normative References . . . . . . . . . . . . . . . . . . 10 10.1. Normative References . . . . . . . . . . . . . . . . . . 10
10.2. Informative References . . . . . . . . . . . . . . . . . 11 10.2. Informative References . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
Segment routing (SR) [RFC8402] is a source routing paradigm that Segment routing (SR) [RFC8402] is a source routing paradigm that
explicitly indicates the forwarding path for packets at the ingress explicitly indicates the forwarding path for packets at the ingress
node. The ingress node steers packets into a specific path according node. The ingress node steers packets into a specific path according
to the Segment Routing Policy ( SR Policy) as defined in to the Segment Routing Policy ( SR Policy) as defined in
[I-D.ietf-spring-segment-routing-policy]. For distributing SR [I-D.ietf-spring-segment-routing-policy]. For distributing SR
policies to the headend, [I-D.ietf-idr-segment-routing-te-policy] policies to the headend, [I-D.ietf-idr-segment-routing-te-policy]
skipping to change at page 3, line 22 skipping to change at page 3, line 22
path identification information for each Segment List in the SR path identification information for each Segment List in the SR
Policies defined in [I-D.ietf-spring-segment-routing-policy]. Also, Policies defined in [I-D.ietf-spring-segment-routing-policy]. Also,
the SR Policies defined in [I-D.ietf-spring-segment-routing-policy] the SR Policies defined in [I-D.ietf-spring-segment-routing-policy]
only supports unidirectional SR paths. only supports unidirectional SR paths.
Therefore, this document defines the extension to SR policies that Therefore, this document defines the extension to SR policies that
carry Path Segment in the Segment List and support bidirectional carry Path Segment in the Segment List and support bidirectional
path. The Path Segment can be a Path Segment in SR-MPLS path. The Path Segment can be a Path Segment in SR-MPLS
[I-D.ietf-spring-mpls-path-segment] , or other IDs that can identify [I-D.ietf-spring-mpls-path-segment] , or other IDs that can identify
a path. Also, this document defines extensions to BGP to distribute a path. Also, this document defines extensions to BGP to distribute
SR policies carriying Path Segment and bidirectional path SR policies carrying Path Segment and bidirectional path information.
information.
2. Terminology 2. Terminology
This memo makes use of the terms defined in [RFC8402] and This memo makes use of the terms defined in [RFC8402] and
[I-D.ietf-idr-segment-routing-te-policy]. [I-D.ietf-idr-segment-routing-te-policy].
2.1. 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.
3. Path Segment in SR Policy 3. Path Segment in SR Policy
As defined in [I-D.ietf-idr-segment-routing-te-policy] , the SR As defined in [I-D.ietf-idr-segment-routing-te-policy] , the SR
Policy encoding structure is as follows: Policy encoding structure is as follows:
SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint> SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint>
Attributes: Attributes:
Tunnel Encaps Attribute (23) Tunnel Encaps Attribute (23)
Tunnel Type: SR Policy Tunnel Type: SR Policy
Binding SID Binding SID
skipping to change at page 4, line 9 skipping to change at page 4, line 25
Weight Weight
Segment Segment
Segment Segment
... ...
... ...
An SR path can be specified by an Segment List sub-TLV that contains An SR path can be specified by an Segment List sub-TLV that contains
a set of segment sub-TLVs and other sub-TLVs as shown above. As a set of segment sub-TLVs and other sub-TLVs as shown above. As
defined in [I-D.ietf-spring-segment-routing-policy], a candidate path defined in [I-D.ietf-spring-segment-routing-policy], a candidate path
includes multiple SR paths specified by SID list. The Path Segment includes multiple SR paths specified by SID list. The Path Segment
can be used for idendifying an SR path(specified by SID list). Also, can be used for identifying an SR path(specified by SID list) from
it can be used for identifying an SR candidate path or an SR Policy the headend and the tailend. Also, it can be used for identifying an
in some use cases if needed. New SR Policy encoding structure is SR candidate path in some use cases if needed. This document defines
expressed as below: a new Path Segment sub-TLV within Segment List sub-TLV, the details
will be described at section 3.1. The new SR Policy encoding
structure with Path Segmentg sub-TLV is expressed as below:
SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint> SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint>
Attributes: Attributes:
Tunnel Encaps Attribute (23) Tunnel Encaps Attribute (23)
Tunnel Type: SR Policy Tunnel Type: SR Policy
Binding SID Binding SID
Preference Preference
Priority Priority
Policy Name Policy Name
Explicit NULL Label Policy (ENLP) Explicit NULL Label Policy (ENLP)
Path Segment
Segment List Segment List
Weight Weight
Path Segment Path Segment
Segment Segment
Segment Segment
... ...
Segment List Segment List
Weight Weight
Path Segment Path Segment
Segment Segment
Segment Segment
... ...
... ...
The Path Segment can appear at both segment-list level and candidate The Path Segment is used to identified an SR path, and it can be used
path level, and generally it SHOULD also appear only at one level in OAM or IOAM use cases. When all the SID Lists within a candidate
depending upon use case. Path segment at segment list level and at path share the same Path Segment ID, the Path Segment can be used to
candidate path level may be same or may be different based on usecase collect the aggregated information of the candidate path. Multiple
and the ID allocation scope. When multiple Path Segments appear in Path Segment MAY be included in a Segment List for different use
both levels, it means the the Path Segment associated with candidate cases, all of them SHOULD be inserted into the SID List.
path and segment list SHOULD both be inserted into the SID list.
3.1. SR Path Segment Sub-TLV 3.1. SR Path Segment Sub-TLV
This section defines an SR Path Segment sub-TLV. This section defines an SR Path Segment sub-TLV.
An SR Path Segment sub-TLV can be included in the segment list sub- An SR Path Segment sub-TLV is included in the segment list sub-TLV to
TLV to identify an SID list, and it MUST appear only once within a identify an SID list. It has the following format:
Segment List sub-TLV. It has the following format:
0 1 2 3 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 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 | Flag | ST | | Type | Length | Flags | ST |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Path Segment (Variable depends on ST) | | Path Segment ID (Variable depends on ST) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1. Path Segment sub-TLV Figure 1. Path Segment sub-TLV
Where: Where:
Type: to be assigned by IANA (suggested value 10). Type: to be assigned by IANA.
Length: the total length of the value field not including Type and Length: the total length of the value field not including Type and
Length fields. Length fields.
Flag: 8 bits of flags. Following flags are defined: Flags: 8 bits of flags. Following flags are defined:
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+--+--+--+--+--+--+--+--+ +--+--+--+--+--+--+--+--+
| Reserved |G | | Reserved |G |
+--+--+--+--+--+--+--+--+ +--+--+--+--+--+--+--+--+
G-Flag: Global flag. Set when the Path Segment is global within an G-Flag: Global flag. Set when the Path Segment is global within an
SR domain. SR domain. The rest bits of Flag are reserved and MUST be set to 0
on transmission and MUST be ignored on receipt.
Reserved: 5 bits reserved and MUST be set to 0 on transmission and
MUST be ignored on receipt.
ST: Segment type, specifies the type of the Path Segment, and it has ST: Segment type, specifies the type of the Path Segment, and it has
following types: following types:
o 0: SR-MPLS Path Segment o 0: SR-MPLS Path Segment
o 1-255:Reserved o 1-255:Reserved
Path Segment: The Path Segment of an SR path. The Path Segment type Path Segment ID: The Path Segment ID of an SR path. The Path Segment
is indicated by the Segment Type(ST) field. It can be a Path Segment type is indicated by the Segment Type(ST) field. It can be a Path
in SR-MPLS [I-D.ietf-spring-mpls-path-segment], which is 32-bits Segment in SR-MPLS [I-D.ietf-spring-mpls-path-segment], or other IDs
value, which is a 128-bits value, or other IDs that can identify a that identifies a path. When ST is 0, the Path Segment ID is a SR-
path. MPLS Path Segment, and format is shown below.
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 | Flags | ST=0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Path Segment Label | TC |S| TTL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2. SR-MPLS Path Segment sub-TLV
4. SR Policy for Bidirectional Path 4. SR Policy for Bidirectional Path
In some scenarios, for example, mobile backhaul transport network, In some scenarios, for example, mobile backhaul transport network,
there are requirements to support bidirectional path. In SR, a there are requirements to support bidirectional path. In SR, a
bidirectional path can be represented as a binding of two bidirectional path can be represented as a binding of two
unidirectional SR paths. This document also defines new sub-TLVs to unidirectional SR paths. This document also defines a Reverse
describe an SR bidirectional path. An SR policy carrying SR Segment List sub-TLV to describe the reverse path associated with the
forward path specified by the Segment List. An SR policy carrying SR
bidirectional path information is expressed as below: bidirectional path information is expressed as below:
SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint> SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint>
Attributes: Tunnel Encaps Attribute (23) Attributes: Tunnel Encaps Attribute (23)
Tunnel Type: SR Policy Tunnel Type: SR Policy
Binding SID Binding SID
Preference Preference
Priority Priority
Policy Name Policy Name
Explicit NULL Label Policy (ENLP) Explicit NULL Label Policy (ENLP)
Bidirectioanl Path Segment List
Segment List Weight
Weight Path Segment
Path Segment Segment
Segment Segment
Segment ...
...
Reverse Segment List Reverse Segment List
Weight
Path Segment Path Segment
Segment Segment
Segment Segment
... ...
4.1. SR Bidirectional Path Sub-TLV 4.1. Reverse Path Segment List Sub-TLV
This section defines an SR bidirectional path sub-TLV to specify a
bidirectional path, which contains a Segment List sub-TLV
[I-D.ietf-idr-segment-routing-te-policy] and an associated Reverse
Path Segment List as defined at section 4.2. The SR bidirectional
path sub-TLV has the following format:
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2. SR Bidirectional path sub-TLV
Where:
Type: TBA, and the suggest value is 14.
Length: the total length of the sub-TLVs encoded within the SR
Bidirectional Path Sub-TLV not including Type and Length fields.
RESERVED: 1 octet of reserved bits. SHOULD be unset on transmission
and MUST be ignored on receipt.
Sub-TLVs:
o An Segment List sub-TLV
o An associated Reverse Path Segment List sub-TLV
4.2. SR Reverse Path Segment List Sub-TLV
An SR Reverse Path Segment List sub-TLV is defined to specify an SR A Reverse Path Segment List sub-TLV is defined to specify an SR
reverse path associated with the path specified by the Segment List reverse path associated with the path specified by the Segment List,
in the same SR Bidirectional Path Sub-TLV, and it has the following and it has the following format:
format:
0 1 2 3 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 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 | | Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (Variable) | | Sub-TLVs (Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2. SR Reverse Path Segment List Sub-TLV Figure 3. SR Reverse Path Segment List Sub-TLV
where: where:
Type: TBA, and suggest value is 127. Type: TBA.
Length: the total length of the sub-TLVs encoded within the SR Length: the total length of the sub-TLVs encoded within the Reverse
Reverse Path Segment List Sub-TLV not including the Type and Length Path Segment List Sub-TLV not including the Type and Length fields.
fields.
RESERVED: 1 octet of reserved bits. SHOULD be unset on transmission RESERVED: 1 octet of reserved bits. SHOULD be unset on transmission
and MUST be ignored on receipt. and MUST be ignored on receipt.
sub-TLVs, reuse the sub-TLVs in Segment List defined in sub-TLVs, reuse the sub-TLVs in Segment List defined in
[I-D.ietf-idr-segment-routing-te-policy]. [I-D.ietf-idr-segment-routing-te-policy].
o An optional single Weight sub-TLV. o One or more mandatory SR Path Segment sub-TLVs that contains the
Path Segments of the reverse SR path.
o An mandatory SR Path Segment sub-TLV that contains the Path
Segment of the reverse SR path.
o Zero or more Segment sub-TLVs to specify the reverse SR path. o One or more Segment sub-TLVs to specify the reverse SR path.
The Segment sub-TLVs in the Reverse Path Segment List sub-TLV The Segment sub-TLVs in the Reverse Path Segment List sub-TLV
provides the information of the reverse SR path, which can be used provides the information of the reverse SR path, which can be used
for directing egress BFD peer to use specific path for the reverse for directing egress BFD peer to use specific path for the reverse
direction of the BFD session [I-D.ietf-mpls-bfd-directed] or other direction of the BFD session [I-D.ietf-mpls-bfd-directed] or other
applications. applications.
5. Operations 5. Operations
The document does not bring new operation beyong the description of The document does not bring new operation beyond the description of
operations defined in [I-D.ietf-idr-segment-routing-te-policy]. The operations defined in [I-D.ietf-idr-segment-routing-te-policy]. The
existing operations defined in existing operations defined in
[I-D.ietf-idr-segment-routing-te-policy] can apply to this document [I-D.ietf-idr-segment-routing-te-policy] can apply to this document
directly. directly.
Typically but not limit to, the unidirectional or bidirectional SR Typically but not limit to, the unidirectional or bidirectional SR
policies carrying path identification infomation are configured by a policies carrying path identification infomation are configured by a
controller. controller.
After configuration, the unidirectional or bidirectional SR policies After configuration, the unidirectional or bidirectional SR policies
carrying path identification infomation will be advertised by BGP carrying path identification infomation will be advertised by BGP
update messages. The operation of advertisement is the same as update messages. The operation of advertisement is the same as
defined in [I-D.ietf-idr-segment-routing-te-policy], as well as the defined in [I-D.ietf-idr-segment-routing-te-policy], as well as the
receiption. reception.
The consumer of the unidirectional or bidirectional SR policies is The consumer of the unidirectional or bidirectional SR policies is
not the BGP process, it can be any applications, such as performance not the BGP process, it can be any applications, such as performance
measurement [I-D.gandhi-spring-udp-pm]. The operation of sending measurement [I-D.gandhi-spring-udp-pm]. The operation of sending
information to consumers is out of scope of this document. information to consumers is out of scope of this document.
6. IANA Considerations 6. IANA Considerations
This document defines new Sub-TLVs in following registries: This document defines new Sub-TLVs in following registries:
6.1. Existing Registry: BGP Tunnel Encapsulation Attribute sub-TLVs 6.1. Existing Registry: BGP Tunnel Encapsulation Attribute sub-TLVs
This document defines new sub-TLVs in the registry "BGP Tunnel
Encapsulation Attribute sub-TLVs" to be assigned by IANA:
Codepoint Description Reference
-------------------------------------------------------------
14 Path Segment sub-TLV This document
15 SR Bidirectional Path sub-TLV This document
127 Reverse Segment List sub-TLV This document
This document defines new sub-TLVs in the registry "SR Policy List This document defines new sub-TLVs in the registry "SR Policy List
Sub-TLVs" [I-D.ietf-idr-segment-routing-te-policy] to be assigned by Sub-TLVs" [I-D.ietf-idr-segment-routing-te-policy] to be assigned by
IANA: IANA:
Codepoint Description Reference Codepoint Description Reference
------------------------------------------------------------- -------------------------------------------------------------
14 Path Segment sub-TLV This document TBA Path Segment sub-TLV This document
TBA Reverse Segment List sub-TLV This document
7. Security Considerations 7. Security Considerations
TBA TBA
8. Contributors 8. Contributors
Mach(Guoyi) Chen Mach(Guoyi) Chen
Huawei Technologies Huawei Technologies
Huawei Campus, No. 156 Beiqing Rd. Huawei Campus, No. 156 Beiqing Rd.
Beijing 100095 Beijing 100095
China China
Email: Mach.chen@huawei.com Email: Mach.chen@huawei.com
Jie Dong Jie Dong
Huawei Technologies Huawei Technologies
skipping to change at page 10, line 38 skipping to change at page 10, line 15
9. Acknowledgements 9. Acknowledgements
Many thanks to Shraddha Hedge for her detailed review and Many thanks to Shraddha Hedge for her detailed review and
professional comments. professional comments.
10. References 10. References
10.1. Normative References 10.1. Normative References
[I-D.ietf-idr-segment-routing-te-policy] [I-D.ietf-idr-segment-routing-te-policy]
Previdi, S., Filsfils, C., Mattes, P., Rosen, E., Jain, Previdi, S., Filsfils, C., Talaulikar, K., Mattes, P.,
D., and S. Lin, "Advertising Segment Routing Policies in Rosen, E., Jain, D., and S. Lin, "Advertising Segment
BGP", draft-ietf-idr-segment-routing-te-policy-07 (work in Routing Policies in BGP", draft-ietf-idr-segment-routing-
progress), July 2019. te-policy-09 (work in progress), May 2020.
[I-D.ietf-spring-mpls-path-segment] [I-D.ietf-spring-mpls-path-segment]
Cheng, W., Li, H., Chen, M., Gandhi, R., and R. Zigler, Cheng, W., Li, H., Chen, M., Gandhi, R., and R. Zigler,
"Path Segment in MPLS Based Segment Routing Network", "Path Segment in MPLS Based Segment Routing Network",
draft-ietf-spring-mpls-path-segment-01 (work in progress), draft-ietf-spring-mpls-path-segment-02 (work in progress),
September 2019. February 2020.
[I-D.ietf-spring-segment-routing-policy] [I-D.ietf-spring-segment-routing-policy]
Filsfils, C., Sivabalan, S., daniel.voyer@bell.ca, d., Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and
bogdanov@google.com, b., and P. Mattes, "Segment Routing P. Mattes, "Segment Routing Policy Architecture", draft-
Policy Architecture", draft-ietf-spring-segment-routing- ietf-spring-segment-routing-policy-08 (work in progress),
policy-03 (work in progress), May 2019. July 2020.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[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>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>. July 2018, <https://www.rfc-editor.org/info/rfc8402>.
10.2. Informative References 10.2. Informative References
[I-D.gandhi-spring-udp-pm] [I-D.gandhi-spring-udp-pm]
Gandhi, R., Filsfils, C., daniel.voyer@bell.ca, d., Gandhi, R., Filsfils, C., daniel.voyer@bell.ca, d.,
Salsano, S., Ventre, P., and M. Chen, "UDP Path for In- Salsano, S., Ventre, P., and M. Chen, "UDP Path for In-
band Performance Measurement for Segment Routing band Performance Measurement for Segment Routing
Networks", draft-gandhi-spring-udp-pm-02 (work in Networks", draft-gandhi-spring-udp-pm-02 (work in
progress), September 2018. progress), September 2018.
[I-D.ietf-mpls-bfd-directed] [I-D.ietf-mpls-bfd-directed]
Mirsky, G., Tantsura, J., Varlashkin, I., and M. Chen, Mirsky, G., Tantsura, J., Varlashkin, I., and M. Chen,
"Bidirectional Forwarding Detection (BFD) Directed Return "Bidirectional Forwarding Detection (BFD) Directed Return
Path", draft-ietf-mpls-bfd-directed-12 (work in progress), Path for MPLS Label Switched Paths (LSPs)", draft-ietf-
August 2019. mpls-bfd-directed-15 (work in progress), August 2020.
Authors' Addresses Authors' Addresses
Cheng Li Cheng Li
Huawei Technologies Huawei Technologies
Huawei Campus, No. 156 Beiqing Rd. Huawei Campus, No. 156 Beiqing Rd.
Beijing 100095 Beijing 100095
China China
Email: chengli13@huawei.com Email: c.l@huawei.com
Zhenbin Li Zhenbin Li
Huawei Technologies Huawei Technologies
Huawei Campus, No. 156 Beiqing Rd. Huawei Campus, No. 156 Beiqing Rd.
Beijing 100095 Beijing 100095
China China
Email: lizhenbin@huawei.com Email: lizhenbin@huawei.com
Huanan Chen Huanan Chen
China Telecom China Telecom
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