Label Switched Path (LSP) Ping for Segment Routing (SR) Path Segment Identifiers (SIDs) with MPLS Data Planes
draft-xp-mpls-spring-lsp-ping-path-sid-03
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
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|
|---|---|---|---|
| Authors | Xiao Min , Shaofu Peng | ||
| Last updated | 2022-03-04 | ||
| Replaced by | draft-ietf-mpls-spring-lsp-ping-path-sid | ||
| RFC stream | (None) | ||
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draft-xp-mpls-spring-lsp-ping-path-sid-03
MPLS Working Group X. Min
Internet-Draft S. Peng
Intended status: Standards Track ZTE Corp.
Expires: 5 September 2022 4 March 2022
Label Switched Path (LSP) Ping for Segment Routing (SR) Path Segment
Identifiers (SIDs) with MPLS Data Planes
draft-xp-mpls-spring-lsp-ping-path-sid-03
Abstract
Path Segment is a type of SR segment, which is used to identify an SR
path. This document provides Target Forwarding Equivalence Class
(FEC) stack TLV definitions for Path Segment Identifiers.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 5 September 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Please review these documents carefully, as they describe your rights
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provided without warranty as described in the Revised BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 2
2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
3. Path Segment ID Sub-TLV . . . . . . . . . . . . . . . . . . . 3
3.1. SR Policy's Path SID . . . . . . . . . . . . . . . . . . 3
3.2. SR Candidate Path's Path SID . . . . . . . . . . . . . . 5
3.3. SR Segment List's Path SID . . . . . . . . . . . . . . . 7
4. Path-SID FEC Validation . . . . . . . . . . . . . . . . . . . 9
5. Security Considerations . . . . . . . . . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . 14
8.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Path Segment is a type of SR segment, which is used to identify an SR
path. Path Segment in MPLS based segment routing network is defined
in [I-D.ietf-spring-mpls-path-segment].
When Path Segment is used, it's inserted by the ingress node of the
SR path, and then processed by the egress node of the SR path. The
position of Path Segment Label within the MPLS label stack is
immediately following the segment list of the SR path. Note that the
Path Segment would not be popped up until it reaches the egress node.
This document provides Target Forwarding Equivalence Class (FEC)
stack TLV definitions for Path-SIDs. Procedures for LSP Ping as
defined in [RFC8287] and [RFC8690] are applicable to Path-SIDs as
well.
2. Conventions
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.
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2.2. Terminology
This document uses the terminology defined in [RFC8402] and
[RFC8029], readers are expected to be familiar with those terms.
3. Path Segment ID Sub-TLV
Analogous to what's defined in Section 5 of [RFC8287] and Section 4
of [I-D.ietf-mpls-sr-epe-oam], three new sub-TLVs are defined for the
Target FEC Stack TLV (Type 1), the Reverse-Path Target FEC Stack TLV
(Type 16), and the Reply Path TLV (Type 21).
Sub-Type Sub-TLV Name
-------- -----------------------------
TBD1 SR Policy's Path SID
TBD2 SR Candidate Path's Path SID
TBD3 SR Segment List's Path SID
As specified in Section 2 of [I-D.ietf-spring-mpls-path-segment], the
Path Segment may be used to identify an SR Policy, its Candidate
Path, or a Segment List, so three different Target FEC sub-TLVs need
to be defined for Path Segment ID. When a Path Segment is used to
identify an SR Policy, the Target FEC sub-TLV of SR Policy's Path SID
would be used to validate the control plane to forwarding plane
synchronization for this Path-SID; When a Path Segment is used to
identify an SR Candidate Path, the Target FEC sub-TLV of SR Candidate
Path's Path SID would be used to validate the control plane to
forwarding plane synchronization for this Path-SID; When a Path
Segment is used to identify a Segment List, the Target FEC sub-TLV of
SR Segment List's Path SID would be used to validate the control
plane to forwarding plane synchronization for this Path-SID. Note
that the three new Target FEC sub-TLVs are mutual exclusive and they
wouldn't be present in one message simultaneously.
3.1. SR Policy's Path SID
The format of SR Policy's Path SID sub-TLV is as specified below:
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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 = TBD1 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Headend (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Color (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Endpoint (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: SR Policy's Path SID sub-TLV
Type
This field is set to the value (TBD1) which indicates that it's an
SR Policy's Path SID sub-TLV.
Length
This field is set to the length of the sub-TLV's Value field in
octets. If Headend and Endpoint fields are in IPv4 address format
which is 4 octets long, it MUST be set to 12; If Headend and
Endpoint fields are in IPv6 address format which is 16 octets
long, it MUST be set to 36.
Headend
This field identifies the headend of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The headend is a
4-octet IPv4 address or a 16-octet IPv6 address.
Color
This field associates the SR Policy with an intent, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The color is a 4-octet
numerical value.
Endpoint
This field identifies the endpoint of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The endpoint is a
4-octet IPv4 address or a 16-octet IPv6 address.
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3.2. SR Candidate Path's Path SID
The format of SR Candidate Path's Path SID sub-TLV is as specified
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 = TBD2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Headend (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Color (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Endpoint (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Protocol-Origin| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| Originator (20 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Discriminator (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: SR Candidate Path's Path SID sub-TLV
Type
This field is set to the value (TBD2) which indicates that it's an
SR Candidate Path's Path SID sub-TLV.
Length
This field is set to the length of the sub-TLV's Value field in
octets. If Headend and Endpoint fields are in IPv4 address format
which is 4 octets long, it MUST be set to 40; If Headend and
Endpoint fields are in IPv6 address format which is 16 octets
long, it MUST be set to 64.
Headend
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This field identifies the headend of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The headend is a
4-octet IPv4 address or a 16-octet IPv6 address.
Color
This field associates the SR Policy with an intent, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The color is a 4-octet
numerical value.
Endpoint
This field identifies the endpoint of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The endpoint is a
4-octet IPv4 address or a 16-octet IPv6 address.
Protocol-Origin
This field identifies the component or protocol that originates or
signals the candidate path for an SR Policy, the same as defined
in Section 2.3 of [I-D.ietf-spring-segment-routing-policy]. The
protocol-origin is a 1-octet value that follows the recommendation
from Table 1 of Section 2.3 of
[I-D.ietf-spring-segment-routing-policy], which specifies value 10
for "PCEP", value 20 for "BGP SR Policy" and value 30 for "Via
Configuration".
Originator
This field identifies the node which provisioned or signaled the
candidate path for an SR Policy, the same as defined in
Section 2.4 of [I-D.ietf-spring-segment-routing-policy]. The
originator is a 20-octet numerical value formed by the
concatenation of the fields of the tuple <ASN, node-address>,
among which ASN is a 4-octet number and node address is a 16-octet
value (an IPv6 address or an IPv4 address encoded in the lowest 4
octets). When Procotol-Origin is respectively "Via
Configuration", or "PCEP", or "BGP SR Policy", the values of ASN
and node address follow the specification in Section 2.4 of
[I-D.ietf-spring-segment-routing-policy].
Discriminator
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This field uniquely identifies a candidate path within the context
of an SR policy, the same as defined in Section 2.5 of
[I-D.ietf-spring-segment-routing-policy]. The discriminator is a
4-octet value. When Protocol-Origin is respectively "Via
Configuration", or "PCEP", or "BGP SR Policy", the value of
discriminator follows the specification in Section 2.5 of
[I-D.ietf-spring-segment-routing-policy].
3.3. SR Segment List's Path SID
The format of SR Segment List's Path SID sub-TLV is as specified
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 = TBD3 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Headend (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Color (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Endpoint (4/16 octets) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Protocol-Origin| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| Originator (20 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Discriminator (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Segment-List-ID (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: SR Segment List's Path SID sub-TLV
Type
This field is set to the value (TBD3) which indicates that it's an
SR Segment List's Path SID sub-TLV.
Length
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This field is set to the length of the sub-TLV's Value field in
octets. If Headend and Endpoint fields are in IPv4 address format
which is 4 octets long, it MUST be set to 44; If Headend and
Endpoint fields are in IPv6 address format which is 16 octets
long, it MUST be set to 68.
Headend
This field identifies the headend of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The headend is a
4-octet IPv4 address or a 16-octet IPv6 address.
Color
This field associates the SR Policy with an intent, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The color is a 4-octet
numerical value.
Endpoint
This field identifies the endpoint of an SR Policy, the same as
defined in Section 2.1 of
[I-D.ietf-spring-segment-routing-policy]. The endpoint is a
4-octet IPv4 address or a 16-octet IPv6 address.
Protocol-Origin
This field identifies the component or protocol that originates or
signals the candidate path for an SR Policy, the same as defined
in Section 2.3 of [I-D.ietf-spring-segment-routing-policy]. The
protocol-origin is a 1-octet value that follows the recommendation
from Table 1 of Section 2.3 of
[I-D.ietf-spring-segment-routing-policy], which specifies value 10
for "PCEP", value 20 for "BGP SR Policy" and value 30 for "Via
Configuration".
Originator
This field identifies the node which provisioned or signaled the
candidate path for an SR Policy, the same as defined in
Section 2.4 of [I-D.ietf-spring-segment-routing-policy]. The
originator is a 20-octet numerical value formed by the
concatenation of the fields of the tuple <ASN, node-address>,
among which ASN is a 4-octet number and node address is a 16-octet
value (an IPv6 address or an IPv4 address encoded in the lowest 4
octets). When Procotol-Origin is respectively "Via
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Configuration", or "PCEP", or "BGP SR Policy", the values of ASN
and node address follow the specification in Section 2.4 of
[I-D.ietf-spring-segment-routing-policy].
Discriminator
This field uniquely identifies a candidate path within the context
of an SR policy, the same as defined in Section 2.5 of
[I-D.ietf-spring-segment-routing-policy]. The discriminator is a
4-octet value. When Protocol-Origin is respectively "Via
Configuration", or "PCEP", or "BGP SR Policy", the value of
discriminator follows the specification in Section 2.5 of
[I-D.ietf-spring-segment-routing-policy].
Segment-List-ID
This field identifies an SR path within the context of a candidate
path of an SR Policy, the same as "Path ID" defined in Section 4.2
of [I-D.ietf-pce-multipath], or "List Identifier" defined in
Section 2.2 of [I-D.lp-idr-sr-path-protection]. The segment-list-
ID is a 4-octet identifier of the corresponding segment list.
4. Path-SID FEC Validation
The MPLS LSP Ping procedures MAY be initiated by the headend of the
Segment Routing path or a centralized topology-aware data plane
monitoring system as described in [RFC8403]. For the Path-SID, the
responder nodes that receive echo request and send echo reply MUST be
the endpoint of the Segment Routing path.
When an endpoint receives the LSP echo request packet with top FEC
being the Path-SID, it SHOULD perform validity checks on the content
of the Path-SID FEC sub-TLV. The basic length check should be
performed on the received FEC.
SR Policy's Path SID
------------------
Length = 12 or 36
SR Candidate Path's Path SID
------------------
Length = 40 or 64
SR Segment List's Path SID
------------------
Length = 44 or 68
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If a malformed FEC sub-TLV is received, then a return code of 1,
"Malformed echo request received" as defined in [RFC8029] SHOULD be
sent. The below section augments the section 7.4 of [RFC8287].
4a. Segment Routing Path-SID Validation:
If the Label-stack-depth is 0 and the Target FEC Stack sub-TLV at
FEC-stack-depth is TBD1 (SR Policy's Path SID sub-TLV), {
- Set the Best-return-code to 10, "Mapping for this FEC is not
the given label at stack-depth <RSC>" if any below conditions
fail:
o Validate that the Path Segment ID is signaled or provisioned
for the SR Policy {
+ Validate that the signaled or provisioned headend, color
and end-point for the Path SID, matches with the
corresponding fields in the received SR Policy's Path SID
sub-TLV.
}
}
- If all the above validations have passed, set the return code
to 3 "Replying router is an egress for the FEC at stack-depth
<RSC>".
- Set FEC-Status to 1 and return.
}
Else, if the Label-stack-depth is 0 and the Target FEC Stack sub-
TLV at FEC-stack-depth is TBD2 (SR Candidate Path's Path SID sub-
TLV), {
- Set the Best-return-code to 10, "Mapping for this FEC is not
the given label at stack-depth <RSC>" if any below conditions
fail:
o Validate that the Path Segment ID is signaled or provisioned
for the SR Candidate Path {
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+ When the Protocol-Origin field in the received SR
Candidate Path's Path SID sub-TLV is 10, "PCEP" is used
as the signaling protocol. And then validate that the
Path Segment ID matches with the tuple identifying the SR
Candidate Path within PCEP {
* Validate that the signaled headend, color, end-point,
originator ASN, originator address and discriminator
defined in [I-D.ietf-pce-segment-routing-policy-cp]
and [I-D.ietf-pce-sr-path-segment], for the Path SID,
matches with the corresponding fields in the received
SR Candidate Path's Path SID sub-TLV.
}
+ When the Protocol-Origin field in the received SR
Candidate Path's Path SID sub-TLV is 20, "BGP SR Policy"
is used as the signaling protocol. And then validate
that the Path Segment ID matches with the tuple
identifying the SR Candidate Path within BGP SR Policy {
* Validate that the signaled headend, policy color,
endpoint, ASN, BGP Router-ID and distinguisher defined
in [I-D.ietf-idr-segment-routing-te-policy] and
[I-D.ietf-idr-sr-policy-path-segment], for the Path
SID, matches with the corresponding fields in the
received SR Candidate Path's Path SID sub-TLV.
}
+ When the Protocol-Origin field in the received SR
Candidate Path's Path SID sub-TLV is 30, "Via
Configuration" is used. And then validate that the Path
Segment ID matches with the tuple identifying the SR
Candidate Path within Configuration {
* Validate that the provisioned headend, color,
endpoint, originator and discriminator defined in
[I-D.ietf-spring-sr-policy-yang], for the Path SID,
matches with the corresponding fields in the received
SR Candidate Path's Path SID sub-TLV.
}
}
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- If all the above validations have passed, set the return code
to 3 "Replying router is an egress for the FEC at stack-depth
<RSC>".
- Set FEC-Status to 1 and return.
}
Else, if the Label-stack-depth is 0 and the Target FEC Stack sub-
TLV at FEC-stack-depth is TBD3 (SR Segment List's Path SID sub-
TLV), {
- Set the Best-return-code to 10, "Mapping for this FEC is not
the given label at stack-depth <RSC>" if any below conditions
fail:
o Validate that the Path Segment ID is signaled or provisioned
for the SR Segment List {
+ When the Protocol-Origin field in the received SR Segment
List's Path SID sub-TLV is 10, "PCEP" is used as the
signaling protocol. And then validate that the Path
Segment ID matches with the tuple identifying the SR
Segment List within PCEP {
* Validate that the signaled headend, color, end-point,
originator ASN, originator address and discriminator
defined in [I-D.ietf-pce-segment-routing-policy-cp]
and [I-D.ietf-pce-sr-path-segment], and the signaled
Path ID defined in [I-D.ietf-pce-multipath], for the
Path SID, matches with the corresponding fields in the
received SR Segment List's Path SID sub-TLV.
}
+ When the Protocol-Origin field in the received SR Segment
List's Path SID sub-TLV is 20, "BGP SR Policy" is used as
the signaling protocol. And then validate that the Path
Segment ID matches with the tuple identifying the SR
Segment List within BGP SR Policy {
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* Validate that the signaled headend, policy color,
endpoint, ASN, BGP Router-ID and distinguisher defined
in [I-D.ietf-idr-segment-routing-te-policy] and
[I-D.ietf-idr-sr-policy-path-segment], and the
signaled List Identifier defined in
[I-D.lp-idr-sr-path-protection], for the Path SID,
matches with the corresponding fields in the received
SR Segment List's Path SID sub-TLV.
}
+ When the Protocol-Origin field in the received SR Segment
List's Path SID sub-TLV is 30, "Via Configuration" is
used. And then validate that the Path Segment ID matches
with the tuple identifying the SR Segment List within
Configuration {
* Validate that the provisioned headend, color,
endpoint, originator, discriminator and Segment-List-
ID defined in [I-D.ietf-spring-sr-policy-yang], for
the Path SID, matches with the corresponding fields in
the received SR Segment List's Path SID sub-TLV.
}
}
- If all the above validations have passed, set the return code
to 3 "Replying router is an egress for the FEC at stack-depth
<RSC>".
- Set FEC-Status to 1 and return.
}
5. Security Considerations
This document defines additional MPLS LSP Ping sub-TLVs and follows
the mechanisms defined in [RFC8029]. All the security considerations
defined in [RFC8029] will be applicable for this document and, in
addition, they do not impose any additional security challenges to be
considered.
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6. IANA Considerations
IANA is requested to assign three new sub-TLVs from the "sub-TLVs for
TLV Types 1, 16, and 21" subregistry of the "Multi-Protocol Label
Switching (MPLS) Label Switched Paths (LSPs) Ping Parameters"
registry [IANA].
Sub-Type Sub-TLV Name Reference
-------- ----------------------------- ------------
TBD1 SR Policy's Path SID Section 3.1
TBD2 SR Candidate Path's Path SID Section 3.2
TBD3 SR Segment List's Path SID Section 3.3
7. Acknowledgements
The authors would like to acknowledge Detao Zhao for his thorough
review and very helpful comments.
The authors would like to acknowledge Yao Liu for the very helpful
f2f discussion.
8. References
8.1. Normative References
[I-D.ietf-spring-mpls-path-segment]
Cheng, W., Li, H., Chen, M., Gandhi, R., and R. Zigler,
"Path Segment in MPLS Based Segment Routing Network", Work
in Progress, Internet-Draft, draft-ietf-spring-mpls-path-
segment-07, 20 December 2021,
<https://www.ietf.org/archive/id/draft-ietf-spring-mpls-
path-segment-07.txt>.
[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>.
[RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
Switched (MPLS) Data-Plane Failures", RFC 8029,
DOI 10.17487/RFC8029, March 2017,
<https://www.rfc-editor.org/info/rfc8029>.
[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>.
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[RFC8287] Kumar, N., Ed., Pignataro, C., Ed., Swallow, G., Akiya,
N., Kini, S., and M. Chen, "Label Switched Path (LSP)
Ping/Traceroute for Segment Routing (SR) IGP-Prefix and
IGP-Adjacency Segment Identifiers (SIDs) with MPLS Data
Planes", RFC 8287, DOI 10.17487/RFC8287, December 2017,
<https://www.rfc-editor.org/info/rfc8287>.
[RFC8690] Nainar, N., Pignataro, C., Iqbal, F., and A. Vainshtein,
"Clarification of Segment ID Sub-TLV Length for RFC 8287",
RFC 8690, DOI 10.17487/RFC8690, December 2019,
<https://www.rfc-editor.org/info/rfc8690>.
8.2. Informative References
[I-D.ietf-idr-segment-routing-te-policy]
Previdi, S., Filsfils, C., Talaulikar, K., Mattes, P.,
Jain, D., and S. Lin, "Advertising Segment Routing
Policies in BGP", Work in Progress, Internet-Draft, draft-
ietf-idr-segment-routing-te-policy-14, 10 November 2021,
<https://www.ietf.org/archive/id/draft-ietf-idr-segment-
routing-te-policy-14.txt>.
[I-D.ietf-idr-sr-policy-path-segment]
Li, C., Li, Z., Yin, Y., Cheng, W., and K. Talaulikar, "SR
Policy Extensions for Path Segment and Bidirectional
Path", Work in Progress, Internet-Draft, draft-ietf-idr-
sr-policy-path-segment-05, 23 January 2022,
<https://www.ietf.org/archive/id/draft-ietf-idr-sr-policy-
path-segment-05.txt>.
[I-D.ietf-mpls-sr-epe-oam]
Hegde, S., Arora, K., Srivastava, M., Ninan, S., and X.
Xu, "Label Switched Path (LSP) Ping/Traceroute for Segment
Routing (SR) Egress Peer Engineering Segment Identifiers
(SIDs) with MPLS Data Planes", Work in Progress, Internet-
Draft, draft-ietf-mpls-sr-epe-oam-04, 8 November 2021,
<https://www.ietf.org/archive/id/draft-ietf-mpls-sr-epe-
oam-04.txt>.
[I-D.ietf-pce-multipath]
Koldychev, M., Sivabalan, S., Saad, T., Beeram, V. P.,
Bidgoli, H., Yadav, B., Peng, S., and G. Mishra, "PCEP
Extensions for Signaling Multipath Information", Work in
Progress, Internet-Draft, draft-ietf-pce-multipath-04, 25
February 2022, <https://www.ietf.org/archive/id/draft-
ietf-pce-multipath-04.txt>.
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Internet-Draft LSP Ping for SR Path SID March 2022
[I-D.ietf-pce-segment-routing-policy-cp]
Koldychev, M., Sivabalan, S., Barth, C., Peng, S., and H.
Bidgoli, "PCEP extension to support Segment Routing Policy
Candidate Paths", Work in Progress, Internet-Draft, draft-
ietf-pce-segment-routing-policy-cp-06, 22 October 2021,
<https://www.ietf.org/archive/id/draft-ietf-pce-segment-
routing-policy-cp-06.txt>.
[I-D.ietf-pce-sr-path-segment]
Li, C., Chen, M., Cheng, W., Gandhi, R., and Q. Xiong,
"Path Computation Element Communication Protocol (PCEP)
Extension for Path Segment in Segment Routing (SR)", Work
in Progress, Internet-Draft, draft-ietf-pce-sr-path-
segment-05, 13 February 2022,
<https://www.ietf.org/archive/id/draft-ietf-pce-sr-path-
segment-05.txt>.
[I-D.ietf-spring-segment-routing-policy]
Filsfils, C., Talaulikar, K., Voyer, D., Bogdanov, A., and
P. Mattes, "Segment Routing Policy Architecture", Work in
Progress, Internet-Draft, draft-ietf-spring-segment-
routing-policy-18, 17 February 2022,
<https://www.ietf.org/archive/id/draft-ietf-spring-
segment-routing-policy-18.txt>.
[I-D.ietf-spring-sr-policy-yang]
Raza, K., Sawaya, R., Shunwan, Z., Voyer, D., Durrani, M.,
Matsushima, S., and V. P. Beeram, "YANG Data Model for
Segment Routing Policy", Work in Progress, Internet-Draft,
draft-ietf-spring-sr-policy-yang-01, 7 April 2021,
<https://www.ietf.org/archive/id/draft-ietf-spring-sr-
policy-yang-01.txt>.
[I-D.lp-idr-sr-path-protection]
Liu, Y. and S. Peng, "BGP Extensions of SR Policy for Path
Protection", Work in Progress, Internet-Draft, draft-lp-
idr-sr-path-protection-02, 19 December 2021,
<https://www.ietf.org/archive/id/draft-lp-idr-sr-path-
protection-02.txt>.
[IANA] Internet Assigned Numbers Authority (IANA), "Multi-
Protocol Label Switching (MPLS) Label Switched Paths
(LSPs) Ping Parameters", <http://www.iana.org/assignments/
mpls-lsp-ping-parameters/>.
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Internet-Draft LSP Ping for SR Path SID March 2022
[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>.
[RFC8403] Geib, R., Ed., Filsfils, C., Pignataro, C., Ed., and N.
Kumar, "A Scalable and Topology-Aware MPLS Data-Plane
Monitoring System", RFC 8403, DOI 10.17487/RFC8403, July
2018, <https://www.rfc-editor.org/info/rfc8403>.
Authors' Addresses
Xiao Min
ZTE Corp.
Nanjing
China
Phone: +86 25 88013062
Email: xiao.min2@zte.com.cn
Shaofu Peng
ZTE Corp.
Nanjing
China
Email: peng.shaofu@zte.com.cn
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