Internet DRAFT - draft-xzc-lsr-mpls-flc-frld
draft-xzc-lsr-mpls-flc-frld
LSR Working Group X. Min
Internet-Draft Z. Zhang
Intended status: Standards Track ZTE Corp.
Expires: 31 July 2024 W. Cheng
China Mobile
28 January 2024
Signaling Flow-ID Label Capability and Flow-ID Readable Label Depth
draft-xzc-lsr-mpls-flc-frld-04
Abstract
Flow-ID Label (FL) is used for MPLS flow identification and flow-
based performance measurement with alternate marking method. The
ability to process Flow-ID labels is called Flow-ID Label Capability
(FLC), and the capability of reading the maximum label stack depth
and performing FL-based performance measurement is called Flow-ID
Readable Label Depth (FRLD). This document defines a mechanism to
signal the FLC and the FRLD using IGP and BGP-LS.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 31 July 2024.
Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
Min, et al. Expires 31 July 2024 [Page 1]
Internet-Draft Signaling FLC and FRLD January 2024
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2
2. Advertising FLC Using IGP . . . . . . . . . . . . . . . . . . 3
2.1. Advertising FLC Using IS-IS . . . . . . . . . . . . . . . 3
2.2. Advertising FLC Using OSPF . . . . . . . . . . . . . . . 3
3. Advertising FRLD Using IGP . . . . . . . . . . . . . . . . . 4
4. Signaling FLC and FRLD in BGP-LS . . . . . . . . . . . . . . 4
5. Security Considerations . . . . . . . . . . . . . . . . . . . 4
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
8.1. Normative References . . . . . . . . . . . . . . . . . . 5
8.2. Informative References . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction
As specified in [I-D.ietf-mpls-inband-pm-encapsulation], Flow-ID
Label (FL) is used for MPLS flow identification and flow-based
performance measurement with alternate marking method.
Flow-ID Label may appear multiple times in a label stack with
variable depth, so both the Flow-ID Label Capability (FLC) and the
Flow-ID Readable Label Depth (FRLD) are defined in
[I-D.ietf-mpls-inband-pm-encapsulation].
Analogous to [RFC9088] and [RFC9089], this document defines a
mechanism to signal the FLC and the FRLD using IGP and BGP-LS.
Specifically, IGP includes IS-IS, OSPFv2 and OSPFv3.
1.1. Terminology
This memo makes use of the terms defined in
[I-D.ietf-mpls-inband-pm-encapsulation] and [RFC8491].
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.
Min, et al. Expires 31 July 2024 [Page 2]
Internet-Draft Signaling FLC and FRLD January 2024
2. Advertising FLC Using IGP
FLC is a property of the node, so FLC is advertised with a node in
this document.
If a router has multiple interfaces, the router MUST NOT announce FLC
unless all of its interfaces are capable of processing FL.
2.1. Advertising FLC Using IS-IS
[RFC8667] defines an SR-Capabilities sub-TLV of the IS-IS Router
Capability TLV as defined in [RFC7981]. Bit 2 in the Flags field of
the SR-Capabilities sub-TLV is used as the FLC Flag (F-Flag), as
shown in Figure 1.
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|I|V|F| |
+-+-+-+-+-+-+-+-+
Figure 1: Flags field of the SR-Capabilities sub-TLV
F-Flag:
FLC Flag (Bit 2) - Set for the originating node if it supports FLC
on all interfaces.
2.2. Advertising FLC Using OSPF
[RFC8665] defines some SR Capabilities TLVs as top-level TLVs of the
Router Information Opaque LSA as defined in [RFC7770]. The SR
Capabilities TLVs are applicable to both OSPFv2 and OSPFv3 (see also
[RFC8666]). Within the SR Capabilities TLVs, the SID/Label Range TLV
has a 1-octet Reserved field. Bit 0 in the Reserved field of the
SID/Label Range TLV is used as the FLC Flag (F-Flag), as shown in
Figure 2.
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|F| |
+-+-+-+-+-+-+-+-+
Figure 2: Reserved field of the SID/Label Range TLV
F-Flag:
FLC Flag (Bit 0) - Set for the originating node if it supports FLC
on all interfaces.
Min, et al. Expires 31 July 2024 [Page 3]
Internet-Draft Signaling FLC and FRLD January 2024
3. Advertising FRLD Using IGP
As requested by [RFC8491], IANA has created an IANA-managed registry
titled "IGP MSD-Types" to identify MSD-Types. A new MSD-Type, called
FRLD-MSD, is defined to advertise the FRLD of a given router. The
MSD-Type code 3 is requested to be assigned by IANA for FRLD-MSD.
The MSD-Value field is set to the FRLD in the range between 0 to 255.
If a router has multiple interfaces with different capabilities of
reading the maximum label stack depth, the router MUST advertise the
smallest value found across all of its interfaces.
For IS-IS, the FRLD is advertised in a Node MSD Sub-TLV [RFC8491]
using the FRLD-MSD type.
For OSPF including both OSPFv2 and OSPFv3, the FRLD is advertised in
a Node MSD TLV [RFC8476] using the FRLD-MSD type.
The absence of FRLD-MSD advertisements indicates only that the
advertising node does not support advertisement of this capability.
4. Signaling FLC and FRLD in BGP-LS
The IGP extensions defined in this document can be advertised via
BGP-LS (Distribution of Link-State and Traffic Engineering
Information Using BGP) [RFC9552] using existing BGP-LS TLVs.
The FLC is advertised using the SR Capabilities TLV as defined in
[RFC9085].
The FRLD-MSD is advertised using the Node MSD TLV as defined in
[RFC8814].
5. Security Considerations
This document specifies the ability to advertise additional node
capabilities using IS-IS, OSPF and BGP-LS. As such, the security
considerations as described in the referenced specifications are
applicable to this document.
Incorrectly setting the F-Flag during origination, propagation, or
redistribution may lead to poor or no performance measurement of the
MPLS traffic or to the MPLS traffic being discarded on the egress
node.
Incorrectly setting the FRLD value may lead to poor or no performance
measurement of the MPLS traffic.
Min, et al. Expires 31 July 2024 [Page 4]
Internet-Draft Signaling FLC and FRLD January 2024
6. IANA Considerations
This document requests the following allocation from IANA:
* Type 3 in the IGP MSD-Types registry is requested to be assigned
to the FRLD-MSD.
7. Acknowledgements
The authors would like to acknowledge Acee Lindem and Les Ginsberg
for their very helpful comments.
8. References
8.1. Normative References
[I-D.ietf-mpls-inband-pm-encapsulation]
Cheng, W., Min, X., Zhou, T., Dai, J., and Y. Peleg,
"Encapsulation For MPLS Performance Measurement with
Alternate Marking Method", Work in Progress, Internet-
Draft, draft-ietf-mpls-inband-pm-encapsulation-08, 26
January 2024, <https://datatracker.ietf.org/doc/html/
draft-ietf-mpls-inband-pm-encapsulation-08>.
[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>.
[RFC7770] Lindem, A., Ed., Shen, N., Vasseur, JP., Aggarwal, R., and
S. Shaffer, "Extensions to OSPF for Advertising Optional
Router Capabilities", RFC 7770, DOI 10.17487/RFC7770,
February 2016, <https://www.rfc-editor.org/info/rfc7770>.
[RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions
for Advertising Router Information", RFC 7981,
DOI 10.17487/RFC7981, October 2016,
<https://www.rfc-editor.org/info/rfc7981>.
[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>.
[RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476,
DOI 10.17487/RFC8476, December 2018,
<https://www.rfc-editor.org/info/rfc8476>.
Min, et al. Expires 31 July 2024 [Page 5]
Internet-Draft Signaling FLC and FRLD January 2024
[RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491,
DOI 10.17487/RFC8491, November 2018,
<https://www.rfc-editor.org/info/rfc8491>.
[RFC8665] Psenak, P., Ed., Previdi, S., Ed., Filsfils, C., Gredler,
H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", RFC 8665,
DOI 10.17487/RFC8665, December 2019,
<https://www.rfc-editor.org/info/rfc8665>.
[RFC8666] Psenak, P., Ed. and S. Previdi, Ed., "OSPFv3 Extensions
for Segment Routing", RFC 8666, DOI 10.17487/RFC8666,
December 2019, <https://www.rfc-editor.org/info/rfc8666>.
[RFC8667] Previdi, S., Ed., Ginsberg, L., Ed., Filsfils, C.,
Bashandy, A., Gredler, H., and B. Decraene, "IS-IS
Extensions for Segment Routing", RFC 8667,
DOI 10.17487/RFC8667, December 2019,
<https://www.rfc-editor.org/info/rfc8667>.
[RFC8814] Tantsura, J., Chunduri, U., Talaulikar, K., Mirsky, G.,
and N. Triantafillis, "Signaling Maximum SID Depth (MSD)
Using the Border Gateway Protocol - Link State", RFC 8814,
DOI 10.17487/RFC8814, August 2020,
<https://www.rfc-editor.org/info/rfc8814>.
[RFC9085] Previdi, S., Talaulikar, K., Ed., Filsfils, C., Gredler,
H., and M. Chen, "Border Gateway Protocol - Link State
(BGP-LS) Extensions for Segment Routing", RFC 9085,
DOI 10.17487/RFC9085, August 2021,
<https://www.rfc-editor.org/info/rfc9085>.
[RFC9552] Talaulikar, K., Ed., "Distribution of Link-State and
Traffic Engineering Information Using BGP", RFC 9552,
DOI 10.17487/RFC9552, December 2023,
<https://www.rfc-editor.org/info/rfc9552>.
8.2. Informative References
[RFC9088] Xu, X., Kini, S., Psenak, P., Filsfils, C., Litkowski, S.,
and M. Bocci, "Signaling Entropy Label Capability and
Entropy Readable Label Depth Using IS-IS", RFC 9088,
DOI 10.17487/RFC9088, August 2021,
<https://www.rfc-editor.org/info/rfc9088>.
Min, et al. Expires 31 July 2024 [Page 6]
Internet-Draft Signaling FLC and FRLD January 2024
[RFC9089] Xu, X., Kini, S., Psenak, P., Filsfils, C., Litkowski, S.,
and M. Bocci, "Signaling Entropy Label Capability and
Entropy Readable Label Depth Using OSPF", RFC 9089,
DOI 10.17487/RFC9089, August 2021,
<https://www.rfc-editor.org/info/rfc9089>.
Authors' Addresses
Xiao Min
ZTE Corp.
Nanjing
China
Phone: +86 18061680168
Email: xiao.min2@zte.com.cn
Zheng(Sandy) Zhang
ZTE Corp.
Nanjing
China
Email: zhang.zheng@zte.com.cn
Weiqiang Cheng
China Mobile
Beijing
China
Email: chengweiqiang@chinamobile.com
Min, et al. Expires 31 July 2024 [Page 7]
