IPPM T. Graf Internet-Draft Swisscom Intended status: Standards Track M. Wang Expires: 13 December 2026 China Mobile G. Fioccola T. Zhou Huawei X. Min ZTE Corporation 11 June 2026 A YANG Data Model for the Alternate Marking Method draft-ietf-ippm-alt-mark-yang-03 Abstract Alternate-Marking Method is a technique used to perform packet loss, delay, and jitter measurements on in-flight packets. This document defines a YANG data model for the Alternate Marking Method. 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 13 December 2026. Copyright Notice Copyright (c) 2026 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 Graf, et al. Expires 13 December 2026 [Page 1] Internet-Draft yang-alternate-marking June 2026 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. Requirements Language . . . . . . . . . . . . . . . . . . 2 1.2. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3 2. AltMark Tree Diagram . . . . . . . . . . . . . . . . . . . . 3 3. AltMark Profile . . . . . . . . . . . . . . . . . . . . . . . 5 4. Alternate Marking Method YANG Data Model . . . . . . . . . . 5 5. Operational Considerations . . . . . . . . . . . . . . . . . 15 6. Security Considerations . . . . . . . . . . . . . . . . . . . 15 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 16 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 10.1. Normative References . . . . . . . . . . . . . . . . . . 17 10.2. Informative References . . . . . . . . . . . . . . . . . 18 Appendix A. Example . . . . . . . . . . . . . . . . . . . . . . 20 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 1. Introduction Alternate-Marking Method [RFC9341] [RFC9342] (AltMark) is a technique used to perform packet loss, delay, and jitter measurements on in- flight packets. This document defines a YANG data model for the Alternate Marking Method. The YANG data model introduced in this document can be used For configuration, while [I-D.ietf-ippm-on-path-telemetry-yang] defines the YANG data model for monitoring on-path telemetry data, including AltMark telemetry data. Section 2 includes the tree diagram, while Section 4 includes the data model. Also, an example is reported in Appendix A. 1.1. 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. Graf, et al. Expires 13 December 2026 [Page 2] Internet-Draft yang-alternate-marking June 2026 1.2. Conventions The following terms are defined in [RFC7950] and are used in this specification: * augment * data model * data node The terminology for describing YANG data models is found in [RFC7950]. 2. AltMark Tree Diagram Tree diagrams used in this document follow the notation defined in [RFC8340]. The AltMark model is organized as shown in the following figure. Each AltMark profile associates with one flow and the corresponding AltMark information. The "altmark-info" is a container for all the read only information that assists monitoring systems in the interpretation of the AltMark data. Graf, et al. Expires 13 December 2026 [Page 3] Internet-Draft yang-alternate-marking June 2026 module: ietf-altmark +--rw altmark +--rw admin-config | +--rw enabled? boolean +--rw available-interfaces +--rw available-interface* [if-name] +--rw if-name if:interface-ref +--rw altmark-profiles +--rw altmark-profile* [altmark-profile-name] +--rw altmark-profile-name string +--rw filter | +--rw filter-type? altmark-filter-type | +--rw ace-name? -> /acl:acls/acl/aces/ace/name +--rw direction flow-direction +--rw interface-action altmark-interface-action +--rw protocol-type? altmark-protocol-type +--rw flow-mon-id? flow-id +--rw method-type? altmark-method-type +--rw measurement-period? uint64 +--rw measurement-mode? altmark-measurement-mode +--rw enable-loss-measurement? boolean +--rw enable-delay-measurement? boolean In the "altmark-profiles", the "enabled" is an administrative configuration. When set to true, AltMark configuration is enabled for the system. Meanwhile, the AltMark data-plane functionality is enabled. The "filter" is used to identify a flow, where the AltMark data can be applied. There may be multiple filter types. ACL [RFC8519] is a common way to specify a flow. The AltMark profile can associate with an ACE(Access Control Entry). AltMark actions MUST be driven by the accepted packets, when the matched ACE "forwarding" action is "accept". The AltMark data can be encapsulated into multiple protocols, e.g., IPv6 [RFC9343], SRH [RFC9947], and MPLS [RFC9714]. Additional protocol extensions are reported in [I-D.ietf-ippm-alt-mark-deployment] The "protocol-type" is used to indicate the protocol for the AltMark application. For example, if the "protocol-type" is IPv6, the AltMark marking node will encapsulate the associated flow with the IPv6 [RFC9343] format. Graf, et al. Expires 13 December 2026 [Page 4] Internet-Draft yang-alternate-marking June 2026 3. AltMark Profile The AltMark data is expected to be read and exported or locally aggregated at every interface that the flow traverses within the AltMark domain. The "altmark-profile" contains the detailed information for the AltMark data. The information includes: * altmark-profile-name: it is the unique identifier for each AltMark profile. * filter: it is used to identify a flow, where the AltMark data can be applied. * direction: it is used to indicate the direction of the flow: ingress, transit, egress. * interface-action: indicates the operation applied to the flow (e.g. marking AltMark header, read the AltMark data, or unmarking AltMark header). * protocol-type: it is used to indicate the protocol for the AltMark application. * flow-mon-id: it is used to identify the monitored flow and to correlate the exported data of the same flow from multiple nodes and from multiple packets. It is defined in [RFC9343] for IPv6, in [RFC9947] for SRH and in [RFC9714] for MPLS. Note that it corresponds to the altmarkFlowMonID parameter defined in [I-D.ietf-opsawg-ipfix-alt-mark]. * method-type: it is used to indicate the type of the method: single marking, double marking. * measurement-period: it indicates the AltMark period (see [I-D.ietf-ippm-alt-mark-deployment]). * measurement-mode: it specifies the measurement mode: hop-by-hop or end-to-end. * enable-loss-measurement: if true, it enables loss measurements. * enable-delay-measurement: if true, it enables delay measurements. 4. Alternate Marking Method YANG Data Model Graf, et al. Expires 13 December 2026 [Page 5] Internet-Draft yang-alternate-marking June 2026 file "ietf-altmark@2026-06-11.yang" module ietf-altmark { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-altmark"; prefix "altmark"; import ietf-access-control-list { prefix "acl"; reference "RFC 8519: YANG Data Model for Network Access Control Lists (ACLs)"; } import ietf-interfaces { prefix "if"; reference "RFC 8343: A YANG Data Model for Interface Management"; } organization "IETF IPPM (IP Performance Metrics) Working Group"; contact "WG Web: WG List: Author: thomas.graf@swisscom.com Author: wangminxue@chinamobile.com Author: giuseppe.fioccola@huawei.com Author: zhoutianran@huawei.com Author: xiao.min2@zte.com.cn"; description "This YANG module specifies a vendor-independent data model for the Alternate Marking (AltMark). 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. Copyright (c) 2026 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Graf, et al. Expires 13 December 2026 [Page 6] Internet-Draft yang-alternate-marking June 2026 Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself for full legal notices."; revision 2026-06-11 { description "First revision."; reference "RFC XXXX: A YANG Data Model for Alternate-Marking"; } /* * FEATURES */ feature altmark { description "This feature indicated that the Alternate-Marking Method is supported."; reference "RFC 9341: Alternate-Marking Method; RFC 9342: Clustered Alternate-Marking Method RFC 9343: IPv6 Application of the Alternate-Marking Method RFC 9714: Application of the Alternate Marking Method to the MPLS Label Stack RFC 9947: Application of the Alternate Marking Method to the Segment Routing Header"; } /* * IDENTITIES */ identity filter { description "Base identity to represent a filter. A filter is used to specify the flow to which the AltMark method is applied."; } identity acl-filter { base filter; description "Apply ACL rules to specify the flow."; } identity method { description Graf, et al. Expires 13 December 2026 [Page 7] Internet-Draft yang-alternate-marking June 2026 "Base identity to represent the method type."; } identity single-marking { base method; description "The AltMark Single-Marking method."; } identity double-marking { base method; description "The AltMark Double-Marking method."; } identity protocol { description "Base identity to represent the protocol. It's used to indicate the protocol for the application of the AltMark method."; } identity ipv6 { base protocol; description "The AltMark method is applied to IPv6 protocol."; reference "RFC 9343: IPv6 Application of the Alternate-Marking Method"; } identity srh { base protocol; description "The AltMark method is applied to SRH."; reference "RFC 9947: Application of the Alternate Marking Method to the Segment Routing Header"; } identity mpls { base protocol; description "The AltMark method is applied to MPLS."; reference "RFC 9714: Application of the Alternate Marking Method to the MPLS Label Stack"; } Graf, et al. Expires 13 December 2026 [Page 8] Internet-Draft yang-alternate-marking June 2026 identity interface-action { description "Base identity to represent the interface actions. It's used to indicate what action the node will take on that interface."; } identity action-marking { base interface-action; description "It indicates that the interface must mark the AltMark data field, according to the operations described in RFC 9341 and RFC 9342"; } identity action-unmarking { base interface-action; description "It indicates that the interface must unmark the AltMark data field, according to the operations described in RFC 9341 and RFC 9342"; } identity action-read { base interface-action; description "It indicates that the interface only reads the AltMark data, according to the operations described in RFC 9341 and RFC 9342"; } /* * TYPE DEFINITIONS */ typedef altmark-filter-type { type identityref { base filter; } description "It specifies a known type of filter."; } typedef altmark-interface-action { type identityref { base interface-action; } description "It specifies the action on the interface."; Graf, et al. Expires 13 December 2026 [Page 9] Internet-Draft yang-alternate-marking June 2026 } typedef altmark-method-type { type identityref { base method; } description "It specifies the AltMark method used."; } typedef altmark-protocol-type { type identityref { base protocol; } description "It specifies a known type of carrier protocol for the AltMark data."; } typedef flow-id { type uint32 { range 0..1048575; } description "It specifies the 20-bit AltMark flow identifier."; } typedef flow-direction { type enumeration { enum "ingress" { value 1; description "Ingress of an AltMark flow."; } enum "transit" { value 2; description "Transit of an AltMark flow."; } enum "egress" { value 3; description "Egress of an AltMark flow."; } } description "Flow direction."; } Graf, et al. Expires 13 December 2026 [Page 10] Internet-Draft yang-alternate-marking June 2026 typedef altmark-measurement-mode { type enumeration { enum "e2e" { value 1; description "It indicates that end-to-end measurements can be enabled."; } enum "hbh" { value 2; description "It indicates that hop-by-hop measurements can be enabled."; } } description "It specifies the measurement mode."; } /* * GROUP DEFINITIONS */ grouping altmark-admin-config { description "AltMark top-level administrative configuration."; leaf enabled { type boolean; default false; description "This object is to control the availability of configuration. It MUST be true before anything in the /altmark/altmark-profile can be edited. If false, any configuration in place is not used."; } } grouping altmark-filter { description "A grouping for AltMark filter definition"; leaf filter-type { type altmark-filter-type; description "filter type"; } leaf ace-name { when "derived-from-or-self(../filter-type, 'altmark:acl-filter')"; Graf, et al. Expires 13 December 2026 [Page 11] Internet-Draft yang-alternate-marking June 2026 type leafref { path "/acl:acls/acl:acl/acl:aces/acl:ace/acl:name"; } description "The Access Control Entry name is used to refer to an ACL specification."; } } grouping altmark-setup { description "A grouping for AltMark profile."; leaf flow-mon-id { type flow-id; description "It specifies the FlowMonID. A 20-bit flow identifier as defined in RFC 9343 and RFC 9714. The field is set at the marking node. The FlowMonID can be uniformly assigned by a central controller or algorithmically generated by the marking node. Note that it corresponds to the altmarkFlowMonID parameter defined in draft-ietf-opsawg-ipfix-alt-mark."; } leaf method-type { type altmark-method-type; description "This item is used to indicate the AltMark method."; } leaf measurement-period { type uint64; description "It specifies the AltMark marking period. Its value can be set according to RFC 9341, RFC 9342 and draft-ietf-ippm-alt-mark-deployment"; } leaf measurement-mode { type altmark-measurement-mode; default "hbh"; description "It specifies the AltMark measurement mode."; } } /* Graf, et al. Expires 13 December 2026 [Page 12] Internet-Draft yang-alternate-marking June 2026 * DATA NODES */ container altmark { description "AltMark top level container"; container admin-config { description "Contains all the administrative configurations related to the AltMark functionalities"; uses altmark-admin-config; } container available-interfaces { description "It contains the list of the interfaces to be activated for AltMark"; list available-interface { key "if-name"; description "A list of available interfaces that support Alternate-Marking."; leaf if-name { type if:interface-ref; description "This is a reference to the Interface name."; } container altmark-profiles { description "Contains the AltMark profiles."; list altmark-profile { if-feature altmark; key "altmark-profile-name"; description "It describes the list of the AltMark profiles configured on the node. The AltMark feature MUST be enabled on the node before anything in the altmark-profile can be edited"; leaf altmark-profile-name { type string{ length "1..300"; } description "Unique identifier for each AltMark profile."; Graf, et al. Expires 13 December 2026 [Page 13] Internet-Draft yang-alternate-marking June 2026 } container filter { uses altmark-filter; description "The filter which is used to indicate the flow where the AltMark is applied."; } leaf direction { type flow-direction; description "Specify the flow direction."; } leaf interface-action { type altmark-interface-action; default action-read; description "This object indicates the action that the node needs to take, i.e. marking/read/unmarking."; } leaf protocol-type { type altmark-protocol-type; description "This item is used to indicate the carrier protocol where the AltMark is applied."; } uses altmark-setup; leaf enable-loss-measurement { type boolean; default false; description "If true, it indicates that loss measurements are enabled."; } leaf enable-delay-measurement { type boolean; default false; description "If true, it indicates that delay measurements are enabled."; } } Graf, et al. Expires 13 December 2026 [Page 14] Internet-Draft yang-alternate-marking June 2026 } } } } } 5. Operational Considerations The operational and management considerations for the Alternate Marking Method are covered in [I-D.ietf-ippm-alt-mark-deployment], Alternate Marking [RFC9341] and Multipoint Alternate Marking [RFC9342]. Further details about the method operation are specified for the different extensions: IPv6 [RFC9343], SRH [RFC9947], and MPLS [RFC9714]. 6. Security Considerations The "ietf-altmark" YANG module defines a data model that is designed to be accessed via YANG-based management protocols, such as NETCONF [RFC6241] and RESTCONF [RFC8040]. These YANG-based management protocols (1) have to use a secure transport layer (e.g., Secure Shell (SSH) [RFC4252], TLS [RFC8446], and QUIC [RFC9000]) and (2) have to use mutual authentication. The Network Configuration Access Control Model (NACM) [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., "config true", which is the default). All writable data nodes are likely to be sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) and delete operations to these data nodes without proper protection or authentication can have a negative effect on network operations. The following subtrees and data nodes have particular sensitivities/vulnerabilities: * /altmark/admin-config The items in the container above include the top level administrative configurations related to the AltMark functionalities. Unexpected changes to these items could lead to the AltMark function disruption and/ or misbehavior of the AltMark. Graf, et al. Expires 13 December 2026 [Page 15] Internet-Draft yang-alternate-marking June 2026 * /altmark/available-interfaces/available-interface/altmark- profiles/altmark-profile The entries in the container above include the AltMark profile configurations which indirectly create or modify the device configurations. Unexpected changes to these entries could lead to the mistake of the AltMark behavior for the corresponding flows. Alternate Marking [RFC9341] and Multipoint Alternate Marking [RFC9342] analyze different security concerns and related solutions. These aspects are valid and applicable also to this document. In particular the fundamental security requirement is that Alternate Marking MUST only be applied in a specific limited domain, as also mentioned in [RFC8799]. 7. IANA Considerations IANA is requested to register the following URI in the "ns" registry within the IETF XML Registry [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-altmark Registrant Contact: The IESG XML: N/A; the requested URI is an XML namespace. IANA is requested to register the following YANG module in the "YANG Module Names" registry [RFC6020] within the "YANG Parameters" registry group: Name: ietf-altmark Maintained by IANA? N Namespace: urn:ietf:params:xml:ns:yang:ietf-altmark Prefix: altmark Reference: RFC XXXX 8. Acknowledgements The authors would like to thank Alex Huang Feng, Benoit Claise, Acee Lindem for the precious comments and suggestions. 9. Contributors Jun Guo ZTE Corporation Nanjing China Email: guo.jun2@zte.com.cn Graf, et al. Expires 13 December 2026 [Page 16] Internet-Draft yang-alternate-marking June 2026 Fabio Bulgarella Telecom Italia Via Reiss Romoli, 274 10148 Torino Italy Email: fabio.bulgarella@guest.telecomitalia.it Massimo Nilo Telecom Italia Via Reiss Romoli, 274 10148 Torino Italy Email: massimo.nilo@telecomitalia.it Liuyan Han China Mobile No.32 Xuanwumen west street Beijing 100053 China Email: hanliuyan@chinamobile.com 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . Graf, et al. Expires 13 December 2026 [Page 17] Internet-Draft yang-alternate-marking June 2026 [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC9341] Fioccola, G., Ed., Cociglio, M., Mirsky, G., Mizrahi, T., and T. Zhou, "Alternate-Marking Method", RFC 9341, DOI 10.17487/RFC9341, December 2022, . [RFC9342] Fioccola, G., Ed., Cociglio, M., Sapio, A., Sisto, R., and T. Zhou, "Clustered Alternate-Marking Method", RFC 9342, DOI 10.17487/RFC9342, December 2022, . [RFC9343] Fioccola, G., Zhou, T., Cociglio, M., Qin, F., and R. Pang, "IPv6 Application of the Alternate-Marking Method", RFC 9343, DOI 10.17487/RFC9343, December 2022, . [RFC9714] Cheng, W., Ed., Min, X., Ed., Zhou, T., Dai, J., and Y. Peleg, "Encapsulation for MPLS Performance Measurement with the Alternate-Marking Method", RFC 9714, DOI 10.17487/RFC9714, February 2025, . 10.2. Informative References [I-D.ietf-ippm-alt-mark-deployment] Fioccola, G., Zhu, K., Graf, T., Zhang, L., and M. Nilo, "Alternate Marking Deployment Framework", Work in Progress, Internet-Draft, draft-ietf-ippm-alt-mark- deployment-05, 25 February 2026, . Graf, et al. Expires 13 December 2026 [Page 18] Internet-Draft yang-alternate-marking June 2026 [I-D.ietf-ippm-on-path-telemetry-yang] Fioccola, G., Zhou, T., Zhu, Y., Zhang, W., and K. Zhu, "On-Path Telemetry YANG Data Model", Work in Progress, Internet-Draft, draft-ietf-ippm-on-path-telemetry-yang-02, 2 January 2026, . [I-D.ietf-opsawg-ipfix-alt-mark] Graf, T., Fioccola, G., Zhou, T., and Y. Zhu, "IP Flow Information Export (IPFIX) Alternate-Marking Information Elements", Work in Progress, Internet-Draft, draft-ietf- opsawg-ipfix-alt-mark-05, 27 February 2026, . [RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH) Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252, January 2006, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . [RFC8519] Jethanandani, M., Agarwal, S., Huang, L., and D. Blair, "YANG Data Model for Network Access Control Lists (ACLs)", RFC 8519, DOI 10.17487/RFC8519, March 2019, . [RFC8799] Carpenter, B. and B. Liu, "Limited Domains and Internet Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020, . [RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based Multiplexed and Secure Transport", RFC 9000, DOI 10.17487/RFC9000, May 2021, . Graf, et al. Expires 13 December 2026 [Page 19] Internet-Draft yang-alternate-marking June 2026 [RFC9947] Fioccola, G., Zhou, T., Mishra, G., Wang, X., Zhang, G., and M. Cociglio, "Application of the Alternate-Marking Method to the Segment Routing Header", RFC 9947, DOI 10.17487/RFC9947, March 2026, . Appendix A. Example An example of the Alternate-Marking Profile is reported in the following figure. This configuration is received by an AltMark marking node. This node adds the AltMark IPv6 extension header to enable the method. Graf, et al. Expires 13 December 2026 [Page 20] Internet-Draft yang-alternate-marking June 2026 true gigabitethernet-1/0 ietf-test-profile acl-filter test-acl action-marking ipv6 1 double-marking 10 hbh-measurement true true Authors' Addresses Thomas Graf Swisscom Binzring 17 CH-8045 Zurich Switzerland Email: thomas.graf@swisscom.com Graf, et al. Expires 13 December 2026 [Page 21] Internet-Draft yang-alternate-marking June 2026 Minxue Wang China Mobile No.32 Xuanwumen west street Beijing 100053 China Email: wangminxue@chinamobile.com Giuseppe Fioccola Huawei Viale Martesana, 12 20055 Vimodrone (Milan) Italy Email: giuseppe.fioccola@huawei.com Tianran Zhou Huawei 156 Beiqing Rd. Beijing 100095 China Email: zhoutianran@huawei.com Xiao Min ZTE Corporation Nanjing China Email: xiao.min2@zte.com.cn Graf, et al. Expires 13 December 2026 [Page 22]