YANG Notification Transport Capabilities
draft-ietf-netconf-yp-transport-capabilities-05

NETCONF Working Group                                              Q. Wu
Internet-Draft                                                     Q. Ma
Intended status: Standards Track                                  Huawei
Expires: 18 December 2025                                  A. Huang-Feng
                                                               INSA-Lyon
                                                                 T. Graf
                                                                Swisscom
                                                            16 June 2025

                YANG Notification Transport Capabilities
            draft-ietf-netconf-yp-transport-capabilities-05

Abstract

   This document specifies a YANG module for YANG notifications
   transport capabilities which augments the notification capabilities
   model.  The module provides transport protocol, transport encoding,
   and transport encryption system capabilities for transport-specific
   notification.  This YANG module can be used by the client to learn
   capability information from the server at runtime or at
   implementation time, by making use of the YANG instance data file
   format.

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 18 December 2025.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   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
   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 . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Capabilities for Systems and Datastore Update
           Notifications . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   4
   3.  YANG Module . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Updates to the IETF XML Registry  . . . . . . . . . . . .   7
     4.2.  Updates to the YANG Module Names Registry . . . . . . . .   7
   5.  Implementation Status . . . . . . . . . . . . . . . . . . . .   8
     5.1.  Huawei VRP  . . . . . . . . . . . . . . . . . . . . . . .   8
     5.2.  Cisco IOS XR  . . . . . . . . . . . . . . . . . . . . . .   8
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   7.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .   8
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   9
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   9
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  11
   Appendix A.  Usage Example of interaction with UDP-Notif and
           HTTPS-Notif for Configured Subscription . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   The "ietf-system-capabilities" YANG module defined in [RFC9196]
   allows a client to discover a set of capabilities supported by a
   server (including, basic system capabilities and YANG-Push related
   capabilities) both at implementation time and at runtime.  These
   capabilities allow a client to adjust its behavior to take advantage
   of the features exposed by the server.

   However, clients and servers may still support various different
   transport specific parameters (e.g., transport protocol, encoding
   format or encryption).  As described in Section 3.2 of [RFC8641].  A
   simple negotiation (e.g., inserting hints into error responses to a
   failed RPC request) between subscribers and publishers for
   subscription parameters increases the likelihood of success for

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   subsequent RPC requests, but not guaranteed and widely supported,
   which may cause unexpected failure or additional message exchange
   between client and server.

   This document defines a more deterministic solution that relies upon
   a YANG module for YANG notifications transport capabilities that is
   built on top of [RFC9196].  The module can be used by a client to
   discover capability information from a server at runtime or at
   implementation time, by making use of the YANG instance data file
   format.

1.1.  Terminology

   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.

   The terms "subscriber", "publisher", and "receiver" are used as
   defined in [RFC8639].

   The terms "client", and "server" are used as defined in [RFC8342].

2.  Capabilities for Systems and Datastore Update Notifications

   Section 3.1 of [RFC8641] lists the server capabilities related to
   YANG-Push that are supported in the YANG module "ietf-notification-
   capabilities".

   These server capabilities are transport independent, session level
   capabilities.  They can be provided either at the implementation time
   or reported at runtime.

   This document provides additional transport related attributes
   associated with system capabilities:

   *  Specification of transport protocols that a client can request to
      establish an HTTPS-based [I-D.ietf-netconf-https-notif] or UDP-
      based [I-D.ietf-netconf-udp-notif] configured transport
      connection.

   *  Specification of transport encoding, including JSON or XML as
      defined in [RFC8040] or CBOR as defined in [RFC9254] the client
      can request to encode YANG notifications;

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   *  Specification of secure transport mechanisms that are needed by a
      client to communicate with a server including DTLS 1.2 [RFC6347],
      DTLS 1.3 [RFC9147], TLS 1.2 [RFC5246], TLS 1.3 [RFC8446].

   *  To that end, the model defined in this document augments the
      System Capabilities model[RFC9196].

2.1.  Tree Diagram

   The following tree diagram [RFC8340] provides an overview of the data
   model.

   module: ietf-yp-transport-capabilities

     augment /sysc:system-capabilities/notc:subscription-capabilities:
       +--ro transport-capabilities
          +--ro transport-capability* [transport-protocol]
             +--ro transport-protocol    identityref
             +--ro security-protocol*    union
             +--ro encoding-format*      identityref

3.  YANG Module

   <CODE BEGINS> file "ietf-yp-transport-capabilities@2025-06-07.yang"
   module ietf-yp-transport-capabilities {
     yang-version 1.1;
     namespace
       "urn:ietf:params:xml:ns:yang:ietf-yp-transport-capabilities";
     prefix ntc;

     import ietf-subscribed-notifications {
       prefix sn;
       reference
         "RFC 8639: Subscription to YANG Notifications";
     }
     import ietf-system-capabilities {
       prefix sysc;
       reference
         "RFC 9196: YANG Modules Describing Capabilities for
          Systems and Datastore Update Notifications";
     }
     import ietf-notification-capabilities {
       prefix notc;
       reference
         "RFC 9196: YANG Modules Describing Capabilities for
          Systems and Datastore Update Notifications";
     }
     import ietf-tls-common {

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       prefix tlscmn;
       reference
         "RFC 9645: YANG Groupings for TLS Clients and TLS Servers";
     }

     organization
       "IETF NETCONF (Network Configuration) Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/group/netconf/>
        WG List:  <mailto:netconf@ietf.org>

        Authors:  Qin Wu
                  <mailto:bill.wu@huawei.com>
                  Qiufang Ma
                  <mailto:maqiufang1@huawei.com>
                  Alex Huang Feng
                  <mailto:alex.huang-feng@insa-lyon.fr>
                  Thomas Graf
                  <mailto:thomas.graf@swisscom.com>";
     description
       "This module defines an extension to YANG-Push
        Notification Capabilities model that provides additional
        transport specific capabilities for YANG notifications.

        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) 2025 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
        Relating to IETF Documents
        (http://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 2025-06-07 {
       description
         "Initial revision.";
       reference

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         "RFC XXXX: YANG Notifications Transport Capabilities";
     }

     identity security-protocol {
       description
         "Identity for security protocols.";
     }

     identity dtls12 {
       base security-protocol;
       description
         "Indicates DTLS Protocol Version 1.2. DTLS 1.2 is obsolete,
          and thus it is NOT RECOMMENDED to enable this feature.";
       reference
         "RFC 6347: The Datagram Transport Layer Security (DTLS)
                    Protocol Version 1.2";
     }

     identity dtls13 {
       base security-protocol;
       description
         "Indicates DTLS Protocol Version 1.3.";
       reference
         "RFC 9147: The Datagram Transport Layer Security (DTLS)
                    Protocol Version 1.3";
     }

     augment "/sysc:system-capabilities"
           + "/notc:subscription-capabilities" {
       description
         "Adds system level capabilities.";
       container transport-capabilities {
         description
           "Specifies capabilities related to YANG-Push transports.";
         list transport-capability {
           key "transport-protocol";
           description
             "Indicates a list of capabilities related to notification
                     transport.";
           leaf transport-protocol {
             type identityref {
               base sn:transport;
             }
             description
               "Indicates supported transport protocol for YANG-Push.";
           }
           leaf-list security-protocol {
             type union {

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               type identityref {
                 base security-protocol;
               }
               type identityref {
                 base tlscmn:tls-version-base;
               }
             }
             description
               "Indicates transport security protocol.";
           }
           leaf-list encoding-format {
             type identityref {
               base sn:encoding;
             }
             description
               "Indicates supported encoding formats.";
           }
         }
       }
     }
   }
   <CODE ENDS>

4.  IANA Considerations

4.1.  Updates to the IETF XML Registry

   This document registers a URI in the "IETF XML Registry" [RFC3688].
   Following the format in [RFC3688], the following registration has
   been made:

   URI: urn:ietf:params:xml:ns:yang:ietf-yp-transport-capabilities
   Registrant Contact: The IESG.
   XML: N/A; the requested URI is an XML namespace.
   Reference: RFC XXXX (RFC Ed.: replace XXX with actual RFC number
     and remove this note.)

4.2.  Updates to the YANG Module Names Registry

   This document registers one YANG module in the "YANG Module Names"
   registry [RFC6020].  Following the format in [RFC6020], the following
   registration has been made:

   name: ietf-yp-transport-capabilities
   namespace: urn:ietf:params:xml:ns:yang:ietf-yp-transport-capabilities
   prefix: ntc
   reference: RFC XXXX (RFC Ed.: replace XXX with actual RFC number
     and remove this note.)

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5.  Implementation Status

   Note to the RFC-Editor: Please remove this section before publishing.

5.1.  Huawei VRP

   Huawei implemented this document for a YANG Push publisher in their
   VRP platform.

5.2.  Cisco IOS XR

   Cisco implemented this document for a YANG Push publisher in their
   IOS XR platform.

6.  Security Considerations

   This section is modeled after the template described in Section 3.7
   of [I-D.ietf-netmod-rfc8407bis]

   The "ietf-yp-transport-capabilities" 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 protocols
   have to use a secure transport layer (e.g., SSH [RFC4252], TLS
   [RFC8446], and QUIC [RFC9000]) and 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.

   All protocol-accessible data nodes are read-only and cannot be
   modified.  The data in the module is not security sensitive.  It
   inherits all the security considerations of [RFC9196].

7.  Contributors

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      Ran Tao
      Huawei
      101 Software Avenue, Yuhua District
      Nanjing, Jiangsu 210012
      China
      Email: taoran20@huawei.com

      Liang Geng
      China Mobile
      32 Xuanwumen West St, Xicheng District
      Beijing 10053
      China
      Email: gengliang@chinamobile.com

      Peng Liu
      China Mobile
      Beiqijia Town, Changping District
      Beijing 10053
      China
      Email: liupengyjy@chinamobile.com

      Wei Wang
      China Telecom
      32 Xuanwumen West St, Xicheng District
      Beijing 102209
      China
      Email: wangw36@chinatelecom.cn

8.  Acknowledgements

   The authors would like to thank Mohamed Boucadair, Kent Watson, Jan
   Lindblad, Reshad Rahman, Xiao Min, Per Andersson and Rob Wilton for
   their review and valuable comments.

9.  References

9.1.  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,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246,
              DOI 10.17487/RFC5246, August 2008,
              <https://www.rfc-editor.org/info/rfc5246>.

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   [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,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6347]  Rescorla, E. and N. Modadugu, "Datagram Transport Layer
              Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
              January 2012, <https://www.rfc-editor.org/info/rfc6347>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [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>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8639]  Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
              E., and A. Tripathy, "Subscription to YANG Notifications",
              RFC 8639, DOI 10.17487/RFC8639, September 2019,
              <https://www.rfc-editor.org/info/rfc8639>.

   [RFC8641]  Clemm, A. and E. Voit, "Subscription to YANG Notifications
              for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
              September 2019, <https://www.rfc-editor.org/info/rfc8641>.

   [RFC9147]  Rescorla, E., Tschofenig, H., and N. Modadugu, "The
              Datagram Transport Layer Security (DTLS) Protocol Version
              1.3", RFC 9147, DOI 10.17487/RFC9147, April 2022,
              <https://www.rfc-editor.org/info/rfc9147>.

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   [RFC9196]  Lengyel, B., Clemm, A., and B. Claise, "YANG Modules
              Describing Capabilities for Systems and Datastore Update
              Notifications", RFC 9196, DOI 10.17487/RFC9196, February
              2022, <https://www.rfc-editor.org/info/rfc9196>.

   [RFC9254]  Veillette, M., Ed., Petrov, I., Ed., Pelov, A., Bormann,
              C., and M. Richardson, "Encoding of Data Modeled with YANG
              in the Concise Binary Object Representation (CBOR)",
              RFC 9254, DOI 10.17487/RFC9254, July 2022,
              <https://www.rfc-editor.org/info/rfc9254>.

9.2.  Informative References

   [I-D.ietf-netconf-https-notif]
              Jethanandani, M. and K. Watsen, "An HTTPS-based Transport
              for YANG Notifications", Work in Progress, Internet-Draft,
              draft-ietf-netconf-https-notif-15, 1 February 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
              https-notif-15>.

   [I-D.ietf-netconf-udp-notif]
              Feng, A. H., Francois, P., Zhou, T., Graf, T., and P.
              Lucente, "UDP-based Transport for Configured
              Subscriptions", Work in Progress, Internet-Draft, draft-
              ietf-netconf-udp-notif-21, 14 May 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
              udp-notif-21>.

   [I-D.ietf-netmod-rfc8407bis]
              Bierman, A., Boucadair, M., and Q. Wu, "Guidelines for
              Authors and Reviewers of Documents Containing YANG Data
              Models", Work in Progress, Internet-Draft, draft-ietf-
              netmod-rfc8407bis-28, 5 June 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
              rfc8407bis-28>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC4252]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
              January 2006, <https://www.rfc-editor.org/info/rfc4252>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

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   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC9000]  Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
              Multiplexed and Secure Transport", RFC 9000,
              DOI 10.17487/RFC9000, May 2021,
              <https://www.rfc-editor.org/info/rfc9000>.

Appendix A.  Usage Example of interaction with UDP-Notif and HTTPS-Notif
             for Configured Subscription

   The following instance-data example describes the notification
   transport capabilities of a hypothetical "acme-router".

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   ================= NOTE: '\' line wrapping per RFC 8792 ==================

   <?xml version="1.0" encoding="UTF-8"?>
   <instance-data-set
     xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-instance-data"
     xmlns:hnt="urn:ietf:params:xml:ns:yang:ietf-https-notif-transport"
     xmlns:sn="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
     xmlns:tlscmn="urn:ietf:params:xml:ns:yang:ietf-tls-common"
     xmlns:tlscmn="urn:ietf:params:xml:ns:yang:ietf-tls-common"
     xmlns:unt="urn:ietf:params:xml:ns:yang:ietf-udp-notif-transport">
     <name>acme-router-notification-capabilities</name>
     <content-schema>
       <module>ietf-system-capabilities@2020-03-23</module>
       <module>ietf-notification-capabilities@2020-03-23</module>
       <module>ietf-yp-transport-capabilities@2025-06-07</module>
     </content-schema>
     <!-- revision date, contact, etc. -->
     <description>Server Capability Discovery</description>
     <content-data>
       <system-capabilities xmlns="urn:ietf:params:xml:ns:yang:ietf-system-\
         capabilities">
         <subscription-capabilities xmlns="urn:ietf:params:xml:ns:yang:ietf\
           -notification-capabilities">
           <transport-capabilities xmlns="urn:ietf:params:xml:ns:yang:ietf-\
             yp-transport-capabilities">
             <transport-capability>
               <transport-protocol>hnt:https</transport-protocol>
               <encoding-format>sn:encode-xml</encoding-format>
               <encoding-format>sn:encode-json</encoding-format>
               <security-protocol>tlscmn:tls12</security-protocol>
               <security-protocol>tlscmn:tls13</security-protocol>
             </transport-capability>
             <transport-capability>
               <transport-protocol>unt:udp-notif</transport-protocol>
               <encoding-format>sn:encode-json</encoding-format>
               <encoding-format>unt:encode-cbor</encoding-format>
               <security-protocol>dtls12</security-protocol>
               <security-protocol>dtls13</security-protocol>
             </transport-capability>
           </transport-capabilities>
         </subscription-capabilities>
       </system-capabilities>
     </content-data>
   </instance-data-set>

   In addition, the client could also query notification transport
   capabilities from the server.  For example, the client sends <get>
   request message to the the server to query from the server.

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   ================= NOTE: '\' line wrapping per RFC 8792 ==================

   <rpc message-id="101"
     xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
     <get>
       <filter type="subtree">
         <system-capabilities xmlns="urn:ietf:params:xml:ns:yang:ietf-syste\
           m-capabilities">
           <subscription-capabilities xmlns="urn:ietf:params:xml:ns:yang:ie\
             tf-notification-capabilities">
             <transport-capabilities xmlns="urn:ietf:params:xml:ns:yang:iet\
               f-yp-transport-capabilities"/>
           </subscription-capabilities>
         </system-capabilities>
       </filter>
     </get>
   </rpc>

   The server returns server data export capability using <rpc-reply> as
   follows:

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   ================= NOTE: '\' line wrapping per RFC 8792 ==================

   <rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
     xmlns:sc="urn:ietf:params:xml:ns:yang:ietf-system-capabilities"
     xmlns:nc="urn:ietf:params:xml:ns:yang:ietf-notification-capabilities"
     xmlns:tc="urn:ietf:params:xml:ns:yang:ietf-yp-transport-capabilities"
     xmlns:hnt="urn:ietf:params:xml:ns:yang:ietf-https-notif-transport"
     xmlns:sn="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
     xmlns:unt="urn:ietf:params:xml:ns:yang:ietf-udp-notif-transport"
     xmlns:tlscmn="urn:ietf:params:xml:ns:yang:ietf-tls-common" message-id=\
     "101">
     <data>
       <sc:system-capabilities>
         <nc:subscription-capabilities>
           <transport-capabilities xmlns="urn:ietf:params:xml:ns:yang:ietf-\
             yp-transport-capabilities">
             <transport-capability>
               <transport-protocol>hnt:https</transport-protocol>
               <encoding-format>sn:encode-xml</encoding-format>
               <encoding-format>sn:encode-json</encoding-format>
               <security-protocol>tlscmn:tls12</security-protocol>
               <security-protocol>tlscmn:tls13</security-protocol>
             </transport-capability>
             <transport-capability>
               <transport-protocol>unt:udp-notif</transport-protocol>
               <encoding-format>sn:encode-json</encoding-format>
               <encoding-format>unt:encode-cbor</encoding-format>
               <security-protocol>dtls12</security-protocol>
               <security-protocol>dtls13</security-protocol>
             </transport-capability>
           </transport-capabilities>
         </nc:subscription-capabilities>
       </sc:system-capabilities>
     </data>
   </rpc-reply>

Authors' Addresses

   Qin Wu
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing
   Jiangsu, 210012
   China
   Email: bill.wu@huawei.com

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   Qiufang Ma
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing
   Jiangsu, 210012
   China
   Email: maqiufang1@huawei.com

   Alex Huang Feng
   INSA-Lyon
   Lyon
   France
   Email: alex.huang-feng@insa-lyon.fr

   Thomas Graf
   Swisscom
   Binzring 17
   CH-8045 Zurich
   Switzerland
   Email: thomas.graf@swisscom.com

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