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DOTS                                                        M. Boucadair
Internet-Draft                                                    Orange
Updates: 8782 (if approved)                                   J. Shallow
Intended status: Standards Track                            July 6, 2020
Expires: January 7, 2021


    A YANG Data Model for Distributed Denial-of-Service Open Threat
                    Signaling (DOTS) Signal Channel
              draft-boucadair-dots-rfc8782-yang-update-00

Abstract

   This document specifies an updated version of the Distributed Denial-
   of-Service Open Threat Signaling (DOTS) Signal Channel YANG data
   model.  This updated version makes use of the new mechanisms for
   defining abstract data structures with YANG as specified in RFC8791.

   This document updates RFC 8782.

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 January 7, 2021.

Copyright Notice

   Copyright (c) 2020 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 extracted from this document must



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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Summary of Changes From RFC8782 . . . . . . . . . . . . . . .   2
   3.  Tree Structure  . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  YANG Module . . . . . . . . . . . . . . . . . . . . . . . . .   6
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  18
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  19
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  19
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  19
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  19
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  20
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  20

1.  Introduction

   As specified in [RFC8782], messages exchanged between DOTS agents are
   serialized using Concise Binary Object Representation (CBOR)
   [RFC7252].  CBOR-encoded payloads are used to carry signal channel-
   specific payload messages which convey request parameters and
   response information such as errors.

   This document specifies a YANG module [RFC7950] for representing DOTS
   mitigation scopes, DOTS signal channel session configuration data,
   and DOTS redirected signaling.  All parameters in the payload of the
   DOTS signal channel are mapped to CBOR types as specified in Table 5
   of [RFC8782].

   This YANG module is not intended to be used via NETCONF/RESTCONF for
   DOTS server management purposes; such a module is out of the scope of
   this document.  It serves only to provide abstract data structures.
   This document uses the "structure" extension specified in [RFC8791].

   The meaning of the symbols in YANG tree diagrams is defined in
   [RFC8340] and [RFC8791].

2.  Summary of Changes From RFC8782

   The main changes compared to the YANG version published in [RFC8782]
   are as follows:

   o  Follow the new YANG data structure specified in [RFC8791].





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   o  Add in "choice" to indicate the communication direction in which a
      data node applies.  If no "choice" is indicated, a node can appear
      in both directions (i.e., from DOTS clients to DOTS servers and
      vice versa).

   o  Remove "config" clauses.  Note that "config" statements will be
      ignored (if present) anyway according to Section 4 of [RFC8791].

   o  Remove "cuid", "cdid", and "sid" nodes from the structure because
      these nodes are included as Uri-Path options, not within the
      message body.

   o  Remove the list keys for the mitigation scope message type (i.e.,
      "cuid" and "mid"). "mid" is not indicated as a key because it is
      included as Uri-Path option for requests and in the message body
      for responses.  Note that Section 4 of [RFC8791] specifies that a
      list does not require to have a key statement defined.

   These changes are made with the constraint to avoid changes to the
   mapping table defined in Table 5 of [RFC8782].  A DOTS signal channel
   attribute that may be present in both requests and responses will
   thus have the same CBOR key value and CBOR major type.

3.  Tree Structure

   This document defines the YANG module "ietf-dots-signal-channel",
   which has the following tree structure.  A DOTS signal message can be
   a mitigation, a configuration, a redirect, or a heartbeat message.
   The use of these attributes is specified in [RFC8782].

   This tree structure obsoletes the one described in Section 5.1 of
   [RFC8782].

    module: ietf-dots-signal-channel

      structure dots-signal:
        +-- (message-type)?
           +--:(mitigation-scope)
           |  +-- scope* []
           |     +-- target-prefix*                inet:ip-prefix
           |     +-- target-port-range* [lower-port]
           |     |  +-- lower-port    inet:port-number
           |     |  +-- upper-port?   inet:port-number
           |     +-- target-protocol*              uint8
           |     +-- target-fqdn*                  inet:domain-name
           |     +-- target-uri*                   inet:uri
           |     +-- alias-name*                   string
           |     +-- lifetime?                     int32



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           |     +-- trigger-mitigation?           boolean
           |     +-- (direction)?
           |        +--:(server-to-client-only)
           |           +-- mid?                    uint32
           |           +-- mitigation-start?       uint64
           |           +-- status?                 iana-signal:status
           |           +-- conflict-information
           |           |  +-- conflict-status?
           |           |  |       iana-signal:conflict-status
           |           |  +-- conflict-cause?
           |           |  |       iana-signal:conflict-cause
           |           |  +-- retry-timer?       uint32
           |           |  +-- conflict-scope
           |           |     +-- target-prefix*       inet:ip-prefix
           |           |     +-- target-port-range* [lower-port]
           |           |     |  +-- lower-port    inet:port-number
           |           |     |  +-- upper-port?   inet:port-number
           |           |     +-- target-protocol*     uint8
           |           |     +-- target-fqdn*         inet:domain-name
           |           |     +-- target-uri*          inet:uri
           |           |     +-- alias-name*          string
           |           |     +-- acl-list* [acl-name]
           |           |     |  +-- acl-name    leafref
           |           |     |  +-- acl-type?   leafref
           |           |     +-- mid?                 uint32
           |           +-- bytes-dropped?
           |           |       yang:zero-based-counter64
           |           +-- bps-dropped?            yang:gauge64
           |           +-- pkts-dropped?
           |           |       yang:zero-based-counter64
           |           +-- pps-dropped?            yang:gauge64
           |           +-- attack-status?
           |                   iana-signal:attack-status
           +--:(signal-config)
           |  +-- mitigating-config
           |  |  +-- heartbeat-interval
           |  |  |  +-- (direction)?
           |  |  |  |  +--:(server-to-client-only)
           |  |  |  |     +-- max-value?   uint16
           |  |  |  |     +-- min-value?   uint16
           |  |  |  +-- current-value?     uint16
           |  |  +-- missing-hb-allowed
           |  |  |  +-- (direction)?
           |  |  |  |  +--:(server-to-client-only)
           |  |  |  |     +-- max-value?   uint16
           |  |  |  |     +-- min-value?   uint16
           |  |  |  +-- current-value?     uint16
           |  |  +-- probing-rate



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           |  |  |  +-- (direction)?
           |  |  |  |  +--:(server-to-client-only)
           |  |  |  |     +-- max-value?   uint16
           |  |  |  |     +-- min-value?   uint16
           |  |  |  +-- current-value?     uint16
           |  |  +-- max-retransmit
           |  |  |  +-- (direction)?
           |  |  |  |  +--:(server-to-client-only)
           |  |  |  |     +-- max-value?   uint16
           |  |  |  |     +-- min-value?   uint16
           |  |  |  +-- current-value?     uint16
           |  |  +-- ack-timeout
           |  |  |  +-- (direction)?
           |  |  |  |  +--:(server-to-client-only)
           |  |  |  |     +-- max-value-decimal?   decimal64
           |  |  |  |     +-- min-value-decimal?   decimal64
           |  |  |  +-- current-value-decimal?     decimal64
           |  |  +-- ack-random-factor
           |  |     +-- (direction)?
           |  |     |  +--:(server-to-client-only)
           |  |     |     +-- max-value-decimal?   decimal64
           |  |     |     +-- min-value-decimal?   decimal64
           |  |     +-- current-value-decimal?     decimal64
           |  +-- idle-config
           |     +-- heartbeat-interval
           |     |  +-- (direction)?
           |     |  |  +--:(server-to-client-only)
           |     |  |     +-- max-value?   uint16
           |     |  |     +-- min-value?   uint16
           |     |  +-- current-value?     uint16
           |     +-- missing-hb-allowed
           |     |  +-- (direction)?
           |     |  |  +--:(server-to-client-only)
           |     |  |     +-- max-value?   uint16
           |     |  |     +-- min-value?   uint16
           |     |  +-- current-value?     uint16
           |     +-- probing-rate
           |     |  +-- (direction)?
           |     |  |  +--:(server-to-client-only)
           |     |  |     +-- max-value?   uint16
           |     |  |     +-- min-value?   uint16
           |     |  +-- current-value?     uint16
           |     +-- max-retransmit
           |     |  +-- (direction)?
           |     |  |  +--:(server-to-client-only)
           |     |  |     +-- max-value?   uint16
           |     |  |     +-- min-value?   uint16
           |     |  +-- current-value?     uint16



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           |     +-- ack-timeout
           |     |  +-- (direction)?
           |     |  |  +--:(server-to-client-only)
           |     |  |     +-- max-value-decimal?   decimal64
           |     |  |     +-- min-value-decimal?   decimal64
           |     |  +-- current-value-decimal?     decimal64
           |     +-- ack-random-factor
           |        +-- (direction)?
           |        |  +--:(server-to-client-only)
           |        |     +-- max-value-decimal?   decimal64
           |        |     +-- min-value-decimal?   decimal64
           |        +-- current-value-decimal?     decimal64
           +--:(redirected-signal)
           |  +-- (direction)?
           |     +--:(server-to-client-only)
           |        +-- alt-server           string
           |        +-- alt-server-record*   inet:ip-address
           +--:(heartbeat)
              +-- peer-hb-status             boolean


4.  YANG Module

   This module uses the common YANG types defined in [RFC6991] and types
   defined in [RFC8783].

   This version obsoletes the version described in Section 5.3 of
   [RFC8782].

 <CODE BEGINS> file "ietf-dots-signal-channel@2020-07-02.yang"
 module ietf-dots-signal-channel {
   yang-version 1.1;
   namespace "urn:ietf:params:xml:ns:yang:ietf-dots-signal-channel";
   prefix signal;

   import ietf-inet-types {
     prefix inet;
     reference
       "Section 4 of RFC 6991";
   }
   import ietf-yang-types {
     prefix yang;
     reference
       "Section 3 of RFC 6991";
   }
   import ietf-dots-data-channel {
     prefix ietf-data;
     reference



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       "RFC 8783: Distributed Denial-of-Service Open Threat Signaling
                  (DOTS) Data Channel Specification";
   }
   import iana-dots-signal-channel {
     prefix iana-signal;
     reference
       "RFC 8782: Distributed Denial-of-Service Open Threat Signaling
                  (DOTS) Signal Channel Specification";
   }
   import ietf-yang-structure-ext {
     prefix sx;
     reference
       "RFC 8791: YANG Data Structure Extensions";
   }

   organization
     "IETF DDoS Open Threat Signaling (DOTS) Working Group";
   contact
     "WG Web:   <https://datatracker.ietf.org/wg/dots/>
      WG List:  <mailto:dots&ietf.org>

      Editor:  Mohamed Boucadair
               <mailto:mohamed.boucadair&orange.com>

      Editor:  Jon Shallow
               <mailto:supjps-ietf&jpshallow.com>

      Author:  Konda, Tirumaleswar Reddy.K
               <mailto:TirumaleswarReddy_Konda&McAfee.com>

      Author:  Prashanth Patil
               <mailto:praspati&cisco.com>

      Author:  Andrew Mortensen
               <mailto:amortensen&arbor.net>

      Author:  Nik Teague
               <mailto:nteague&ironmountain.co.uk>";
   description
     "This module contains YANG definition for the signaling
      messages exchanged between a DOTS client and a DOTS server.

      Copyright (c) 2020 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 Simplified BSD License



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      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 8782; see
      the RFC itself for full legal notices.";

   revision 2020-07-02 {
     description
       "Updated revision to comply with RFC8791.";
     reference
       "RFC xxxx: A YANG Data Model for Distributed Denial-of-Service
                  Open Threat Signaling (DOTS) Signal Channel";
   }
   revision 2020-05-28 {
     description
       "Initial revision.";
     reference
       "RFC 8782: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Signal Channel Specification";
   }

   /*
    * Groupings
    */

   grouping mitigation-scope {
     description
       "Specifies the scope of the mitigation request.";
     list scope {
       description
         "The scope of the request.";
       uses ietf-data:target;
       leaf-list alias-name {
         type string;
         description
           "An alias name that points to a resource.";
       }
       leaf lifetime {
         type int32;
         units "seconds";
         default "3600";
         description
           "Indicates the lifetime of the mitigation request.

            A lifetime of '0' in a mitigation request is an
            invalid value.




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            A lifetime of negative one (-1) indicates indefinite
            lifetime for the mitigation request.";
       }
       leaf trigger-mitigation {
         type boolean;
         default "true";
         description
           "If set to 'false', DDoS mitigation will not be
            triggered unless the DOTS signal channel
            session is lost.";
       }
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf mid {
             type uint32;
             description
               "Mitigation request identifier.

                This identifier must be unique for each mitigation
                request bound to the DOTS client.";
           }
           leaf mitigation-start {
             type uint64;
             description
               "Mitigation start time is represented in seconds
                relative to 1970-01-01T00:00:00Z in UTC time.";
           }
           leaf status {
             type iana-signal:status;
             description
               "Indicates the status of a mitigation request.
                It must be included in responses only.";
           }
           container conflict-information {
             description
               "Indicates that a conflict is detected.
                Must only be used for responses.";
             leaf conflict-status {
               type iana-signal:conflict-status;
               description
                 "Indicates the conflict status.";
             }



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             leaf conflict-cause {
               type iana-signal:conflict-cause;
               description
                 "Indicates the cause of the conflict.";
             }
             leaf retry-timer {
               type uint32;
               units "seconds";
               description
                 "The DOTS client must not resend the
                  same request that has a conflict before the expiry of
                  this timer.";
             }
             container conflict-scope {
               description
                 "Provides more information about the conflict scope.";
               uses ietf-data:target {
                 when "/dots-signal/scope/conflict-information/"
                    + "conflict-cause = 'overlapping-targets'";
               }
               leaf-list alias-name {
                 when "../../conflict-cause = 'overlapping-targets'";
                 type string;
                 description
                   "Conflicting alias-name.";
               }
               list acl-list {
                 when "../../conflict-cause ="
                    + " 'conflict-with-acceptlist'";
                 key "acl-name";
                 description
                   "List of conflicting ACLs as defined in the DOTS data
                    channel.  These ACLs are uniquely defined by
                    cuid and acl-name.";
                 leaf acl-name {
                   type leafref {
                     path "/ietf-data:dots-data/ietf-data:dots-client/"
                        + "ietf-data:acls/ietf-data:acl/ietf-data:name";
                   }
                   description
                     "Reference to the conflicting ACL name bound to
                      a DOTS client.";
                 }
                 leaf acl-type {
                   type leafref {
                     path "/ietf-data:dots-data/ietf-data:dots-client/"
                        + "ietf-data:acls/ietf-data:acl/ietf-data:type";
                   }



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                   description
                     "Reference to the conflicting ACL type bound to
                      a DOTS client.";
                 }
               }
               leaf mid {
                 when "../../conflict-cause = 'overlapping-targets'";
                 type uint32;
                 description
                   "Reference to the conflicting 'mid' bound to
                    the same DOTS client.";
               }
             }
           }
           leaf bytes-dropped {
             type yang:zero-based-counter64;
             units "bytes";
             description
               "The total dropped byte count for the mitigation
                request since the attack mitigation was triggered.
                The count wraps around when it reaches the maximum value
                of counter64 for dropped bytes.";
           }
           leaf bps-dropped {
             type yang:gauge64;
             description
               "The average number of dropped bits per second for
                the mitigation request since the attack
                mitigation was triggered.  This should be over
                five-minute intervals (that is, measuring bytes
                into five-minute buckets and then averaging these
                buckets over the time since the mitigation was
                triggered).";
           }
           leaf pkts-dropped {
             type yang:zero-based-counter64;
             description
               "The total number of dropped packet count for the
                mitigation request since the attack mitigation was
                triggered.  The count wraps around when it reaches
                the maximum value of counter64 for dropped packets.";
           }
           leaf pps-dropped {
             type yang:gauge64;
             description
               "The average number of dropped packets per second
                for the mitigation request since the attack
                mitigation was triggered.  This should be over



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                five-minute intervals (that is, measuring packets
                into five-minute buckets and then averaging these
                buckets over the time since the mitigation was
                triggered).";
           }
           leaf attack-status {
             type iana-signal:attack-status;
             description
               "Indicates the status of an attack as seen by the
                DOTS client.";
           }
         }
       }
     }
   }

   grouping config-parameters {
     description
       "Subset of DOTS signal channel session configuration.";
     container heartbeat-interval {
       description
         "DOTS agents regularly send heartbeats to each other
          after mutual authentication is successfully
          completed in order to keep the DOTS signal channel
          open.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value {
             type uint16;
             units "seconds";
             description
               "Maximum acceptable heartbeat-interval value.";
           }
           leaf min-value {
             type uint16;
             units "seconds";
             description
               "Minimum acceptable heartbeat-interval value.";
           }
         }
       }
       leaf current-value {



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         type uint16;
         units "seconds";
         default "30";
         description
           "Current heartbeat-interval value.

            '0' means that heartbeat mechanism is deactivated.";
       }
     }
     container missing-hb-allowed {
       description
         "Maximum number of missing heartbeats allowed.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value {
             type uint16;
             description
               "Maximum acceptable missing-hb-allowed value.";
           }
           leaf min-value {
             type uint16;
             description
               "Minimum acceptable missing-hb-allowed value.";
           }
         }
       }
       leaf current-value {
         type uint16;
         default "15";
         description
           "Current missing-hb-allowed value.";
       }
     }
     container probing-rate {
       description
         "The limit for sending Non-confirmable messages with
          no response.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {



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           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value {
             type uint16;
             units "byte/second";
             description
               "Maximum acceptable probing-rate value.";
           }
           leaf min-value {
             type uint16;
             units "byte/second";
             description
               "Minimum acceptable probing-rate value.";
           }
         }
       }
       leaf current-value {
         type uint16;
         units "byte/second";
         default "5";
         description
           "Current probing-rate value.";
       }
     }
     container max-retransmit {
       description
         "Maximum number of retransmissions of a Confirmable
          message.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value {
             type uint16;
             description
               "Maximum acceptable max-retransmit value.";
           }
           leaf min-value {
             type uint16;
             description
               "Minimum acceptable max-retransmit value.";
           }
         }



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       }
       leaf current-value {
         type uint16;
         default "3";
         description
           "Current max-retransmit value.";
       }
     }
     container ack-timeout {
       description
         "Initial retransmission timeout value.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value-decimal {
             type decimal64 {
               fraction-digits 2;
             }
             units "seconds";
             description
               "Maximum ack-timeout value.";
           }
           leaf min-value-decimal {
             type decimal64 {
               fraction-digits 2;
             }
             units "seconds";
             description
               "Minimum ack-timeout value.";
           }
         }
       }
       leaf current-value-decimal {
         type decimal64 {
           fraction-digits 2;
         }
         units "seconds";
         default "2";
         description
           "Current ack-timeout value.";
       }
     }
     container ack-random-factor {



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       description
         "Random factor used to influence the timing of
          retransmissions.";
       choice direction {
         description
           "Indicates the communication direction in which the
            nodes can be included.";
         case server-to-client-only {
           description
             "These nodes appear only in a mitigation message
              sent from the server to the client.";
           leaf max-value-decimal {
             type decimal64 {
               fraction-digits 2;
             }
             description
               "Maximum acceptable ack-random-factor value.";
           }
           leaf min-value-decimal {
             type decimal64 {
               fraction-digits 2;
             }
             description
               "Minimum acceptable ack-random-factor value.";
           }
         }
       }
       leaf current-value-decimal {
         type decimal64 {
           fraction-digits 2;
         }
         default "1.5";
         description
           "Current ack-random-factor value.";
       }
     }
   }

   grouping signal-config {
     description
       "DOTS signal channel session configuration.";
     container mitigating-config {
       description
         "Configuration parameters to use when a mitigation
          is active.";
       uses config-parameters;
     }
     container idle-config {



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       description
         "Configuration parameters to use when no mitigation
          is active.";
       uses config-parameters;
     }
   }

   grouping redirected-signal {
     description
       "Grouping for the redirected signaling.";
     choice direction {
       description
         "Indicates the communication direction in which the
          nodes can be included.";
       case server-to-client-only {
         description
           "These nodes appear only in a mitigation message
            sent from the server to the client.";
         leaf alt-server {
           type string;
           mandatory true;
           description
             "FQDN of an alternate server.";
         }
         leaf-list alt-server-record {
           type inet:ip-address;
           description
             "List of records for the alternate server.";
         }
       }
     }
   }

   /*
    * DOTS Signal Channel Structure
    */

   sx:structure dots-signal {
     description
       "Main structure for DOTS signal message.

        A DOTS signal message can be a mitigation, a configuration,
        or a redirected signal message.";
     choice message-type {
       description
         "Can be a mitigation, a configuration, or a redirect
          message.";
       case mitigation-scope {



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         description
           "Mitigation scope of a mitigation message.";
         uses mitigation-scope;
         reference
           "Section 4.4 of RFC 8782";
       }
       case signal-config {
         description
           "Configuration message.";
         uses signal-config;
         reference
           "Section 4.5 of RFC 8782";
       }
       case redirected-signal {
         description
           "Redirected signaling.";
         uses redirected-signal;
         reference
           "Section 4.6 of RFC 8782";
       }
       case heartbeat {
         description
           "DOTS heartbeats.";
         leaf peer-hb-status {
           type boolean;
           mandatory true;
           description
             "Indicates whether a DOTS agent receives heartbeats
              from its peer.  The value is set to 'true' if the
              DOTS agent is receiving heartbeat messages
              from its peer.";
         }
         reference
           "Section 4.7 of RFC 8782";
       }
     }
   }
 }
 <CODE ENDS>

5.  Security Considerations

   This document defines YANG data structures that are meant to be used
   as an abstract representation of DOTS signal channel messages.  As
   such, this document does not introduce any new vulnerabilities beyond
   those specified Section 10 of [RFC8782].





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6.  IANA Considerations

   This document requests IANA to register the following URI in the "ns"
   subregistry within the "IETF XML Registry" [RFC3688]:

         URI: urn:ietf:params:xml:ns:yang:ietf-dots-signal-channel
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

   This document requests IANA to register the following YANG modules in
   the "YANG Module Names" subregistry [RFC6020] within the "YANG
   Parameters" registry.

         Name: ietf-dots-signal-channel
         Namespace: urn:ietf:params:xml:ns:yang:ietf-dots-signal-channel
         Maintained by IANA: N
         Prefix: signal
         Reference: RFC XXXX

7.  Acknowledgements

   Many thanks to Martin Bjoerklund for the suggestion to use RFC8791.

   The initial version of the DOTS signal channel YANG model was
   specified in [RFC8782] authored by Tirumaleswar Reddy.K, Mohamed
   Boucadair, Prashanth Patil, Andrew Mortensen, and Nik Teague.

8.  References

8.1.  Normative References

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

   [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>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7252]  Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
              Application Protocol (CoAP)", RFC 7252,
              DOI 10.17487/RFC7252, June 2014,
              <https://www.rfc-editor.org/info/rfc7252>.



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   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8782]  Reddy.K, T., Ed., Boucadair, M., Ed., Patil, P.,
              Mortensen, A., and N. Teague, "Distributed Denial-of-
              Service Open Threat Signaling (DOTS) Signal Channel
              Specification", RFC 8782, DOI 10.17487/RFC8782, May 2020,
              <https://www.rfc-editor.org/info/rfc8782>.

   [RFC8783]  Boucadair, M., Ed. and T. Reddy.K, Ed., "Distributed
              Denial-of-Service Open Threat Signaling (DOTS) Data
              Channel Specification", RFC 8783, DOI 10.17487/RFC8783,
              May 2020, <https://www.rfc-editor.org/info/rfc8783>.

   [RFC8791]  Bierman, A., Bjoerklund, M., and K. Watsen, "YANG Data
              Structure Extensions", RFC 8791, DOI 10.17487/RFC8791,
              June 2020, <https://www.rfc-editor.org/info/rfc8791>.

8.2.  Informative References

   [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>.

Authors' Addresses

   Mohamed Boucadair
   Orange
   Rennes  35000
   France

   Email: mohamed.boucadair@orange.com


   Jon Shallow
   United Kingdom

   Email: supjps-ietf@jpshallow.com












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