CCAMP Working Group                                           J. Ahlberg
Internet-Draft                                               Ericsson AB
Intended status: Standards Track                                   M. Ye
Expires: January 4, April 26, 2018                              Huawei Technologies
                                                                   X. Li
                                                 NEC Laboratories Europe
                                                               K. Kawada
                                                         NEC Corporation
                                                           CJ. Bernardos
                                        Universidad Carlos III de Madrid
                                                            D. Spreafico
                                                              Nokia - IT
                                                             M. Vaupotic
                                                          Aviat Networks
                                                            July 3,
                                                        October 23, 2017

               A YANG Data Model for Microwave Radio Link
                      draft-ietf-ccamp-mw-yang-01
                      draft-ietf-ccamp-mw-yang-02

Abstract

   This document defines a YANG data model in order to for control and
   manage management
   of the radio link interfaces, and the their connectivity to packet
   (typically Ethernet) interfaces in a microwave/millimeter wave node.
   The data nodes for management of the interface protection
   functionality is broken out into a separate and generic YANG data
   model in order to make it available also for other interface types.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

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 http://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 4, April 26, 2018.

Copyright Notice

   Copyright (c) 2017 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
   (http://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 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.  Terminology and Definitions . . . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Microwave Radio Link YANG Data Model (Tree Structure)  . . Model. . . . . . . . . . . . .   4
     3.1.  the  YANG Tree . . . . . . . . . . . . . . . . . . . . . . . .   4
     3.2.  Explanation of the Microwave Data Model . . . . . . . . .   5
   4.  Microwave Radio Link YANG Module  . . . . . . . . . . . . . .   6
   5.  Interface Protection YANG Module  . . . . . . . . . . . . . .   6
   5.  30
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  33
   6.  36
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  34
   7.  36
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  34
     7.1.  37
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  34
     7.2.  37
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  34  37
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  35  38

1.  Terminology and Definitions

   The following terms are used in this document:

   Carrier Termination (CT) is an interface for the capacity provided
   over the air by a single carrier.  It is typically defined by its
   transmitting and receiving frequencies.

   Radio Link Terminal (RLT) is an interface providing packet capacity
   and/or TDM capacity to the associated Ethernet and/or TDM interfaces
   in a node and used for setting up a transport service over a
   microwave/millimeter wave link.

   The following acronyms are used in this document:

   ACM Adaptive Coding Modulation

   ATPC Automatic Transmit Power Control

   CM Coding Modulation
   CT Carrier Termination

   RLT Radio Link Terminal

   RTPC Remote Transmit Power Control

   XPIC Cross Polarization Interference Cancellation

   MIMO Multiple-Input Multiple-Output

2.  Introduction

   This document defines a YANG data model for management and control of
   the radio link interface(s) and the relationship to packet (typically
   Ethernet) and/or TDM interfaces in a microwave/millimeter wave node.
   ETSI EN 302 217 series defines the characteristics and requirements
   of microwave/millimeter wave equipment and antennas. Especially ETSI
   EN 302 217-2 [EN 302 217-2] specifies the essential parameters for
   the systems operating from 1.4GHz to 86GHz. The data model includes
   configuration and state data. data according to the new Network Management
   Datastore Architecture [NMDA].

   The design of the data model follows the framework for management and
   control of microwave and millimeter wave interface parameters defined
   in [I-D.ietf-ccamp-microwave-framework].  This framework identifies
   the need and the scope of the YANG data model, the use cases and
   requirements that the model needs to support.  Moreover, it provides
   a detailed gap analysis to identify the missing parameters and
   functionalities of the existing and established models to support the
   specified use cases and requirements, and based on that recommends
   how the gaps should be filled with the development of the new model.

   According to the conclusion of the gap analysis, the structure of the
   data model is based on the structure defined in
   [I-D.ahlberg-ccamp-microwave-radio-link] and it augments RFC 7223 [RFC7223bis]
   to align with the same structure for management of the packet
   interfaces.  More specifically, the model will include interface
   layering to manage the capacity provided by a radio link terminal for
   the associated Ethernet and TDM interfaces, using the principles for
   interface layering described in RFC 7223 bis as a basis.

   The data nodes for management of the interface protection
   functionality is broken out into a separate and generic YANG data
   module in order to make it available also for other interface types.

   The designed YANG data model uses established microwave equipment
   and radio standards, such as ETSI EN 302 217-2, and the IETF: Radio
   Link Model[I-D.ahlberg-ccamp-microwave-radio-link] and the ONF:
   Microwave Modeling[ONF-model] as the basis for the definition of the
   detailed leafs/parameters, and proposes new ones to cover identified
   gaps which are analysed in[I-D.ietf-ccamp-microwave-framework].

3.  Microwave Radio Link YANG Data Model (Tree Structure)

3.1.  the  YANG Tree

   module: ietf-microwave-radio-link
       +--rw radio-link-protection-groups
       |  +--rw radio-link-protection-group* protection-group* [name]
       |     +--rw name                            string
       |     +--rw protection-architecture-type?   identityref
       |     +--rw protection-members*             if:interface-ref
       |     +--rw protection-operation-type?      enumeration
       |     +--rw working-entity*                 if:interface-ref
       |     +--rw revertive-wait-to-restore?      uint16
       |     +--rw radio-link-protection-members*   if:interface-ref hold-off-timer?                 uint16
       |     +--rw protection-status?              identityref
       |     +---x protection-external-commands
       |        +---w input
       |           +---w protection-external-command?   identityref
     +--ro radio-link-protection-groups-state
     |  +--ro radio-link-protection-group* [name]
     |     +--ro name                 string
     |     +--ro protection-status?   identityref
       +--rw xpic-pairs {xpic}?
       |  +--rw xpic-pair* [name]
       |     +--rw name            string
       |     +--rw enabled?        boolean
       |     +--rw xpic-members*   if:interface-ref
       +--rw mimo-groups {mimo}?
          +--rw mimo-group* [name]
             +--rw name            string
             +--rw enabled?        boolean
             +--rw mimo-members*   if:interface-ref
     augment /if:interfaces/if:interface:
       +--rw id?                     string
       +--rw mode                    identityref
       +--rw carrier-terminations*   if:interface-ref
       +--rw rlp-groups*             leafref
       |       -> /radio-link-protection-groups/protection-group/name
       +--rw xpic-pairs*             -> /xpic-pairs/xpic-pair/name
       |       {xpic}?
       +--rw mimo-group? mimo-groups*            -> /mimo-groups/mimo-group/name
       |       {mimo}?
       +--rw tdm-connections* [tdm-type] {tdm}?
          +--rw tdm-type             identityref
          +--rw tdm-connections      uint16
     augment /if:interfaces/if:interface:
       +--rw carrier-id?                     string
       +--rw tx-enabled?                     boolean
       +--ro tx-oper-status?                 enumeration
       +--rw tx-frequency                    uint32
       +--rw rx-frequency?                   uint32
       +--rw duplex-distance?                uint32
       +--rw channel-separation              uint32
       +--rw polarization?                   enumeration
       +--rw power-mode                      enumeration
       +--rw selected-output-power maximum-nominal-power           power
       +--rw atpc-lower-threshold            power
       +--rw atpc-upper-threshold            power
       +--ro actual-transmitted-level?       power
       +--ro actual-received-level?          power
       +--rw coding-modulation-mode          enumeration
       +--rw selected-cm                     identityref
       +--rw selected-min-acm                identityref
       +--rw selected-max-acm                identityref
     +--rw if-loop?                     enumeration
     +--rw rf-loop?                     enumeration
       +--ro actual-tx-cm?                   identityref
       +--ro actual-snir?                    decimal64
       +--ro actual-xpi?                     decimal64 {xpic}?
       +--rw ct-performance-thresholds
       |  +--rw received-level-alarm-threshold?      power
       |  +--rw transmitted-level-alarm-threshold?   power
       |  +--rw ber-alarm-threshold?                 enumeration
   augment /if:interfaces-state/if:interface:
     +--ro tx-oper-status?
       +--rw if-loop?                        enumeration
       +--rw rf-loop?                        enumeration
     +--ro actual-transmitted-level?   power
     +--ro actual-received-level?      power
     +--ro actual-tx-cm?               identityref
     +--ro actual-snir?                decimal64
     +--ro actual-xpi?                 decimal64 {xpic}?
       +--ro capabilities
       |  +--ro min-tx-frequency?          uint32
       |  +--ro max-tx-frequency?          uint32
       |  +--ro min-rx-frequency?          uint32
       |  +--ro max-rx-frequency?          uint32
       |  +--ro available-min-output-power? minimum-power?             power
       |  +--ro available-max-output-power? maximum-available-power?   power
       |  +--ro available-min-acm?         identityref
       |  +--ro available-max-acm?         identityref
   augment /if:interfaces-state/if:interface/if:statistics:
       +--ro error-performance-statistics
       |  +--ro bbe?   yang:counter32
       |  +--ro es?    yang:counter32
       |  +--ro ses?   yang:counter32
       |  +--ro uas?   yang:counter32
       +--ro radio-performance-statistics
          +--ro min-rltm?   power
          +--ro max-rltm?   power
          +--ro min-tltm?   power
          +--ro max-tltm?   power

3.2.  Explanation of the Microwave Data Model

   The leaves leafs in the Interface Management Module augmented by Radio Link
   Terminal (RLT) and Carrier Termination (CT) are not always relevant.
   applicable.

   "/interfaces/interface/enabled" is not relevant applicable for RLT. Enable and
   disable of an interface is done in the constituent CTs.

   The packet related measurements "in-octets", "in-unicast-pkts", "in-
   broadcast-pkts", "in-multicast-pkts", "in-discards", "in-errors",
   "in-unknown-protos", "out-octets", "out-unicast-pkts", "out-
   broadcast-pkts", "out-multicast-pkts", "out-discards", "out-errors"
   are not within the scope of the microwave radio link domain and
   therefore not relevant applicable for RLT and CT.

4.  Microwave Radio Link YANG Module

   <CODE BEGINS> file "ietf-microwave-radio-link.yang"

   module ietf-microwave-radio-link {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-microwave-radio-link";
     prefix "mrl"; mrl;

     import ietf-yang-types {
       prefix yang;
     }

     import ietf-interfaces {
       prefix if;
     }

     import ietf-interface-protection {
       prefix ifprot;
     }

     import iana-if-type {
       prefix ianaift;
     }

    organization
      "Internet Engineering Task Force (IETF) CCAMP WG";
    contact
     "
     WG
      "WG List: <mailto:ccamp@ietf.org>

      ID-draft authors:
        Jonas Ahlberg (jonas.ahlberg@ericsson.com);
        Min Ye (amy.yemin@huawei.com);
        Xi Li (Xi.Li@neclab.eu);
        Koji Kawada (k-kawada@ah.jp.nec.com)
        Carlos J. Bernardos (cjbc@it.uc3m.es)
        Daniela Spreafico (daniela.spreafico@nokia.com)
        Marko Vaupotic (Marko.Vaupotic@aviatnet.com)
     "; (Marko.Vaupotic@aviatnet.com)";

     description
       "This is a module for the entities in
       a generic microwave system.";

     revision 2017-10-23 {
       description
       "Break out protection functionality to a generic module
        and update to follow the new NMDA style.";
       reference "";
     }
     revision 2017-06-21 {
       description
       "Updated draft revision with updates of some descriptions to
        increase clarity and some minor adjustments of the model.";
       reference "";
     }
     revision 2016-12-22 {
       description
       "Draft revision covering a complete scope for configuration
        and state data for radio link interfaces.";
       reference "";
     }
     revision 2016-10-29 {
       description
       "Draft revision.";
       reference "";
     }

     /*
      * Features
      */

     feature xpic {
       description
         "Indicates that the device supports XPIC.";
       reference "ETSI TR 102 311";
     }

     feature mimo {
       description
         "Indicates that the device supports MIMO.";
       reference "ETSI TR 102 311";
     }

     feature tdm {
       description
         "Indicates that the device supports TDM.";
     }

     /*
      * Interface identities
      */

     identity radio-link-terminal {
       base ianaift:iana-interface-type;
       description
         "Interface identity for a radio link terminal.";
     }
     identity carrier-termination {
       base ianaift:iana-interface-type;
       description
        "Interface identity for a carrier termination.";
     }

     /*
      * Radio-link-terminal mode identities
      */

     identity rlt-mode {
       description
         "A description of the mode in which the radio link
         terminal is configured. The format is X plus Y.
         X represent the number of bonded carrier terminations.
         Y represent the number of protecting carrier
         terminations.";
     }

     identity one-plus-zero {
       base rlt-mode;
       description
         "1 carrier termination only.";
     }

     identity one-plus-one {
       base rlt-mode;
       description
         "1 carrier termination
         and 1 protecting carrier termination.";
     }

     identity two-plus-zero {
       base rlt-mode;
       description
         "2 bonded carrier terminations.";
     }

     /*
      * Coding and modulation identities
      */

     identity coding-modulation {
       description
         "The coding and modulation schemes.";
     }

     identity half-bpsk-strong {
       base coding-modulation;
       description
         "Half BPSK strong coding and modulation scheme.";
     }
     identity half-bpsk {
       base coding-modulation;
       description
         "Half BPSK coding and modulation scheme.";
     }

     identity half-bpsk-light {
       base coding-modulation;
       description
         "Half BPSK light coding and modulation scheme.";
     }

     identity bpsk-strong {
       base coding-modulation;
       description
         "BPSK strong coding and modulation scheme.";
     }

     identity bpsk {
       base coding-modulation;
       description
         "BPSK coding and modulation scheme.";
     }

     identity bpsk-light {
       base coding-modulation;
       description
         "BPSK light coding and modulation scheme.";
     }

     identity qpsk {
       base coding-modulation;
       description
         "QPSK coding and modulation scheme.";
     }

     identity qam-4-strong {
       base coding-modulation;
       description
         "4 QAM strong coding and modulation scheme.";
     }

     identity qam-4 {
       base coding-modulation;
       description
         "4 QAM coding and modulation scheme.";
     }
     identity qam-4-light {
       base coding-modulation;
       description
         "4 QAM light coding and modulation scheme.";
     }

     identity qam-16-strong {
       base coding-modulation;
       description
         "16 QAM strong coding and modulation scheme.";
     }

     identity qam-16 {
       base coding-modulation;
       description
         "16 QAM coding and modulation scheme.";
     }

     identity qam-16-light {
       base coding-modulation;
       description
         "16 QAM light coding and modulation scheme.";
     }

     identity qam-32-strong {
       base coding-modulation;
       description
         "32 QAM strong coding and modulation scheme.";
     }

     identity qam-32 {
       base coding-modulation;
       description
         "32 QAM coding and modulation scheme.";
     }

     identity qam-32-light {
       base coding-modulation;
       description
         "32 QAM light coding and modulation scheme.";
     }

     identity qam-64-strong {
       base coding-modulation;
       description
         "64 QAM strong coding and modulation scheme.";
     }
     identity qam-64 {
       base coding-modulation;
       description
         "64 QAM coding and modulation scheme.";
     }

     identity qam-64-light {
       base coding-modulation;
       description
         "64 QAM light coding and modulation scheme.";
     }

     identity qam-128-strong {
       base coding-modulation;
       description
         "128 QAM strong coding and modulation scheme.";
     }

     identity qam-128 {
       base coding-modulation;
       description
         "128 QAM coding and modulation scheme.";
     }

     identity qam-128-light {
       base coding-modulation;
       description
         "128 QAM light coding and modulation scheme.";
     }

     identity qam-256-strong {
       base coding-modulation;
       description
         "256 QAM strong coding and modulation scheme.";
     }

     identity qam-256 {
       base coding-modulation;
       description
         "256 QAM coding and modulation scheme.";
     }

     identity qam-256-light {
       base coding-modulation;
       description
         "256 QAM light coding and modulation scheme.";
     }
     identity qam-512-strong {
       base coding-modulation;
       description
         "512 QAM strong coding and modulation scheme.";
     }

     identity qam-512 {
       base coding-modulation;
       description
         "512 QAM coding and modulation scheme.";
     }

     identity qam-512-light {
       base coding-modulation;
       description
         "512 QAM light coding and modulation scheme.";
     }

     identity qam-1024-strong {
       base coding-modulation;
       description
         "1024 QAM strong coding and modulation scheme.";
     }

     identity qam-1024 {
       base coding-modulation;
       description
         "1024 QAM coding and modulation scheme.";
     }

     identity qam-1024-light {
       base coding-modulation;
       description
         "1024 QAM light coding and modulation scheme.";
     }

     identity qam-2048-strong {
       base coding-modulation;
       description
         "2048 QAM strong coding and modulation scheme.";
     }

     identity qam-2048 {
       base coding-modulation;
       description
         "2048 QAM coding and modulation scheme.";
     }
     identity qam-2048-light {
       base coding-modulation;
       description
         "2048 QAM light coding and modulation scheme.";
     }

     identity qam-4096-strong {
       base coding-modulation;
       description
         "4096 QAM strong coding and modulation scheme.";
     }

     identity qam-4096 {
       base coding-modulation;
       description
         "4096 QAM coding and modulation scheme.";
     }

     identity qam-4096-light {
       base coding-modulation;
       description
         "4096 QAM light coding and modulation scheme.";
     }

     /*
      * Protection architecture type TDM-type identities
      */

     identity protection-architecture-type tdm-type {
       description
         "protection architecture type";
         "A description of the type of TDM connection,
         also indicating the supported capacity of the
         connection.";
     }

     identity one-plus-one-type E1 {
       base protection-architecture-type;
       description
         "One carrier termination and
         one protecting carrier termination.";
     }

     identity one-to-n-type {
       base protection-architecture-type;
       description
         "One carrier termination protecting
         n other carrier terminations.";
     }

     /*
      * Protection states identities
      */

     identity protection-states {
       description
        "Identities describing the status of the protection,
        in a group of carrier terminations configured in
        a radio link protection mode.";
     }

     identity unprotected {
       base protection-states;
       description "Not protected";
     }

     identity protected {
       base protection-states;
       description "Protected";
     }

     identity unable-to-protect {
       base protection-states;
       description "Unable to protect";
     }

     /*
      * protection-external-commands identities
      */

     identity protection-external-commands{
       description
         "Protection external commands for trouble shooting purpose.";
     }

     identity manual-switch{
       base protection-external-commands;
       description
         "A switch action initiated by an operator command. It switches
         normal traffic signal to the protection transport entity.";
     }

     identity forced-switch{
       base protection-external-commands;
       description
         "A switch action initiated by an operator command. It switches
          normal traffic signal to the protection transport entity and
              forces it to remain on that entity even when criteria for
              switching back to the orignal entity are fulfilled.";
     }

     /*
      * TDM-type identities
      */

     identity tdm-type {
       description
         "A description of the type of TDM connection,
         also indicating the supported capacity of the
         connection.";
     }

     identity E1 {
       base tdm-type; tdm-type;
       description
         "E1 connection, 2,048 Mbit/s.";
     }

     identity STM-1 {
       base tdm-type;
       description
         "STM-1 connection, 155,52 Mbit/s.";
     }
     /*
      * Typedefs
      */

     typedef power {
       type decimal64 {
         fraction-digits 1;
       }
       description
         "Type used for power values, selected and measured.";
     }

     /*
      * Radio Link Terminal (RLT) - Configuration data nodes
      */

     augment "/if:interfaces/if:interface" {
       when "if:type = 'mrl:radio-link-terminal'";
       description
         "Addition of data nodes for radio link terminal to
          the standard Interface data model, for interfaces of
          the type 'radio-link-terminal'.";

       leaf id {
         type string;
         default "";
         description
           "ID of the radio link terminal. Used by far-end when
            checking that it's connected to the correct RLT.";
       }

       leaf mode {
         type identityref {
           base rlt-mode;
         }
         mandatory true;
         description
           "A description of the mode in which the radio link
            terminal is configured. The format is X plus Y.
            X represent the number of bonded carrier terminations.
            Y represent the number of protecting carrier
            terminations.";
       }
       leaf-list carrier-terminations {
         type if:interface-ref;
         must "/if:interfaces/if:interface[if:name = current()]"
            + "/if:type = 'mrl:carrier-termination'" {
           description
             "The type of interface must be
              'carrier-termination'.";
         }
         min-elements 1;
         description
           "A list of references to carrier terminations
            included in the radio link terminal.";
       }

       leaf-list rlp-groups {
         type leafref {
           path "/mrl:radio-link-protection-groups/"
              + "mrl:radio-link-protection-group/mrl:name"; "mrl:protection-group/mrl:name";
         }
         description
           "A list of references to the carrier termination
            groups configured for radio link protection in this
            radio link terminal.";
       }

       leaf-list xpic-pairs {
         if-feature xpic;
         type leafref {
           path "/mrl:xpic-pairs/mrl:xpic-pair/mrl:name";
         }
         description
           "A list of references to the XPIC pairs used in this
            radio link terminal. One pair can be used by two
            terminals.";
         reference "ETSI TR 102 311";
       }

       leaf mimo-group

       leaf-list mimo-groups {
         if-feature mimo;
         type leafref {
           path "/mrl:mimo-groups/mrl:mimo-group/mrl:name";
         }
         description
           "A reference to the MIMO group used in this
            radio link terminal. One group can be used by more
            than one terminal.";
         reference "ETSI TR 102 311";
       }
       list tdm-connections {
         if-feature tdm;
         key "tdm-type";
         description
          "A list stating the number of active TDM connections
           of a specified tdm-type that is configured to be
           supported by the RLT.";
         leaf tdm-type {
           type identityref {
             base tdm-type;
           }
           description
             "The type of TDM connection, which also indicates
             the supported capacity.";
         }
         leaf tdm-connections {
           type uint16;
           mandatory true;
           description
             "Number of connections of the specified type.";
         }
       }
     }

     /*
      * Carrier Termination - Configuration data nodes
      */

     augment "/if:interfaces/if:interface" {
       when "if:type = 'mrl:carrier-termination'";
       description
         "Addition of data nodes for carrier termination to
          the standard Interface data model, for interfaces
          of the type 'carrier-termination'.";

       leaf carrier-id {
         type string;
         default "A";
         description
           "ID of the carrier. (e.g. A, B, C or D)
            Used in XPIC & MIMO configurations to check that
            the carrier termination is connected to the correct
            far-end carrier termination. Should be the same
            carrier ID on both sides of the hop.
            Defaulted when not MIMO or XPIC.";
       }
       leaf tx-enabled {
         type boolean;
         default "false";
         description
           "Disables (false) or enables (true) the transmitter.
            Only applicable when the interface is enabled
            (interface:enabled = true) otherwise it's always
            disabled.";
       }

       leaf tx-oper-status {
         type enumeration {
           enum "off" {
             description "Transmitter is off.";
           }
           enum "on" {
             description "Transmitter is on.";
           }
           enum "standby" {
             description "Transmitter is in standby.";
           }
         }
         config false;
         description
           "Shows the operative status of the transmitter.";
       }

       leaf tx-frequency {
         type uint32;
         units "kHz";
         mandatory true;
         description
           "Selected transmitter frequency.";
       }

       leaf rx-frequency {
         type uint32;
         units "kHz";
         description
           "Selected receiver frequency.
            Overrides existing value in duplex-distance.
            Calculated from tx-frequency and duplex-distance if
            only duplex-distance is configured.
            Must match duplex-distance if both leaves are
            configured in a single operation.";
       }
       leaf duplex-distance {
         type uint32;
         units "kHz";
         description
           "Distance between Tx & Rx frequencies.
            Used to calculate rx-frequency when
            rx-frequency is not specifically configured.
            Overrides existing value in rx-frequency.
            Calculated from tx-frequency and rx-frequency if only
            rx-frequency is configured.
            Must match rx-frequency if both leaves are configured
            in a single operation.";
       }

       leaf channel-separation {
         type uint32;
         units "kHz";
         mandatory true;
         description
           "The amount of bandwidth allocated to a carrier."; carrier. The distance
            between adjacent channels in a radio frequency channels
            arrangement";
         reference "ETSI EN 302 217-1";
       }

       leaf polarization {
         type enumeration {
           enum "horizontal" {
             description "Horizontal polarization.";
           }
           enum "vertical" {
             description "Vertical polarization.";
           }
           enum "not-specified" {
             description "Polarization not specified.";
           }
         }
         default "not-specified";
         description
           "Polarization - A textual description for info only.";
       }

       leaf power-mode {
         type enumeration {
           enum rtpc {
             description
               "Remote Transmit Power Control (RTPC).";

           }
           enum
             reference "ETSI EN 302 217-1";
           }
           enum atpc {
             description
               "Automatic Transmit Power Control (ATPC).";
             reference "ETSI EN 302 217-1";
           }
         }
         mandatory true;
         description
           "A choice of Remote Transmit Power Control (RTPC)
            or Automatic Transmit Power Control (ATPC).";
       }

       leaf selected-output-power maximum-nominal-power {
         type power {
           range "-99..40";
         }
         units "dBm";
         mandatory true;
         description
           "Selected output power in RTPC mode and selected
            maximum output power in ATPC mode. Minimum ouput
            power in ATPC mode is the same as the system
            capability, available-min-output-power.";
         reference "ETSI EN 302 217-1";
       }

       leaf atpc-lower-threshold  {
         when "../power-mode = 'atpc'";
         type power {
           range "-99..-30";
         }
         units "dBm";
         mandatory true;
         description
           "The lower threshold for the input power at far-end
            used in the ATPC mode.";
         reference "ETSI EN 302 217-1";
       }

       leaf atpc-upper-threshold  {
         when "../power-mode = 'atpc'";
         type power {
           range "-99..-30";
         }
         units "dBm";
         mandatory true;
         description
           "The upper threshold for the input power at far-end
            used in the ATPC mode.";
         reference "ETSI EN 302 217-1";
       }
       leaf actual-transmitted-level {
         type power {
           range "-99..40";
         }
         units "dBm";
         config false;
         description
           "Actual transmitted power level (0.1 dBm resolution).";
         reference "ETSI EN 301 129";
       }

       leaf actual-received-level {
         type power {
           range "-99..-20";
         }
         units "dBm";
         config false;
         description
           "Actual received power level (0.1 dBm resolution).";
         reference "ETSI EN 301 129";
       }

       leaf coding-modulation-mode {
         type enumeration {
           enum fixed single {
             description "Fixed coding/modulation."; "a single modulation order only.";
             reference "ETSI EN 302 217-1";
           }
           enum adaptive {
             description "Adaptive coding/modulation.";
             reference "ETSI EN 302 217-1";
           }
         }
         mandatory true;
         description
           "A selection of fixed single or
            adaptive coding/modulation mode.";
       }

       leaf selected-cm {
         when "../coding-modulation-mode = 'fixed'"; 'single'";
         type identityref {
           base coding-modulation;
         }
         mandatory true;
         description
           "Selected fixed the single coding/modulation.";
       }
       leaf selected-min-acm {
         when "../coding-modulation-mode = 'adaptive'";
         type identityref {
           base coding-modulation;
         }
         mandatory true;
         description
           "Selected minimum coding/modulation.
            Adaptive coding/modulation shall not go
            below this value.";
       }

       leaf selected-max-acm {
         when "../coding-modulation-mode = 'adaptive'";
         type identityref {
           base coding-modulation;
         }
         mandatory true;
         description
           "Selected maximum coding/modulation.
            Adaptive coding/modulation shall not go
            above this value.";
       }

       leaf if-loop actual-tx-cm {
         type enumeration {
           enum disabled {
             description "Disables the IF Loop.";
           }
           enum client {
             description "Loops the signal back to the client side.";
           }
           enum radio identityref {
             description "Loops the signal back to the radio side.";
           }
            base coding-modulation;
         }
         default "disabled";
         config false;
         description
           "Enable (client/radio) or disable (disabled) the IF loop,
           which loops the signal back to the client side or
           the radio side.";
           "Actual coding/modulation in transmitting direction.";
       }

       leaf rf-loop actual-snir {
         type enumeration {
           enum disabled decimal64 {
             description "Disables the RF Loop.";
           fraction-digits 1;
           range "0..99";
         }
           enum client {
         units "dB";
         config false;
         description "Loops the
           "Actual signal back to the client side."; noise plus interference ratio.
            (0.1 dB resolution).";
       }
           enum radio

       leaf actual-xpi {
             description "Loops the signal back to the radio side.";
           }
         if-feature xpic;
         type decimal64 {
           fraction-digits 1;
           range "0..99";
         }
         default "disabled";
         units "dB";
         config false;
         description
           "Enable (client/radio) or disable (disabled) the RF loop,
           which loops the signal back
           "The actual carrier to the client side or
           the radio side."; cross-polar interference.
            Only valid if XPIC is enabled. (0.1 dB resolution).";
         reference "ETSI TR 102 311";
       }

       container ct-performance-thresholds {
         description
           "Specification of thresholds for when alarms should
            be sent and cleared for various performance counters.";

         leaf received-level-alarm-threshold {
           type power {
             range "-99..-30";
           }
           units "dBm";
           default "-99";
           description
             "An alarm is sent when the received power level is
              below the specified threshold.";
           reference "ETSI EN 301 129";
         }

         leaf transmitted-level-alarm-threshold {
           type power {
             range "-99..40";
           }
           units "dBm";
           default "-99";
           description
             "An alarm is sent when the transmitted power level
              is below the specified threshold.";
           reference "ETSI EN 301 129";
         }

         leaf ber-alarm-threshold {
           type enumeration {
             enum "10e-9" {
               description "Threshold at 10e-9.";
             }
             enum "10e-8" {
               description "Threshold at 10e-8.";
             }
             enum "10e-7" {
               description "Threshold at 10e-7.";
             }
             enum "10e-6" {
               description "Threshold at 10e-6.";
             }
             enum "10e-5" {
               description "Threshold at 10e-5.";
             }
             enum "10e-4" {
               description "Threshold at 10e-4.";
             }
             enum "10e-3" {
               description "Threshold at 10e-3.";
             }
             enum "10e-2" {
               description "Threshold at 10e-2.";
             }
             enum "10e-1" {
               description "Threshold at 10e-1.";
             }
           }
           default "10e-6";
           description
             "Specification of at which BER an alarm should
              be raised.";
           reference "ETSI EN 302 217-1";
         }
       }

       leaf if-loop {
         type enumeration {
           enum disabled {
             description "Disables the IF Loop.";
           }

     /*
      * Radio Link Terminal - Operational state data nodes
      * Currently nothing in addition
           enum client {
             description
               "Loops the signal back to the general
      * interface-state model.
      */

     /*
      * Carrier Termination - Operational state data nodes
      */

     augment "/if:interfaces-state/if:interface" client side.";
           }
           enum radio {
       when "if:type = 'mrl:carrier-termination'";
             description
         "Addition of state data nodes for carrier termination
               "Loops the signal back to the standard Interface state data model, for interfaces of radio side.";
           }
         }
         default "disabled";
         description
           "Enable (client/radio) or disable (disabled)
            the type 'carrier-termination'."; IF loop, which loops the signal back to
            the client side or the radio side.";
       }

       leaf tx-oper-status rf-loop {
         type enumeration {
           enum "off" disabled {
             description "Transmitter is off."; "Disables the RF Loop.";
           }
           enum "on" client {
             description "Transmitter is on.";
               "Loops the signal back to the client side.";
           }
           enum "standby" radio {
             description "Transmitter is in standby.";
               "Loops the signal back to the radio side.";
           }
         }
         default "disabled";
         description
           "Shows
           "Enable (client/radio) or disable (disabled)
            the operative status of RF loop, which loops the transmitter."; signal back to
            the client side or the radio side.";
       }

       leaf actual-transmitted-level {
         type power

       container capabilities {
           range "-99..40";
         }
         units "dBm";
         config false;
         description
           "Actual transmitted power level (0.1 dBm resolution).";
       }
           "Capabilities of the the installed equipment and
            some selected configurations.";

         leaf actual-received-level min-tx-frequency {
           type power {
           range "-99..-20";
         } uint32;
           units "dBm"; "kHz";
           description
           "Actual received power level (0.1 dBm resolution).";
             "Minimum Tx frequency possible to use.";
         }

         leaf actual-tx-cm max-tx-frequency {
           type identityref {
            base coding-modulation;
         } uint32;
           units "kHz";
           description
           "Actual coding/modulation in transmitting direction.";
             "Maximum Tx frequency possible to use.";
         }

         leaf actual-snir {
         type decimal64 {
           fraction-digits 1;
           range "0..99";
         }
         units "dB";
         description
           "Actual signal to noise plus interference ratio.
            (0.1 dB resolution).";
       }

       leaf actual-xpi {
         if-feature xpic;
         type decimal64 {
           fraction-digits 1;
           range "0..99";
         }
         units "dB";
         description
           "The actual carrier to cross-polar interference.
            Only valid if XPIC is enabled. (0.1 dB resolution).";
       }

       container capabilities {
         description
           "Capabilities of the the installed equipment and
            some selected configurations.";

         leaf min-tx-frequency {
           type uint32;
           units "kHz";
           description
             "Minimum Tx frequency possible to use.";
         }

         leaf max-tx-frequency {
           type uint32;
           units "kHz";
           description
             "Maximum Tx frequency possible to use.";
         }

         leaf min-rx-frequency min-rx-frequency {
           type uint32;
           units "kHz";
           description
             "Minimum Rx frequency possible to use.";
         }

         leaf max-rx-frequency {
           type uint32;
           units "kHz";
           description
             "Maximum Tx frequency possible to use.";
         }
         leaf available-min-output-power minimum-power {
           type power;
           units "dBm";
           description
             "The minimum output power supported.";
           reference "ETSI EN 302 217-1";
         }

         leaf available-max-output-power maximum-available-power {
           type power;
           units "dBm";
           description
             "The maximum output power supported.";
           reference "ETSI EN 302 217-1";
         }

         leaf available-min-acm {
           type identityref {
             base coding-modulation;
           }
           description
             "Minimum coding-modulation possible to use.";
         }

         leaf available-max-acm {
           type identityref {
             base coding-modulation;
           }
           description
             "Maximum coding-modulation possible to use.";
         }
       }
     }

     augment "/if:interfaces-state/if:interface/if:statistics"

       container error-performance-statistics {
       when "../if:type = 'mrl:carrier-termination'";
         config false;
         description
         "Addition of state data nodes in the container
           "ITU-T G.826 error performance statistics relevant for carrier terminations to the standard Interface data
          model, for interfaces of the type 'carrier-termination'.";
            a microwave/millimeter wave carrier.";

         leaf bbe {
           type yang:counter32;
           units "number of block errors";
           description
             "Number of Background Block Errors (BBE) during the
             interval. A BBE is an errored block not occurring as
             part of an SES.";
           reference "ITU-T G.826";
         }
         leaf es {
           type yang:counter32;
           units "seconds";
           description
             "Number of Errored Seconds (ES) since last reset.
              An ES is a one-second period with one or more errored
              blocks or at least one defect.";
           reference "ITU-T G.826";
         }

         leaf ses {
           type yang:counter32;
           units "seconds";
           description
             "Number of Severely Errored Seconds (SES) during the
              interval. SES is a one-second period which contains
              equal or more than 30% errored blocks or at least
              one defect. SES is a subset of ES.";
           reference "ITU-T G.826";
         }

         leaf uas {
           type yang:counter32;
           units "seconds";
           description
             "Number of Unavailable Seconds (UAS), that is, the
              total time that the node has been unavailable during
              a fixed measurement interval.";
           reference "ITU-T G.826";
         }
       }

       container radio-performance-statistics {
         config false;
         description
           "ETSI EN 301 129 radio physical interface statistics relevant
            for a carrier termination.";

         leaf min-rltm {
           type power {
             range "-99..-20";
           }
           units "dBm";
           description
             "Minimum received power level since last reset.";
           reference "ETSI EN 301 129";
         }
         leaf max-rltm {
           type power {
             range "-99..-20";
           }
           units "dBm";
           description
             "Maximum received power level since last reset.";
           reference "ETSI EN 301 129";
         }

         leaf min-tltm {
           type power {
             range "-99..40";
           }
           units "dBm";
           description
             "Minimum transmitted power level since last reset.";
           reference "ETSI EN 301 129";
         }

         leaf max-tltm {
           type power {
             range "-99..40";
           }
         units "dBm";
           units "dBm";
           description
             "Maximum transmitted power level since last reset.";
           reference "ETSI EN 301 129";
         }
       }
     }

     /*
      * Radio Link Protection Groups
      */

     container radio-link-protection-groups {
       description
         "Configuration of radio link protected groups (1+1) of
         carrier terminations in a radio link. More than one
         protected group per radio-link-terminal is allowed.";

       uses ifprot:protection-groups {

         refine protection-group/protection-members {
           must "/if:interfaces/if:interface[if:name = current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a protection member must be
                'carrier-termination'.";
           }
         }
         refine protection-group/working-entity {
           must "/if:interfaces/if:interface[if:name =  current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a working-entity must be
                'carrier-termination'.";
           }
         }
       }
     }

     /*
      * XPIC & MIMO groups - Configuration data nodes
      */

     container xpic-pairs {
       if-feature xpic;
       description
         "Configuration of carrier termination pairs
          for operation in XPIC mode.";
       reference "ETSI TR 102 311";

       list xpic-pair {
         key "name";
         description
           "List of carrier termination pairs in XPIC mode.";

         leaf name {
           type string;
           description
             "Name used for identification of the XPIC pair.";
         }

         leaf enabled {
           type boolean;
           default "false";
           description
             "Enable(true)/disable(false) XPIC";
         }

         leaf-list xpic-members {
           type if:interface-ref;
           must "/if:interfaces/if:interface[if:name = current()]"
             + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a xpic-member must be
               'carrier-termination'.";
           }
           min-elements 2;
           max-elements 2;
           description
             "Association to XPIC pairs used in the radio link
              terminal.";
         }
       }
     }

     container mimo-groups {
       if-feature mimo;
       description
         "Configuration of carrier terminations
         for operation in MIMO mode.";
       reference "ETSI TR 102 311";

       list mimo-group {
         key "name";
         description
           "List of carrier terminations in MIMO mode.";

         leaf name {
           type string;
           description
             "Name used for identification of the MIMO group.";
         }

         leaf enabled {
           type boolean;
           default "false";
           description
             "Enable(true)/disable(false) MIMO";
         }

         leaf-list mimo-members {
           type if:interface-ref;
           must "/if:interfaces/if:interface[if:name = current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a mimo-member must be
                'carrier-termination'.";
           }
           min-elements 2;
           description
             "Association to a MIMO group if used in the radio
              link terminal.";
         }
       }
     }
   }

   <CODE ENDS>

5.  Interface Protection YANG Module

   The data nodes for management of the interface protection
   functionality is broken out from the Microwave Radio Link Module
   into a separate and generic YANG data module in order to make it
   available also for other interface types.

   <CODE BEGINS> file "ietf-interface-protection.yang"

   module ietf-interface-protection {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-interface-protection";
     prefix ifprot;

     import ietf-interfaces {
       prefix if;
     }

     organization
       "Internet Engineering Task Force (IETF) CCAMP WG";
     contact
       "WG List: <mailto:ccamp@ietf.org>

       ID-draft authors:
         Jonas Ahlberg (jonas.ahlberg@ericsson.com);
         Min Ye (amy.yemin@huawei.com);
         Xi Li (Xi.Li@neclab.eu);
         Koji Kawada (k-kawada@ah.jp.nec.com)
         Carlos J. Bernardos (cjbc@it.uc3m.es)
         Daniela Spreafico (daniela.spreafico@nokia.com)
         Marko Vaupotic (Marko.Vaupotic@aviatnet.com)";

     description
       "This is a module for the entities in
       a generic interface protection mechanism.";

     revision 2017-10-19 {
       description
       "Draft revision.";
       reference "";
     }

     /*
      * Protection architecture type identities
      */

     identity protection-architecture-type {
       description
         "protection architecture type";
       reference "ITU-T Rec. G.808.1";
     }
     identity one-plus-one-type {
       base protection-architecture-type;
       description
         "1+1, One interface protects
         another one interface.";
       reference "ITU-T Rec. G.808.1";
     }

     identity one-to-n-type {
       base protection-architecture-type;
       description
         "1:N, One interface protects
         n other interfaces.";
       reference "ITU-T Rec. G.808.1";
     }

     /*
      * Protection states identities
      */

     identity protection-states {
       description
        "Identities describing the status of the protection,
        in a group of interfaces configured in
        a protection mode.";
     }

     identity unprotected {
       base protection-states;
       description "Not protected";
     }

     identity protected {
       base protection-states;
       description "Protected";
     }

     identity unable-to-protect {
       base protection-states;
       description "Unable to protect";
     }

     /*
      * protection-external-commands identities
      */

     identity protection-external-commands{
       description
         "Protection external commands for trouble shooting
          purpose.";
       reference "ITU-T Rec. G.808.1";
     }
     identity manual-switch-working{
       base protection-external-commands;
       description
         "A switch action initiated by an operator command.
          It switches normal traffic signal to the working
          transport entity.";
       reference "ITU-T Rec. G.808.1";
     }

     identity manual-switch-protection{
       base protection-external-commands;
       description
         "A switch action initiated by an operator command.
          It switches normal traffic signal to the protection
          transport entity.";
       reference "ITU-T Rec. G.808.1";
     }

     identity forced-switch{
       base protection-external-commands;
       description
         "A switch action initiated by an operator command.
          It switches normal traffic signal to the protection
          transport entity and forces it to remain on that
          entity even when criteria for switching back to
          the orignal entity are fulfilled.";
       reference "ITU-T Rec. G.808.1";
     }

     identity lockout-of-protection{
       base protection-external-commands;
       description
         "A switch action temporarily disables access to the
          protection transport entity for all signals.";
       reference "ITU-T Rec. G.808.1";
     }

     identity freeze{
       base protection-external-commands;
       description
         "A switch action temporarily prevents any switch action
          to be taken and, as such, freezes the current state.
          Until the freeze is cleared, additional near-end external
          commands are rejected and fault condition changes and
          received APS messages are ignored..";
       reference "ITU-T Rec. G.808.1";
     }
     identity exercise{
       base protection-external-commands;
       description
           "Maximum transmitted power level since last reset.";
         "A switch action to test if the APS communication is
          operating correctly. It is lower priority than any 'real'
          switch request..";
       reference "ITU-T Rec. G.808.1";
     }

     identity clear{
       base protection-external-commands;
       description
         "A action clears all switch commands.";
       reference "ITU-T Rec. G.808.1";
     }

     /*
      * Radio Link Protection Groups - Configuration data nodes
      */

     container radio-link-protection-groups

     grouping protection-groups {
       description
         "Configuration of radio link protected groups (1+1) of
         carrier terminations in a radio link. interfaces
         providing protection for each other. More than one protected
         group per radio-link-terminal higher-layer-interface is allowed.";

       list radio-link-protection-group protection-group {
         key "name";
         description
         "List of protected groups of carrier terminations interfaces
         in a radio link."; higher-layer-interface.";

         leaf name {
           type string;
           description
             "Name used for identification of the radio
              link protection group";
         }

         leaf protection-architecture-type {
           type identityref{
             base protection-architecture-type;
           }
           default "one-plus-one-type";
           description
             "The type of protection architecture used, e.g. one carrier termination
             interface protecting one or several other carrier terminations."; interfaces.";
           reference "ITU-T Rec. G.808.1";
         }
         leaf-list protection-members {
           type if:interface-ref;
           min-elements 2;
           description
             "Association to a group of interfaces configured for
             protection and used by a higher-layer-interface.";
         }

         leaf protection-operation-type {
           type enumeration {
             enum "non-revertive" {
               description
                 "In non revertive operation, the traffic does not
                 return to the working carrier termination interface if the switch requests
                 are terminated. "; terminated.";
               reference "ITU-T Rec. G.808.1";
             }
             enum "revertive" {
               description
                 "In revertive operation, the traffic always
                 returns to (or remains on) the working
                 carrier termination interface
                 if the switch requests are
                 terminated. "; terminated.";
               reference "ITU-T Rec. G.808.1";
             }
           }
           default "non-revertive";
           description
             "The type of protection operation, i.e. revertive
             or non-revertive operation.";
         }

         leaf-list working-entity  {
           when "../protection-operation-type = 'revertive'";
           type if:interface-ref;
           must "/if:interfaces/if:interface[if:name =  current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a working-entity must be
                'carrier-termination'.";
           }
           min-elements 1;
           description
             "The carrier terminations interfaces over which the traffic normally should
             be transported over when there is no need to use the
             protecting carrier termination."; interface.";
         }

         leaf revertive-wait-to-restore {
           when "../protection-operation-type = 'revertive'";
           type uint16;
           units "seconds";
           default "0";
           description
             "The time to wait before switching back to the working carrier termination
             interface if protection-operation-type is revertive.";
           reference "ITU-T Rec. G.808.1";
         }

         leaf-list radio-link-protection-members {
           type if:interface-ref;
           must "/if:interfaces/if:interface[if:name = current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a protection member must be
                'carrier-termination'.";
           }
           min-elements 2;
           description
             "Association to a group of carrier terminations
              configured for radio link protection and used in
              the radio link terminal.";
         }

         action protection-external-commands {
           input {
             leaf protection-external-command {
               type identityref {
                 base protection-external-commands;
               }
               description
                 "Execution of protection external commands for
                 trouble shooting purpose.";
             }
           }
         }
       }
     }

     /*
      * Radio Link Protection Groups - Operational state data nodes
      */

     container radio-link-protection-groups-state {
       config false;
       description
         "State data for radio link protected groups of
         carrier terminations in a radio link.";

       list radio-link-protection-group {
         key "name";
         description
           "List of protected groups of carrier terminations
           in a radio link.";
         leaf name hold-off-timer {
           type string; uint16;
           units "milliseconds";
           default "0";
           description
             "Name used for identification
             "Time interval after the detection of a fault and its
             confirmation as a condition requiring the radio
              link protection group.";
             switching procedure.";
           reference "ITU-T Rec. G.808.1";
         }

         leaf protection-status {
           type identityref {
             base protection-states;
           }
           description
             "Status of the protection, in a group of carrier
              terminations interfaces
              configured in a radio link protection mode.";
           reference "ITU-T Rec. G.808.1";
         }
       }
     }

     /*
      * XPIC & MIMO groups - Configuration data nodes
      */

     container xpic-pairs {
       if-feature xpic;
       description
         "Configuration of carrier termination pairs
          for operation in XPIC mode.";

       list xpic-pair

         action protection-external-commands {
         key "name";
         description
           "List of carrier termination pairs in XPIC mode.";

         leaf name
           input {
           type string;
           description
             "Name used for identification of the XPIC pair.";
         }
             leaf enabled {
           type boolean;
           default "false";
           description
             "Enable(true)/disable(false) XPIC";
         }

         leaf-list xpic-members protection-external-command {
               type if:interface-ref;
           must "/if:interfaces/if:interface[if:name = current()]"
             + "/if:type = 'mrl:carrier-termination'" identityref {
             description
               "The type of a xpic-member must be
               'carrier-termination'.";
           }
           min-elements 2;
           max-elements 2;
           description
             "Association to XPIC pairs used in the radio link
              terminal.";
         }
       }
                 base protection-external-commands;
               }

     container mimo-groups {
       if-feature mimo;
       description
         "Configuration of carrier terminations
         for operation in MIMO mode.";

       list mimo-group {
         key "name";
               description
           "List
                 "Execution of carrier terminations in MIMO mode.";

         leaf name {
           type string;
           description
             "Name used protection external commands for identification of the MIMO group.";
         }

         leaf enabled {
           type boolean;
           default "false";
           description
             "Enable(true)/disable(false) MIMO";
                 trouble shooting purpose.";
             }

         leaf-list mimo-members {
           type if:interface-ref;
           must "/if:interfaces/if:interface[if:name = current()]"
              + "/if:type = 'mrl:carrier-termination'" {
             description
               "The type of a mimo-member must be
                'carrier-termination'.";
           }
           min-elements 2;
           description
             "Association to a MIMO group if used in the radio
              link terminal.";
         }
       }
     }
   }

   <CODE ENDS>

5.

6.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer and the mandatory-to-implement secure
   transport is SSH [RFC6242].  The NETCONF access control model
   [RFC6536] provides the means to restrict access for particular
   NETCONF users to a pre-configured subset of all available NETCONF
   protocol operations and content.

   There are a number of data nodes defined in the YANG module which are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., <editconfig>)
   to these data nodes without proper protection can have a negative
   effect on network operations.

   The security considerations of [RFC7223] [RFC7223bis] also apply to this
   document.

6.

7.  IANA Considerations

   TBD.

7.

8.  References

7.1.

8.1.  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,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC7223]

   [RFC7223bis]
              Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 7223, DOI 10.17487/RFC7223, May 2014,
              <http://www.rfc-editor.org/info/rfc7223>. draft-bjorklund-netmod-rfc7223bis-00
              (work in progress), September 2017.

   [EN 302 217-2]
              ETSI, "Fixed Radio Systems; Characteristics and
              requirements for point to-point equipment and antennas;
              Part 2: Digital systems operating in frequency bands from
              1 GHz to 86 GHz; Harmonised Standard covering the
              essential requirements of article 3.2 of Directive
              2014/53/EU", EN 302 217-2 V3.1.1, May 2017.

7.2.

8.2.  Informative References

   [NMDA]     Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              Wilton, R. "Network Management Datastore Architecture",
              draft-ietf-netmod-revised-datastores-05 (work in
              progress), October 2017.

   [I-D.ahlberg-ccamp-microwave-radio-link]
              Ahlberg, J., Carlson, J., Lund, H., Olausson, T., Ye, M.,
              and M. Vaupotic, "Microwave Radio Link YANG Data Models",
              draft-ahlberg-ccamp-microwave-radio-link-01 (work in
              progress), May 2016.

   [I-D.ietf-ccamp-microwave-framework]
              Ahlberg, J., Contreras, L., Ye, M., Vaupotic, M.,
              Tantsura, J., Kawada, K., Li, X., Akiyoshi, I., and C.
              Bernardos, and D. Spreafico, "A framework for Management
              and Control of microwave and millimeter wave interface
              parameters",
              draft-ietf-ccamp-microwave-framework-01 draft-ietf-ccamp-microwave-framework-02
              (work in progress), June October 2017.

   [ONF-model] "Microwave Modeling - ONF Wireless Transport Group",
               May 2016.

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

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <http://www.rfc-editor.org/info/rfc6242>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012,
              <http://www.rfc-editor.org/info/rfc6536>.

Authors' Addresses

   Jonas Ahlberg
   Ericsson AB
   Lindholmspiren 11
   Goeteborg  417 56
   Sweden

   Email: jonas.ahlberg@ericsson.com

   Ye Min
   Huawei Technologies
   No.1899, Xiyuan Avenue
   Chengdu  611731
   P.R.China

   Email: amy.yemin@huawei.com

   Xi Li
   NEC Laboratories Europe
   Kurfursten-Anlage 36
   Heidelberg  69115
   Germany

   Email: Xi.Li@neclab.eu

   Koji Kawada
   NEC Corporation
   1753, Shimonumabe Nakahara-ku
   Kawasaki, Kanagawa  211-8666
   Japan

   Email: k-kawada@ah.jp.nec.com
   Carlos J. Bernardos
   Universidad Carlos III de Madrid
   Av. Universidad, 30
   Leganes, Madrid  28911
   Spain

   Email: cjbc@it.uc3m.es

   Daniela Spreafico
   Nokia - IT
   Via Energy Park, 14
   Vimercate (MI)  20871
   Italy

   Email: daniela.spreafico@nokia.com

   Marko Vaupotic
   Aviat Networks
   Motnica 9
   Trzin-Ljubljana  1236
   Slovenia

   Email: Marko.Vaupotic@Aviatnet.com