module bbf-sub-interfaces {

    yang-version 1.1;

    namespace
      "urn:bbf:yang:bbf-sub-interfaces";

    prefix bbf-subif;

    import ietf-interfaces {
      prefix if;
    }
    import bbf-yang-types {
      prefix bbf-yang;
    }
    import bbf-if-type {
      prefix bbfift;
    }

    organization
      "Broadband Forum <https://www.broadband-forum.org>
Common YANG Work Area";

    contact
      "Comments or questions about this Broadband Forum YANG module
should be directed to <mailto:help@broadband-forum.org>.

Editor:      Nick Hancock, ADTRAN

Editor:      Ludwig Pauwels, Nokia

PS Leader:   Joey Boyd, ADTRAN

PS Leader:   Sowrirajan Padmanabhan, Nokia

WA Director: Joey Boyd, ADTRAN

WA Director: Sven Ooghe, Nokia";

    description
      "This module contains a collection of YANG definitions for
supporting the Broadband Forum requirements on the management of
sub-interfaces as applicable to access network equipment. As
such, this module is specific to access network equipment (e.g.,
BBF-specified Access Nodes and FTTdp DPUs).

Specifically, this module augments an interface with
sub-interface-specific frame processing configuration.

Copyright (c) 2017-2021, Broadband Forum

Redistribution and use in source and binary forms, with or
without modification, are permitted provided that the following
conditions are met:

1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above
   copyright notice, this list of conditions and the following
   disclaimer in the documentation and/or other materials
   provided with the distribution.

3. Neither the name of the copyright holder nor the names of its
   contributors may be used to endorse or promote products
   derived from this software without specific prior written
   permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

The above license is used as a license under copyright only.
Please reference the Forum IPR Policy for patent licensing terms
<https://www.broadband-forum.org/ipr-policy>.

Any moral rights which are necessary to exercise under the above
license grant are also deemed granted under this license.

This version of this YANG module is part of TR-383a4; see
the TR itself for full legal notices.";

    revision "2021-06-02" {
      description
        "Amendment 4.
* Approval Date:    2021-06-02.
* Publication Date: 2021-06-02.";
      reference
        "TR-383a4: Common YANG Modules
        	  <https://www.broadband-forum.org/technical/download/
        		   TR-383_Amendment-4.pdf>";

    }

    revision "2020-10-13" {
      description
        "Amendment 3.
* Approval Date:    2020-10-13.
* Publication Date: 2020-10-13.";
      reference
        "TR-383a3: Common YANG Modules
        	  <https://www.broadband-forum.org/technical/download/
        		   TR-383_Amendment-3.pdf>";

    }

    revision "2018-12-03" {
      description
        "Amendment 2.
* Approval Date:    2018-12-03.
* Publication Date: 2018-12-03.";
      reference
        "TR-383a2: Common YANG Modules
        	<https://www.broadband-forum.org/technical/download/
        		 TR-383_Amendment-2.pdf>";

    }

    revision "2017-05-08" {
      description
        "Initial revision.
* Approval Date:    see revision date above.
* Publication Date: 2017-06-02.";
      reference
        "TR-383: Common YANG Modules
        	<https://www.broadband-forum.org/technical/download/
        		 TR-383.pdf>";

    }


    feature tag-rewrites {
      description
        "This feature indicates whether the network element supports the
flexible rewrite functionality specifying flexible tag
rewrites.";
    }

    augment /if:interfaces/if:interface {
      when
        "derived-from-or-self(if:type, 'bbfift:sub-interface')" {
        description
          "Common data that defines the relationship between the
sub-interface and its lower-layer interface.";
      }
      description
        "Add a reference pointing to a lower-layer interface to those
interfaces that are of the type sub-interface.";
      container subif-lower-layer {
        description
          "Links the sub-interface to a lower-layer interface.";
        leaf interface {
          type if:interface-ref;
          mandatory true;
          description
            "References the lower-layer interface.";
        }
      }  // container subif-lower-layer

      choice frame-processing {
        description
          "Configuration of frame processing.

Multiple alternatives can be defined. They all have in common
that the definition of the frame processing is relative to
the lower layer interface configured in leaf
'subif-lower-layer'.

For example, if there is configuration for ingress frame
processing, then this means that frames received on the
referenced lower layer interface are subject to evaluation
using the match criteria configured for this sub-interface.
Not configuring any frame processing case implies that there
are no ingress match criteria to select frames received from
the lower layer interface into this sub-interface, and hence
this sub-interface will not have to process any ingress
frame.";
        container inline-frame-processing {
          description
            "The frame processing refers to both directions:
- Ingress, which refers to frames received from the
  lower-layer interface.
- Egress, which refers to frames received from a higher
  layer of the interface stack, or from a forwarder, and
  to be transmitted to the lower-layer of the interface
  stack.
- In the ingress direction classification criteria
  identify whether a received frame shall be offered to
  this sub-interface.
- For both the ingress and egress direction, rewrite =
  tag manipulations can be supported.";
          container ingress-rule {
            description
              "The match used to classify ingress frames to this
sub-interface, and it allows to specify re-tagging
actions before sending it to higher layers in the
interface stack or to a forwarder.";
            list rule {
              key "name";
              min-elements 1;
              description
                "A rule contains a classification and for frames that
match this classification it specifies an ingress tag
manipulation action.

The definition is: first match, then stop searching
for matches with other rules, then execute the
ingress-rewrite actions specified in this rule.";
              leaf name {
                type bbf-yang:string-ascii64;
                description "The rule name.";
              }

              leaf priority {
                type uint16 {
                  range "1..max";
                }
                mandatory true;
                description
                  "This field indicates the priority for applying the
match criteria of this rule against the priority of
match criteria of other rules of this and other
sub-interfaces on the same parent-interface.

The higher the value, the lower the priority, i.e.
priority 1 is the highest priority.

Note that priorities of rules do not have to be
unique within a lower-layer interface. For example,
if there is no overlap in the 'flexible-match'
criteria of of a different sub-interfaces having
the same lower layer interface, then the
configuration is still unambiguous. If different
sub-interfaces with the same lower layer interface
are configured such that there is overlap between
their flexible-match criteria, then unambiguity is
achieved by configuring the rules with different
priorities. If the priority is configured equal,
despite having overlapping match criteria, then the
device's behavior is undefined, meaning, it can be
different in different devices, even more it can be
different in single device over time.";
              }

              container flexible-match {
                description
                  "This container provides a generic framework to
specify match criteria for frame fields. Specific
match criteria shall be provided using augments in
a context dependent way, e.g. match criteria can be
augmented for VLAN tagged frames, or in another
context match criteria can be augmented for MPLS
frames.";
              }  // container flexible-match

              container ingress-rewrite {
                if-feature tag-rewrites;
                description
                  "Ingress rewrite refers to the supported tag
manipulations before the frame is offered to a
higher layer interface or to a forwarder.";
              }  // container ingress-rewrite
            }  // list rule
          }  // container ingress-rule

          container egress-rewrite {
            if-feature tag-rewrites;
            description
              "Egress refers to frames sent from the sub-interface
towards the the lower-layer in the interface stack,
i.e. in the direction of the physical interface.
Rewrite refers to the supported tag manipulations.";
          }  // container egress-rewrite
        }  // container inline-frame-processing
      }  // choice frame-processing
    }
  }  // module bbf-sub-interfaces