module openconfig-policy-forwarding {

    yang-version 1;

    namespace
      "http://openconfig.net/yang/policy-forwarding";

    prefix oc-pf;

    import openconfig-extensions {
      prefix oc-ext;
    }

    include openconfig-pf-forwarding-policies;
    include openconfig-pf-path-groups;
    include openconfig-pf-interfaces;

    organization "OpenConfig working group";

    contact
      "OpenConfig working group
www.openconfig.net";

    description
      "This module defines configuration and operational state data
relating to policy-based forwarding. Policy-based forwarding is
utilised when a system chooses how to forward packets (including
applying data-plane operations such as encapsulation or
decapsulation) based on policies other than destination L2 or L3
header. Typically, systems may implement:

- IP policy-based routing, where routing may be done based on the
  source plus destination of an IP packet; information within the
  L4 header; or some combination of both.
- Encapsulation or decapsulation based on certain policy
  information - for example, matching particular IP destinations
  and decapsulating GRE headers.
- Class-based selection of egress routes - such as class-based
  selection of an egress MPLS path.

The policies that are defined in this model are applied to a
particular ingress context of a network element (e.g., interface)
and are defined to apply following other interface policy such as
QoS classification and access control lists.

This module defines:

- policy-forwarding
|
|--- policies
|    |-- policy
|        |-- [match criteria]    How packets are defined to
|        |                       match policy.
|        |-- [forwarding-action] How packets matching should
|                                 be forwarded.
|--- interfaces
|    |-- interfaces
|        | -- apply-forwarding-policy  Forwarding policy to
|                                      used on the interface.
|--- path-selection-groups
    |-- path-selection-group     A group of forwarding resources
				 that are grouped for purposes
				 of next-hop selection.

A forwarding-policy specifies the match criteria that it intends
to use to determine the packets that it reroutes - this may
consist of a number of criteria, such as DSCP. The action of the
policy results in a forwarding action being applied to matching
packets. For example, decapsulating the packet from a GRE header.
In order to enact the policy based on particular interfaces - the
forwarding-policy is applied to an interface via referencing it
within an 'apply-forwarding-policy' statement associated with an
interface.

In some cases (e.g., Class-Based Tunnel Selection) the forwarding
action does not resolve to a single egress action, and rather
normal forwarding rules are to be applied but considering a subset
of forwarding resources. In these cases, a path-selection-group
can be created, referencing the subset of forwarding paths that
should be used for the egress selection. In the case that a subset
of MPLS LSPs are eligible for, say, DSCP 46 marked packets, a
path-selection-group is created, referencing the subset of LSPs.
The forwarding action of the corresponding policy is set to
PATH_GROUP and references the configured group of LSPs.";

    revision "2022-01-25" {
      description
        "Add GUE and MPLS-in-UDP decapsulation actions.";
      reference
        "0.5.0";

    }

    revision "2021-08-06" {
      description
        "Update path to the network instance action to allow references
to other NIs.";
      reference
        "0.4.0";

    }

    revision "2021-05-19" {
      description
        "Add a VRF selection policy type, and means to apply the
policy.";
      reference
        "0.3.0";

    }

    revision "2018-11-21" {
      description
        "Add OpenConfig module metadata extensions.";
      reference
        "0.2.1";

    }

    revision "2017-06-21" {
      description
        "Amend policy forwarding model based on ACL changes.";
      reference
        "0.2.0";

    }

    revision "2017-02-28" {
      description
        "Initial public release of policy forwarding.";
      reference
        "0.1.0";

    }

    revision "2016-11-08" {
      description "Initial revision.";
      reference
        "0.0.1";

    }

    oc-ext:openconfig-version "0.5.0";
    oc-ext:regexp-posix;
    oc-ext:catalog-organization "openconfig";
    oc-ext:origin "openconfig";

    grouping policy-forwarding-top {
      description
        "Top-level grouping for Policy Forwarding";
      container policy-forwarding {
        description
          "Configuration and operational state relating to policy-forwarding within
a network instance.";
        uses pf-forwarding-policy-structural;

        uses pf-interfaces-structural;

        uses pf-path-groups-structural;
      }  // container policy-forwarding
    }  // grouping policy-forwarding-top
  }  // module openconfig-policy-forwarding