Network Working Group D. Kumar
Internet-Draft Cisco
Intended status: Standards Track M. Wang
Expires: September 2, 2016 Q. Wu
Huawei
R. Rahman
Cisco
March 1, 2016

Generic YANG Data Model for Connection Less Operations, Administration, and Maintenance(OAM) protocols
draft-kumar-lime-yang-connectionless-oam-00

Abstract

This document presents a base YANG Data model for connectionless OAM protocols. It provides a technology-independent abstraction of key OAM constructs for connectionless protocols. Based model presented here can be extended to include technology specific details. This is leading to uniformity between OAM protocols and support nested OAM workflows (i.e., performing OAM functions at different or same levels through a unified interface).

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 September 2, 2016.

Copyright Notice

Copyright (c) 2016 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. Introduction

Operations, Administration, and Maintenance (OAM) are important networking functions that allow operators to:

  1. Monitor networks connections (Connectivity Verification, Continuity Check).
  2. Troubleshoot failures (Fault verification and localization).
  3. Monitor Performance

An overview of OAM tools is presented at [RFC7276].

Ping and Traceroute [RFC792], [RFC4443] are well-known fault verification and isolation tools, respectively, for IP networks. Over the years, different technologies have developed similar tools for similar purposes.

In this document, we presents a base YANG Data model for connectionless OAM protocols which supports generic continuity or reachability check, and path discovery. The generic YANG model for connectionless OAM is designed such that it can be extended to cover various connectionless technologies. Technology dependent nodes and RPC (remote process call) commands are defined in technology specific YANG models, which use and extend the base model defined here.

2. Conventions used in this document

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].

The following terms are defined in [RFC6241] and are not redefined here:

The following terms are defined in [RFC6020] and are not redefined here:

The terminology for describing YANG data models is found in [RFC6020].

2.1. Tree Diagrams

A simplified graphical representation of the data model is used in this document. The meaning of the symbols in these diagrams is as follows:

<status> <flags> <name> <opts> <type>

<status> is one of:
     +  for current
     x  for deprecated
     o  for obsolete


<flags> is one of:

    rw for configuration data 
    ro for non-configuration data
    -x for rpcs
    -n for notifications


<name> is the name of the node

Each node is printed as:

<opts> is one of:

     ?  for an optional leaf or choice
     !  for a presence container
     *  for a leaf-list or list
     [<keys>] for a list's keys

<type> is the name of the type for leafs and leaf-lists

If the node is augmented into the tree from another module, its name is printed as <prefix>:<name>.

3. Overview of the Connectionless OAM Model

At the top of the Model there is Multiple test-point-location-list keyed using test point location type. Under test-point-location-list, there is one or more test-point-locations. Each test-point-location is associated with vrf, oam-layers, tools, and technology. The vrf is used to describe the corresponding network instance. The technology indicate oam technology details. The tools is used to describe oam tools supported. The oam-layers is used to indicate relation of test point with other test points. The level in oam-layers indicate whether related oam test point is client layer, server layer or same or stiched layer. The Model is augmented to /nd:networks/nd:network/nd:node. oper is also defined at top of the Model to provide continuity-check common statistics. grouping is also defined for common per session continuity-check statistics.

Under test-point-locations, there are tp-addresses, technology type, OAM tool which describe the attriburtes associated with test-point.

3.1. TP address

In connectionless OAM, the tp address is defined with the following type:

3.2. tools

In connectionless OAM, the tools attribute is used to describe a toolset for fault detection and isolation, and for performance measurement. And it can serve as a constraint condition when the base model be extended to specific OAM technology. For example, to fulfill the icmp ping configuration, the "../coam:tools-ip/coam:rfc792" should be set to "true", and then the lime base model should be augmented with icmp ping specific details.

3.3. OAM-layers

OAM-layers is referred to a list of OAM layers above and below that are related to current test point. This allow users to easily navigate up and down to efficiently troubleshoot a connectivity issue. For example, there is a defect in the upstream path of the testpoint, the upstream path belongs to server layer LSP and the level is set to "-1", the downstream path of the test point belongs to client layer LSP and the level is set to "1", then we can stitch server layer LSP and client layer LSP at different level and track defect along this path. In another case, if the upstream path and downstream path of the test point is in the same level, the level is set to "0". The snippet below depicts an example of OAM layers.

        
             list oam-layers {
               key "index";
               leaf index {
                  type uint16 {
                     range "0..65535";
                  }
               }
               leaf level {
                   type int32 {
                        range "-1..1";
                   }
                   description
                     "Level";
               }
               ordered-by user;
               description
                  "list of related oam layers.";
             }
             

3.4. rpc definitions

The rpc model facilitates issuing commands to a NETCONF server (in this case to the device that need to execute the OAM command) and obtaining a response.

In this document, we summarize the common OAM functions and define the generic rpc commands: continuity-check and path-discovery. In practice, these commands are supported by corresponding technology- specific OAM tools [RFC7276]. For example, for the IP OAM model, the continuity-check rpc corresponds to the IP Ping, while the path- discovery rpc command corresponds to IP Traceroute.

Note that the rpc command presented in this document is the base building block, which is used to derive a model for a technology-specific OAM(i.e., icmp ping, lsp ping), the base building block should be extended with corresponding technology specific parameters.

     continuity-check:
    rpc continuity-check {
          if-feature continuity-check;
          description
            "Generates continuity-check as per RFC7276.";
          input {
            container destination-tp {
              uses tp-address;
            }
            uses session-type;
            leaf source-interface {
              type if:interface-ref;
              mandatory false;
            }
            leaf outbound-interface {
              type if:interface-ref;
              mandatory false;
            }
            leaf count {
              type uint32;
              default "5";
              mandatory false;
            }
            leaf vrf {
              type rt:routing-instance-ref;
              mandatory false;
            }
            leaf ttl {
              type uint8;
              default "255";
              mandatory false;
            }
            leaf packet-size {
              type uint32 {
                range "64..10000";
              }
              default "64";
              mandatory false;
              description
                "Size of ping echo request packets, in octets";
            }
          }
          output {
            list error-code-list {
              key "response-index";
              leaf response-index {
                type uint32;
              }
              leaf status-code {
                type int32;
                description
                  "error code is ";
              }
              leaf status-sub-code {
                type uint8;
                mandatory false;
              }
            }
            leaf tx-packt-count {
              type oam-counter32;
              mandatory false;
              description
                "Transmitted Packet count";
            }
            leaf rx-packet-count {
              type oam-counter32;
              mandatory false;
              description
                "Received packet count";
            }
            leaf min-delay {
              type oam-counter32;
              mandatory false;
              units milliseconds;
              description
                "Delay is specified in milliseconds";
            }
            leaf average-delay {
              type oam-counter32;
              mandatory false;
              units millisecond;
              description
                "average delay in milliseconds";
            }
            leaf max-delay {
              type oam-counter32;
              mandatory false;
              units millisecond;
              description
                "Maximum delay in milliseconds";
            }
          }
        }

   Path discovery:
        rpc path-discovery {
          description
            "";
          input {
            container destination-tp {
              uses tp-address;
            }
            uses session-type;
            leaf source-interface {
              type if:interface-ref;
              mandatory false;
            }
            leaf outbound-interface {
              type if:interface-ref;
              mandatory false;
            }
            leaf vrf {
              type rt:routing-instance-ref;
              mandatory false;
            }
            leaf max-ttl {
              type uint8;
              default "255";
              mandatory false;
            }
          }
          output {
            list response-list {
              key "response-index";
              leaf response-index {
                type uint32;
              }
              leaf status-code {
                type int32;
                description
                  "error code is ";
              }
              leaf status-sub-code {
                type uint8;
                mandatory false;
              }
              leaf hop-cnt {
                type uint8;
                description
                  "";
              }
              container destination-tp {
                uses tp-address;
              }
              leaf min-delay {
                type oam-counter32;
                mandatory false;
                units milliseconds;
                description
                  "Delay is specified in milliseconds";
              }
              leaf average-delay {
                type oam-counter32;
                mandatory false;
                units millisecond;
                description
                  "average delay in milliseconds";
              }
              leaf max-delay {
                type oam-counter32;
                mandatory false;
                units millisecond;
                description
                  "Maximum delay in milliseconds";
              }
            }
           }
        }

Snippet of data hierarchy related to rpc calls

3.5. Relation with other OAM YANG Model

In this document we define a generic YANG model for connectionless OAM protocols. The YANG model defined here is generic such that other technologies can extend it for technology specific needs. The Generic YANG model acts as the root for other OAM YANG models. This allows users to traverse between different OAM protocols at ease through a uniform API set. The Generic YANG model for OAM provides a framework where technology- specific YANG models can choose to inherit constructs from the base YANG models without needing to redefine them within the sub-technology.

3.6. OAM data hierarchy

The complete data hierarchy related to the OAM YANG model is presented below.

module: ietf-connectionless-oam
   +--ro oper {continuity-check}?
      +--ro cc-ipv4-sessions-statistics
      |  +--ro cc-session-statistics
      |     +--ro session-count?              uint32
      |     +--ro session-up-count?           uint32
      |     +--ro session-down-count?         uint32
      |     +--ro session-admin-down-count?   uint32
      +--ro cc-ipv6-sessions-statistics
         +--ro cc-session-statistics
            +--ro session-count?              uint32
            +--ro session-up-count?           uint32
            +--ro session-down-count?         uint32
            +--ro session-admin-down-count?   uint32
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-ipv4-location-list {connection-less}?
      +--rw test-point-locations* [ipv4-location]
         +--rw ipv4-location          inet:ipv4-address
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?  inet:ip-address
               |     |  +--rw pw-id?              uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-ipv6-location-list {connection-less}?
      +--rw test-point-locations* [ipv6-location]
         +--rw ipv6-location          inet:ipv6-address
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-tunnel-address-location-list {connection-less}?
      +--rw test-point-locations* [tunnel-location]
         +--rw tunnel-location        uint32
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-mac-address-location-list {connection-less}?
      +--rw test-point-locations* [mac-address-location]
         +--rw mac-address-location    yang:mac-address
         +--rw vrf?                    rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?            yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?           inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?           inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?         inet:ip-address
         |  |  +--rw dst-ip-address?         inet:ip-address
         |  |  +--rw Interface?              if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?               fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?              inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                    inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?       uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?               uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?      inet:ip-address
         |  |     |  +--rw pw-id?                  uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?    uint32
         |  |     |  +--rw sender-ve-id?           uint32
         |  |     |  +--rw receiver-ve-id?         uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?              inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                 string
         |  +--:(tlv-address)
         |     +--rw tlv-type?               int16
         |     +--rw tlv-len?                int16
         |     +--rw tlv-value?              binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?              empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?              string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?             empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                 boolean
         |  |  +--rw rfc4443?                boolean
         |  |  +--rw rfc4884?                boolean
         |  |  +--rw rfc5837?                boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?                boolean
         |  |  +--rw rfc5881?                boolean
         |  |  +--rw rfc5882?                boolean
         |  |  +--rw rfc5883?                boolean
         |  |  +--rw rfc5884?                boolean
         |  |  +--rw rfc5885?                boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?                boolean
         |  |  +--rw rfc4687?                boolean
         |  |  +--rw rfc4950?                boolean
         |  |  +--rw mpls-rfc5884?           boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?                boolean
         |  |  +--rw rfc6426?                boolean
         |  |  +--rw rfc6435?                boolean
         |  |  +--rw rfc6374?                boolean
         |  |  +--rw rfc6375?                boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?                boolean
         |     +--rw pw_rfc5885?             boolean
         |     +--rw rfc6423?                boolean
         |     +--rw rfc6310?                boolean
         |     +--rw rfc7023?                boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-ip-prefix-location-list {connection-less}?
      +--rw test-point-locations* [ip-prefix-location]
         +--rw ip-prefix-location     inet:ip-prefix
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-route-dist-location-list {connection-less}?
      +--rw test-point-locations* [route-dist-location]
         +--rw route-dist-location    uint32
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   net:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-group-ip-address-location-list {connection-less}?
      +--rw test-point-locations* [group-ip-address-location]
         +--rw group-ip-address-location    IP-Multicast-Group-Address
         +--rw vrf?                         rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?                 yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?                inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?                inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?              inet:ip-address
         |  |  +--rw dst-ip-address?              inet:ip-address
         |  |  +--rw Interface?                   if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?                    fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?                   inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                         inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?            uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?                    uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?           inet:ip-address
         |  |     |  +--rw pw-id?                       uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?         uint32
         |  |     |  +--rw sender-ve-id?                uint32
         |  |     |  +--rw receiver-ve-id?              uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?                   inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                      string
         |  +--:(tlv-address)
         |     +--rw tlv-type?                    int16
         |     +--rw tlv-len?                     int16
         |     +--rw tlv-value?                   binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?                   empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?                   string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?                  empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                      boolean
         |  |  +--rw rfc4443?                     boolean
         |  |  +--rw rfc4884?                     boolean
         |  |  +--rw rfc5837?                     boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?                     boolean
         |  |  +--rw rfc5881?                     boolean
         |  |  +--rw rfc5882?                     boolean
         |  |  +--rw rfc5883?                     boolean
         |  |  +--rw rfc5884?                     boolean
         |  |  +--rw rfc5885?                     boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?                     boolean
         |  |  +--rw rfc4687?                     boolean
         |  |  +--rw rfc4950?                     boolean
         |  |  +--rw mpls-rfc5884?                boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?                     boolean
         |  |  +--rw rfc6426?                     boolean
         |  |  +--rw rfc6435?                     boolean
         |  |  +--rw rfc6374?                     boolean
         |  |  +--rw rfc6375?                     boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?                     boolean
         |     +--rw pw_rfc5885?                  boolean
         |     +--rw rfc6423?                     boolean
         |     +--rw rfc6310?                     boolean
         |     +--rw rfc7023?                     boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-as-number-location-list {connection-less}?
      +--rw test-point-locations* [as-number-location]
         +--rw as-number-location     inet:as-number
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
augment /nd:networks/nd:network/nd:node:
   +--rw test-point-lsp-id-location-list {connection-less}?
      +--rw test-point-locations* [lsp-id-location]
         +--rw lsp-id-location        string
         +--rw vrf?                   rt:routing-instance-ref
         +--rw (tp-address)?
         |  +--:(mac-address)
         |  |  +--rw mac-address?           yang:mac-address
         |  +--:(ipv4-address)
         |  |  +--rw ipv4-address?          inet:ipv4-address
         |  +--:(ipv6-address)
         |  |  +--rw ipv6-address?          inet:ipv6-address
         |  +--:(src-dst-address)
         |  |  +--rw src-ip-address?        inet:ip-address
         |  |  +--rw dst-ip-address?        inet:ip-address
         |  |  +--rw Interface?             if:interface-ref
         |  +--:(fec)
         |  |  +--rw fec-type?              fec-type
         |  |  +--rw (fec-value)?
         |  |     +--:(ip-prefix)
         |  |     |  +--rw ip-prefix?             inet:ip-prefix
         |  |     +--:(bgp)
         |  |     |  +--rw bgp?                   inet:ip-prefix
         |  |     +--:(tunnel)
         |  |     |  +--rw tunnel-interface?      uint32
         |  |     +--:(l3vpn)
         |  |     |  +--rw l3vpn-id?              uint32
         |  |     +--:(pw)
         |  |     |  +--rw remote-pe-address?     inet:ip-address
         |  |     |  +--rw pw-id?                 uint32
         |  |     +--:(vpls)
         |  |     |  +--rw route-distinguisher?   uint32
         |  |     |  +--rw sender-ve-id?          uint32
         |  |     |  +--rw receiver-ve-id?        uint32
         |  |     +--:(mpls-mldp)
         |  |        +--rw (root-address)?
         |  |           +--:(ip-address)
         |  |           |  +--rw source-address?   inet:ip-address
         |  |           |  +--rw group-ip-address? IP-Multicast-Group-Address
         |  |           +--:(vpn)
         |  |           |  +--rw as-number?             inet:as-number
         |  |           +--:(global-id)
         |  |              +--rw lsp-id?                string
         |  +--:(tlv-address)
         |     +--rw tlv-type?              int16
         |     +--rw tlv-len?               int16
         |     +--rw tlv-value?             binary
         +--rw (technology)?
         |  +--:(technology-null)
         |  |  +--rw tech-null?             empty
         |  +--:(technology-string)
         |     +--rw ipv4-icmp?             string
         +--rw (tools)?
         |  +--:(tools-empty)
         |  |  +--rw tools-null?            empty
         |  +--:(tools-ip)
         |  |  +--rw rfc792?                boolean
         |  |  +--rw rfc4443?               boolean
         |  |  +--rw rfc4884?               boolean
         |  |  +--rw rfc5837?               boolean
         |  +--:(tools-bfd)
         |  |  +--rw rfc5880?               boolean
         |  |  +--rw rfc5881?               boolean
         |  |  +--rw rfc5882?               boolean
         |  |  +--rw rfc5883?               boolean
         |  |  +--rw rfc5884?               boolean
         |  |  +--rw rfc5885?               boolean
         |  +--:(tools-mpls)
         |  |  +--rw rfc4379?               boolean
         |  |  +--rw rfc4687?               boolean
         |  |  +--rw rfc4950?               boolean
         |  |  +--rw mpls-rfc5884?          boolean
         |  +--:(tools-mpls-tp)
         |  |  +--rw rfc6428?               boolean
         |  |  +--rw rfc6426?               boolean
         |  |  +--rw rfc6435?               boolean
         |  |  +--rw rfc6374?               boolean
         |  |  +--rw rfc6375?               boolean
         |  +--:(tools-pw)
         |     +--rw rfc5085?               boolean
         |     +--rw pw_rfc5885?            boolean
         |     +--rw rfc6423?               boolean
         |     +--rw rfc6310?               boolean
         |     +--rw rfc7023?               boolean
         +--rw oam-layers* [index]
            +--rw index                  uint16
            +--rw level?                 int32
            +--rw (tp-address)?
               +--:(mac-address)
               |  +--rw mac-address?           yang:mac-address
               +--:(ipv4-address)
               |  +--rw ipv4-address?          inet:ipv4-address
               +--:(ipv6-address)
               |  +--rw ipv6-address?          inet:ipv6-address
               +--:(src-dst-address)
               |  +--rw src-ip-address?        inet:ip-address
               |  +--rw dst-ip-address?        inet:ip-address
               |  +--rw Interface?             if:interface-ref
               +--:(fec)
               |  +--rw fec-type?              fec-type
               |  +--rw (fec-value)?
               |     +--:(ip-prefix)
               |     |  +--rw ip-prefix?             inet:ip-prefix
               |     +--:(bgp)
               |     |  +--rw bgp?                   inet:ip-prefix
               |     +--:(tunnel)
               |     |  +--rw tunnel-interface?      uint32
               |     +--:(l3vpn)
               |     |  +--rw l3vpn-id?              uint32
               |     +--:(pw)
               |     |  +--rw remote-pe-address?     inet:ip-address
               |     |  +--rw pw-id?                 uint32
               |     +--:(vpls)
               |     |  +--rw route-distinguisher?   uint32
               |     |  +--rw sender-ve-id?          uint32
               |     |  +--rw receiver-ve-id?        uint32
               |     +--:(mpls-mldp)
               |        +--rw (root-address)?
               |           +--:(ip-address)
               |           |  +--rw source-address?   inet:ip-address
               |           |  +--rw group-ip-address? IP-Multicast-Group-Address
               |           +--:(vpn)
               |           |  +--rw as-number?             inet:as-number
               |           +--:(global-id)
               |              +--rw lsp-id?                string
               +--:(tlv-address)
                  +--rw tlv-type?              int16
                  +--rw tlv-len?               int16
                  +--rw tlv-value?             binary
rpcs:
   +---x continuity-check {continuity-check}?
   |  +---w input
   |  |  +---w destination-tp
   |  |  |  +---w (tp-address)?
   |  |  |     +--:(mac-address)
   |  |  |     |  +---w mac-address?           yang:mac-address
   |  |  |     +--:(ipv4-address)
   |  |  |     |  +---w ipv4-address?          inet:ipv4-address
   |  |  |     +--:(ipv6-address)
   |  |  |     |  +---w ipv6-address?          inet:ipv6-address
   |  |  |     +--:(src-dst-address)
   |  |  |     |  +---w src-ip-address?        inet:ip-address
   |  |  |     |  +---w dst-ip-address?        inet:ip-address
   |  |  |     |  +---w Interface?             if:interface-ref
   |  |  |     +--:(fec)
   |  |  |     |  +---w fec-type?              fec-type
   |  |  |     |  +---w (fec-value)?
   |  |  |     |     +--:(ip-prefix)
   |  |  |     |     |  +---w ip-prefix?             inet:ip-prefix
   |  |  |     |     +--:(bgp)
   |  |  |     |     |  +---w bgp?                   inet:ip-prefix
   |  |  |     |     +--:(tunnel)
   |  |  |     |     |  +---w tunnel-interface?      uint32
   |  |  |     |     +--:(l3vpn)
   |  |  |     |     |  +---w l3vpn-id?              uint32
   |  |  |     |     +--:(pw)
   |  |  |     |     |  +---w remote-pe-address?     inet:ip-address
   |  |  |     |     |  +---w pw-id?                 uint32
   |  |  |     |     +--:(vpls)
   |  |  |     |     |  +---w route-distinguisher?   uint32
   |  |  |     |     |  +---w sender-ve-id?          uint32
   |  |  |     |     |  +---w receiver-ve-id?        uint32
   |  |  |     |     +--:(mpls-mldp)
   |  |  |     |        +---w (root-address)?
   |  |  |     |           +--:(ip-address)
   |  |  |     |           |  +---w source-address?   inet:ip-address
   |  |  |     |           |  +---w group-ip-address? IP-Multicast-Group-Address
   |  |  |     |           +--:(vpn)
   |  |  |     |           |  +---w as-number?             inet:as-number
   |  |  |     |           +--:(global-id)
   |  |  |     |              +---w lsp-id?                string
   |  |  |     +--:(tlv-address)
   |  |  |        +---w tlv-type?              int16
   |  |  |        +---w tlv-len?               int16
   |  |  |        +---w tlv-value?             binary
   |  |  +---w session-type-enum?    enumeration
   |  |  +---w source-interface?     if:interface-ref
   |  |  +---w outbound-interface?   if:interface-ref
   |  |  +---w count?                uint32
   |  |  +---w vrf?                  rt:routing-instance-ref
   |  |  +---w ttl?                  uint8
   |  |  +---w packet-size?          uint32
   |  +--ro output
   |     +--ro error-code-list* [response-index]
   |     |  +--ro response-index     uint32
   |     |  +--ro status-code?       int32
   |     |  +--ro status-sub-code?   uint8
   |     +--ro tx-packt-count?    oam-counter32
   |     +--ro rx-packet-count?   oam-counter32
   |     +--ro min-delay?         oam-counter32
   |     +--ro average-delay?     oam-counter32
   |     +--ro max-delay?         oam-counter32
   +---x path-discovery
      +---w input
      |  +---w destination-tp
      |  |  +---w (tp-address)?
      |  |     +--:(mac-address)
      |  |     |  +---w mac-address?           yang:mac-address
      |  |     +--:(ipv4-address)
      |  |     |  +---w ipv4-address?          inet:ipv4-address
      |  |     +--:(ipv6-address)
      |  |     |  +---w ipv6-address?          inet:ipv6-address
      |  |     +--:(src-dst-address)
      |  |     |  +---w src-ip-address?        inet:ip-address
      |  |     |  +---w dst-ip-address?        inet:ip-address
      |  |     |  +---w Interface?             if:interface-ref
      |  |     +--:(fec)
      |  |     |  +---w fec-type?              fec-type
      |  |     |  +---w (fec-value)?
      |  |     |     +--:(ip-prefix)
      |  |     |     |  +---w ip-prefix?             inet:ip-prefix
      |  |     |     +--:(bgp)
      |  |     |     |  +---w bgp?                   inet:ip-prefix
      |  |     |     +--:(tunnel)
      |  |     |     |  +---w tunnel-interface?      uint32
      |  |     |     +--:(l3vpn)
      |  |     |     |  +---w l3vpn-id?              uint32
      |  |     |     +--:(pw)
      |  |     |     |  +---w remote-pe-address?     inet:ip-address
      |  |     |     |  +---w pw-id?                 uint32
      |  |     |     +--:(vpls)
      |  |     |     |  +---w route-distinguisher?   uint32
      |  |     |     |  +---w sender-ve-id?          uint32
      |  |     |     |  +---w receiver-ve-id?        uint32
      |  |     |     +--:(mpls-mldp)
      |  |     |        +---w (root-address)?
      |  |     |           +--:(ip-address)
      |  |     |           |  +---w source-address?   inet:ip-address
      |  |     |           |  +---w group-ip-address? IP-Multicast-Group-Address
      |  |     |           +--:(vpn)
      |  |     |           |  +---w as-number?             inet:as-number
      |  |     |           +--:(global-id)
      |  |     |              +---w lsp-id?                string
      |  |     +--:(tlv-address)
      |  |        +---w tlv-type?              int16
      |  |        +---w tlv-len?               int16
      |  |        +---w tlv-value?             binary
      |  +---w session-type-enum?    enumeration
      |  +---w source-interface?     if:interface-ref
      |  +---w outbound-interface?   if:interface-ref
      |  +---w vrf?                  rt:routing-instance-ref
      |  +---w max-ttl?              uint8
      +--ro output
         +--ro response-list* [response-index]
            +--ro response-index     uint32
            +--ro status-code?       int32
            +--ro status-sub-code?   uint8
            +--ro hop-cnt?           uint8
            +--ro destination-tp
            |  +--ro (tp-address)?
            |     +--:(mac-address)
            |     |  +--ro mac-address?           yang:mac-address
            |     +--:(ipv4-address)
            |     |  +--ro ipv4-address?          inet:ipv4-address
            |     +--:(ipv6-address)
            |     |  +--ro ipv6-address?          inet:ipv6-address
            |     +--:(src-dst-address)
            |     |  +--ro src-ip-address?        inet:ip-address
            |     |  +--ro dst-ip-address?        inet:ip-address
            |     |  +--ro Interface?             if:interface-ref
            |     +--:(fec)
            |     |  +--ro fec-type?              fec-type
            |     |  +--ro (fec-value)?
            |     |     +--:(ip-prefix)
            |     |     |  +--ro ip-prefix?             inet:ip-prefix
            |     |     +--:(bgp)
            |     |     |  +--ro bgp?                   inet:ip-prefix
            |     |     +--:(tunnel)
            |     |     |  +--ro tunnel-interface?      uint32
            |     |     +--:(l3vpn)
            |     |     |  +--ro l3vpn-id?              uint32
            |     |     +--:(pw)
            |     |     |  +--ro remote-pe-address?     inet:ip-address
            |     |     |  +--ro pw-id?                 uint32
            |     |     +--:(vpls)
            |     |     |  +--ro route-distinguisher?   uint32
            |     |     |  +--ro sender-ve-id?          uint32
            |     |     |  +--ro receiver-ve-id?        uint32
            |     |     +--:(mpls-mldp)
            |     |        +--ro (root-address)?
            |     |           +--:(ip-address)
            |     |           |  +--ro source-address?   inet:ip-address
            |     |           |  +--ro group-ip-address? IP-Multicast-Group-Address
            |     |           +--:(vpn)
            |     |           |  +--ro as-number?             inet:as-number
            |     |           +--:(global-id)
            |     |              +--ro lsp-id?                string
            |     +--:(tlv-address)
            |        +--ro tlv-type?              int16
            |        +--ro tlv-len?               int16
            |        +--ro tlv-value?             binary
            +--ro min-delay?         oam-counter32
            +--ro average-delay?     oam-counter32
            +--ro max-delay?         oam-counter32

data hierarchy of OAM

4. OAM YANG Module

<CODE BEGINS> file "ietf-connectionless-oam.yang"

  module ietf-connectionless-oam {
    namespace "urn:ietf:params:xml:ns:yang:ietf-connectionless-oam";
    prefix coam;

    import ietf-network{
      prefix nd;
    }
    import ietf-yang-types {
      prefix yang;
    }
    import ietf-interfaces {
      prefix if;
    }
    import ietf-inet-types {
      prefix inet;
    }
    import ietf-routing {
      prefix rt;
    }
    organization "IETF LIME Working Group";
    contact
      "Deepak Kumar dekumar@cisco.com
       Qin Wu       bill.wu@huawei.com";
    description
      "This YANG module defines the generic configuration,
       statistics and rpc for connectionless OAM to be
       used within IETF in a protocol indpendent manner.
       Functional level abstraction is indendent with
       YANG modeling. It is assumed that each protocol maps
       corresponding abstracts to its native format.
       Each protocol may extend the YANG model defined
       here to include protocol specific extensions";
    revision 2015-12-22 {
      description
        "Initial revision. - 01 version";
      reference "";
    }
    /* features */
    feature connection-less {
      description
        "this feature indicates that OAM solution is connection less.";
    }
    feature continuity-check {
      description
        "This feature indicates that the server supports
         executing continuity check OAM command and
         returning a response. Servers that do not advertise
         this feature will not support executing
         continuity check command or rpc model for
         continuity check command.";
    }
    feature path-discovery {
        description
        "This feature indicates that the server supports
         executing path discovery OAM command and
         returning a response. Servers that do not advertise
         this feature will not support executing
         path discovery command or rpc model for
         path discovery command.";
    }
    /* Identities */
    /* typedefs */
       typedef IPv4-Multicast-Group-Address {
            type string {
             pattern '(2((2[4-9])|(3[0-9]))\.)'
                         +'(([0-9]|[1-9][0-9]|1[0-9][0-9]|'
                         +'2[0-4][0-9]|25[0-5])\.){2}'
                         +'([0-9]|[1-9][0-9]|1[0-9][0-9]'
                         +'|2[0-4][0-9]|25[0-5])';
            }
            description
              "The IPv4-Multicast-Group-Address type
               represents an IPv4 multicast address
               in dotted-quad notation.";
            reference "RFC4607";
      } // typedef IPv4-Multicast-Group-Address
      typedef IPv6-Multicast-Group-Address {
            type string {
            pattern
                        '(((FF|ff)[0-9a-fA-F]{2}):)([0-9a-fA-F]'
                        +'{0,4}:){0,5}((([0-9a-fA-F]{0,4}:)?'
                        +'(:|[0-9a-fA-F]{0,4}))|(((25[0-5]|2[0-4]'
                        +'[0-9]|[01]?[0-9]?[0-9])\.){3}(25[0-5]|'
                        +'2[0-4][0-9]|[01]?[0-9]?[0-9])))';
            pattern
            '(([^:]+:){6}(([^:]+:[^:]+)|'
                        +'(.*\..*)))|((([^:]+:)*[^:]+)'
                        +'?::(([^:]+:)*[^:]+)?)';
             }
            description
                        "The IPv6-Multicast-Group-Address
                        type represents an IPv6 address in full,
                        mixed, shortened, and shortened-mixed
                        notation.";
            reference "RFC4291 2.7.
            ietf-inet-types:ipv6-address";
      }
      typedef IP-Multicast-Group-Address {
            type union {
              type IPv4-Multicast-Group-Address;
              type IPv6-Multicast-Group-Address;
            }
            description
             "The IP-Multicast-Group-Address type
              represents an IP multicast address and
              is IP version neutral. The format of the
              textual representations implies the IP version.";
      } // typedef IP-Multicast-Group-Address

    identity fec-types {
      description
      "This is base identity of fec types which are ip-prefix,
       bgp, tunnel, l3vpn, pwe3, vpls, etc.";
    }

    typedef fec-type {
      type identityref {
        base fec-types;
      }
      description "Target FEC type.";
    }

    typedef oam-counter32 {
      type yang:zero-based-counter32;
      description
        "defines 32 bit counter for OAM";
    }
    /* groupings */

    grouping cc-session-statsitics {
      description "Grouping for session statistics";
      container cc-session-statistics {
        description "cc session counters";
        leaf session-count {
           type uint32;
           description "Number of cc sessions.";
        }
        leaf session-up-count {
           type uint32;
           description "Number of sessions which are up.";
        }
        leaf session-down-count {
           type uint32;
           description "Number of sessions which are down.";
        }
        leaf session-admin-down-count {
           type uint32;
           description "Number of sessions which are admin-down.";
        }
      }
    }

    grouping cc-per-session-statistics {
      description "Grouping for per session statistics";
      container cc-per-session-statistics {
        description "per session statistics.";
        leaf create-time {
          type yang:date-and-time;
          description "Time and date when session is created.";
        }
        leaf last-down-time {
          type yang:date-and-time;
          description "Time and date last time session is down.";
        }
        leaf last-up-time {
          type yang:date-and-time;
          description "Time and date last time session is up.";
        }
        leaf down-count {
          type uint32;
          description "Total down count.";
        }
        leaf admin-down-count {
          type uint32;
          description "Total down count.";       
        }
        leaf rx-packet-count {
          type uint32;
          description "Total receive packet count.";
        }
        leaf tx-packet-count {
          type uint32;
          description "Total transmit packet count.";
        }
        leaf rx-bad-packet {
          type uint32;
          description "Total receive bad packet.";
        }
        leaf tx-packet-failed {
          type uint32;
          description "Total send packet failed.";
        }
      }
    }
    
    grouping session-type {
      description
        "This object indicates the current session
         definition.";
      leaf session-type-enum {
        type enumeration {
          enum proactive {
            description
              "The current session is proactive";
          }
          enum on-demand {
            description
              "The current session is on-demand.";
          }
        }
        default "on-demand";
        description
          "session type enum";
      }
    }
    grouping tp-address {
      choice tp-address {
        case mac-address {
          leaf mac-address {
            type yang:mac-address;
            description
            "MAC Address";
          }
          description
          "MAC Address based MP Addressing.";
        }
        case ipv4-address {
          leaf ipv4-address {
            type inet:ipv4-address;
            description
            "Ipv4 Address";
          }
          description
          "Ip Address based MP Addressing.";
        }
        case ipv6-address {
          leaf ipv6-address {
            type inet:ipv6-address;
            description
            "Ipv6 Address";
          }
          description
          "ipv6 Address based MP Addressing.";
        }
        case src-dst-address {
          leaf src-ip-address {
            type inet:ip-address;
                    description
                    "source ip address.";
          }
          leaf dst-ip-address {
            type inet:ip-address;
                    description
                    "destination ip address.";
          }
          leaf Interface {
            type if:interface-ref;
                    description
                    "interface.";
          }
        }
        case fec {
          leaf fec-type {
            type fec-type;
                    description
                    "fec type.";
          }
          choice fec-value {
                   description
                   "fec value.";
            case ip-prefix {
              leaf ip-prefix {
                type inet:ip-prefix;
                            description
                            "ip prefix.";
              }
            }
            case bgp {
              leaf bgp {
                type inet:ip-prefix;
                            description
                            "BGP Labeled Prefix ";
              }
            }
            case tunnel {
              leaf tunnel-interface {
                type uint32;
                            description
                            "VPN Prefix ";
              }
            }
            case l3vpn {
              leaf l3vpn-id {
                type uint32;
                            description
                "FEC layer 3 vpn.";
              }
            }
            case pw {
              leaf remote-pe-address{
               type inet:ip-address;
                           description
                           "remote pe address.";
              }
              leaf pw-id {
                type uint32;
                            description
                            "Pseudowire id.";
              }
            }
            case vpls {
              leaf route-distinguisher {
                type uint32;
                            description
                            "Route Distinguisher(8 octets).";
              }
              leaf sender-ve-id{
               type uint32;
                           description
                           "Sender's VE ID.";
              }
              leaf receiver-ve-id{
               type uint32;
                           description
                           "Receiver's VE ID.";
              }
            }
            case mpls-mldp{
             choice root-address{
                      description
                          "root address choice.";
              case ip-address{
               leaf source-address{
                type inet:ip-address;
                            description
                            "ip address.";
               }
               leaf group-ip-address{
                type IP-Multicast-Group-Address;
                            description
                            "group ip address.";
               }
              }
              case vpn{
               leaf as-number{
                type inet:as-number;
                            description
                            "AS number.";
               }
              }
              case global-id{
               leaf lsp-id{
                type string;
                            description
                            "lsp id.";
               }
              }
             }
            }
          }
        }
        case tlv-address {
           leaf tlv-type {
             type int16;
             description
               "Type of MEP-ID";
           }
           leaf tlv-len {
             type int16;
             description
               "Length of MEP-ID value";
           }
           leaf tlv-value {
             type binary {
               length "12..255";
           }
           description
             "Value please refer RFC6428 (Figure 4,5,6).";
           }
        description
          "MEP-ID";
      }
        description
          "TP Addressing.";
      }
      description
        "TP Address";
    }
    grouping connectionless-oam-layers {
      list oam-layers {
         key "index";
         leaf index {
             type uint16 {
                  range "0..65535";
             }
             description
               "Index";
         }
        leaf level {
            type int32 {
                 range "-1..1";
            }
            default 0;
            description
              "Level 0 indicates default level, -1 means server
               and +1 means client layer.
               In relationship 0 means same layer.";
        }
        uses tp-address;
        ordered-by user;
         description
            "list of related oam layers.
             0 means they are in same level, especially
             interworking scenarios of stiching multiple
             technology at same layer.
             -1 means server layer, for eg:- in case of
             Overlay and Underlay, Underlay is server layer for
             Overlay Test Point.
             +1 means client layer, for eg:- in case of
             Service OAM and Transport OAM, Service OAM is client
             layer to Transport OAM.";
      }
      description
        "connectionless related OAM layer";
    }
    grouping tp-technology {
       choice technology {
          default technology-null;
          case technology-null {
            description
              "this is a placeholder when no technology is needed.";
            leaf tech-null {
               type empty;
               description
                 "there is no technology define";
            }
          }
          description
            "technology choice null";
         case technology-string {
            description
            "oam technology string";
            leaf ipv4-icmp {
              type string;
              description
                "name to identify oam technology";
            }
         }
       }
       description
        "OAM Technology";
    }
    grouping tp-tools {
      description
        "Test Point OAM Toolset.";
      choice tools {
           default tools-empty;
           description
           "choice of test point tools.
            Empty tools means based on Test Point it's implicit
            all OAM tools are present and no further configuration
            is supported.";
        case tools-empty {
          description
            "this is a placeholder when oam toolset is not needed.";
          leaf tools-null {
            type empty;
            description
              "there is no oam toolset defined.";
          }
        }
        case tools-ip{
          description
            "Oam Toolset for Ip";
          leaf rfc792 {
            type boolean;
            description
              "rfc792 (icmpv4) supported.";
          }
          leaf rfc4443 {
            type boolean;
            description
              "rfc4443 supported.";
          }
          leaf rfc4884 {
            type boolean;
                    description
                    "rfc4884 supported.";
          }
          leaf rfc5837 {
            type boolean;
                    description
                    "rfc5837 supported.";
          }
        }
        case tools-bfd {
          leaf rfc5880 {
            type boolean;
                    description
                    "rfc5880 supported.";
          }
          leaf rfc5881 {
            type boolean;
                    description
                    "rfc5881 supported.";
          }
          leaf rfc5882 {
            type boolean;
                    description
                    "rfc5882 supported.";
          }
          leaf rfc5883 {
            type boolean;
                    description
                    "rfc5883 supported.";
          }
          leaf rfc5884 {
            type boolean;
                    description
                    "rfc5884 supported.";
          }
          leaf rfc5885 {
            type boolean;
                    description
                    "rfc5885 supported.";
          }
        }
        case tools-mpls {
          description
            "Oam Toolset for mpls";
          leaf rfc4379 {
            type boolean;
                    description
                    "rfc4379 supported.";
          }
          leaf rfc4687 {
            type boolean;
                    description
                    "rfc4687 supported.";
          }
          leaf rfc4950 {
            type boolean;
                    description
                    "rfc4950 supported.";
          }
          leaf mpls-rfc5884 {
            type boolean;
                    description
                    "rfc5884 supported.";
          }
        }
        case tools-mpls-tp {
          description
            "Oam Toolset for mpls TP.";
          leaf rfc6428 {
            type boolean;
                    description
                    "rfc6428 supported.";
          }
          leaf rfc6426 {
            type boolean;
                    description
                    "rfc6426 supported.";
          }
          leaf rfc6435 {
            type boolean;
                    description
                    "rfc6435 supported.";
          }
          leaf rfc6374 {
            type boolean;
                    description
                    "rfc6374 supported.";
          }
          leaf rfc6375 {
            type boolean;
                    description
                    "rfc6375 supported.";
          }
        }
        case tools-pw {
          description
            "Oam Toolset for pw oam.";
          leaf rfc5085 {
            type boolean;
                    description
                    "rfc5085 supported.";
          }
          leaf pw_rfc5885 {
            type boolean;
                    description
                    "rfc5885 supported.";
          }
          leaf rfc6423 {
            type boolean;
                    description
                    "rfc6423 supported.";
          }
          leaf rfc6310 {
            type boolean;
                    description
                    "rfc6310 supported.";
          }
          leaf rfc7023 {
            type boolean;
                    description
                    "rfc7023 supported.";
          }
        }
      }
    }
    grouping test-point-location {
      leaf vrf {
        type rt:routing-instance-ref;
            description
            "The vrf is used to describe the
             corresponding network instance";
      }
      uses tp-address;
      uses tp-technology;
      uses tp-tools;
      uses connectionless-oam-layers;
      description
         "Test point Address";
    }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-ipv4-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "ipv4-location";
        leaf ipv4-location {
            type inet:ipv4-address;
            description
              "Ipv4 Address.";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }
    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-ipv6-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "ipv6-location";
        leaf ipv6-location {
            type inet:ipv6-address;
            description
              "Ipv6 Address.";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }
    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-tunnel-address-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "tunnel-location";
        leaf tunnel-location {
           type uint32;
              description
              "VPN Prefix ";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-mac-address-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "mac-address-location";
        leaf mac-address-location {
            type yang:mac-address;
            description
            "MAC Address";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-ip-prefix-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "ip-prefix-location";
        leaf ip-prefix-location {
          type inet:ip-prefix;
               description
               "ip prefix.";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-route-dist-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "route-dist-location";
        leaf route-dist-location {
            type uint32;
               description
               "Route Distinguisher(8 octets).";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-group-ip-address-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "group-ip-address-location";
        leaf group-ip-address-location {
         type IP-Multicast-Group-Address;
                     description
                     "group ip address.";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }
    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-as-number-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "as-number-location";
        leaf as-number-location {
         type inet:as-number;
                     description
                     "AS number.";
        }
        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

    augment "/nd:networks/nd:network/nd:node"{
     description
      "Augment test points of connectionless oam.";
     container test-point-lsp-id-location-list {
        if-feature connection-less;
        list test-point-locations {
        key "lsp-id-location";
        leaf lsp-id-location{
         type string;
                     description
                     "lsp id.";
        }

        uses test-point-location;
        ordered-by user;
        description
           "list of test point locations.";
      }
          description
          "Serves as top-level container for test point location list.";
    }
   }

   container oper {
     if-feature continuity-check;
     config "false";
     description "cc operational information.";
     container cc-ipv4-sessions-statistics {
       description "cc ipv4 sessions";
       uses cc-session-statsitics; 
     }
     container cc-ipv6-sessions-statistics {
       description "cc ipv6 sessions";
       uses cc-session-statsitics;
     }
   }

    rpc continuity-check {
      if-feature continuity-check;
      description
        "Generates continuity-check as per RFC7276.";
      input {
        container destination-tp {
          uses tp-address;
                  description
                  "destination test point.";
        }
        uses session-type;
        leaf source-interface {
          type if:interface-ref;
                  description
                  "source interface.";
        }
        leaf outbound-interface {
          type if:interface-ref;

                  description
                  "outbound interface.";
        }
        leaf count {
          type uint32;
          default "5";

                  description
                  "Specifies the number of packets that will be sent.";
        }
        leaf vrf {
          type rt:routing-instance-ref;

                  description
                  "vrf instance.";
        }
        leaf ttl {
          type uint8;
          default "255";

                  description
                  "Time to live (TTL).";
        }
        leaf packet-size {
          type uint32 {
            range "64..10000";
          }
          default "64";

          description
            "Size of ping echo request packets, in octets";
        }
      }
      output {
        list error-code-list {
          key "response-index";
          leaf response-index {
            type uint32;
                    description
                    "response index.";
          }
          leaf status-code {
            type int32;
            description
              "error code is ";
          }
          leaf status-sub-code {
            type uint8;
                    description
                    "sub code.";
          }
                  description
                  "error code list.";
        }
        leaf tx-packt-count {
          type oam-counter32;

          description
            "Transmitted Packet count";
        }
        leaf rx-packet-count {
          type oam-counter32;

          description
            "Received packet count";
        }
        leaf min-delay {
          type oam-counter32;
                  units milliseconds;

          description
            "Delay is specified in milliseconds";
        }
        leaf average-delay {
          type oam-counter32;
                  units milliseconds;

          description
            "average delay in milliseconds";
        }
        leaf max-delay {
          type oam-counter32;
                  units milliseconds;

          description
            "Maximum delay in milliseconds";
        }
      }
    }
    rpc path-discovery {
      description
        "Generates path discovery as per RFC7276.";
      input {
        container destination-tp {
          uses tp-address;
                  description
                  "destination test point.";
        }
        uses session-type;
        leaf source-interface {
          type if:interface-ref;

                  description
                  "source interface.";
        }
        leaf outbound-interface {
          type if:interface-ref;

                  description
                  "outbound interface.";
        }
        leaf vrf {
          type rt:routing-instance-ref;

                  description
                  "vrf";
        }
        leaf max-ttl {
          type uint8;
          default "255";

                  description
                  "max ttl.";
        }
      }
      output {
        list response-list {
          key "response-index";
                  description
                  "path discovery response list.";
          leaf response-index {
            type uint32;
                    description
                    "response index.";
          }
          leaf status-code {
            type int32;
            description
              "error code is ";
          }
          leaf status-sub-code {
            type uint8;

                    description
                    "sub code is ";
          }
          leaf hop-cnt {
            type uint8;
            description
            "hop count.";
          }
          container destination-tp {
            uses tp-address;
                    description
                    "destination test point.";
          }
          leaf min-delay {
            type oam-counter32;
            units milliseconds;

            description
              "Delay is specified in milliseconds";
          }
          leaf average-delay {
            type oam-counter32;
            units millisecond;

            description
              "average delay in milliseconds";
          }
          leaf max-delay {
            type oam-counter32;
            units millisecond;

            description
              "Maximum delay in milliseconds";
          }
        }
       }
    }
}

YANG module of OAM

<CODE ENDS>

5. Security Considerations

TBD.

6. IANA Considerations

This document registers a URI in the IETF XML registry [RFC3688] [RFC3688]. Following the format in RFC 3688, the following registration is requested to be made:

URI: urn:ietf:params:xml:ns:yang:ietf-connectionless-oam

Registrant Contact: The IESG.

XML: N/A, the requested URI is an XML namespace.

This document registers a YANG module in the YANG Module Names registry [RFC6020].

name: ietf-connectionless-oam namespace: urn:ietf:params:xml:ns:yang:ietf-connectionless-oam
   prefix: goam reference: RFC XXXX

7. 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.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011.
[RFC792] Postel, J., "Internet Control Message Protocol", RFC 792, September 1981.

Authors' Addresses

Deepak Kumar CISCO Systems 510 McCarthy Blvd Milpitas, CA 95035 USA EMail: dekumar@cisco.com
Michael Wang Huawei Technologies,Co.,Ltd 101 Software Avenue, Yuhua District Nanjing, 210012 China EMail: wangzitao@huawei.com
Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China EMail: bill.wu@huawei.com
Reshad Rahman CISCO Systems 2000 Innovation Drive KANATA, ONTARIO K2K 3E8 CANADA EMail: rrahman@cisco.com