Deterministic Networking (DetNet) Configuration YANG Model
draft-ietf-detnet-yang-05

Abstract

This document contains the specification for Deterministic Networking flow configuration YANG Model. The model allows for provisioning of end-to-end DetNet service along the path without dependency on any signaling protocol.

The YANG module defined in this document conforms to the Network Management Datastore Architecture (NMDA).

Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.

Status of This Memo

This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.

Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress."

This Internet-Draft will expire on September 10, 2020.

Copyright Notice

Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

Table of Contents

• 1. Introduction
• 2. Terminologies
• 3. DetNet Configuration Module
• 3.1. DetNet Appliction Flow Configuration Attributes
• 3.2. DetNet Service Sub-layer Configuration Attributes
• 3.3. DetNet Forwarding Sub-layer Configuration Attributes
• 4. DetNet YANG Structure Considerations
• 5. DetNet Configuration YANG Structures
• 6. DetNet Configuration YANG Model
• 7. Open Issues
• 8. IANA Considerations
• 9. Security Considerations
• 10. Acknowledgements
• 11. References
• 11.1. Normative References
• 11.2. Informative References
• Authors' Addresses

1. Introduction

DetNet (Deterministic Networking) provides a capability to carry specified unicast or multicast data flows for real-time applications with extremely low packet loss rates and assured maximum end-to-end delivery latency. A description of the general background and concepts of DetNet can be found in [RFC8655].

This document defines a YANG model for DetNet based on YANG data types and modeling language defined in [RFC6991] and [RFC7950]. DetNet service, which is designed for describing the characteristics of services being provided for application flows over a network, and DetNet configuration, which is designed for DetNet flow path establishment, flow status reporting, and DetNet functions configuration in order to achieve end-to-end bounded latency and zero congestion loss, are both included in this document.

2. Terminologies

This documents uses the terminologies defined in [RFC8655].

3. DetNet Configuration Module

DetNet configuration module includes DetNet App-flow configuration, DetNet Service Sub-layer configuration, and DetNet Forwarding Sub-layer configuration. The corresponding attributes used in different sub-layers are defined in Section 3.1, 3.2, 3.3 respectively.

3.1. DetNet Appliction Flow Configuration Attributes

DetNet application flow is responsible for mapping between application flows and DetNet flows at the edge node(egress/ingress node). Where the application flows can be either layer 2 or layer 3 flows. To map a flow at the User Network Interface (UNI), the corresponding attributes are defined in [I-D.ietf-detnet-flow-information-model].

3.2. DetNet Service Sub-layer Configuration Attributes

DetNet service functions, e.g., DetNet tunnel initialization/termination and service protection, are provided in DetNet service sub-layer. To support these functions, the following service attributes need to be configured:

• DetNet flow identification
• Service function indication, indicates which service function will be invoked at a DetNet edge, relay node or end station. (DetNet tunnel initialization or termination are default functions in DetNet service layer, so there is no need for explicit indication). The corresponding arguments for service functions also needs to be defined.

3.3. DetNet Forwarding Sub-layer Configuration Attributes

As defined in [RFC8655], DetNet forwarding sub-layer optionally provides congestion protection for DetNet flows over paths provided by the underlying network. Explicit route is another mechanism that is used by DetNet to avoid temporary interruptions caused by the convergence of routing or bridging protocols, and it is also implemented at the DetNet forwarding sub-layer.

To support congestion protection and explicit route, the following transport layer related attributes are necessary:

• Traffic Specification, refers to Section 7.2 of [I-D.ietf-detnet-flow-information-model]. It may used for resource reservation, flow shaping, filtering and policing.
• Explicit path, existing explicit route mechanisms can be reused. For example, if Segment Routing (SR) tunnel is used as the transport tunnel, the configuration is mainly at the ingress node of the transport layer; if the static MPLS tunnel is used as the transport tunnel, the configurations need to be at every transit node along the path; for pure IP based transport tunnel, it's similar to the static MPLS case.

4. DetNet YANG Structure Considerations

The picture shows that the general structure of the DetNet YANG Model:

                  +-----------+
                  |ietf-detnet|
                  +-----+-----+
                        |
          +-------------+---------------+
          |             |               |   
    +-----+-----+ +-----+-----+ +-------+------+ 
    | App Flows | |service s-l| |forwarding s-l| 
    +-----------+ +-----------+ +--------------+ 

There are three instances in DetNet YANG Model: App-flow instance, service sub-layer instance and forwarding sub-layer instance, respectively corresponding to four parts of DetNet functions defined in section 3. In each instance, there are four elements: name, in-segments, out-segments and operations, which means:

• Name: indicates the key value of the instance identification.
• In-segments: indicates the key value of identification, e.g., Layer 2 App flow identification, Layer 3 App flow identification and DetNet flow identification.
• Out-segments: indicates the information of DetNet processing(e.g., DetNet forwarding, DetNet header Encapsulation) and the mapping relationship to the lower sub-layer/sub-network.
• Operations: indicates DetNet functions, e.g., DetNet forwarding functions, DetNet Service functions, DetNet Resource Reservation.

These elements are different when the technologies used for the specific instance is different. So this structure is abstract, which allows for different technology specifics as defined in different data plane drafts.

5. DetNet Configuration YANG Structures

module: ietf-detnet-config
  +--rw app-flows
  |  +--rw app-flow* [name]
  |     +--rw name                      string
  |     +--rw end-points
  |     |  +--rw source-endpoint?       inet:ip-address
  |     |  +--rw destination-endpoints* inet:ip-address
  |     +--rw app-flow-bidir-congruent? boolean
  |     +--rw traffic-requirements
  |     |  +--rw min-bandwidth?                  uint64
  |     |  +--rw max-latency?                    uint32
  |     |  +--rw max-latency-variation?          uint32
  |     |  +--rw max-loss?                       uint8
  |     |  +--rw max-consecutive-loss-tolerance? uint32
  |     |  +--rw max-misordering?                uint32
  |     +--rw traffic-specification
  |     |  +--rw interval?                     uint32
  |     |  +--rw max-packets-per-interval?     uint32
  |     |  +--rw max-payload-size?             uint32
  |     |  +--rw average-packets-per-interval? uint32
  |     |  +--rw average-payload-size?         uint32
  |     +--rw in-segment
  |     |  +--rw app-traffic* [interface]
  |     |     +--rw interface                if:interface-ref
  |     |     +--rw (data-flow-type)?
  |     |        +--:(tsn-app-flow)
  |     |        |  +--rw source-mac-address?      yang:mac-address
  |     |        |  +--rw destination-mac-address? yang:mac-address
  |     |        |  +--rw ethertype?               eth:ethertype
  |     |        |  +--rw vlan-id?                 uint16
  |     |        |  +--rw pcp?                     uint8
  |     |        +--:(ip-app-flow)
  |     |        |  +--rw src-ip-prefix?           inet:ip-prefix
  |     |        |  +--rw dest-ip-prefix?          inet:ip-prefix
  |     |        |  +--rw next-header?             uint8
  |     |        |  +--rw traffic-class?           uint8
  |     |        |  +--rw flow-label?              inet:ipv6-flow-label
  |     |        |  +--rw source-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw destination-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw ipsec-spi?               ipsec-spi
  |     |        +--:(mpls-app-flow)
  |     |           +--rw (label-space)?
  |     |              +--:(non-platrom-label-space)
  |     |              |  +--rw mpls-label-stack
  |     |              |     +--rw entry* [id]
  |     |              |        +--rw id             uint8
  |     |              |        +--rw label?         rt-types:mpls-label
  |     |              |        +--rw ttl?           uint8
  |     |              |        +--rw traffic-class? uint8
  |     |              +--:(platform-label-space)
  |     |                 +--rw label?                   rt-types:mpls-label
  |     +--rw out-segment
  |        +--rw (next-hop-options)
  |           +--:(simple-next-hop)
  |           |  +--rw (header-type)?
  |           |  |  +--:(detnet-mpls-header)
  |           |  |  |  +--rw mpls-label-stack
  |           |  |  |     +--rw entry* [id]
  |           |  |  |        +--rw id             uint8
  |           |  |  |        +--rw label?         rt-types:mpls-label
  |           |  |  |        +--rw ttl?           uint8
  |           |  |  |        +--rw traffic-class? uint8
  |           |  |  +--:(detnet-ip-header)
  |           |  |     +--rw src-ip-address?   inet:ip-address
  |           |  |     +--rw dest-ip-address?  inet:ip-address
  |           |  |     +--rw next-header?      uint8
  |           |  |     +--rw traffic-class?    uint8
  |           |  |     +--rw flow-label?       inet:ipv6-flow-label
  |           |  |     +--rw source-port?      inet:port-number
  |           |  |     +--rw destination-port? inet:port-number
  |           |  +--rw lower-layer* [index]
  |           |     +--rw index                 uint8
  |           |     +--rw (lower-layer-type)?
  |           |        +--:(service-sub-layer)
  |           |        |  +--rw service-sub-layer?    service-sub-layer-ref
  |           |        +--:(forwarding-sub-layer)
  |           |        |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |           |        +--:(sub-network)
  |           |        |  +--rw sub-network?          sub-network-ref
  |           |        +--:(interface)
  |           |           +--rw outgoing-interface?   if:interface-ref
  |           +--:(next-hop-list)
  |              +--rw next-hop-list
  |                 +--rw next-hop* [hop-index]
  |                    +--rw hop-index         uint8
  |                    +--rw (header-type)?
  |                    |  +--:(detnet-mpls-header)
  |                    |  |  +--rw mpls-label-stack
  |                    |  |     +--rw entry* [id]
  |                    |  |        +--rw id             uint8
  |                    |  |        +--rw label?         rt-types:mpls-label
  |                    |  |        +--rw ttl?           uint8
  |                    |  |        +--rw traffic-class? uint8
  |                    |  +--:(detnet-ip-header)
  |                    |     +--rw src-ip-address?   inet:ip-address
  |                    |     +--rw dest-ip-address?  inet:ip-address
  |                    |     +--rw next-header?      uint8
  |                    |     +--rw traffic-class?    uint8
  |                    |     +--rw flow-label?       inet:ipv6-flow-label
  |                    |     +--rw source-port?      inet:port-number
  |                    |     +--rw destination-port? inet:port-number
  |                    +--rw lower-layer* [index]
  |                       +--rw index                 uint8
  |                       +--rw (lower-layer-type)?
  |                          +--:(service-sub-layer)
  |                          |  +--rw service-sub-layer?    service-sub-layer-ref
  |                          +--:(forwarding-sub-layer)
  |                          |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |                          +--:(sub-network)
  |                          |  +--rw sub-network?          sub-network-ref
  |                          +--:(interface)
  |                             +--rw outgoing-interface?   if:interface-ref
  +--rw service-sub-layer
  |  +--rw service-sub-layer-list* [name]
  |     +--rw name                    string
  |     +--ro service-id?             uint16
  |     +--rw service-rank?           uint8
  |     +--rw traffic-requirements
  |     |  +--rw min-bandwidth?                  uint64
  |     |  +--rw max-latency?                    uint32
  |     |  +--rw max-latency-variation?          uint32
  |     |  +--rw max-loss?                       uint8
  |     |  +--rw max-consecutive-loss-tolerance? uint32
  |     |  +--rw max-misordering?                uint32
  |     +--rw service-portection
  |     |  +--rw service-protection-type?     service-protection-type
  |     |  +--rw sequence-number-length?      sequence-number-field
  |     |  +--rw sequence-number-window-size? uint32
  |     |  +--rw sequence-number-generation?  sequence-number-generation-type
  |     +--rw service-operation-type? service-operation-type
  |     +--rw in-segment
  |     |  +--rw app-flow*             app-flow-ref
  |     |  +--rw incoming-detnet-flow* [incoming-index]
  |     |     +--rw incoming-index    uint8
  |     |     +--rw (detnet-flow-type)?
  |     |        +--:(ip-detnet-flow)
  |     |        |  +--rw src-ip-prefix?    inet:ip-prefix
  |     |        |  +--rw dest-ip-prefix?   inet:ip-prefix
  |     |        |  +--rw next-header?      uint8
  |     |        |  +--rw traffic-class?    uint8
  |     |        |  +--rw flow-label?       inet:ipv6-flow-label
  |     |        |  +--rw source-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw destination-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw ipsec-spi?        ipsec-spi
  |     |        +--:(mpls-detnet-flow)
  |     |           +--rw (label-space)?
  |     |              +--:(non-platrom-label-space)
  |     |              |  +--rw mpls-label-stack
  |     |              |     +--rw entry* [id]
  |     |              |        +--rw id             uint8
  |     |              |        +--rw label?         rt-types:mpls-label
  |     |              |        +--rw ttl?           uint8
  |     |              |        +--rw traffic-class? uint8
  |     |              +--:(platform-label-space)
  |     |                 +--rw label?            rt-types:mpls-label
  |     +--rw out-sergment
  |        +--rw (next-hop-options)
  |        |  +--:(simple-next-hop)
  |        |  |  +--rw (header-type)?
  |        |  |  |  +--:(detnet-mpls-header)
  |        |  |  |  |  +--rw mpls-label-stack
  |        |  |  |  |     +--rw entry* [id]
  |        |  |  |  |        +--rw id             uint8
  |        |  |  |  |        +--rw label?         rt-types:mpls-label
  |        |  |  |  |        +--rw ttl?           uint8
  |        |  |  |  |        +--rw traffic-class? uint8
  |        |  |  |  +--:(detnet-ip-header)
  |        |  |  |     +--rw src-ip-address?   inet:ip-address
  |        |  |  |     +--rw dest-ip-address?  inet:ip-address
  |        |  |  |     +--rw next-header?      uint8
  |        |  |  |     +--rw traffic-class?    uint8
  |        |  |  |     +--rw flow-label?       inet:ipv6-flow-label
  |        |  |  |     +--rw source-port?      inet:port-number
  |        |  |  |     +--rw destination-port? inet:port-number
  |        |  |  +--rw lower-layer* [index]
  |        |  |     +--rw index                 uint8
  |        |  |     +--rw (lower-layer-type)?
  |        |  |        +--:(service-sub-layer)
  |        |  |        |  +--rw service-sub-layer?    service-sub-layer-ref
  |        |  |        +--:(forwarding-sub-layer)
  |        |  |        |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |        |  |        +--:(sub-network)
  |        |  |        |  +--rw sub-network?          sub-network-ref
  |        |  |        +--:(interface)
  |        |  |           +--rw outgoing-interface?   if:interface-ref
  |        |  +--:(next-hop-list)
  |        |     +--rw next-hop-list
  |        |        +--rw next-hop* [hop-index]
  |        |           +--rw hop-index         uint8
  |        |           +--rw (header-type)?
  |        |           |  +--:(detnet-mpls-header)
  |        |           |  |  +--rw mpls-label-stack
  |        |           |  |     +--rw entry* [id]
  |        |           |  |        +--rw id             uint8
  |        |           |  |        +--rw label?         rt-types:mpls-label
  |        |           |  |        +--rw ttl?           uint8
  |        |           |  |        +--rw traffic-class? uint8
  |        |           |  +--:(detnet-ip-header)
  |        |           |     +--rw src-ip-address?   inet:ip-address
  |        |           |     +--rw dest-ip-address?  inet:ip-address
  |        |           |     +--rw next-header?      uint8
  |        |           |     +--rw traffic-class?    uint8
  |        |           |     +--rw flow-label?       inet:ipv6-flow-label
  |        |           |     +--rw source-port?      inet:port-number
  |        |           |     +--rw destination-port? inet:port-number
  |        |           +--rw lower-layer* [index]
  |        |              +--rw index                 uint8
  |        |              +--rw (lower-layer-type)?
  |        |                 +--:(service-sub-layer)
  |        |                 |  +--rw service-sub-layer?    service-sub-layer-ref
  |        |                 +--:(forwarding-sub-layer)
  |        |                 |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |        |                 +--:(sub-network)
  |        |                 |  +--rw sub-network?          sub-network-ref
  |        |                 +--:(interface)
  |        |                    +--rw outgoing-interface?   if:interface-ref
  |        +--rw app-flow*         app-flow-ref
  +--rw forwarding-sub-layer
  |  +--rw forwarding-sub-layer-list* [name]
  |     +--rw name                       string
  |     +--rw resource-allocation
  |     |  +--rw traffic-specification
  |     |     +--rw interval?                     uint32
  |     |     +--rw max-packets-per-interval?     uint32
  |     |     +--rw max-payload-size?             uint32
  |     |     +--rw average-packets-per-interval? uint32
  |     |     +--rw average-payload-size?         uint32
  |     +--rw forwarding-operation-type? mpls-operations-type
  |     +--rw in-segment
  |     |  +--rw service-sub-layer?  service-sub-layer-ref
  |     |  +--rw forwarding-traffic* [interface]
  |     |     +--rw interface         if:interface-ref
  |     |     +--rw (detnet-flow-type)?
  |     |        +--:(ip-detnet-flow)
  |     |        |  +--rw src-ip-prefix?    inet:ip-prefix
  |     |        |  +--rw dest-ip-prefix?   inet:ip-prefix
  |     |        |  +--rw next-header?      uint8
  |     |        |  +--rw traffic-class?    uint8
  |     |        |  +--rw flow-label?       inet:ipv6-flow-label
  |     |        |  +--rw source-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw destination-port
  |     |        |  |  +--rw (port-range-or-operator)?
  |     |        |  |     +--:(range)
  |     |        |  |     |  +--rw lower-port  inet:port-number
  |     |        |  |     |  +--rw upper-port  inet:port-number
  |     |        |  |     +--:(operator)
  |     |        |  |        +--rw operator?   operator
  |     |        |  |        +--rw port        inet:port-number
  |     |        |  +--rw ipsec-spi?        ipsec-spi
  |     |        +--:(mpls-detnet-flow)
  |     |           +--rw (label-space)?
  |     |              +--:(non-platrom-label-space)
  |     |              |  +--rw mpls-label-stack
  |     |              |     +--rw entry* [id]
  |     |              |        +--rw id             uint8
  |     |              |        +--rw label?         rt-types:mpls-label
  |     |              |        +--rw ttl?           uint8
  |     |              |        +--rw traffic-class? uint8
  |     |              +--:(platform-label-space)
  |     |                 +--rw label?            rt-types:mpls-label
  |     +--rw out-segment
  |        +--rw (next-hop-options)
  |        |  +--:(simple-next-hop)
  |        |  |  +--rw (header-type)?
  |        |  |  |  +--:(detnet-mpls-header)
  |        |  |  |  |  +--rw mpls-label-stack
  |        |  |  |  |     +--rw entry* [id]
  |        |  |  |  |        +--rw id             uint8
  |        |  |  |  |        +--rw label?         rt-types:mpls-label
  |        |  |  |  |        +--rw ttl?           uint8
  |        |  |  |  |        +--rw traffic-class? uint8
  |        |  |  |  +--:(detnet-ip-header)
  |        |  |  |     +--rw src-ip-address?    inet:ip-address
  |        |  |  |     +--rw dest-ip-address?   inet:ip-address
  |        |  |  |     +--rw next-header?       uint8
  |        |  |  |     +--rw traffic-class?     uint8
  |        |  |  |     +--rw flow-label?        inet:ipv6-flow-label
  |        |  |  |     +--rw source-port?       inet:port-number
  |        |  |  |     +--rw destination-port?  inet:port-number
  |        |  |  +--rw lower-layer* [index]
  |        |  |     +--rw index                 uint8
  |        |  |     +--rw (lower-layer-type)?
  |        |  |        +--:(service-sub-layer)
  |        |  |        |  +--rw service-sub-layer?    service-sub-layer-ref
  |        |  |        +--:(forwarding-sub-layer)
  |        |  |        |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |        |  |        +--:(sub-network)
  |        |  |        |  +--rw sub-network?          sub-network-ref
  |        |  |        +--:(interface)
  |        |  |           +--rw outgoing-interface?   if:interface-ref
  |        |  +--:(next-hop-list)
  |        |     +--rw next-hop-list
  |        |        +--rw next-hop* [hop-index]
  |        |           +--rw hop-index         uint8
  |        |           +--rw (header-type)?
  |        |           |  +--:(detnet-mpls-header)
  |        |           |  |  +--rw mpls-label-stack
  |        |           |  |     +--rw entry* [id]
  |        |           |  |        +--rw id             uint8
  |        |           |  |        +--rw label?         rt-types:mpls-label
  |        |           |  |        +--rw ttl?           uint8
  |        |           |  |        +--rw traffic-class? uint8
  |        |           |  +--:(detnet-ip-header)
  |        |           |     +--rw src-ip-address?   inet:ip-address
  |        |           |     +--rw dest-ip-address?  inet:ip-address
  |        |           |     +--rw next-header?      uint8
  |        |           |     +--rw traffic-class?    uint8
  |        |           |     +--rw flow-label?       inet:ipv6-flow-label
  |        |           |     +--rw source-port?      inet:port-number
  |        |           |     +--rw destination-port? inet:port-number
  |        |           +--rw lower-layer* [index]
  |        |              +--rw index                 uint8
  |        |              +--rw (lower-layer-type)?
  |        |                 +--:(service-sub-layer)
  |        |                 |  +--rw service-sub-layer?    service-sub-layer-ref
  |        |                 +--:(forwarding-sub-layer)
  |        |                 |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
  |        |                 +--:(sub-network)
  |        |                 |  +--rw sub-network?          sub-network-ref
  |        |                 +--:(interface)
  |        |                    +--rw outgoing-interface?   if:interface-ref
  |        +--rw service-sub-layer? service-sub-layer-ref
  +--rw sub-network
     +--rw sub-network-list* [name]
        +--rw name  string

  grouping ip-header:
    +--rw src-ip-address?   inet:ip-address
    +--rw dest-ip-address?  inet:ip-address
    +--rw next-header?      uint8
    +--rw traffic-class?    uint8
    +--rw flow-label?       inet:ipv6-flow-label
    +--rw source-port?      inet:port-number
    +--rw destination-port? inet:port-number
  grouping l2-header:
    +--rw source-mac-address?      yang:mac-address
    +--rw destination-mac-address? yang:mac-address
    +--rw ethertype?               eth:ethertype
    +--rw vlan-id?                 uint16
    +--rw pcp?                     uint8
  grouping destination-ip-port-identification:
    +--rw destination-port
       +--rw (port-range-or-operator)?
          +--:(range)
          |  +--rw lower-port  inet:port-number
          |  +--rw upper-port  inet:port-number
          +--:(operator)
             +--rw operator?   operator
             +--rw port        inet:port-number
  grouping source-ip-port-identification:
    +--rw source-port
       +--rw (port-range-or-operator)?
          +--:(range)
          |  +--rw lower-port  inet:port-number
          |  +--rw upper-port  inet:port-number
          +--:(operator)
             +--rw operator?   operator
             +--rw port        inet:port-number
  grouping ip-flow-identification:
    +--rw src-ip-prefix?    inet:ip-prefix
    +--rw dest-ip-prefix?   inet:ip-prefix
    +--rw next-header?      uint8
    +--rw traffic-class?    uint8
    +--rw flow-label?       inet:ipv6-flow-label
    +--rw source-port
    |  +--rw (port-range-or-operator)?
    |     +--:(range)
    |     |  +--rw lower-port  inet:port-number
    |     |  +--rw upper-port  inet:port-number
    |     +--:(operator)
    |        +--rw operator?   operator
    |        +--rw port        inet:port-number
    +--rw destination-port
    |  +--rw (port-range-or-operator)?
    |     +--:(range)
    |     |  +--rw lower-port  inet:port-number
    |     |  +--rw upper-port  inet:port-number
    |     +--:(operator)
    |        +--rw operator?   operator
    |        +--rw port        inet:port-number
    +--rw ipsec-spi?        ipsec-spi
  grouping mpls-flow-identification:
    +--rw (label-space)?
       +--:(non-platrom-label-space)
       |  +--rw mpls-label-stack
       |     +--rw entry* [id]
       |        +--rw id             uint8
       |        +--rw label?         rt-types:mpls-label
       |        +--rw ttl?           uint8
       |        +--rw traffic-class? uint8
       +--:(platform-label-space)
          +--rw label?            rt-types:mpls-label
  grouping traffic-specification:
    +--rw traffic-specification
       +--rw interval?                     uint32
       +--rw max-packets-per-interval?     uint32
       +--rw max-payload-size?             uint32
       +--rw average-packets-per-interval? uint32
       +--rw average-payload-size?         uint32
  grouping traffic-requirements:
    +--rw traffic-requirements
       +--rw min-bandwidth?                  uint64
       +--rw max-latency?                    uint32
       +--rw max-latency-variation?          uint32
       +--rw max-loss?                       uint8
       +--rw max-consecutive-loss-tolerance? uint32
       +--rw max-misordering?                uint32
  grouping data-flow-spec:
    +--rw (data-flow-type)?
       +--:(tsn-app-flow)
       |  +--rw source-mac-address?      yang:mac-address
       |  +--rw destination-mac-address? yang:mac-address
       |  +--rw ethertype?               eth:ethertype
       |  +--rw vlan-id?                 uint16
       |  +--rw pcp?                     uint8
       +--:(ip-app-flow)
       |  +--rw src-ip-prefix?           inet:ip-prefix
       |  +--rw dest-ip-prefix?          inet:ip-prefix
       |  +--rw next-header?             uint8
       |  +--rw traffic-class?           uint8
       |  +--rw flow-label?              inet:ipv6-flow-label
       |  +--rw source-port
       |  |  +--rw (port-range-or-operator)?
       |  |     +--:(range)
       |  |     |  +--rw lower-port  inet:port-number
       |  |     |  +--rw upper-port  inet:port-number
       |  |     +--:(operator)
       |  |        +--rw operator?   operator
       |  |        +--rw port        inet:port-number
       |  +--rw destination-port
       |  |  +--rw (port-range-or-operator)?
       |  |     +--:(range)
       |  |     |  +--rw lower-port  inet:port-number
       |  |     |  +--rw upper-port  inet:port-number
       |  |     +--:(operator)
       |  |        +--rw operator?   operator
       |  |        +--rw port        inet:port-number
       |  +--rw ipsec-spi?               ipsec-spi
       +--:(mpls-app-flow)
          +--rw (label-space)?
             +--:(non-platrom-label-space)
             |  +--rw mpls-label-stack
             |     +--rw entry* [id]
             |        +--rw id             uint8
             |        +--rw label?         rt-types:mpls-label
             |        +--rw ttl?           uint8
             |        +--rw traffic-class? uint8
             +--:(platform-label-space)
                +--rw label?                   rt-types:mpls-label
  grouping detnet-flow-spec:
    +--rw (detnet-flow-type)?
       +--:(ip-detnet-flow)
       |  +--rw src-ip-prefix?    inet:ip-prefix
       |  +--rw dest-ip-prefix?   inet:ip-prefix
       |  +--rw next-header?      uint8
       |  +--rw traffic-class?    uint8
       |  +--rw flow-label?       inet:ipv6-flow-label
       |  +--rw source-port
       |  |  +--rw (port-range-or-operator)?
       |  |     +--:(range)
       |  |     |  +--rw lower-port  inet:port-number
       |  |     |  +--rw upper-port  inet:port-number
       |  |     +--:(operator)
       |  |        +--rw operator?   operator
       |  |        +--rw port        inet:port-number
       |  +--rw destination-port
       |  |  +--rw (port-range-or-operator)?
       |  |     +--:(range)
       |  |     |  +--rw lower-port  inet:port-number
       |  |     |  +--rw upper-port  inet:port-number
       |  |     +--:(operator)
       |  |        +--rw operator?   operator
       |  |        +--rw port        inet:port-number
       |  +--rw ipsec-spi?        ipsec-spi
       +--:(mpls-detnet-flow)
          +--rw (label-space)?
             +--:(non-platrom-label-space)
             |  +--rw mpls-label-stack
             |     +--rw entry* [id]
             |        +--rw id             uint8
             |        +--rw label?         rt-types:mpls-label
             |        +--rw ttl?           uint8
             |        +--rw traffic-class? uint8
             +--:(platform-label-space)
                +--rw label?            rt-types:mpls-label
  grouping app-flows-ref:
    +--rw app-flow* app-flow-ref
  grouping incoming-detnet-flows:
    +--rw incoming-detnet-flow* [incoming-index]
       +--rw incoming-index    uint8
       +--rw (detnet-flow-type)?
          +--:(ip-detnet-flow)
          |  +--rw src-ip-prefix?    inet:ip-prefix
          |  +--rw dest-ip-prefix?   inet:ip-prefix
          |  +--rw next-header?      uint8
          |  +--rw traffic-class?    uint8
          |  +--rw flow-label?       inet:ipv6-flow-label
          |  +--rw source-port
          |  |  +--rw (port-range-or-operator)?
          |  |     +--:(range)
          |  |     |  +--rw lower-port  inet:port-number
          |  |     |  +--rw upper-port  inet:port-number
          |  |     +--:(operator)
          |  |        +--rw operator?   operator
          |  |        +--rw port        inet:port-number
          |  +--rw destination-port
          |  |  +--rw (port-range-or-operator)?
          |  |     +--:(range)
          |  |     |  +--rw lower-port  inet:port-number
          |  |     |  +--rw upper-port  inet:port-number
          |  |     +--:(operator)
          |  |        +--rw operator?   operator
          |  |        +--rw port        inet:port-number
          |  +--rw ipsec-spi?        ipsec-spi
          +--:(mpls-detnet-flow)
             +--rw (label-space)?
                +--:(non-platrom-label-space)
                |  +--rw mpls-label-stack
                |     +--rw entry* [id]
                |        +--rw id             uint8
                |        +--rw label?         rt-types:mpls-label
                |        +--rw ttl?           uint8
                |        +--rw traffic-class? uint8
                +--:(platform-label-space)
                   +--rw label?            rt-types:mpls-label
  grouping detnet-header:
    +--rw (header-type)?
       +--:(detnet-mpls-header)
       |  +--rw mpls-label-stack
       |     +--rw entry* [id]
       |        +--rw id             uint8
       |        +--rw label?         rt-types:mpls-label
       |        +--rw ttl?           uint8
       |        +--rw traffic-class? uint8
       +--:(detnet-ip-header)
          +--rw src-ip-address?   inet:ip-address
          +--rw dest-ip-address?  inet:ip-address
          +--rw next-header?      uint8
          +--rw traffic-class?    uint8
          +--rw flow-label?       inet:ipv6-flow-label
          +--rw source-port?      inet:port-number
          +--rw destination-port? inet:port-number
  grouping lower-layer-ref:
    +--rw (lower-layer-type)?
       +--:(service-sub-layer)
       |  +--rw service-sub-layer?    service-sub-layer-ref
       +--:(forwarding-sub-layer)
       |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
       +--:(sub-network)
       |  +--rw sub-network?          sub-network-ref
       +--:(interface)
          +--rw outgoing-interface?   if:interface-ref
  grouping detnet-next-hop-content:
    +--rw (next-hop-options)
       +--:(simple-next-hop)
       |  +--rw (header-type)?
       |  |  +--:(detnet-mpls-header)
       |  |  |  +--rw mpls-label-stack
       |  |  |     +--rw entry* [id]
       |  |  |        +--rw id             uint8
       |  |  |        +--rw label?         rt-types:mpls-label
       |  |  |        +--rw ttl?           uint8
       |  |  |        +--rw traffic-class? uint8
       |  |  +--:(detnet-ip-header)
       |  |     +--rw src-ip-address?   inet:ip-address
       |  |     +--rw dest-ip-address?  inet:ip-address
       |  |     +--rw next-header?      uint8
       |  |     +--rw traffic-class?    uint8
       |  |     +--rw flow-label?       inet:ipv6-flow-label
       |  |     +--rw source-port?      inet:port-number
       |  |     +--rw destination-port? inet:port-number
       |  +--rw lower-layer* [index]
       |     +--rw index                 uint8
       |     +--rw (lower-layer-type)?
       |        +--:(service-sub-layer)
       |        |  +--rw service-sub-layer?    service-sub-layer-ref
       |        +--:(forwarding-sub-layer)
       |        |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
       |        +--:(sub-network)
       |        |  +--rw sub-network?          sub-network-ref
       |        +--:(interface)
       |           +--rw outgoing-interface?   if:interface-ref
       +--:(next-hop-list)
          +--rw next-hop-list
             +--rw next-hop* [hop-index]
                +--rw hop-index         uint8
                +--rw (header-type)?
                |  +--:(detnet-mpls-header)
                |  |  +--rw mpls-label-stack
                |  |     +--rw entry* [id]
                |  |        +--rw id             uint8
                |  |        +--rw label?         rt-types:mpls-label
                |  |        +--rw ttl?           uint8
                |  |        +--rw traffic-class? uint8
                |  +--:(detnet-ip-header)
                |     +--rw src-ip-address?   inet:ip-address
                |     +--rw dest-ip-address?  inet:ip-address
                |     +--rw next-header?      uint8
                |     +--rw traffic-class?    uint8
                |     +--rw flow-label?       inet:ipv6-flow-label
                |     +--rw source-port?      inet:port-number
                |     +--rw destination-port? inet:port-number
                +--rw lower-layer* [index]
                   +--rw index                 uint8
                   +--rw (lower-layer-type)?
                      +--:(service-sub-layer)
                      |  +--rw service-sub-layer?    service-sub-layer-ref
                      +--:(forwarding-sub-layer)
                      |  +--rw forwarding-sub-layer? forwarding-sub-layer-ref
                      +--:(sub-network)
                      |  +--rw sub-network?          sub-network-ref
                      +--:(interface)
                         +--rw outgoing-interface?   if:interface-ref

6. DetNet Configuration YANG Model

module ietf-detnet-config {
  namespace "urn:ietf:params:xml:ns:yang:ietf-detnet-config";
  prefix "ietf-detnet";

  import ietf-yang-types {
    prefix "yang";
  }

  import ietf-inet-types{
    prefix "inet";
  }

  import ietf-ethertypes {
    prefix "eth";
  }

  import ietf-routing-types {
    prefix "rt-types";
  }

  import ietf-routing {
    prefix "rt";
  }

  import ietf-packet-fields {
    prefix "packet-fields";
  }
  import ietf-interfaces {
    prefix "if";
  }
  

  organization "IETF DetNet Working Group";

  contact
    "WG Web:   <http://tools.ietf.org/wg/detnet/>
     WG List:  <mailto: detnet@ietf.org>
     WG Chair: Lou Berger
                 <mailto:lberger@labn.net>

                 Janos Farkas
                 <mailto:janos.farkas@ericsson.com>

     Editor:   Xuesong Geng
                <mailto:gengxuesong@huawei.com>

     Editor:   Mach Chen
                <mailto:mach.chen@huawei.com>

     Editor:   Zhenqiang Li
                <mailto:lizhenqiang@chinamobile.com>

     Editor:   Reshad Rahman
                <mailto:rrahman@cisco.com>

     Editor:   Yeoncheol Ryoo
                <mailto:dbduscjf@etri.re.kr>";

  description
    "This YANG module describes the parameters needed
     for DetNet flow configuration and flow status
  reporting";

  revision 2020-03-04 {
    description "initial revision";
    reference "RFC XXXX: draft-ietf-detnet-yang-02";
  }

  typedef app-flow-ref {
    type leafref {
      path "/ietf-detnet:app-flows"
         + "/ietf-detnet:app-flow"
         + "/ietf-detnet:name";
    }
  }
  typedef service-sub-layer-ref {
    type leafref {
      path "/ietf-detnet:service-sub-layer"
         + "/ietf-detnet:service-sub-layer-list"
         + "/ietf-detnet:name";
    }
  }

  typedef forwarding-sub-layer-ref {
    type leafref {
      path "/ietf-detnet:forwarding-sub-layer"
         + "/ietf-detnet:forwarding-sub-layer-list"
         + "/ietf-detnet:name";
    }
  }

  typedef sub-network-ref {
    type leafref {
      path "/ietf-detnet:sub-network"
         + "/ietf-detnet:sub-network-list"
         + "/ietf-detnet:name";
    }
  }

  typedef ipsec-spi {
    type uint32 {
      range "1..max";
    }
    description
      "SPI";
  }

  typedef service-operation-type {
    type enumeration {
      enum service-initiation {
        description
          "Operation for DetNet service sub-layer encapsulation";
      }
      enum service-termination {
        description
          "Operation for DetNet service sub-layer decapsulation";
      }
      enum service-relay {
        description
          "Operation for DetNet service sub-layer swap";
      }
      enum non-detnet {
        description
          "No operation for DetNet service sub-layer";
      }
    }
  }

  typedef mpls-operations-type {
    type enumeration {
      enum impose-and-forward {
        description
          "Operation impose outgoing label(s) and forward to
           next-hop";
      }
      enum pop-and-forward {
        description
          "Operation pop incoming label and forward to next-hop";
      }
      enum pop-impose-and-forward {
        description
          "Operation pop incoming label, impose one or more
           outgoing label(s) and forward to next-hop";
      }
      enum swap-and-forward {
        description
          "Operation swap incoming label, with outgoing label and
           forward to next-hop";
      }
      enum pop-and-lookup {
        description
          "Operation pop incoming label and perform a lookup";
      }
    }
    description "MPLS operations types";
  }
  
  typedef service-protection-type {
    type enumeration {
      enum none {
        description
          "no service protection provide";
      }
      enum replication {
        description
          "A Packet Replication Function (PRF) replicates
           DetNet flow packets and forwards them to one or
           more next hops in the DetNet domain.  The number
           of packet copies sent to each next hop is a
           DetNet flow specific parameter at the node doing
           the replication.  PRF can be implemented by an
           edge node, a relay node, or an end system";
      }
      enum elimination {
        description
          "A Packet Elimination Function (PEF) eliminates
           duplicate copies of packets to prevent excess
           packets flooding the network or duplicate
           packets being sent out of the DetNet domain.
           PEF can be implemented by an edge node, a relay
           node, or an end system.";
      }
      enum ordering {
        description
          "A Packet Ordering Function (POF) re-orders
           packets within a DetNet flow that are received
           out of order.  This function can be implemented
           by an edge node, a relay node, or an end system.";
      }
      enum elimination-ordering {
        description
          "A combination of PEF and POF that can be
           implemented by an edge node, a relay node, or
           an end system.";
      }
      enum elimination-replication {
        description
          "A combination of PEF and PRF that can be
           implemented by an edge node, a relay node, or
           an end system";
      }
      enum elimination-ordering-replicaiton {
        description
          "A combination of PEF, POF and PRF that can be
           implemented by an edge node, a relay node, or
           an end system";
      }
    }
  }

  typedef sequence-number-generation-type {
    type enumeration {
      enum copy-from-app-flow {
        description
          "Copy the app-flow sequence number to the DetNet-flow";
      }
      enum generate-by-detnet-flow {
        description
          "Generate the sequence number by DetNet flow";
      }
    }
  }

  typedef sequence-number-field {
    type enumeration {
      enum zero-sn {
        description "there is no DetNet sequence number field.";
      }
      enum short-sn {
        description "there is 16bit DetNet sequence number field";
        value 16;
      }
      enum long-sn {
        description "there is 28bit DetNet sequence number field";
        value 28;
      }
    }
  }  

  grouping ip-header {
    description
      "The IPv4/IPv6 packet header information";
    leaf src-ip-address {
      type inet:ip-address;
      description
        "The source IP address of the header";
    }
    leaf dest-ip-address {
      type inet:ip-address;
      description
        "The destination IP address of the header";
    }
    leaf next-header {
      type uint8;
      description
        "The next header of the IPv6 header";
    }
    leaf traffic-class {
      type uint8;
      description
        "The traffic class value of the header";
    }
    leaf flow-label {
      type inet:ipv6-flow-label;
      description
        "The flow label value of the header";
    }
    leaf source-port {
      type inet:port-number;
      description
      "The source port number";
    }
    leaf destination-port {
      type inet:port-number;
      description
      "The destination port number"; 
    }
  }

  grouping l2-header {
    description
      "The Ethernet or TSN packet header information";
    leaf source-mac-address {
      type yang:mac-address;
      description
        "The source MAC address value of the ethernet header";
    }
    leaf destination-mac-address {
      type yang:mac-address;
      description
        "The destination MAC address value of the ethernet header";
    }
    leaf ethertype {
      type eth:ethertype;
      description
        "The ethernet packet type value of the ethernet header";
    }
    leaf vlan-id {
      type uint16;
      description
        "The Vlan value of the ethernet header";
    }
    leaf pcp {
      type uint8;
      description
        "The priority value of the ethernet header";
    }
  }
  grouping destination-ip-port-identification {
    description
    "The TCP/UDP port(source/destination) identification information";
      container destination-port {
      uses packet-fields:port-range-or-operator;
      }
  }

  grouping source-ip-port-identification {
    description
    "The TCP/UDP port(source/destination) identification information";
      container source-port {
      uses packet-fields:port-range-or-operator;
      }
  }

  grouping ip-flow-identification {
    description
    "The IPv4/IPv6 packet header identification information";
    leaf src-ip-prefix {
      type inet:ip-prefix;
      description
      "The source IP address of the header";
    }
    leaf dest-ip-prefix {
      type inet:ip-prefix;
      description
      "The destination IP address of the header";
    }
    leaf next-header {
      type uint8;
      description
      "The next header of the IPv6 header";
    }
    leaf traffic-class {
      type uint8;
      description
      "The traffic class value of the header";
    }
    leaf flow-label {
      type inet:ipv6-flow-label;
      description
      "The flow label value of the header";
    }
      uses source-ip-port-identification;
      uses destination-ip-port-identification;
    leaf ipsec-spi {
      type ipsec-spi;
      description "Security parameter index of SA entry";
    }
  }

  grouping mpls-flow-identification {
    description
    "The MPLS packet header identification information";
    choice label-space {
      description "";
      case non-platrom-label-space {
        uses rt-types:mpls-label-stack;
      }
      case platform-label-space {
        leaf label {
          type rt-types:mpls-label;
        }
      }
    }
  }

  grouping traffic-specification {
    container traffic-specification {
    description
      "traffic-specification specifies how the Source
       transmits packets for the flow.  This is the
       promise/request of the Source to the network.
       The network uses this traffic specification
       to allocate resources and adjust queue
       parameters in network nodes.";
    reference
      "draft-ietf-detnet-flow-information-model";
    leaf interval {
      type uint32;
        description
          "The period of time in which the traffic
           specification cannot be exceeded";
    }
    leaf max-packets-per-interval{
      type uint32;
      description
        "The maximum number of packets that the
         source will transmit in one Interval.";
    }
    leaf max-payload-size{
      type uint32;
      description
        "The maximum payload size that the source
         will transmit.";
    }
    leaf average-packets-per-interval {
      type uint32;
      description
        "The average number of packets that the
         source will transmit in one Interval";
    }
    leaf average-payload-size {
      type uint32;
      description
        "The average payload size that the
         source will transmit.";
    }
    }
  }

  grouping traffic-requirements {
    container traffic-requirements {
      description
        "FlowRequirements: defines the attributes of the App-flow
        regarding bandwidth, latency, latency variation, loss, and
        misordering tolerance.";
      leaf min-bandwidth {
        type uint64;
        description
          "MinBandwidth is the minimum bandwidth that has to be
          guaranteed for the DetNet service.  MinBandwidth is
          specified in octets per second.";
      }
      leaf max-latency {
        type uint32;
        description
          "MaxLatency is the maximum latency from Ingress to Egress(es)
          for a single packet of the DetNet flow.  MaxLatency is
          specified as an integer number of nanoseconds"; 
      }
      leaf max-latency-variation {
        type uint32;
        description
          "MaxLatencyVariation is the difference between the minimum and
          the maximum end-to-end one-way latency.  MaxLatencyVariation
          is specified as an integer number of nanoseconds.";
      }
      leaf max-loss {
        type uint8;
        description
          "MaxLoss defines the maximum Packet Loss Ratio (PLR) parameter
          for the DetNet service between the Ingress and Egress(es) of
          the DetNet domain.";
      }
      leaf max-consecutive-loss-tolerance {
        type uint32;
        description
          "Some applications have special loss requirement, such as
          MaxConsecutiveLossTolerance.  The maximum consecutive loss
          tolerance parameter describes the maximum number of
          consecutive packets whose loss can be tolerated.  The maximum
          consecutive loss tolerance can be measured for example based
          on sequence number";
      }
      leaf max-misordering {
        type uint32;
        description
          "MaxMisordering describes the tolerable maximum number of
          packets that can be received out of order.  The maximum
          allowed misordering can be measured for example based on
          sequence number.  The value zero for the maximum allowed
          misordering indicates that in order delivery is required,
          misordering cannot be tolerated.";
      }
      }
  }
  
  grouping data-flow-spec {
    description "app-flow identification";
    choice data-flow-type {
      case tsn-app-flow {
        uses l2-header;
      }
      case ip-app-flow {
        uses ip-flow-identification;
      }
      case mpls-app-flow {
        uses mpls-flow-identification;
      }
    }
  }
  grouping detnet-flow-spec {
    description "detnet-flow identificatioin";
    choice detnet-flow-type {
      case ip-detnet-flow {
        uses ip-flow-identification;
      }
      case mpls-detnet-flow {
        uses mpls-flow-identification;
      }
    }
  }

  grouping app-flows-ref {
    description "incoming or outgoing app-flow reference group";
    leaf-list app-flow {
      type app-flow-ref;
      description "List of ingress or egress app-flows";
    }
  }

  grouping incoming-detnet-flows {
    description "incoming detnet member flows identification";
    list incoming-detnet-flow {
      key "incoming-index";
      description "";
      leaf incoming-index {
        type uint8;
        description "";
      }
      uses detnet-flow-spec;
    }
  }

  grouping detnet-header {
    description "DetNet header info for DetNet encapsulation or forwarding";
    choice header-type {
      case detnet-mpls-header {
        description
          "MPLS label stack for DetNet MPLS encapsulation or forwarding";
        uses rt-types:mpls-label-stack;
      }
      case detnet-ip-header {
        description
          "IPv4/IPv6 packet header for DetNet IP encapsulation";
        uses ip-header;
      }
    }
  }

  grouping lower-layer-ref {
    choice lower-layer-type {
      case service-sub-layer {
        leaf service-sub-layer {
          type service-sub-layer-ref;
        }
      }
      case forwarding-sub-layer {
        leaf forwarding-sub-layer {
          type forwarding-sub-layer-ref;
        }
      }
      case sub-network {
        leaf sub-network {
          type sub-network-ref;
        }
      }
      case interface {
        leaf outgoing-interface {
          type if:interface-ref;
        }
      }
    }
  }
  grouping detnet-next-hop-content {
    description
      "Generic parameters of DetNet next hops.";
    choice next-hop-options {
      mandatory true;
      description
        "Options for next hops.
         It is expected that further cases will be added through
         augments from other modules, e.g., for recursive
         next hops.";
      case simple-next-hop {
        description
          "This case represents a simple next hop consisting of the
           next-hop address and/or outgoing interface.
           Modules for address families MUST augment this case with a
           leaf containing a next-hop address of that address
           family.";
        uses detnet-header;
   list lower-layer{
          key "index";
   description "lower-layer info";
          leaf index {
            type uint8;
          }
          uses lower-layer-ref;
   }
      }
      case next-hop-list {
        container next-hop-list {
          description
            "Container for multiple next hops.";
          list next-hop {
            key "hop-index";
            description
              "An entry in a next-hop list.

               Modules for address families MUST augment this list
               with a leaf containing a next-hop address of that
               address family.";
            leaf hop-index {
              type uint8; 
              description "";
            } 
            uses detnet-header;
     list lower-layer{
              key "index";
       description "lower-layer info";
              leaf index {
                type uint8;
              }
              uses lower-layer-ref;
     }
          }      
        }        
      }          
    }            
  } 


  container app-flows {
    description
    "The DetNet app-flow configuration";
    list app-flow {
      key "name";
      description "";
      leaf name {
        type "string";
        description "The name to identify the DetNet app-flow";
      }
      container end-points {
      leaf source-endpoint {
        type inet:ip-address;
        description
        "The DetNet application endpoint source address";
      }
      leaf-list destination-endpoints {
        type inet:ip-address;
        description
        "The DetNet application endpoint destination address list";
      }
      }
      leaf app-flow-bidir-congruent {
        type boolean;
        description 
        "Defines the data path requirement of the App-flow whether it must share the same data path and physical path for both directions through the network, e.g., to provide congruent paths in the two directions.";
      }
      uses traffic-requirements;
      uses traffic-specification;
      container in-segment {
   description "";
            list app-traffic {
            key "interface";
         description "";
        leaf interface {
           type if:interface-ref;
           description "";
        }
         uses data-flow-spec;
       }
      }
      container out-segment {
       description 
                "detnet-flows that must be mapped to received app-flow or route for outgoing app-flow";
       uses detnet-next-hop-content;
      }
    }
  }
  container service-sub-layer {
    description "The DetNet service sub-layer configuration";
    list service-sub-layer-list {
      key "name";
      description "";
      leaf name {
        type string;
        description "The name of the DetNet service sub-layer";
      }
      leaf service-id {
        type uint16;
        config false;
        description
          "The DetNet service ID";
      }
      leaf service-rank {
        type uint8;
        description
          "The DetNet rank for this service";
      }
      uses traffic-requirements;
      container service-portection {
       leaf service-protection-type {
        type service-protection-type;
        description 
        "The DetNet service protection type such as PRF, PEF, PEOF,PERF, and PEORF";
        }
      leaf sequence-number-length {
       type sequence-number-field;
      description "sequence number filed can choice 0 bit, 16bit, 28 bit filed"; 
       }
       leaf sequence-number-window-size {
       type uint32; 
       description "sequence number window size";
       }
       leaf sequence-number-generation {
       type sequence-number-generation-type;
       description "config sequence number source";
       }
      }
      leaf service-operation-type {
        type service-operation-type;
      }
      container in-segment {
            uses app-flows-ref;
            uses incoming-detnet-flows;
      }
      container out-sergment {
            uses detnet-next-hop-content;
            uses app-flows-ref;
      }
    }
  }
  container forwarding-sub-layer {
    description "The DetNet forwarding sub-layer configuration";
    list forwarding-sub-layer-list {
      key "name";
      description "";
      leaf name {
        type string;
        description "The name of the DetNet forwarding sub-layer";
      }
      container resource-allocation {
        uses traffic-specification;
      }
      leaf forwarding-operation-type {
        type mpls-operations-type;
      }
      container in-segment {
        leaf service-sub-layer {
          type service-sub-layer-ref;
          description "";
        }
        list forwarding-traffic {
          key "interface";
          description "";
          leaf interface {
            type if:interface-ref;
            description "";
          }
          uses detnet-flow-spec;
        }
      }
      container out-segment {
        uses detnet-next-hop-content;
        leaf service-sub-layer {
          type service-sub-layer-ref;
          description "";
        }
      }
    }
  }
  container sub-network {
    description "";
    list sub-network-list {
      key "name";
      description "";
      leaf name {
        type string;
        description "";
      }
    }
  }
}

7. Open Issues

There are some open issues that are still under discussion:

• The name of 'in-segment' and 'out-segment' are still under discussion. These terms are used in YANG model for MPLS, but they may cause confusion in DetNet.
• Whether application flow should be in service sub-layer is still under discussion.
• Whether we are supposed to define a new YANG Model for DetNet as the current draft does, or we should augment the current YANG Model.

These issues will be resolved in the following versions of the draft.

8. IANA Considerations

This document makes no request of IANA.

Note to RFC Editor: this section may be removed on publication as an RFC.

9. Security Considerations

<TBD>

10. Acknowledgements

11. References

11.1. Normative References

11.2. Informative References

Authors' Addresses