Internet-Draft Network Inventory Topology October 2023
Wu, et al. Expires 20 April 2024 [Page]
Workgroup:
IVY
Internet-Draft:
draft-wzwb-ivy-network-inventory-topology-00
Published:
Intended Status:
Standards Track
Expires:
Authors:
B. Wu
Huawei
C. Zhou
China Mobile
Q. Wu
Huawei
M. Boucadair
Orange

A Network Inventory Topology Model

Abstract

This document defines a YANG model for network inventory topology to correlate the network inventory with the general topology to form a base underlay network, which can facilitate the mapping and correlation of the layer (e.g. Layer 2, Layer3) topology information above to the inventory resource of the underlay network for agile service provisioning and network maintenance analysis.

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 20 April 2024.

▲

Table of Contents

1. Introduction

The Network Inventory supports the inventory management of all the network devices, hardware components, firmware components, and software components on the a managed network domain. Examples of inventory hardware components could be rack, shelf, slot, board and physical port. Examples of inventory software components could be platform operating system (OS), software-patch, bios, and boot-loader.

This document extends the RFC 8345 network topology model for network inventory references, which facilitates the correlation with existing network and topology models, such as SAP [RFC9408], L2 topology [RFC8944], and L3 topology [RFC8346], to support agile service provisioning and network maintenance.

In addition, the network inventory topology can also provide anchor points to mount specific device configuration and state information, e.g. QoS policies, ACL policies, to support configuration verification of cross-domain policies.

2. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119][RFC8174] when, and only when, they appear in all capitals, as shown here.

3. Sample Use Cases

3.1. Determin Available Resource of Service Attachment Points (SAPs)

The inventory topology model can be used as a base to correlate underlay information, such as physical port components. The figure belows gives an example of the usage.

During service provisioning, to check available physical port resources, the Service Attachment Points (SAPs) information can be associated with the underlay inventory information and interface information associated with the inventory topology, e.g. "parent-termination-point" of SAP Model can be associated with the "port-component-ref" and "interface-name" of the inventory model, which can be used to check the availability and capacity of physical ports.

                     +-----------------+
                     |     Customer    |
                     +--------+--------+
     Customer Service Models  |
        (e.g., L3SM, L2SM)    |
                     +--------+--------+
                     |    Service      |
                     |  Orchestration  |
                     +------+---+------+
                            |   |
          SAP Network Model |   | Inventory Topology Model
                     +------+---+------+
                     |     Network     |
                     |   Controller    |
                     +--------+--------+
                              |
        +---------------------+---------------------+
        |                  Network                  |
        +-------------------------------------------+
Figure 1: An Example Usage of Network Inventory Topology

3.2. The Example Digital Twin Network

[I-D.irtf-nmrg-network-digital-twin-arch] defines "digital twin network" as a virtual representation of the physical network. Such virtual representation of the network is meant to be used to analyze, diagnose, emulate, and then manage the physical network based on data, models, and interfaces.

The management system can use digital twin technology to build visual multi-layer topology maps for networks and endpoints with relationship types and dependencies, and identify potential impacts on configuration management information from incidents, problems, and changes.

The inventory model can, for example, be used to emulate several what-if scenario such as the impact of EOL or depletion of a hardware component on the network resilience and service availability.

4. Model Overview

The following tree diagram [RFC8340] provides an overview of the data model for "ietf-network-inventory-topology" module.

module: ietf-network-inventory-topology
  augment /nw:networks/nw:network/nw:network-types:
    +--rw network-inventory!

  augment /nw:networks/nw:network/nw:node:
    +--rw name?                            string
    +--ro node-type?                       identityref
    +--ro network-element-inventory-ref*   -> /nwi:network-elements/network-element/name
    +--rw system-mount-point
    +--ro oper-state?                      oper-state

  augment /nw:networks/nw:network/nt:link:
    +--ro link-name?          string
    +--ro cable-ref?          -> /nwi:cables/cable/name
    +--ro link-description?   string
    +--ro link-type?          string
    +--ro oper-state?         oper-state

  augment /nw:networks/nw:network/nw:node/nt:termination-point:
    +--ro tp-name?                        string
    +--ro tp-description?                 string
    +--ro tp-type?                        identityref
    +--ro port-component-inventory-ref?   -> /nwi:network-elements/network-element/components/component/name
    +--rw interface-name?                 string
    +--rw system-mount-point
    +--ro oper-state?                     oper-state

5. YANG Data model for Network Inventory Topology

The "ietf-network-inventory-topology" module uses types defined in [RFC8345].

<CODE BEGINS> file="ietf-network-inventory-topology@2023-10-18.yang"
module ietf-network-inventory-topology {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology";
  prefix nwit;

  import ietf-network {
    prefix nw;
    reference
      "RFC 8345: A YANG Data Model for Network Topologies";
  }
  import ietf-network-topology {
    prefix nt;
    reference
      "RFC 8345: A YANG Data Model for Network Topologies";
  }

  organization
    "IETF Network Inventory YANG (ivy) Working Group";
  contact
    "WG Web:   <https://datatracker.ietf.org/wg/ivy>
     WG List:  <mailto:inventory-yang@ietf.org>

     Editor: Bo Wu
          <lana.wubo@huawei.com>
     Editor: Cheng Zhou
          <zhouchengyjy@chinamobile.com>
     Editor: Qin Wu
          <bill.wu@huawei.com>
     Editor: Mohamed Boucadair
          <mohamed.boucadair@orange.com>";
  description
    "This YANG module defines XXX.

     Copyright (c) 2023 IETF Trust and the persons identified
     as authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX
     (https://www.rfc-editor.org/info/rfcXXXX); see the RFC
     itself for full legal notices.";

  revision 2023-10-18 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for Network Inventory Topology";
  }

  identity node-type {
    description
      "Base identity for node device type.";
  }

  identity switch {
    base node-type;
    description
      "Identity for switch device.";
  }

  identity router {
    base node-type;
    description
      "Identity for router device.";
  }

  identity firewall {
    base node-type;
    description
      "Identity for Firewall device.";
  }

  identity access-controller {
    base node-type;
    description
      "Identity for WIFI access controller device.";
  }

  identity access-point {
    base node-type;
    description
      "Identity for WIFI access point device.";
  }

  identity sdn-controller {
    base node-type;
    description
      "Identity for controller.";
  }

  identity server {
    base node-type;
    description
      "Identity for computing server device.";
  }

  identity vm {
    base node-type;
    description
      "Identity for VM node.";
  }

  identity camera {
    base node-type;
    description
      "Identity for camera device.";
  }

  identity printer {
    base node-type;
    description
      "Identity for camera device.";
  }

  identity cell-phone {
    base node-type;
    description
      "Identity for mobile phone.";
  }

  identity port-type {
    description
      "Base identity for device port type.";
  }

  typedef oper-state {
    type enumeration {
      enum unknown {
        value 1;
        description
          "The resource is unable to report its operational
           state.";
      }
      enum disabled {
        value 2;
        description
          "The resource is totally inoperable.";
      }
      enum enabled {
        value 3;
        description
          "The resource is partially or fully operable.";
      }
      enum testing {
        value 4;
        description
          "The resource is currently being tested and cannot
           therefore report whether or not it is operational.";
      }
    }
    description
      "Represents the possible values of operational states.";
    reference
      "RFC 4268: Entity State MIB - EntityOperState";
  }

  /* Groupings */

  grouping inventory-network-type {
    description
      "Indicates the topology type to be inventory.";
    container network-inventory {
      presence "Indicates Network Inventory.";
      description
        "The presence of the container node indicates
         Network Inventory.";
    }
  }

  grouping system-mount-point {
    container system-mount-point {
      description
        "Container for system configuration or state mount-point.";
    }
  }

  grouping inventory-node-attributes {
    description
      "Augment used to define attach the node configuration";
    leaf name {
      type string;
      description
        "The name of the node.";
    }
    leaf node-type {
      type identityref {
        base node-type;
      }
      config false;
      description
        "Node type.";
    }
    leaf-list network-element-inventory-ref {
      type leafref {
        path "/nwi:network-elements"
           + "/nwi:network-element/nwi:name";
      }
      config false;
      description
        "The reference of the Network Elements (NEs) from which this
         node is abstracted. For example, in the case of cluster device,
         one node can abstract multiple NEs.";
    }
    uses system-mount-point;
    leaf oper-state {
      type oper-state;
      config false;
      description
        "The operational state for this component.
         Note that this node does not follow the administrative
         state.  An administrative state of 'down' does not
         predict an operational state of 'disabled'.
         Note that some implementations may not be able to
         accurately report oper-state while the admin-state node
         has a value other than 'unlocked'.  In these cases, this
         node MUST have a value of 'unknown'.";
      reference
        "RFC 4268: Entity State MIB - entStateOper";
    }
  }

  grouping inventory-termination-point-attributes {
    description
      "Augment used to define attach the termination point
       attributes.";
    leaf tp-name {
      type string;
      config false;
      description
        "The name of the interface.";
    }
    leaf tp-description {
      type string;
      config false;
      description
        "A textual description of the interface.";
    }
    leaf tp-type {
      type identityref {
        base port-type;
      }
      config false;
      description
        "The port type of the interface, e.g. console port";
    }
    leaf port-component-inventory-ref {
      type leafref {
        path "/nwi:network-elements/nwi:network-element/"
           + "nwi:components/nwi:component/nwi:name";
      }
      config false;
      description
        "The reference of the port component from which this
         termination point is abstracted.";
    }
    leaf interface-name {
      type string;
      description
        "Name of the interface.  The name can (but does not
         have to) correspond to an interface reference of a
         containing node's interface, i.e., the path name of a
         corresponding interface data node on the containing
         node is reminiscent of data type interface-ref defined
         in RFC 8343.  It should be noted that data type
         interface-ref of RFC 8343 cannot be used directly,
         as this data type is used to reference an interface
         in a datastore of a single node in the network, not
         to uniquely reference interfaces across a network.";
    }
    uses system-mount-point;
    leaf oper-state {
      type oper-state;
      config false;
      description
        "The operational state for this component.
         Note that this node does not follow the administrative
         state.  An administrative state of 'down' does not
         predict an operational state of 'disabled'.
         Note that some implementations may not be able to
         accurately report oper-state while the admin-state node
         has a value other than 'unlocked'.  In these cases, this
         node MUST have a value of 'unknown'.";
      reference
        "RFC 4268: Entity State MIB - entStateOper";
    }
  }

  grouping inventory-link-attributes {
    description
      "Augment used to define attach the termination point
       attributes.";
    leaf link-name {
      type string;
      config false;
      description
        "The name of the link.";
    }
    leaf cable-ref {
      type leafref {
        path "/nwi:cables/nwi:cable/nwi:name";
      }
      config false;
      description
        "The reference of the cable inventory information from which
         this link is abstracted.";
    }
    leaf link-description {
      type string;
      config false;
      description
        "A textual description of the interface.";
    }
    leaf link-type {
      type string;
      config false;
      description
        "The type of the link.";
    }
    leaf oper-state {
      type oper-state;
      config false;
      description
        "The operational state for this link.";
    }
  }

  /* Main blocks */

  augment "/nw:networks/nw:network/nw:network-types" {
    description
      "Introduces new network type for network inventory.";
    uses inventory-network-type;
  }

  augment "/nw:networks/nw:network/nw:node" {
    when '/nw:networks/nw:network/nw:network-types/
   nwit:network-inventory' {
      description
        "Augmentation parameters apply only for network inventory.";
    }
    description
      "Configuration parameters for inventory at the node
       level.";
    uses inventory-node-attributes;
  }

  augment "/nw:networks/nw:network/nt:link" {
    when '/nw:networks/nw:network/nw:network-types/
     nwit:network-inventory' {
      description
        "Augmentation parameters apply only for network
         inventory.";
    }
    description
      "Augments inventory topology link information.";
    uses inventory-link-attributes;
  }

  augment
    "/nw:networks/nw:network/nw:node/nt:termination-point" {
      when '/nw:networks/nw:network/nw:network-types/
     nwit:network-inventory' {
        description
          "Augmentation parameters apply only for network
           inventory.";
      }
      description
        "Augments inventory termination point information.";
      uses inventory-termination-point-attributes;
  }
}



<CODE ENDS>

6. Security Considerations

The YANG module specified in this document defines a data schema designed to be accessed through network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the required secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the required secure transport is TLS [RFC8446].

The Network Configuration Access Control Model (NACM) [RFC8341] provides a means of restricting access to specific NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and contents. Thus, NACM SHOULD be used to restrict the NSF registration from unauthorized users.

There are a number of data nodes defined in this YANG module that are writable, creatable, and deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations to these data nodes could have a negative effect on network and security operations.

Some of the readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability:

<<<to be completed>>>

7. Privacy Considerations

The model includes sensitive PII data. More to be discussed:

8. IANA Considerations

This document registers a URI in the "IETF XML Registry" [RFC3688]. Following the format in [RFC3688], the following registration has been made.

     URI: urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology
     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[RFC7950] .

     name:         ietf-network-inventory-topology
     namespace:    urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology
     prefix:       nwit
     maintained by IANA:
     reference:    RFC xxxx

9. Acknowledgements

TBD

10. References

10.1. Normative References

[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/info/rfc2119>.
[RFC3688]
Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, , <https://www.rfc-editor.org/info/rfc3688>.
[RFC6241]
Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, , <https://www.rfc-editor.org/info/rfc6241>.
[RFC6242]
Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, , <https://www.rfc-editor.org/info/rfc6242>.
[RFC6991]
Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, , <https://www.rfc-editor.org/info/rfc6991>.
[RFC7950]
Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, , <https://www.rfc-editor.org/info/rfc7950>.
[RFC8040]
Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, , <https://www.rfc-editor.org/info/rfc8040>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/info/rfc8174>.
[RFC8341]
Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, , <https://www.rfc-editor.org/info/rfc8341>.
[RFC8345]
Clemm, A., Medved, J., Varga, R., Bahadur, N., Ananthakrishnan, H., and X. Liu, "A YANG Data Model for Network Topologies", RFC 8345, DOI 10.17487/RFC8345, , <https://www.rfc-editor.org/info/rfc8345>.
[RFC8348]
Bierman, A., Bjorklund, M., Dong, J., and D. Romascanu, "A YANG Data Model for Hardware Management", RFC 8348, DOI 10.17487/RFC8348, , <https://www.rfc-editor.org/info/rfc8348>.
[RFC8446]
Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, , <https://www.rfc-editor.org/info/rfc8446>.
[RFC9179]
Hopps, C., "A YANG Grouping for Geographic Locations", RFC 9179, DOI 10.17487/RFC9179, , <https://www.rfc-editor.org/info/rfc9179>.

10.2. Informative References

[I-D.ietf-opsawg-sap]
Boucadair, M., de Dios, O. G., Barguil, S., Wu, Q., and V. Lopez, "A YANG Network Model for Service Attachment Points (SAPs)", Work in Progress, Internet-Draft, draft-ietf-opsawg-sap-15, , <https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-sap-15>.
[I-D.irtf-nmrg-network-digital-twin-arch]
Zhou, C., Yang, H., Duan, X., Lopez, D., Pastor, A., Wu, Q., Boucadair, M., and C. Jacquenet, "Digital Twin Network: Concepts and Reference Architecture", Work in Progress, Internet-Draft, draft-irtf-nmrg-network-digital-twin-arch-03, , <https://datatracker.ietf.org/doc/html/draft-irtf-nmrg-network-digital-twin-arch-03>.
[RFC8340]
Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, , <https://www.rfc-editor.org/info/rfc8340>.
[RFC8346]
Clemm, A., Medved, J., Varga, R., Liu, X., Ananthakrishnan, H., and N. Bahadur, "A YANG Data Model for Layer 3 Topologies", RFC 8346, DOI 10.17487/RFC8346, , <https://www.rfc-editor.org/info/rfc8346>.
[RFC8944]
Dong, J., Wei, X., Wu, Q., Boucadair, M., and A. Liu, "A YANG Data Model for Layer 2 Network Topologies", RFC 8944, DOI 10.17487/RFC8944, , <https://www.rfc-editor.org/info/rfc8944>.
[RFC9408]
Boucadair, M., Ed., Gonzalez de Dios, O., Barguil, S., Wu, Q., and V. Lopez, "A YANG Network Data Model for Service Attachment Points (SAPs)", RFC 9408, DOI 10.17487/RFC9408, , <https://www.rfc-editor.org/info/rfc9408>.

Appendix A. Network Policy Management in Enterprise Network

Enterprise networks are becoming heterogenous and supporting a variety of device types, such as BYOD vs. enterprise-supplied devices, Internet of things (IoT) devices, IP phones, printers, IP cameras), OT (Operation Technology) devices (e.g., sensors), etc. Also, these networks are designed to support both localized applications and cloud-based applications (e.g., public cloud computing, storage, etc.), or hybrid applications. Also, means to access network resources are not anymore from within specific sites, but access can be granted from anywhere. Dedicated gateways and authorization procedures are being generalized.

This trend is observed for the medical, power, manufacturing, or other infrastructure industries. These networks host a large number of multi-vendor IoT or OT devices, with frequent additions and changes. These complex environments often expose unknown safety and reliability blind spots.

The endpoints connected to an Enterprise network lack unified modelling and lifecycle management, and different services are modelled, collected, processed, and stored separately. The same category of network device and network endpoints may be (repeatedly) discovered, processed, and stored. Therefore, the inventory is difficult to manage when they are tracked in different places. Maintaining a centralized and up-to-date inventory is a technical enabler in order to implement a coherent control strategy for all endpoint types connected to an Enterprise network.

Figure 2 shows an example of an enterprise network consisting of two network domains: one campus network domain and one cloud network domain. The inventory data in the network can include network infrastructure devices (such as routers, switchs, security devices) and network endpoints (such as IoT/OT devices, servers, laptop, mobile devices). The management systems or network controllers in different domains can automatically collect or discover the inventory by multiple approaches.

            +-------------------------------------+
            | Service/network   Orchestration     |
            +-------------------------------------+
                |                               |
                | Network Inventory Model       |
                | Network Inventory Topology Model
                |                               |
        +----------------+              +----------------+
        | Campus manager |              | SD-WAN manager |
        +----------------+              +-------+--------+
                |                               |
                |                               |
                |                               |
  +-------------------------+            +------+--------------------+
  |     Campus Domain #1    |            |     Cloud network         |
  |                         |            |                           |
  |-------+  +-----------+  |            | +-----------+   +-------+ |
  |+IT/OTs+- +  Router   +--+---------   +-+vRouter    +---+Service| |
  |-------+  +-----------+  |            | ------------+   +-------+ |
  |                         |            |                           |
  |Site A                   |            |             Cloud Site B  |
  +-------------------------+            +---------------------------+
Figure 2: An Example of Enterprise Network Inventory Management

With the inventory data collected from the underlying network, the network orchestration system can centrally manage security and network policies related to network endpoints.

Authors' Addresses

Bo Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing
Jiangsu, 210012
China
Cheng Zhou
China Mobile
Beijing
100053
China
Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing
Jiangsu, 210012
China
Mohamed Boucadair
Orange
Rennes 35000
France