| Internet-Draft | Network Inventory Topology | August 2024 |
| Wu, et al. | Expires 8 February 2025 | [Page] |
This document defines a YANG model for network inventory topology to correlate the network inventory data with the general topology model 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 data of the underlay network for agile service provisioning and network maintenance analysis.¶
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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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
[I-D.ietf-ivy-network-inventory-yang] defines base Network Inventory (NI) model to aggregate the inventory data of the Network Elements (NEs) on the network, which includes NEs and their hardware components, firmware components, and software components. 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 mapping, 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.¶
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.¶
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 topology 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 |
+-------------------------------------------+
[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 topology 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.¶
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-mapping!
augment /nw:networks/nw:network/nw:node:
+--rw inventory-mapping-attributes
+--rw node-name? string
+--ro ne-ref? ne-ref
+--rw system-mount-point
augment /nw:networks/nw:network/nt:link:
+--rw inventory-mapping-attributes
+--rw link-name? string
+--ro cable-name? string
+--ro link-type? string
augment /nw:networks/nw:network/nw:node/nt:termination-point:
+--rw inventory-mapping-attributes
+--ro tp-name? string
+--ro port-component-ref? leafref
+--rw interface-name* string
+--rw system-mount-point
The module augments the original "ietf-network- topology" modules as follows:¶
A new network topology type: "network-inventory-mapping". The corresponding container augments the network-types of the "ietf-network" module.¶
Inventory mapping attributes for nodes, links, and termination points: The corresponding containers augments the topology module with the references to the base network inventory, references to interface management, and system mount points .¶
Being an independent underlaying topology, the inventory topology model associates inventory data with abstract topologies. It can be used as the "supporting-networks" of SAP, Layer 2, or Layer 3 topologies.¶
The "ietf-network-inventory-topology" module uses types defined in [RFC8345].¶
<CODE BEGINS> file="[email protected]" 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"; } import ietf-network-inventory { prefix nwi; reference "RFC AAAA: A YANG Data Model for Network Inventory"; } organization "IETF Network Inventory YANG (ivy) Working Group"; contact "WG Web: <https://datatracker.ietf.org/wg/ivy> WG List: <mailto:[email protected]> Editor: Bo Wu <[email protected]> Editor: Cheng Zhou <[email protected]> Editor: Qin Wu <[email protected]> Editor: Mohamed Boucadair <[email protected]>"; description "This YANG module defines XXX. Copyright (c) 2024 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 2024-04-29 { description "Initial revision."; reference "RFC XXXX: A YANG Data Model for Network Inventory Mapping Topology"; } /* Identities */ /* Typedef */ typedef ne-ref { type leafref { path "/nwi:network-inventory/nwi:network-elements" + "/nwi:network-element/nwi:ne-id"; } description "This type is used by data models that need to reference Network Element."; } /* Groupings */ grouping inventory-mapping-network-type { description "Indicates the topology type to be Network Inventory mapping."; container network-inventory-mapping { presence "Indicates Network Inventory mapping topology."; description "The presence of the container node indicates Network Inventory mapping."; } } grouping system-mount-point { description "Indicates system configuration or state mount point."; container system-mount-point { description "Container for system configuration or state mount point."; } } grouping node-inventory-attributes { description "Network Inventory mapping node scope attributes"; container inventory-mapping-attributes { description "The container node attributes of Network Inventory mapping."; leaf node-name { type string; description "The name of the node."; } leaf ne-ref { type ne-ref; config false; description "The reference of the Network Element (NE) from which this node is abstracted."; } uses system-mount-point; } } grouping termination-point-inventory-attributes { description "Network Inventory mapping termination point (TP) scope attributes"; container inventory-mapping-attributes { description "The container TP attributes of Network Inventory mapping."; leaf tp-name { type string; config false; description "The name of the TP."; } leaf port-component-ref { type leafref { path "/nwi:network-inventory/nwi:network-elements" + "/nwi:network-element[nwi:ne-id=current()/../../../" + "inventory-mapping-attributes/ne-ref]/nwi:components" + "/nwi:component/nwi:component-id"; } config false; description "The reference of the port component from which this termination point is abstracted."; } leaf-list 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; } } grouping link-inventory-attributes { description "Network Inventory mapping link scope attributes"; container inventory-mapping-attributes { description "The container link attributes of network inventory mapping."; leaf link-name { type string; description "The name of the link."; } leaf cable-name { type string; config false; description "The reference of the cable inventory from which this link is abstracted Note: this will be changed based on the future inventoy cable model."; } leaf link-type { type string; config false; description "The type of the link. Note: this will be changed based on the future inventoy cable model."; } } } /* Main blocks */ augment "/nw:networks/nw:network/nw:network-types" { description "Introduces new network type for network inventory mapping."; uses inventory-mapping-network-type; } augment "/nw:networks/nw:network/nw:node" { when '/nw:networks/nw:network/nw:network-types/ nwit:network-inventory-mapping' { description "Augmentation parameters apply only for network inventory mapping."; } description "Configuration parameters for inventory at the node level."; uses node-inventory-attributes; } augment "/nw:networks/nw:network/nt:link" { when '/nw:networks/nw:network/nw:network-types/ nwit:network-inventory-mapping' { description "Augmentation parameters apply only for network inventory."; } description "Augments inventory topology link information."; uses link-inventory-attributes; } augment "/nw:networks/nw:network/nw:node/nt:termination-point" { when '/nw:networks/nw:network/nw:network-types/ nwit:network-inventory-mapping' { description "Augmentation parameters apply only for network inventory."; } description "Augments inventory termination point information."; uses termination-point-inventory-attributes; } } <CODE ENDS>¶
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>>>¶
The model includes sensitive PII data. More to be discussed:¶
Data related to BYOD devices¶
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
¶
The authors wish to thank Italo Busi, Olga Havel, Aihua Guo, Oscar Gonzalez de Dios, and many others for their helpful comments and suggestions.¶
The following authors contributed significantly to this document:¶
Chaode Yu Huawei Technologies Email: [email protected]¶
The "ietf-network-inventory-topology" provides the topology mapping with the network inventory by using references. This design does not impact the existing topology models.¶
This appendix also introduces a YANG module that defines a simple topology model for network inventory reference. This module is intended to serve as an example that illustrates how the general topology model can be refined with inventory references across multiple levels of topology, e.g. TE topology, Layer 2 topology, Layer 3 topology, service attachment points (SAPs) topology.¶
Figure 3 below shows the tree diagram of the YANG data model defined in module "example-topo-inventory-ref"¶
module: example-topology-inv-ref
augment /nw:networks/nw:network/nw:node:
+--ro ne-reference? ne-ref
augment /nw:networks/nw:network/nw:node/nt:termination-point:
+--ro port-component-ref? leafref
The Topology Inventory Reference YANG module is specified below. As mentioned, the module is intended as an example for how the topology model can be extended to cover inventory references, but it is only for discusson. Accordingly, the module is not delimited with <CODE BEGINS> and <CODE ENDS> tags.¶
module example-topology-inv-ref {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:example-topology-inv-ref";
prefix nwir;
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";
}
import ietf-network-inventory {
prefix nwi;
reference
"RFC AAAA: A YANG Data Model for Network Inventory";
}
description
"This module is intended as an example for how the
base topology model can be extended to cover
inventory references.";
/* Main blocks */
augment "/nw:networks/nw:network/nw:node" {
description
"Information that allows the relationship between the node in
the topology and the Network Element (NE) in the network
inventory model from which the node is abstracted";
leaf ne-ref {
type leafref {
path "/nwi:network-inventory/nwi:network-elements"
+ "/nwi:network-element/nwi:ne-id";
}
config false;
description
"The reference of the Network Element (NE) from which this
node is abstracted";
}
}
augment
"/nw:networks/nw:network/nw:node/nt:termination-point" {
description
"Information that allows the relationship between the
Termination Point (TP) and the port component in the network
inventory model from which this TP is abstracted.";
leaf port-component-ref {
type leafref {
path "/nwi:network-inventory/nwi:network-elements"
+ "/nwi:network-element[nwi:ne-id=current()/../../"
+ "ne-ref]/nwi:components/nwi:component"
+ "/nwi:component-id";
}
config false;
description
"The reference of the port component from which this
Termination Point (TP) is abstracted";
}
}
}¶
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 4 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 |
+-------------------------+ +---------------------------+
With the inventory data collected from the underlying network, the network orchestration system can centrally manage security and network policies related to network endpoints.¶