Release: CX-Saturn (Current)

CX-0122 Item Stock Exchange 2.0.1

ABSTRACT

The raising and management of Item Stock data is the task of ERP systems. Accurate inventory management is a decisive factor for stable delivery capability for suppliers and an important component of secure production capability for customers. Continuous monitoring of the Item Stock between suppliers and customers ensures important information for the company's own production planning and management. This information exchange is key to early detect and evaluate supply shortage issues. Moreover, standardized interfaces between ERP systems often exist only for order planning and execution. However, the necessary exchanging this information manually e.g. by phone or e-mail is error-prone and slow. To mitigate inefficient and faulty communication, this document defines a standardized approach for exchanging Item Stock data in an interoperable manner. A common description of the Item Stock based on a standardized semantic definition is fundamental for facilitating such an exchange.

FOR WHOM IS THE STANDARD DESIGNED

COMPARISON WITH THE PREVIOUS VERSION OF THE STANDARD

Changes:

integration and usage of digital twins as defined in [CX-0002] Digital Twins in Catena-X
harmonization of aspect model in accordance with [CX-0126] Industry Core: Part Type
discontinuation of the proprietary API used in v1.0.0 of this standard
grammatical, spelling and semantic improvements

New Content:

added a note on the obligation of standard implementers to make aware that sensitive data is being handled, see [Chapter 2.1.3]

1 INTRODUCTION

This document defines the standardized exchange of Item Stock data within the Catena-X network. The Item Stock semantically is the actual quantity of reserved (here called allocated) material for a partner that has not yet been shipped from the supplier's site or has already arrived at the customer's site and has not yet been used for production. The semantic model is presented in the Aspect Model Notation with all individual fields, formats and associated JSON schema. The standardization of the ItemStock semantic model and an exchange API enables participants in the value chain to share information about material and product stock in a timely manner, thus ensuring that the possible solution space for mitigating a supply shortage is maximized.

The Item Stock is related to a business relationship between the partners (an order / call-off exists). Legal framework conditions and business aspects play an important role, for example in the context of multi-sourcing, where no horizontal exchange of information may take place. The aim of this standard is to ensure a secure exchange of stock data for active monitoring and the associated prevention of bottlenecks and shortages.

1.1 AUDIENCE & SCOPE

This section is non-normative

This standard is relevant for the following roles defined in [CX-OMW]:

Data Providers willing to provide Item Stock data
Data Consumers interested in requesting and receiving Item Stock data
Business Application Providers interested in providing solutions implementing this standard
Consulting Services Providers interested in supporting companies fulfilling the standard

The scope of this standard is only the Item Stock aspect model and API. It describes the exchange of Item Stock data through a connector in accordance to [CX-0018].

1.2 CONTEXT AND ARCHITECTURE FIT

This section is non-normative

A typical order-based procurement process includes a customer that places an order and a supplier fulfilling it. Material may be either on stock at the supplier's site when it has been produced and is ready to be shipped to the customer, or at the customer's site when it has been delivered and has not yet been used for production. Those kinds of inventories are referred to as Item Stock. Information about Item Stock quantities it is key to early detect and evaluate short-term supply shortages on the customer or supplier side. Also it can help reduce the total amount of stored material within the supply chain when partners share information on their materials inventory.

Figure 1 shows the high-level architecture of the Item Stock exchange in the Catena-X dataspace and the services that are involved. Both the data provider and the data consumer must be members of the Catena X network in order to communicate with each other. With the help of the Credential Service and the Identity Access Management (IAM) each participant can authenticate itself, verify the identity of the requesting party and decide whether to authorize the request. The Item Stock data is provisioned in accordance with [CX-0002].

Figure 1: High-level architecture of the Item Stock exchange in Catena-X

1.3 CONFORMANCE AND PROOF OF CONFORMITY

This section is non-normative

The sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative. The key words MAY , MUST , MUST NOT , OPTIONAL , RECOMMENDED , REQUIRED , SHOULD and SHOULD NOT 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.

All participants and their solutions will need to prove that they are conform with the Catena-X standards. To validate that the standards are applied correctly, Catena-X employs Conformity Assessment Bodies (CABs). The proof of conformity for a single semantic model is done according to the general rules for proving the conformity of data provided to a semantic model or the ability to consume the corresponding data. Furthermore participants agree to follow the normative language of this standardization document and to implement the required API-Endpoints described in Chapter 4.

1.4 EXAMPLES

The following example shows a value-only JSON serialization of the "ItemStock" aspect model. It represents a quantity of 20 pieces for an order position of a given material.

{
  "materialGlobalAssetId" : "urn:uuid:48878d48-6f1d-47f5-8ded-a441d0d879df",
  "positions" : [ {
    "orderPositionReference" : {
      "supplierOrderId" : "M-Nbr-4711",
      "customerOrderId" : "C-Nbr-4711",
      "customerOrderPositionId" : "PositionId-01"
    },
    "allocatedStocks" : [ {
      "isBlocked" : false,
      "stockLocationBPNA" : "BPNA1234567890ZZ",
      "lastUpdatedOnDateTime" : "2023-04-28T14:23:00.123456+14:00",
      "quantityOnAllocatedStock" : {
        "value" : 20.0,
        "unit" : "unit:piece"
      },
      "stockLocationBPNS" : "BPNS1234567890ZZ"
    } ]
  } ],
  "direction" : "INBOUND"
}

1.5 TERMINOLOGY

This section is non-normative

Name	Abrv.	Description
Business Partner Number	BPN	A BPN is the unique identifier of a partner within Catena-X as defined in [CX-0010].
Business Partner Number Legal Entity	BPNL	A BPNL is the unique identifier of a partner legal entity within Catena-X as defined in [CX-0010].
Business Partner Number Site	BPNS	A BPNS is the unique identifier of a partner site within Catena-X as defined in [CX-0010].
Business Partner Number Address	BPNA	A BPNA is the unique identifier of a partner address within Catena-X as defined in [CX-0010].
Position		A position within an order defines the product and the quantity the supplier has to manufacture / supply for a customer. A single order may contain multiple positions for different products.
Order		Request from a customer towards a supplier to manufacture / supply a given quantity of a specific product in a predefined time frame.
Allocated Stock		The already manufactured and not yet been used products, components or material. They are allocated to a specific customer based on the orders made by the latter and are either still in the supplier's warehouse or already in the customer's warehouse.
Provider		The party providing the Item Stock data.In the context of the Item Stock exchange this is: - the supplier for Item Stock of direction OUTBOUND - the customer for Item Stock of direction INBOUND.
Consumer		The party requesting and consuming the Item Stock data provided by the provider. In the context of the Item Stock exchange this is: - the supplier for Item Stock of direction OUTBOUND - the customer for Item Stock of direction INBOUND. Additional terminology used in this standard can be looked up in the glossary on the association homepage.
Stock Location		The physical location of a stock specified by its corresponding BPNS and BPNA. More information on BPN/S/A is provided in [CX-0010].
Customer		The recipient of products ordered from / manufactured by a supplier.
Supplier		The supplier / manufacturer of a product.
Stock		Two way direction of material on stock: - One can have a stock of material which is ready for delivery to customers - One can have a stock of material which can be used for the own production
Material		The term material is used as a catalogue item in the meaning of the Industry Core Part Type ([CX-0126]). Whenever referring to material also products, components or items are considered. Semi-finished goods are not intended to be covered.
Production Output		The output quantity in a defined period of time for a component or material.
Digital Twin	DT	Digital representation of an asset that provides data on aspects of the represented data following [CX-0002].
decentralized Digital Twin Registry	dDTR	Component providing registration and discovery API implementations following [CX-0002]. Sometimes referred to without the "decentralized" BUT in Catena-X those are always decentralized.
Asset Administration Shell	AAS	Technical concept for Digital Twins consisting of different standards. Application in Catena-X is described in Digital Twins in Catena-X standard ([CX-0002])
Shell Descriptor		Technical concept of the AAS API describing metadata of an Asset Administration Shell representing a Digital Twin. It holds identification information and metadata about which submodels are available and where to get the data from (see [CX-0002], IDTA-01002-3-0). There may exist multiple Shell Descriptor for the same represented Asset (see [CX-0126]).
Submodel Descriptor		Technical concept of the AAS API describing metadata of Submodels within a Shell Descriptor (Asset Administration Shell) (see [CX-0002], IDTA-01002-3-0).
Specific Asset Ids		Identifiers of the Shell Descriptor (Asset Administration Shell) that refer to common identification data for an asset/material at hand e.g., manufacturer part Id. Common specific asset ids used for identification are described in Industry Core Part Type Standard (see [CX-0126]).
Asset Administration Shell Identifier	AAS ID	Also referred to as Shell Descriptor ID, is the technical identifier of the Shell Descriptor.
Global Asset Id		Also referred to as Catena-X ID, is the Catena-X identifier for assets represented by Digital Twins (see [CX-0126]).
Aspect		A domain-specific view on information and functionality associated with a specific Digital Twin with a reference to a concrete Aspect Model (see [CX-0002]). Within Catena-X, an aspect is formally described using the Semantic Aspect Meta Model (see [CX-0003]).
Semantic Id		Identifier including namespace to specify the semantic description of submodels using the Semantic Aspect Meta Model (SAMM). It allows partners to know the exact data format and semantics when e.g., browsing catalogs (see [CX-0003]).
Data Space Protocol	DSP	A set of specifications designed to facilitate interoperable data sharing between entities governed by usage control and based on Web technologies. These specifications define the schemas and protocols required for entities to publish data, negotiate Agreements, and access data as part of a Dataspace. It is governed by the International Data Spaces Association. Connectors compliant to [CX-0018] support the Data Space Protocol.
Shared Asset Approach		Digital twin pattern in which each party has a twin for the same asset (Part Type). They share the same identification data in terms of specific asset ids and global asset id. The digital twins do have different technical identifiers.

Table 1: Terminology Item Stock Standard

Additional terminology used in this standard can be looked up in the glossary on the association homepage.

2 RELEVANT PARTS OF THE STANDARD FOR SPECIFIC USE CASES

This section is normative

2.1 "ITEM STOCK"

2.1.1 LIST OF STANDALONE STANDARDS

The following Catena-X standards are prerequisites for the implementation of this standard and therefore MUST be considered / implemented by the relevant parties specified in each of them.

Number	Standard	Version
[CX-0001]	EDC Discovery API	1.0.2
[CX-0002]	Digital Twins in Catena-X	2.2.0
[CX-0003]	SAMM Aspect Meta Model	1.1.0
[CX-0006]	Registration and initial onboarding	2.0.0
[CX-0010]	Business Partner Number (BPN)	2.0.0
[CX-0018]	Dataspace Connectivity	3.0.0
[CX-0126]	Industry Core Part Type	2.0.0

Table 2: List of mandatory standards

The usage of this standard may be complemented with the following Catena-X standards to further extend the range of shortage prevention possibilities:

Number	Standard	Version
[CX-0118]	Delivery Information Exchange	2.0.0
[CX-0120]	Short-term Material Demand Exchange	2.0.0
[CX-0121]	Planned Production Output Exchange	1.0.0
[CX-0145]	Days of Supply Exchange	1.0.0
[CX-0146]	Supply Chain Disruption Notifications	1.0.0

Table 3: List of non-mandatory complementary standards

2.1.2 DATA REQUIRED

No additional data requirements.

2.1.3 POLICY CONSTRAINTS FOR DATA EXCHANGE

In alignment with our commitment to data sovereignty, a specific framework governing the utilization of data within the Catena-X use cases has been outlined. As part of this data sovereignty framework, conventions for access policies, for usage policies and for the constraints contained in the policies have been specified in standard CX-0152 Policy Constraints for Data Exchange. This standard document CX-0152 MUST be followed when providing services or apps for data sharing/consuming and when sharing or consuming data in the Catena-X ecosystem. What conventions are relevant for what roles named in 1.1 AUDIENCE & SCOPE is specified in the CX-0152 standard document as well.

REMINDER OF ANTITRUST

Notice and/or acknowledgement concepts to raise awareness of antitrust issues during use of this standard are RECOMMENDED, for example through the implementation of a help desk or pop-up info.

2.1.4 DIGITAL TWINS AND SPECIFIC ASSET IDs

This standard builds upon the Industry Core Part Type [CX-0126] and the Digital Twins in Catena-X [CX-0002] standards. It follows the following design patterns:

Usage of Digital Twins as shared assets to follow a pull approach for data.
Usage of the specific asset IDs and further identification data for the Digital Twin for the Part Type (see [CX-0126]).
Provisioning of the PartTypeInformation on supplier side (see [CX-0126]).

Because both parties may provide data regarding different aspects of the same Part Type Twin, they need to use the same identification data to pinpoint it.

The supplier of the part has a Digital Twin representation and is then able to offer Item Stock data to customers.
The customer, who orders or uses the part, has a Digital Twin representation to offer Item Stock data to a supplier.
Both twins refer to the same asset and provide complementary information. They share the same identification data in two partners' context.
- The supplier
  - MUST create the Digital Twin first.
  - MUST generate the Catena-X ID and ensure that the customer-specific asset IDs and submodel descriptors are only accessible by the specific customer.
  - MAY use the Digital Twin for multiple customers.
- The customer
  - MUST create one Digital Twin per supplier.
  - MUST use the Catena-X ID generated by the supplier.

The definition of identification data (Catena-X ID, Asset Administration Shell ID, specific asset ID) MUST follow the Industry Core Part Type [CX-0126]. Refer to Chapter 4.1.2 for further details.

Note: The Part Type Twin's data is considered sensitive. Data providers MUST implement appropriate measures ensuring that competitors-specific asset IDs and/or information about submodels is accessible only to the data consumers it concerns, but not to their competitors.

Figure 2 shows how the shared asset approach is realized. The orange lines show which submodels belong to the respective AAS. All Item Stock specific submodels are bound to the specific Part Type's context e.g., meaning that the Item Stock aspect is described for the specific catalog item on supplier and customer side represented by the AASs. The orange submodels are the submodels used within this standard's context. The grey submodels are used within the Industry Core [CX-0126](PartTypeInformation, SingleLevelBomAsPlanned, SingleLevelUsageAsPlanned). The blue dashed lines show the references between DTs based on Catena-X UUIDs and BPNL information that may be resolved by the Item Relationship Service (see [CX-0126]).

Figure 2: Conceptual levels of provisioning digital twins in the shared asset approach.

Figure 2 details two conceptual levels:

The Asset level contains the asset (Industry Core Part Type) represented by a Digital Twin. The latter is provisioned as an Asset Administration Shell (AAS) within the decentralized Digital Twin Registry (dDTR) of the data provider (supplier or customer).
The Submodel level represents the actual information that are held by a Digital Twin (DT). Those submodels follow the respective definition of the in Semantic Aspect Meta Model (SAMM) format (see Chapter 3). The dDTR only holds meta-information about the Submodel (e.g. kind of submodel via semantic ID or connector endpoint information).

3 ASPECT MODELS

This section is normative

3.1 "ITEM STOCK" ASPECT MODEL

3.1.1 INTRODUCTION

This section describes the "ItemStock" semantic model used in the Catena-X network. For the complete semantics and detailed description of its properties refer to the SAMM model in Chapter 3.1.5.1.

3.1.2 SPECIFICATIONS ARTIFACTS

The modeling of the semantic model specified in this document was done in accordance to the "semantic-driven workflow" to create a submodel template specification [SMT].

This aspect model is written in SAMM 2.0.0 as a modeling language conformant to [CX-0003] as input for the semantic driven workflow.

Like all Catena-X data models, this model is available in a machine-readable format on GitHub conformant to [CX-0003].

3.1.3 LICENSE

This Catena-X data model is made available under the terms of the Creative Commons Attribution 4.0 International (CC-BY-4.0) license, which is available at Creative Commons.

3.1.4 IDENTIFIER OF SEMANTIC MODEL

The semantic model has the unique identifier

urn:samm:io.catenax.item_stock:2.0.0

This identifier MUST be used by the data provider to define the semantics of the data being transferred.

3.1.5 FORMATS OF SEMANTIC MODEL

3.1.5.1 RDF TURTLE

The RDF turtle file, an instance of the Semantic Aspect Meta Model, is the master for generating additional file formats and serializations. It can be found under the following link:

https://github.com/eclipse-tractusx/sldt-semantic-models/blob/main/io.catenax.item_stock/2.0.0/ItemStock.ttl

The open source command line tool of the Eclipse Semantic Modeling Framework is used for generation of other file formats like for example a JSON Schema, aasx for Asset Administration Shell Submodel Template or a HTML documentation.

3.1.5.2 JSON SCHEMA

A JSON Schema can be generated from the RDF Turtle file. The JSON Schema defines the Value-Only payload of the Asset Administration Shell for the API operation "GetSubmodel".

3.1.5.3 AASX

An AASX file MUST be generated from the RDF Turtle file. The AASX file defines one of the requested artifacts for a Submodel Template Specification conformant to [SMT].

4 APPLICATION PROGRAMMING INTERFACES

This section is normative

4.1 API USED TO EXCHANGE "ITEM STOCK" INFORMATION

As described in Chapter 2.1.4 this standard builds upon the [CX-0002] Digital Twins in Catena-X and [CX-0126] Industry Core Part Type standards. Therefore, the APIs provided by the Digital Twin standard are combined with the part identification defined in the Industry Core standard. This chapter defines how the aforementioned standards and the [CX-0018] standard MUST be used to facilitate the provisioning of Item Stock data. The usage of the Discovery Services defined in [CX-0001], [CX-0053] is not mandatory, because this standard assumes an already existing business relationship between the involved parties.

The sequence diagram in Figure 3 provides an overview of the interactions required to register the Part Type Twin following the shared asset approach.

Steps 1 & 2: Register the dDTR access for the partner at the connector
Steps 3 & 4: When using the repository pattern, create the submodel (and twin)
Steps 5 & 6: Register the submodel endpoint for the partner at the connector
Steps 7 & 8: Register or update the twin Shell Descriptor relying on the registered Connector asset for the submodel endpoint and the identification data of the partners.

Note: This sequence diagram is simplified and does not cover the generation of the Part Type Twin on supplier side and the handling of the identification data needed. Both partners need to create a Part Type Twin of the shared asset as well as provide Item Stock data.

Figure 3: Flow to create and register a digital twin

The sequence diagram in Figure 4 provides an overview of the interactions required when a customer (acting as data provider) provisions Item Stock data to a supplier (acting as data consumer).

The flow "Supplier reads (updated) Submodel from Customer" visualizes the sequence of calls when consuming data:

Steps 3 - 8: Contract dDTR usage in the connector.
Steps 9 - 12: Lookup the Industry Core Part Type Twin for a Part Type based on the common identification data.
Steps 13 - 18: Read the Shell Descriptor of the Industry Core Part Type Twin to extract the Item Stock submodel endpoint (registered at the connector).
Steps 19 - 24: Contract the Item Stock data usage in the connector.
Steps 25 - 29: Consume and use the Item Stock data.

Figure 4: Flow to look up a digital twin and get a submodel.

Note: Depending on the use of repository patterns and the design of the Digital Twins, the data may be updated manually in the Submodel endpoint.

4.1.1 CONNECTOR DATA ASSET STRUCTURE

The endpoints for the dDTR and the Submodel Endpoint MUST be made available BUT they MUST NOT be directly called data consumer. Rather, for access to dDTRs and Submodels, there MUST be contracts negotiated in accordance with the DSP. Therefore, the endpoints MUST be offered as connector data assets. To make these assets easily identifiable in the connector's catalog, each asset MUST be configured with a set of properties as described in the corresponding sections below.

The following table provides an overview of the connector data assets that the parties MUST offer to be able to provision and/or consume Item Stock data.

Party	REQUIRED	Asset	Purpose
Provider	Yes	"Digital Twin Registry"	Allows a consumer to query for Part Type Twins and their Item Stock submodels.
Provider	Yes	"Submodel Item Stock"	Allows a consumer to read actual Item Stock information related to a Part Type Twin.
Consumer	Yes	"Digital Twin Registry"	Allows a consumer to query for Part Type Twins and their Item Stock submodels.
Consumer	Yes	"Submodel Item Stock"	Allows a consumer to read actual Item Stock information related to a Part Type Twin.

Table 4: Connector data assets

In the sections below the asset definitions of the two different kinds of assets are defined.

CONNECTOR DATA ASSET STRUCTURE FOR "Digital Twin Registry"

To allow partners to find the "Item Stock" data for a specific Industry Core Part Type Twin, the provider MUST register a connector data asset (see details in [CX-0018]) specifying the address of the Digital Twin Registry of the provider (see [CX-0002]).

The data asset MUST be configured with the set of properties as defined in the table below.

Object	Property	Purpose	Usage & Constraints
	@id	Identifier of the asset	The asset ID MUST be unique and therefore MUST NOT be reused elsewhere.
properties	http://purl.org/dc/terms/type	Defines the "Digital Twin Registry" according to the Catena-X taxonomy.	MUST be set to `{"@id": "https://w3id.org/catenax/taxonomy#DigitalTwinRegistry"}` to allow filtering the data assets catalog for the respective "Digital Twin Registry".
properties	https://w3id.org/catenax/ontology/common#version	The version of the standard defining the implemented API of the "Digital Twin Registry"	MUST correspond to the version of the standard defining the Interfaces of the "Digital Twin Registry". The value MUST be set to `"3.0"` for "Digital Twin Registries" used by this standard.
dataAddress	@type	Type of the DataAddress node.	MUST be set to `"DataAddress"`.
dataAddress	baseUrl	Defines the HTTPS endpoint of the corresponding "Digital Twin Registry Endpoint".	The `{{ DIGITAL_TWIN_REGISTRY_ENDPOINT }}` refers to an URL under which the API of the "Digital Twin Registry" endpoint is available. HTTPS transport protocol MUST be used.
dataAddress	proxyBody	Defines whether the endpoint allows to proxy the HTTPS body	SHOULD be set to `"false"` to not allow the API endpoint to receive a HTTPS body via the HTTPS request.
dataAddress	proxyMethod	Defines whether the endpoint allows to proxy the HTTPS method	SHOULD be set to `"false"` to only allow the API endpoint to receive GET requests.
dataAddress	proxyPath	Defines whether the endpoint allows to proxy paths for the URL	MUST be set to `"true"` to allow the API endpoint to receive appended paths of the HTTPS request.
dataAddress	type	Defines the type of data plane extension handling the data exchange	MUST be set to `"HttpData"` to provide an API via an HTTPS proxy endpoint.

Table 5: Connector data assets request properties

Additionally security identification information MAY be added to secure the "Decentralized Digital Twin Registry".

When searching the Catalog of a provider, a consumer SHOULD use the following properties AND their values to identify the Data Asset specifying "Digital Twin Registry". In the connector Data Asset descriptions the API version valid for this standard is mentioned for the property https://w3id.org/catenax/ontology/common#version. The requester of a Data Asset MUST be able to handle multiple Data Asset for this endpoint, being differentiated only by the version. The requester SHOULD choose the Data Asset set with the highest compatible version number implemented by themselves. If the requester cannot find a compatible version with their own, the requester MUST terminate the data transfer.

Property	Value
http://purl.org/dc/terms/type	`{"@id": "https://w3id.org/catenax/taxonomy#DigitalTwinRegistry"}`

Table 6: Connector data assets request properties values.

An example connector data asset definition is given below.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

{
  "@context": {
    "@vocab": "https://w3id.org/edc/v0.0.1/ns/",
    "cx-common": "https://w3id.org/catenax/ontology/common#",
    "cx-taxo": "https://w3id.org/catenax/taxonomy#",
    "dct": "http://purl.org/dc/terms/"
  },
  "@id": "{{CONNECTOR_ASSET_ID}}",
  "properties": {
    "dct:type": {"@id": "cx-taxo:DigitalTwinRegistry"},
    "cx-common:version": "3.0"
  },
  "privateProperties": {
  },
  "dataAddress": {
    "@type": "DataAddress",
    "type": "HttpData",
    "baseUrl": "{{ DIGITAL_TWIN_REGISTRY_ENDPOINT }}",
    "proxyQueryParams": "true",
    "proxyBody": "false",
    "proxyPath": "true",
    "proxyMethod": "false",
  }
}

CONNECTOR DATA ASSET STRUCTURE FOR "Submodel"

To allow partners to receive the "Item Stock" data as defined in Chapter 3, the provider MUST register a connector data asset (see details in[ CX-0018]) specifying the address of the submodel endpoint (see [CX-0002]) providing the actual data.

The data asset MUST be configured with the set of properties as defined in the table below.

Object	Property	Purpose	Usage & Constraints
	@id	Identifier of the asset	The asset ID MUST be unique and therefore MUST NOT be reused elsewhere.
properties	http://purl.org/dc/terms/type	Defines the "Submodel API" according to the Catena-X taxonomy.	MUST be set to `{"@id": "https://w3id.org/catenax/taxonomy#Submodel"}` to allow filtering the data assets catalog for the respective "Submodel API".
properties	https://admin-shell.io/aas/3/0/HasSemantics/semanticId	The semantic identifier of the "Item Stock" SAMM.	MUST be set to `{"@id": "urn:samm:io.catenax.item_stock:2.0.0#ItemStock"}` to externally define how the Submodel must be interpreted. MUST NOT be set, if different submodels may be returned by this API.
properties	https://w3id.org/catenax/ontology/common#version	Version of the Submodel Interface Specification	MUST be set to `"3.0"` in accordance to [CX-0002].
dataAddress	@type	Type of the DataAddress node.	MUST be set to `"DataAddress"`.
dataAddress	baseUrl	Defines the HTTPS Submodel endpoint provisioning the Delivery Information data	The `{{ SUBMODEL_ENDPOINT }}` refers to an URL under which the Submodel API Endpoint ([CX-0002]) is available to provide the "Item Stock" . HTTPS transport protocol MUST be used.
dataAddress	proxyBody	Defines whether the endpoint allows to proxy the HTTPS body	SHOULD be set to `"false"` to not allow the API endpoint to receive a HTTPS body via the HTTPS request.
dataAddress	proxyMethod	Defines whether the endpoint allows to proxy the HTTPS method	SHOULD be set to `"false"` to only allow the API endpoint to receive GET requests.
dataAddress	proxyPath	Defines whether the endpoint allows to proxy paths for the URL	MUST be set to `"true"` to allow the API endpoint to receive appended paths of the HTTPS request. Setting this parameter depends on the implementation of the submodel lookup.
dataAddress	type	Defines the type of data plane extension handling the data exchange	MUST be set to `"HttpData"` to provide an API via an HTTPS proxy endpoint.

Table 7: Connector data assets request properties

Additionally security identification information MAY be added to secure the "Submodel API".

When searching the data assets catalog of a provider, a consumer SHOULD use the assetId previously determined via subprotocolBody of the SubmodelDescriptor's endpoint definition of subprotocol type "DSP". Refer to Chapter 4.1.2 for the definition of the subprotocolBody.

Property	Value
https://w3id.org/edc/v0.0.1/ns/id	`{{CONNECTOR_ASSET_ID}}` specified in the DSP endpoint of the SubmodelDescriptor (see Chapter 4.1.2)

Table 8: Connector data assets request properties values

An example connector data asset definition is given below.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

{
  "@context": {
    "@vocab": "https://w3id.org/edc/v0.0.1/ns/",
    "cx-common": "https://w3id.org/catenax/ontology/common#",
    "cx-taxo": "https://w3id.org/catenax/taxonomy#",
    "dct": "http://purl.org/dc/terms/",    
    "aas-semantics": "https://admin-shell.io/aas/3/0/HasSemantics/"
   },
  "@id": "{{CONNECTOR_ASSET_ID}}",
  "properties": {
    "dct:type": {"@id": "cx-taxo:Submodel"},
    "cx-common:version": "3.0",
    "aas-semantics:semanticId": {"@id":  "urn:samm:io.catenax.item_stock:2.0.0#ItemStock"}   },
  "privateProperties": {
  },
  "dataAddress": {
    "@type": "DataAddress",
    "type": "HttpData",
    "baseUrl": "{{ SUBMODEL_ENDPOINT }}",
    "proxyQueryParams": "false",
    "proxyBody": "false",
    "proxyPath": "true",
    "proxyMethod": "false",
  }
}

4.1.2 INDUSTRY CORE PART TYPE TWIN REGISTRATION AND DEFINITION

4.1.2.1 SHELL DESCRIPTOR REGISTRATION

To allow partners to receive the actual "Item Stock" data as defined in Chapter 3, the provider MUST register a Shell Descriptor in the dDTR (see [CX-0002]) so that a partner:

May lookup the Industry Core Part Type Twin based on known identification data.
May identify the connector endpoint providing access to the "Item Stock" submodel data.

The Shell Descriptors represent each an Industry Core Part Type Twin and MUST follow the rules as defined in Chapter 2.1.4.

The Shell Descriptor MUST be configured with the set of properties as defined in the table below.

Object in ShellDescriptor	Property	Purpose	Usage & Constraints
	id	Defines the technical ID of the Asset Administration Shell representing a partner's twin.	MUST be unique following Industry Core Part Type standard ([CX-0126]) and is a technical Id randomly assigned as multiple Part Type Twins may be created for one Part Type. E.g. this number differs for the twins created at supplier and customer side.
	globalAssetId	Defines the Catena-X ID of the twin.	MUST be aligned with the partner's material. When referring to the same Part Type Twin, the same number MUST be used (see [CX-0126]).
	specificAssetIds	Identifiers that may be used to lookup Part Type Twins.	MUST be set to according to the Industry Core Part Type standard ([CX-0126]). See Table 10 for respective specific asset IDs. The `"customerPartId"` MUST be set by Customers and SHOULD be set by Suppliers.
submodelDescriptor	id	Technical identifier of a SubmodelDescriptor.	MUST be set to a unique identifier.
submodelDescriptor	semanticId	The semantic identifier of the "Item Stock" SAMM.	MUST be set to `{ "type": "ExternalReference", "keys": [{ "type": "GlobalReference", "value": "urn:samm:io.catenax.item_stock:2.0.0#ItemStock" }] }` to externally define how the Submodel must be interpreted.
submodelDescriptor > endpoint	interface	Defines the Submodel Interface [CX-0002] and the version.	MUST be set to `"SUBMODEL-3.0"` to rely on current specification.
submodelDescriptor > endpoint > protocolInformation	href	Defines the direct link to the public API of the connector's data plane with a path that SHOULD be appended by the proxy, if needed.	MUST be set to the public API of the dataplane providing the data with the path appended to directly access the submodel.
submodelDescriptor > endpoint > protocolInformation	subprotocol	Defines the usage of the connector based on DSP to access and use the submodel.	MUST be set to `"DSP"` to define the connector endpoint of the subprotocol.
submodelDescriptor > endpoint > protocolInformation	subprotocolBody	Defines the asset id in the connector and the connector address to access and use the submodel.	MUST be set to `"id={{CONNECTOR_ASSET_ID}};dspEndpoint={{SUPPLIER_CONNECTOR_DSP_ENDPOINT}}"` to provide the necessary information for contracting the submodel endpoint. Refer to Chapter 4.1.2 for the definition of the asset of the subprotocolBody.

Table 9: Properties relevant for the Shell Descriptor definition

When searching the submodel in the dDTR of a provider, a consumer SHOULD use the specific asset IDs as defined in [CX-0126]. Table 10 gives an overview of the specific asset IDs that the data provider added to the ShellDescriptor so that the data consumer may find the Industry Core Part Type Twin.

Specific Asset Id	Value
digitalTwinType	"PartType". Set to identify twins compliant to the Industry Core Part Type (see [CX-0126]).
manufacturerId	Supplier / Manufacturer partner BPNL (see [CX-0010])
manufacturerPartId	Supplier / Manufacturer partner identification number of the part.
customerPartId	Customer partner identification number of the part.

Table 10: Specific asset IDs of Industry Core Part Type Twins proposed to be used to lookup a twin in the dDTR

The Shell Descriptor defines the metadata of the Industry Core Part Type Twin. The following example Shell Descriptor represents a supplier's Shell Descriptor of a supplier who provides two customers access to an "Item Stock" submodel. For further information on the creation of Part Type Twins, refer to Chapter 2.1.4.

Following [CX-0002], when searching the data assets catalog of a provider, a consumer SHOULD use the assetId determined via subprotocolBody of the SubmodelDescriptor's endpoint definition of subprotocol type "DSP" of the Submodel Descriptor of interest.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

{
  "id": "{{TECHNICAL_TWIN_ID}}",
  "globalAssetId": "{{MATERIAL_NUMBER_CX}}",
  "idShort": "Semiconductor",
  "specificAssetIds": [
    {
      "name": "digitalTwinType",
      "value": "PartType",
      "externalSubjectId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "{{SUPPLIER_BPNL}}"
          },
          {
            "type":"GlobalReference",
            "value":"{{CUSTOMER_BPNL}}"
          },
          {
             "type":"GlobalReference",
             "value":"{{OTHER_CUSTOMER_BPNL}}"
          }
          ]
      }
    },
    {
      "name": "manufacturerPartId",
      "value": "{{MATERIAL_NUMBER_SUPPLIER}}",
      "externalSubjectId": {
        "type": "ExternalReference",
        "keys": [
          {
              "type": "GlobalReference",
              "value": "{{SUPPLIER_BPNL}}"
          },
          {
              "type":"GlobalReference",
              "value":"{{CUSTOMER_BPNL}}"
          },
          {
             "type":"GlobalReference",
             "value":"{{OTHER_CUSTOMER_BPNL}}"
          }
        ]
      }
    },
    {
      "name": "manufacturerId",
      "value": "{{SUPPLIER_BPNL}}",
      "externalSubjectId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "{{SUPPLIER_BPNL}}"
          },
          {
            "type":"GlobalReference",
            "value":"{{CUSTOMER_BPNL}}"
          },
          {
            "type":"GlobalReference",
            "value":"{{OTHER_CUSTOMER_BPNL}}"
          }
        ]
      }
    },
    {
      "name": "customerPartId",
      "value": "{{MATERIAL_NUMBER_CUSTOMER}}",
      "externalSubjectId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "{{SUPPLIER_BPNL}}"
          },
          {
            "type":"GlobalReference",
            "value":"{{CUSTOMER_BPNL}}"
          }
        ]
      }
    },
    {
      "name": "customerPartId",
      "value": "{{MATERIAL_NUMBER_OTHER_CUSTOMER}}",
      "externalSubjectId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "{{SUPPLIER_BPNL}}"
          },
          {
            "type":"GlobalReference",
            "value":"{{OTHER_CUSTOMER_BPNL}}"
          }
        ]
      }
    }
  ],
  "submodelDescriptors": [
    {
      "id": "e5c96ab5-896a-482c-8761-efd74777ca97",
      "semanticId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "urn:samm:io.catenax.item_stock:2.0.0#ItemStock"
          }
        ]
      },
      "endpoints": [
        {
          "interface": "SUBMODEL-3.0",
          "protocolInformation": {
            "href": "{{SUPPLIER_CONNECTOR_DATAPLANE_PUBLIC_API}}/{{PATH_IF_NEEDED}}",
            "endpointProtocol": "HTTP",
            "endpointProtocolVersion": [
              "1.1"
            ],
            "subprotocol": "DSP",
            "subprotocolBody": "id={{CONNECTOR_ASSET_ID}};dspEndpoint={{SUPPLIER_CONNECTOR_DSP_ENDPOINT}}",
            "subprotocolBodyEncoding": "plain",
            "securityAttributes": [
              {
                "type": "NONE",
                "key": "NONE",
                "value": "NONE"
              }
            ]
          }
        }
      ]
    },
    {
      "id": "a6c96ab5-896a-482c-8761-efd74777ca99",
      "semanticId": {
        "type": "ExternalReference",
        "keys": [
          {
            "type": "GlobalReference",
            "value": "urn:samm:io.catenax.item_stock:2.0.0#ItemStock"
          }
        ]
      },
      "endpoints": [
        {
          "interface": "SUBMODEL-3.0",
          "protocolInformation": {
            "href": "{{SUPPLIER_CONNECTOR_DATAPLANE_PUBLIC_API}}/{{PATH_IF_NEEDED}}",
            "endpointProtocol": "HTTP",
            "endpointProtocolVersion": [
              "1.1"
            ],
            "subprotocol": "DSP",
            "subprotocolBody": "id={{CONNECTOR_ASSET_ID}};dspEndpoint={{SUPPLIER_CONNECTOR_DSP_ENDPOINT}}",
            "subprotocolBodyEncoding": "plain",
            "securityAttributes": [
              {
                "type": "NONE",
                "key": "NONE",
                "value": "NONE"
              }
            ]
          }
        }
      ]
    }
  ]
}

4.1.2.2 LOOKING UP A PART TYPE TWIN IN THE DDTR

To query the dDTR of a data provider, after contracting the usage via the data provider's connector (see [CX-0018]), the lookup API (see [CX-0002]) can be used relying on the specific asset IDs defined by the Industry Core Part Type (see [CX-0126]) that can be seen in Table 10 (table of shellDescriptorRegistration with specific asset IDs).

An example call relying on all information is given in the code sample below.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

GET: {{PARTNER_CONNECTOR_DATA_PLANE}}/lookup/shells?assetIds={"name":"digitalTwinType", "value": "PartType"},{"name":"manufacturerPartId", "value": "{{MATERIAL_NUMBER_SUPPLIER}}"},{"name":"manufacturerId", "value": "{{SUPPLIER_BPNL}}"},{"name":"customerPartId", "value": "{{MATERIAL_NUMBER_CUSTOMER}}"}

As a result identifiers of the ShellDescriptors will be returned. With this data, a data provider can read the ShellDescriptor to extract the endpoint data of the data provider. An example is given in the code sample below.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

GET: {{PARTNER_CONNECTOR_DATA_PLANE}}/shell-descriptors/{{AAS_IDENTIFIER}}

4.1.2.3 FETCHING SUBMODEL DATA

To fetch the Item Stock Submodel data at the submodel endpoint of a data provider, after contracting the usage via the data provider's connector (see [CX-0018]), the submodel API (see [CX-0002]) can be used.

An example call relying on all information is given in the code sample below.

Note: Expressions in double curly braces {{}} must be substituted with a corresponding value.

GET: {{HREF_PATH}}/$value

5 PROCESSES

This section is normative

5.1 GENERAL INFORMATION ON THE USE OF ITEM STOCK

A prerequisite to build up an Item Stock and allocate it to a specific customer or supplier is an existing order / call-off (build-to-order). This standard, must not be used in case of building stock without any allocation to a customer or supplier (build-to-stock).

In contrast to the Demand and Capacity Management standard [CX-0128], this information relates to short-term planning periods of 1-4 weeks. Accordingly, neither long-term planning nor strategic planning is included in the scope. This means that only the current/actual Item Stock quantities are transmitted in this standard.

We distinguish between exactly two scenarios in multi sourcing. On the one hand, the exchange of information from supplier to customer and, on the other hand, from customer to supplier. In both scenarios, information must not be shared horizontally under any circumstances. This means that the Item Stock in relation to other customers or suppliers must not be shared.

The data exchange between the C-X participants refers to the direct business relationship among each other. In the case of consignation, the warehouse is specified via the real location - the customer/supplier site. In this case the allocated stock is not considered as taken and according to our definition as not delivered (have not yet been shipped).

5.2 ITEM STOCK PROVISIONING WITHIN SINGLE SOURCING AND SINGLE CUSTOMER SCENARIOS

5.2.1 ACTORS AND ROLES

The following actors and roles occur in the described processes. The common definitions are found in Chapter 1.5. This section describes respective scenarios.

Actors	Role	Description
Customer	The customer acts as the data consumer and provider in this standard.	A business partner that procures items from its supplier and requests information about its allocated item stock information. The customer provides information about its own stock in relation to the assigned supplier.
Supplier	The supplier acts as the data consumer and provider in this standard.	A business partner that supplies items to a customer. The supplier requests the allocated item stock from the customer and provides the item stock already produced for the customer. Regardless of the site in which the item stock is located.

Table 11: Actors and roles 1

5.2.2 PROCESS REPRESENTATION

Information about the item stock is exchanged between the customer and the supplier in both directions - that means the Information is exchanged from the customer to the supplier and vice versa. The representative example explains which item stock information must be exchanged. The actual and not the planned data must be queried and transmitted. The following example shows a bottleneck situation in which the supplier has a complete loss of production for one day. This affects his ability to fulfill the demand for the next day, so he delivers only 200 pieces. Due to the given just-in-time scenario, the situation can only be partially covered by the supplier's own item stock. The exchange via item stock thus shows the consequences at an early stage and the customer can adjust its production planning.

Note: The item stock information for supplier and customer refer always to the value at the end of the business day. The supplier's production output is the value at the end of the business day and is used for delivery and stock build-up on the following day.

Recommended procedure in case of single sourcing with information about Item Stock from customer to supplier and vice versa

Note: In this example the calculations are as follows: Item Stock Customer (day n) = Item Stock Customer (day n-1) + Delivery (day n) - Consumption (day n); also: Delivery (day n) = Production Output (day n-1) - Item Stock Supplier (day n)

Table 12: Single source example

Note: In this standard, only current/actual Item Stock quantities are transmitted.

This procedure takes into consideration the following aspects:

The customer may share with the supplier the following information on a daily basis:
- Information on the volumes called off by the customer
- the supply volumes delivered in response to this call-off (covered by [CX-0118])
- the consumption allocated to the supplier's products (covered by [CX-0120])
- the actual Item Stock of its products at the customer's site (covered in this standard)
The supplier may share with the customer the following information on a daily basis:
- the supply volumes delivered in response to this call-off (covered by [CX-0118])
- the production output allocated to the customer's products (covered by [CX-0121])
- the actual Item Stock of its products at the supplier's site (covered in this standard)

5.3 ITEM STOCK PROVISIONING WITHIN MULTI SOURCING SCENARIOS

5.3.1 ACTORS AND ROLES

The following actors and roles occur in the described processes. The common definitions are found in Chapter 1.5. This section describes respective scenarios.

Actors	Role	Description
Customer	The customer acts as the data provider in this standard.	A business partner that procures items from its supplier and provides information about its own stock in relation to the assigned supplier.
Supplier A	The supplier A acts as the data consumer in this standard.	A business partner that supplies items to a customer and requests the allocated item stock from the customer. Regardless of the warehouse in which the item stock is located. Supplier A has no knowledge of the business relationship between the customer and Supplier B.
Supplier B	The supplier B acts as the data consumer in this standard.	A business partner that supplies items to a customer and requests the allocated item stock from the customer. Regardless of the site in which the item stock is located. Supplier B has no knowledge of the business relationship between the customer and Supplier A.

Table 13: Actors and roles 2

5.3.2 PROCESS REPRESENTATION

Multi-sourcing is a common scenario in the field. Suppliers usually supply several customers with the same material/component. And customers purchase the same component types from different suppliers. Because of that, in the case of multi-sourcing, when there is no possibility of differentiating the items received from different suppliers (i.e. by using different item numbers for each supplier), the customer must be aware that competition sensitive information from one supplier must not be shared with other suppliers. After evaluating different alternatives, the following procedure is the one recommended from the item stock standardization team and legal advisors to all users in order to ensure a compliant exchange of information from customer to suppliers in the case of multi-sourcing.

In this example, the shortage situation occurs at supplier B on days 5 and 6 and at supplier A on days 8 and 9. To alleviate the shortage, a larger quantity is requested from supplier A on day 5 and from supplier B on day 9. This ensures that the bottleneck situation has no effect on the customer's production.

Recommended procedure in case of multi-sourcing with information exchange from customer to supplier: quoting consumption, keeping track of deliveries

Note 1: in this example Item Stock A and Item Stock B make reference to the Item stock at the customer's site that is allocated respectively to supplier A and B.

Note 2: in this example the calculations are as follows (example on Supplier A, also applies to Supplier B): Item Stock A (day n) = Item Stock A (day n-1) + Delivery A (day n) - Allocated consumption A (day n); if Stock B (day n) ≤ 0 then Allocated consumption A (day n new) = Allocated consumption A (day n old)+ |Stock B (day n)| and Stock B (day n new)= 0

Note 3: This quote is only necessary in case keeping track of the parts supplied by different suppliers is not possible (i.e. by using different item numbers for each supplier)

Table 14: Multi-source customer example

Note: In this standard, only current/actual Item Stock quantities are transmitted.

This procedure (quoting consumption, keeping track of deliveries) takes in consideration the following aspects:

The customer may share with the supplier A the following information on a daily basis:
- Information on the volumes called off by the customer but only in relation to the specific supplier ("Allocated call off A")
- the supply volumes delivered in response to this call-off ("Delivery A") (covered by [CX-0118])
- the consumption allocated to the supplier's products ("Allocated consumption A") (covered by [CX-0120])
- the actual Item Stock at the customer ("Item Stock A"), (covered in this standard)
The customer must not share the following information with the supplier and the supplier must not be able to derive this information from the information available to it:
- Capacity data of other suppliers,
- the overall volumes called off by the customers ("Call off customer TOTAL"),
- information on the volumes called off by the customer in relation to another supplier ("Allocated call off B"),
- the supply volumes delivered by another supplier ("Delivery B"),
- the overall consumption delivered by all suppliers ("Consumption customer TOTAL"),
- the consumption allocated to another supplier ("Allocated consumption B"),
- the customer's total Item Stock ("Item stock customer TOTAL"), (covered in this standard)
- the Item Stock from another supplier at the customer ("Item Stock B"). (covered in this standard)

Note: For Supplier B, the same procedure applies in reverse.

5.4 ITEM STOCK PROVISIONING WITHIN MULTI CUSTOMER SCENARIO

5.4.1 ACTORS AND ROLES

The following actors and roles occur in the described processes. The common definitions are found in Chapter 1.5. This section describes respective scenarios.

Actors	Role	Description
Customer A	The customer acts as the data consumer in this standard.	A business partner that procures items from its supplier and requests information about the supplier's allocated item stock information.
Customer B	The customer acts as the data consumer in this standard.	A business partner that procures items from its supplier and requests information about the supplier's allocated item stock information.
Supplier	The supplier acts as the data provider in this standard.	A business partner that supplies items to more than one customer. It provides the item stock already produced for the customer. Regardless of the site in which the item stock is located.

Table 15: Actors and roles 3

5.4.2 PROCESS REPRESENTATION

In this scenario, two customers procure the same item from one supplier. In addition to the Item Stock, the call-offs and the actual delivery quantity are displayed once for each day. There is a distribution of the supplier's total production output in a ratio of 1:3, i.e. each customer receives 1/3 of the planned production quantity and 1/3 is left in the supplier's warehouse. The information transmitted must be separated for each customer. The information must not be shared horizontally under any circumstances. This means that the Item Stock in relation to other customers must not be shared. On day 5 and 6, a complete production downtime occurs at the supplier. The supplier now supplies its customers from its own stock and transmits the Item Stock information in the corresponding ratio. From day 7, production continues as planned.

Recommended procedure in case of multi customer with single sourcing

Table 16: single supplier to multi customer example

A suitable measure must be found for the allocation and provision of information. We recommend the use of the ratio or the quoting of the call-off.

Note: In this standard, only current/actual Item Stock quantities are transmitted.

This procedure takes in consideration the following aspects:

The customer may share with the supplier the following information on a daily basis:
- Information on the volumes called off by the customer
- the supply volumes delivered in response to this call-off (covered by [CX-0118])
- the consumption allocated to the supplier's products (covered by [CX-0120])
- the actual Item Stock of its products at the customer's site (covered in this standard)
The supplier may share with the customers the following information on a daily basis:
- the supply volumes delivered in response to the customer's call-off (covered by [CX-0118])
- the production output allocated to the customer's material or products (covered [CX-0121])
- the actual Item Stock of its material or products at the supplier site (covered in this standard)
The supplier must not share the following information with the customer and the customer must not otherwise be able to derive this information from the information available to it:
- Capacity and delivery data of another customer,
- the overall volumes called off by the customers,
- the supply volumes delivered to another customer,
- the supplier's total Item Stock (covered in this standard),
- the supplier Item Stock allocated for another customer (covered in this standard)

5.5 ITEM STOCK USE OF ASSIGNMENT TO SITES AND ADDRESSES

5.5.1 ACTORS AND ROLES

The following actors and roles occur in the described processes. The common definitions are found in Chapter 1.5. This section describes respective scenarios.

Actors	Role	Description
Customer	The customer acts as the data consumer and provider in this standard.	Is a business partner that procures items from its supplier and requests information about its allocated item stock information. The customer provides information about its own stock in relation to the assigned supplier.
Supplier	The supplier acts as the data consumer and provider in this standard.	Is a business partner that supplies items to a customer. It requests the allocated item stock from the customer and provides the item stock already produced for the customer. Regardless of the site in which the item stock is located.

Table 17: Actors and roles 4

5.5.2 PROCESS REPRESENTATION

The distinction between customer and supplier locations must be made via the unique breakdown to BPNS and BPNA. This means that a legal entity can have several sites and addresses with its BPNL and these are mapped via the BPNS and BPNA. Why is this distinction used? A location is always assigned to the customer and supplier via the site with its BPNS. However, a site can have several addresses, e.g. for delivery. Furthermore, additional addresses can belong to a site via consignation and external warehouses. It is therefore also possible that, for example, the customer address is the same as the address of the external warehouse which is assigned to the supplier. In addition, the delivery information may also be enriched in this way, because a delivery time results from the respective location with its address.

6 REFERENCES

6.1 NORMATIVE REFERENCES

Number	Standard	Version
[CX-0001]	EDC Discovery API	1.0.2
[CX-0002]	Digital Twins in Catena-X	2.2.0
[CX-0003]	SAMM Aspect Meta Model	1.1.0
[CX-0006]	Registration and initial onboarding	2.0.0
[CX-0010]	Business Partner Number (BPN)	2.0.0
[CX-0018]	Dataspace Connectivity	3.0.0
[CX-0053]	Discovery Finder and BPN Discovery Service APIs	1.1.0
[CX-0118]	Delivery Information Exchange	2.0.0
[CX-0120]	Short-term Material Demand Exchange	2.0.0
[CX-0121]	Planned Production Output Exchange	2.0.0
[CX-0126]	Industry Core Part Type	2.0.0
[CX-0128]	Demand and Capacity Management	2.0.0
[CX-0145]	Days of Supply Exchange	1.0.0
[CX-0146]	Supply Chain Disruption Notifications	1.0.0
[CX-0152]	Policy Constraints For Data Exchange	1.0.0

6.2 NON-NORMATIVE REFERENCES

This section is non-normative

Context	Link
[CX-OMW]	Catena-X Operating Model
[RFC2119]	Bradner, S. Key words for use in RFCs to Indicate Requirement Levels. Available online: https://datatracker.ietf.org/doc/html/rfc2119
[RFC8174]	Leiba, B. Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words. Available online: https://datatracker.ietf.org/doc/html/rfc8174
[SMT]	How to create a submodel template specification. Guideline. Download from: https://industrialdigitaltwin.org/wp-content/uploads/2022/12/I40-IDTA-WS-Process-How-to-write-a-SMT-FINAL-.pdf
[IDTA-01002-3-0]	Specification of the Asset Administration Shell Part 2: Application Programming Interfaces. Download from: https://industrialdigitaltwin.org/wp-content/uploads/2023/04/IDTA-01002-3-0_SpecificationAssetAdministrationShell_Part2_API.pdf

6.3 REFERENCE IMPLEMENTATIONS

This section is non-normative

Not applicable.

ABSTRACT​

FOR WHOM IS THE STANDARD DESIGNED​

COMPARISON WITH THE PREVIOUS VERSION OF THE STANDARD​

1 INTRODUCTION​

1.1 AUDIENCE & SCOPE​

1.2 CONTEXT AND ARCHITECTURE FIT​

1.3 CONFORMANCE AND PROOF OF CONFORMITY​

1.4 EXAMPLES​

1.5 TERMINOLOGY​

2 RELEVANT PARTS OF THE STANDARD FOR SPECIFIC USE CASES​

2.1 "ITEM STOCK"​

2.1.1 LIST OF STANDALONE STANDARDS​

2.1.2 DATA REQUIRED​

2.1.3 POLICY CONSTRAINTS FOR DATA EXCHANGE​

REMINDER OF ANTITRUST​

3.1.1 INTRODUCTION​

3.1.2 SPECIFICATIONS ARTIFACTS​

3.1.3 LICENSE​

3.1.4 IDENTIFIER OF SEMANTIC MODEL​

3.1.5 FORMATS OF SEMANTIC MODEL​

3.1.5.1 RDF TURTLE​

3.1.5.2 JSON SCHEMA​

3.1.5.3 AASX​

4 APPLICATION PROGRAMMING INTERFACES​

4.1 APIAPI An API is a way for two or more computer programs to communicate with each other. USED TO EXCHANGE "ITEM STOCK" INFORMATION​

4.1.1 CONNECTOR DATA ASSETAsset On the Data Provider side, an Asset describes the data set which will be shared or can be consumed by a Data Consumer. STRUCTURE​

CONNECTOR DATA ASSETAsset On the Data Provider side, an Asset describes the data set which will be shared or can be consumed by a Data Consumer. STRUCTURE FOR "Digital Twin Registry"​

CONNECTOR DATA ASSETAsset On the Data Provider side, an Asset describes the data set which will be shared or can be consumed by a Data Consumer. STRUCTURE FOR "Submodel"​

4.1.2 INDUSTRY CORE PART TYPE TWIN REGISTRATION AND DEFINITION​

4.1.2.1 SHELL DESCRIPTOR REGISTRATION​

4.1.2.2 LOOKING UP A PART TYPE TWIN IN THE DDTR​

4.1.2.3 FETCHING SUBMODEL DATA​

5 PROCESSES​

5.1 GENERAL INFORMATION ON THE USE OF ITEM STOCK​

5.2 ITEM STOCK PROVISIONING WITHIN SINGLE SOURCING AND SINGLE CUSTOMERCustomer In the context of OSim, the receiver of produced goods from a supplier. SCENARIOS​

5.2.1 ACTORS AND ROLES​

5.2.2 PROCESS REPRESENTATION​

Recommended procedure in case of single sourcing with information about Item Stock from customerCustomer In the context of OSim, the receiver of produced goods from a supplier. to supplierSupplier In the context of OSim, the producer of goods. and vice versa​

5.3 ITEM STOCK PROVISIONING WITHIN MULTI SOURCING SCENARIOS​

5.3.1 ACTORS AND ROLES​

5.3.2 PROCESS REPRESENTATION​

Recommended procedure in case of multi-sourcing with information exchange from customerCustomer In the context of OSim, the receiver of produced goods from a supplier. to supplierSupplier In the context of OSim, the producer of goods.: quoting consumption, keeping track of deliveries​

5.4 ITEM STOCK PROVISIONING WITHIN MULTI CUSTOMERCustomer In the context of OSim, the receiver of produced goods from a supplier. SCENARIO​

5.4.1 ACTORS AND ROLES​

5.4.2 PROCESS REPRESENTATION​

Recommended procedure in case of multi customerCustomer In the context of OSim, the receiver of produced goods from a supplier. with single sourcing​

5.5 ITEM STOCK USE OF ASSIGNMENT TO SITES AND ADDRESSES​

5.5.1 ACTORS AND ROLES​

5.5.2 PROCESS REPRESENTATION​

6 REFERENCES​

6.1 NORMATIVE REFERENCES​

6.2 NON-NORMATIVE REFERENCES​

6.3 REFERENCE IMPLEMENTATIONS​

Legal​

ABSTRACT

FOR WHOM IS THE STANDARD DESIGNED

COMPARISON WITH THE PREVIOUS VERSION OF THE STANDARD

1 INTRODUCTION

1.1 AUDIENCE & SCOPE

1.2 CONTEXT AND ARCHITECTURE FIT

1.3 CONFORMANCE AND PROOF OF CONFORMITY

1.4 EXAMPLES

1.5 TERMINOLOGY

2 RELEVANT PARTS OF THE STANDARD FOR SPECIFIC USE CASES

2.1 "ITEM STOCK"

2.1.1 LIST OF STANDALONE STANDARDS

2.1.2 DATA REQUIRED

2.1.3 POLICY CONSTRAINTS FOR DATA EXCHANGE

REMINDER OF ANTITRUST

3.1.1 INTRODUCTION

3.1.2 SPECIFICATIONS ARTIFACTS

3.1.3 LICENSE

3.1.4 IDENTIFIER OF SEMANTIC MODEL

3.1.5 FORMATS OF SEMANTIC MODEL

3.1.5.1 RDF TURTLE

3.1.5.2 JSON SCHEMA

3.1.5.3 AASX

4 APPLICATION PROGRAMMING INTERFACES

4.1 API USED TO EXCHANGE "ITEM STOCK" INFORMATION

4.1.1 CONNECTOR DATA ASSET STRUCTURE

CONNECTOR DATA ASSET STRUCTURE FOR "Digital Twin Registry"

CONNECTOR DATA ASSET STRUCTURE FOR "Submodel"

4.1.2 INDUSTRY CORE PART TYPE TWIN REGISTRATION AND DEFINITION

4.1.2.1 SHELL DESCRIPTOR REGISTRATION

4.1.2.2 LOOKING UP A PART TYPE TWIN IN THE DDTR

4.1.2.3 FETCHING SUBMODEL DATA

5 PROCESSES

5.1 GENERAL INFORMATION ON THE USE OF ITEM STOCK

5.2 ITEM STOCK PROVISIONING WITHIN SINGLE SOURCING AND SINGLE CUSTOMER SCENARIOS

5.2.1 ACTORS AND ROLES

5.2.2 PROCESS REPRESENTATION

Recommended procedure in case of single sourcing with information about Item Stock from customer to supplier and vice versa

5.3 ITEM STOCK PROVISIONING WITHIN MULTI SOURCING SCENARIOS

5.3.1 ACTORS AND ROLES

5.3.2 PROCESS REPRESENTATION

Recommended procedure in case of multi-sourcing with information exchange from customer to supplier: quoting consumption, keeping track of deliveries

5.4 ITEM STOCK PROVISIONING WITHIN MULTI CUSTOMER SCENARIO

5.4.1 ACTORS AND ROLES

5.4.2 PROCESS REPRESENTATION

Recommended procedure in case of multi customer with single sourcing

5.5 ITEM STOCK USE OF ASSIGNMENT TO SITES AND ADDRESSES

5.5.1 ACTORS AND ROLES

5.5.2 PROCESS REPRESENTATION

6 REFERENCES

6.1 NORMATIVE REFERENCES

6.2 NON-NORMATIVE REFERENCES

6.3 REFERENCE IMPLEMENTATIONS

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