Working Draft 1 UCM Reference Architecture 2 1.0 Draft 3 Authors 4 5 Scott Hinkelman Contributors 6 7 8 9 10 11 12 2009-03-20 Jim Wilson Nikola Stojanovic Mark Crawford Pat O’Conner Michael Rowell David Connelly Last Edited: 03 April 2009 13 UN/CEFACT Context Methodology (UCM) Technical Specification Copyright © UN/CEFACT 2007-2009. All Rights Reserved. Page 1 of 5 Working Draft 14 15 16 17 18 19 20 21 2009-03-20 Introduction The UN/CEFACT Unified Context Methodology (UCM) is a methodology for defining precise information semantics based on information context. While there are, and will continue to be various approaches to defining semantics, the UN/CEFACT UCM approach requires shared knowledge – there is no intention for dynamic understanding of among information producers and consumers. That is, while UCM provides a method to organize and define context values and their relationships to business information, such values and relationships must be known in advance by the users. This may be achieved through shared or copied context-value libraries. 24 UCM consists of three foundational dimensions, which frame its intended use. These three dimensions provide the foundation of the UCM Reference Architecture and reflect input from a variety of use cases submitted to the UCM project from various stakeholders. 25 Foundational Dimensions 26 The three dimensions are: 22 23 27 1. Modeling Dimension 28 2. Syntax-Binding Dimension 29 3. Deployment Dimension 30 31 32 33 34 Modeling Dimension The modeling dimension addresses the definition, management, and governance of business concepts. The following diagram illustrates the modeling dimension’s basic workflow concepts as applied to CCTS information modeling: Modeling Dimension UCM Iterative CC / BIE / BP Refinement Semantic Based Modeling Type/ValueDomain Modeling CC / CDT Libraries Context Values, Classification Schemes, Context Libraries BIE / BDT / BP Libraries BIEs / BDTs / BPs Contextualized Profile 35 36 37 ~ ~ Central to the modeling dimension are the complementary activities of semantic-modeling and type/value-domain modeling. While both are intrinsic to the modeling dimension, they differ in UN/CEFACT Context Methodology (UCM) Technical Specification Copyright © UN/CEFACT 2007-2009. All Rights Reserved. Page 2 of 5 Working Draft 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 respect to the effect on related business concepts, and are therefore distinct activities within this dimension. Semantic modeling is the essence of the CCTS component model pattern of specialization by restriction, where a business concept (a Core Component, or CC) is defined without any specified business context. Context-specific entities (Business Information Entities, or BIEs) are then defined based on a CC by selecting a set of basic and complex properties of an ACC and associating the ABIE within an instance of a classification scheme. Semantics are realized in UCM by classification schemes which narrow the CC business concept by associating a BIEs with specific context values. The realization of meaning for a specific BIE is a function of the precision of the context values defined in the instance of a context classification scheme where a given BIE is classified and the specific contextual category where BIE was classified. It is important to understand that UCM does not specify contextual classification categories and values – but how categories and values are specified, including their relationships to one another in context classification scheme instances. This differs from CCTS 2.01 specifications, which specifies context categories and how to assign their values. (UCM plans to provide examples based on the CCTS 2.01 categories in order to demonstrate how UCM can be used to support those classification categories.) Type/value-domain modeling defines possible types and allowed value ranges. Unlike semanticmodeling , type/value-domain modeling usually does not increase the precision of meaning of a given business concept (a CC). UCM therefore distinguishes type/value-domain modeling from semantic modeling. The two modeling activities form an iterative process of refinement. Within this process, CC and CDT (Core Data Type) Library aspects must be accessed and leveraged, providing lifecycle and management of these context independent entities. Libraries of BIEs and BDT (Business Data Type classified in instances of context classification schemes, which define classification values, are also directly accessible aspects from the semantic modeling process. The Modeling dimension’s output is a BIE/BDT Contextualized Profile. This profile is the result of interrogation, or query, of the CC/CDT libraries, context values of classification scheme instances classifying BIEs, and context libraries for a given business-usage context. Such interrogation is accomplished by leveraging part, or all, classification schemes and component libraries available within the modeling environment. The BIE/BDT Contextualized Profile represents the semantic content input to the Syntax-Binding Dimension. The modeling dimension primarily addresses business information concerns. Applicable UCM specifications include: Context Classification Schemes – models defining how to define classification scheme instances and the relationships of classification values for classifying BIEs and/or references to them. Tooling APIs for context-aware modeling to facilitate consistent software tooling products. 73 74 75 76 2009-03-20 UN/CEFACT Context Methodology (UCM) Technical Specification Copyright © UN/CEFACT 2007-2009. All Rights Reserved. Page 3 of 5 Working Draft 77 78 2009-03-20 BIE reference specifications to permit efficient classification and transmission of classification scheme instances of large amounts BIEs. 79 Syntax-Binding Dimension 80 Syntax-binding transforms the BIE/BDT contextualized profile to a specific syntax. 81 The following diagram illustrates basic syntax-binding concepts: 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 UCM’s syntax-binding dimension produces a contextualized syntax-specific payload structure reflective of the BIE/BDT contextual profile. A Syntax-Specific Contextual Model Payload reflects classification, library, and BIE/BDT artifacts defined during modeling. This propogates the semantics through a machine-processable syntax-specific payload definition. For example, an XML Schema could be used as the model, and could be generated to reflect the Context Classification Scheme instances containing Context Values and associations with the included BIEs. The best use of the specific syntax (such as XML) will influence the naming and design rules that determine this exact structure. Further, it is possible that such structure can be designed to use referencing (“by-reference”) or passing actual content (“by-content”) of either the actual BIE business information and/or the Context Scheme instance containing the Context Values. The BIE/BDT vocabulary expressed in the syntax-specific payload model has precise meaning to the extent of, quality and granularity of the discipline used in the Modeling Dimension. Payload structure representing context reflection will differ per syntax, depending on best usage of the specific syntax restrictions and its capabilities. Syntax Binding is driven by Naming and Design Rules (NDR) for a specific syntax which defines representation of the business concepts, classification schemes, and payload structure utilizing the capabilities of the syntax. The ultimate output of the Syntax Binding Dimension is a Syntax-Specific Contextual Model Payload. This is a ‘model’ in the sense, that it defines a payload structure of definitions (not instances) of BIE/BDT. The Syntax Binding Dimension of UCM is fundamentally a representation dimension concerning technology, but also payload layout using specific technologies. Appropriate UCM specifications in this area are: UN/CEFACT Context Methodology (UCM) Technical Specification Copyright © UN/CEFACT 2007-2009. All Rights Reserved. Page 4 of 5 Working Draft 106 107 2009-03-20 The representation of BIEs and BDT models and relationship to their based-on Core Components. 110 Payload design for representing a structure of BIE and BDT models and how they are organized within the payload structure concerning referencing or relating to their classification schemes, component libraries, etc. 111 Deployment Dimension 108 109 114 Deployment is focused on specific instances of the Syntax-Specific Contextual Model Payloads that would reflect the context in which the interchange of information between two endpoints occurs. 115 The following diagram illustrates the basic concepts of the deployment dimension: 112 113 116 117 118 119 120 121 122 123 124 125 126 127 While the Syntax-Specific Contextual Model Payload is a context-aware payload structure of BIE/BDT models (or definitions), the Contextual Instance Payload which is output from the Deployment dimension is a single instance of the model (ie, “message on the wire”). Creation of the Contextual Instance Payload is driven by the metadata and operational requirements for a specific run-time business situation. The dynamics of the deployed operating environment may differ across the usages of the same Syntax-Specific Contextual Model Payload. Examples would be local languages, local code lists, restrictions with specific business partner database fields, etc. The Contextual Instance Payload is produced considering such business dynamics by including all information needed for a comprehensive business context across all dimensions of modeling, syntax representation, and deployment. 129 The Contextual Instance Payload is a specific structure, which is appropriate for containment within business messages and/or business message envelopes. 130 Applicable UCM specifications include: 128 131 132 133 134 135 Business Partner specifications which identify restrictions on a per partner basis. Language or dialect rules which identify specific languages to be used at runtime Code list usage rules which identify specific lists of codes appropriate for a given location, etc. Interchange mechanism for aligning understanding of Contextual Schemes used between business partners UN/CEFACT Context Methodology (UCM) Technical Specification Copyright © UN/CEFACT 2007-2009. All Rights Reserved. Page 5 of 5