The Use of GERAM to Provide Context for Heterogeneous Infrastructure Technology in a Given Enterprise

Use of GERAM to Provide a Unifying Representation of

Heterogeneous Information Infrastructure Standards

A Whitepaper Prepared for the Strategic Workshop on Enterprise Integration and Enterprise Computing, Brisbane Australia, November 19 - 20, 1998

Neil Christopher

National Institute of Standards and Technology

Gaithersburg, Maryland USA

Statement of the Problem

Current approaches for coordinating and specifying the interrelationships between information infrastructure standards development activities are inadequate. Each new information infrastructure technology development creates the potential for a corresponding standards activity. Unfortunately the products of standards development activities rarely provide sufficient specification of their intended or expected technical relationships with other standards products.

Standards liaison activities are intended to fulfill the standards coordination function but they often do not result in either meaningful coordination or in the explicit representation of the contextual relationships between the standards. In standards development, as in business, a complex set of conditions must be favorable to the interaction between the organizations for coordination efforts to be successful. Empirical evidence suggests that the world-wide network of standards liaison activity is insufficient to wring inefficiencies out of global information technology standards development processes.

Even if liaison activities were completely successful in harmonizing standards development activities the standards consumer is never given a comprehensive view of standards that may be combined to produce their Type 1 systems. Most manufacturing firms do not have the ability to participate broadly in these activities to the degree suggested by their business interests. These standards consumers face the daunting task of trying to sort through standards documents to determine the context and intended usage of the information infrastructure specifications. Instead of attempting to understand the complex landscape of standards these consumers often take matters into their own hands by forming industry coalitions that attempt to rapidly develop consensus about a limited set of immediately useful emerging technologies.

The industry led efforts are often very focused and rarely specify how they fit into this landscape. Industry coalition members focus on implementation rather than promulgation and standards development professionals rarely have intimate access to coalition efforts. These circumstances further exacerbate problems associated with broad understanding of the context, scope, and relationships between information infrastructure standards. The standards development community has the responsibility to solve these problems.

Background

The National Institute of Standards and Technology participates in the development of formal standards for enterprise representation, information models, information infrastructures, control architectures, as well as in industry consortia developing domain specific Type-1 architecture specifications. Within NIST, the Manufacturing Engineering Laboratory Manufacturing Systems Integration Division, has the mission to participate in the development of enterprise-wide information technologies, standards, and services that support the needs of the manufacturing community.

It its support of enterprise integration standards, the Manufacturing Systems Integration Division (MSID) is the home of the ISO TC184 SC5 WG1 convenorship and liaison with the IFIP/IFAC Enterprise Integration Task Force. MSID maintains the ISO TC 184 SC4 secretariat and participates actively in the development of ISO 10303 STEP. MSID was instrumental in establishing the Object Management Group’s Manufacturing Domain Task Force (MfgDTF). MSID co-chairs the MfgDTF Enterprise Resource Planning (ERP) Working Group, the Manufacturing Execution System Machine Control (MES/MC) Working Group, and the Product Data Management (PDM) Revision Task Force. MSID staff members act as liaison between the MfgDTF ERP Working Group and the Open Applications Group (OAG) industry consortia. They act as liaison between the MfgDTF MES/MC Working Group and the ISO TC184 SC4 WG8 (MANDATE). They participate in the development of the Knowledge Interchange Format (KIF) and they launched the development of the Process Specification Language (PSL). They are members of the Supply Chain Council (SCC), CommerceNet, and RosettaNet. MSID’s sister organization, the Intelligent Systems Division, has developed the Intelligent Systems Architecture Model as a follow on activity to the Real-time Control Systems (RCS) Architecture and the Enhanced Machine Controller (EMC) development.

In 1996 the "Joint Standards Workshop for the Use of Models That Define the Data and Processes of Information Systems," (Joint Workshop) was held in Bellevue, Washington USA. The participants in this workshop represented NIST, ISO TC184 SC4, ISO TC184 SC5, JTC1, IEC, IFIP/IFAC, and others involved in enterprise integration related standards development activities. The Joint Workshop produced a series of resolutions intended to elicit standards harmonization. These resolutions addressed the Sharing and Reuse of Standards for Modeling as well as Managing Duplication of Standards for Modeling. In 1997 the International Conference on Enterprise Integration Modeling and Technology (ICEIMT97) brought together researchers, industry representatives, and standards development professionals to address enterprise integration modeling problems but the follow-on projects identified at the conference have been slow to develop.

In spite of its large commitment of resources MSID and other similar organizations participating in enterprise-wide standards development activities have not sufficiently articulated the complex relationships between enterprise integration related standards. In order to address this problem MSID is proposing a project to use Generalized Enterprise Reference Architecture Model (GERAM), developed by the IFIP/IFAC Taskforce on Enterprise Integration, to represent the context and relationships between these standards.

Analysis

MSID proposes the use of GERAM to provide a common, unifying representation of the information infrastructure technology standards to which MSID contributes. However, it is not clear that GERAM can be used to represent the complex interrelationships and context between standards to the degree that standards development professionals and information technology systems integration professionals will find substantially beneficial. GERAM, at a minimum provides the most comprehensive classification of enterprise elements. The various specifications under development should all be able to be represented in GERAM but it is not clear that they could all be represented in the same instance of GERAM. If they can be represented in the same instance of GERAM what mechanism does GERAM provide to represent the relationships between the standards?

The point of view assumed in the work will have a critical impact on the representation. The project could adopt the perspective that MSID is the enterprise to be represented and the standards under development are the products of the enterprise. Alternatively, the project could adopt the perspective that the standards products are all partial specifications of some theoretical enterprise information infrastructure.

From the perspective of the enterprise components specified by GERAM, it is likely that all of MSID’s standards and technology development efforts could be represented. For example, the Process Specification Language (PSL) is clearly an Enterprise Modeling Language (EML). The Intelligent Systems Reference Architecture (ISAM) can be classified as a Particular Enterprise Model (EM) and a software instance of ISAM, e.g. the Enhanced Machine Controller (EMC) can be classified as an Enterprise Module (EMO). However, it is not clear whether the Common Object Request Broker Architecture (CORBA) should be classified in its entirety as an EM or whether it should be represented as a set of individual EM’s. Further, it is not clear how one would use GERAM to represent the relationship between CORBA and ISAM. These are only a few of the many questions that will have to be answered in order to represent the set of standards of immediate interest to MSID.

MSID will initially attempt to answer some of these questions by using GERAM to represent the scope, context, and relationships between a subset of its work in the development of CORBA and ISAM. If this proof of concept effort produces beneficial results then the work could be extended to include representation of the work of ISO TC184 SC4. Ultimately, MSID would like to have a densely populated model, publicly available, collaboratively developed, and operated over its own life cycle. It is likely that the use of GERAM, populated with information infrastructure standards could be useful to broad audience and that it could provide a context for the coordination work performed by standards technical liaisons.