Day 3: Modeling and ERP Reference Architectures

Transcription

1 Day 3: Modeling and ERP Reference Architectures CIS Department Professor Duane Truex III

2 Air Force Mentor-Protégé Enterprise Reference Architectures Ronald E. Giachetti, Ph.D. Associate Professor Industrial and Systems Engineering Florida International University Duane P. Truex, Ph.D. Associate Professor Robinson College of Business Department of Computer Information Systems Georgia State University ERP Methodology and Project Management

3 Everything should be made as simple as possible, but not simpler Albert Einstein

4 Modeling Theory Agenda Reference Architectures ARIS Reference Architecture as a commercial example utilized by SAP

5 Definitions Enterprise: a complex set of business processes that can be designed to accomplish a specific set of objectives. Architecture: " A description (often graphical) of the structure of something. " A structured plan, a framework on the basis of which a product or an organization of an enterprise can be constructed Reference model: a general model that can be used as a base to derive other models from. Reference Architecture: is a structured set of models which represent the building blocks of the system.

6 FLORIDA Air Force INTERNATIONAL Mentor-Protégé UNIVERSITY Why we need ERP Reference Architectures ERP systems are complex and difficult to understand how they operate. A reference architecture is a model that describes ERP systems helps people understand how they work. Use of reference architectures for: " Business Process Reengineering (both AS-IS and TO-BE modeling) " Training " Configuration Reference architectures capture, standardize, and represent the commonalities found in business process reengineering and enterprise integration projects (Vernadat 1996). Characterize the best-in-class management practices and software solutions; i.e. knowledge management. Inclusion of all elements. Leverage the previous work done in enterprise engineering; i.e., learning.

7 Models An abstract representation of reality that excludes much of the world s infinite detail. The purpose of a model is to reduce the complexity of understanding or interacting with a phenomenon by eliminating the detail that does not influence its relevant behavior.

8 Abstraction

9 Modeling Point #1 Modeling is the art of abstraction, knowing what to include in model and what to leave out.

10 A model reveals what its creator believes is important in understanding or predicting the phenomena modeled

11 Mecator s Projection But Africa is more than 10 times larger than Greenland!

12 Peterson s Projection: Area Accurate

13 Modeling Point #2 All models are built with a purpose, the purpose is determined by the model creator. Standard models have built in purposes (for example, UML activity diagrams or role activity diagrams).

14 Model Views A Figure 1. Front view of physical object

15 Model Views Possibility 1 Possibility 2 A A Figure 2. Two possible top views for the same front view

16 Enterprise System Views CIMOSA ARIS Zachman Curtis Function Information Organization Resource Control Data Function Organization Data Process I/O Function Behavior Organization or resource information

17 Enterprise Views A Reference Architecture for an ERP system requires the following views: " Information or Data view describes the data structure of the entities or objects in the system. " Function View describes the functions supported by the system (what the system does). " Process View describes how the system completes the functions. " Organization View describes how the enterprise is organized.

18 Modeling Point #3 Systems tend to be complex, our models only abstract limited parts of the entire system (called a view). You need multiple views to understand the entire system. We use decomposition, but instead of a hierarchy into views. Views must be consistent!

19 Enterprise Modeling Enterprise modeling has to fulfill several requirements to achieve efficient and effective enterprise integration: " provide a modeling language easily understood by non-it professionals, but sufficient for modeling complex industrial environments. " provide a modeling framework which: covers the life cycle of enterprise operation from requirements definition to end of life. enables focus on different aspects of enterprise operation by hiding those parts of the model not relevant for the particular point of view. supports re-usability of models or model parts

20 ARIS The Architecture for Information Systems (ARIS) developed in Germany and adopted by SAP. Adheres to enterprise concepts found in CIMOSA, GRAI, and other RA. Uses Event Process Chains to model processes.

21 ARIS Materials mgmt Executive mgmt Sales Organizational view Disposition Inventory Offer Request Request received Sales processing Customer Request Request processing Request processed Offer processing Sales Request processing Check Credit worthiness Determine delivery date Offer processing Data view Control view Functional view

22 Event Process Chains Event Driven Process Chains (EPC), which are one of the central components of the Architecture for Integrated Information Systems (ARIS) (Scheer 1995). Used by SAP in modeling business processes supported by their ERP package SAP R/3. EPC depict several important relationships in a business process. " Control Flow depicted as a sequence of eventfunction-event linkages. " Information flow which specifies where data is created, read, updated, or deleted by a function. " Organization assignment showing who does the function.

23 CASE Tool based on EPC

24 Function Link Operators Process Path Organization Unit Information Object An event describes a change of state in the system. A function describes the transformation from an entry state to a target state. The link operators describe the logical connection between events and functions or process paths. A process path describes the link to another process. An organization unit describ who is responsible for completing the function. An information object describes a real - world data structure (e.g. order form) Information Flow An information flow describes either the creation, read, update, or deletion of t Control Flow The control flow connects Assignment of Organization Unit information object. events and functions to show the sequence of activities. The organization unit assignment shows who he es FLORIDA Air Force INTERNATIONAL Mentor-Protégé UNIVERSITY EPC Constructs Construct Symbol Definition Event Event name Function name V XOR V Process Name Organization unit name Information object name

25 EPC for Latin American PrePaid Telephone Cards START V Sales Information Sales Analysis (2,2,3) Generate Supply Request : D Generate Inventory Report : D Inventory Report (2,4,4) Supply Request Sent (4,5) Supply Request (1,4,5) Review Supply Request : S XOR Supply Request Accepted Inventory Report Generated Supply Request Rejected (5,7) V V (2,3) (1,1,3) Supply Request (1,3,5) Generate PIN Order : S Generate PO :M V PO PO Sent POS PIN Order Generated PIN Order Generated V (3,5) PIN Order (2,3) Generate Order Details/ (1,3,5) Request Prototype : M (3,5) Order Details (1,5,6) Prototype Requested Order Details CD-ROM with PINs Create CD- ROM with PINs : PM (1,3,5) (4,5) Generate Prototype Card : P (1,4,5) (1,3,5) CD-ROM with PINs created (3,5) Prototype Card Ready (5,7) Prototype Card for Validation (1,5,6) (5,6) V Validate Prototype Card : M (1,5,6) Printing Order (1,4,6) Print Cards : P (5,6) Prototype Card Validated V Order Details PO (4,6) (1,5,6) Activation/ Deactivaion Printing Order Generated Generate Printing Order : M (1,3,5) Printing Order

26 Summary Reference Architectures describe how an ERP system is organized and operates. SAP makes the greatest usage of reference architectures, but other vendors use them as well. The reference architecture is used to configure, understand, and drive process redesign efforts.