BOMs – Base Object Models

1. BOMs – Base Object Models Björn Löfstrand Manager M&S Services, Pitch Technologies Arkitekturdag 3, FMV, Stockholm, December 2006

2. BOM Definition • Piece-part approach to Modeling • Conceptual Models • With focus on Simulation • Information Exchange Data Models • With focus on Federated Systems based on HLA • Provides linkage from conceptual elements to constructs for information exchange in a federated system BOM A piece part of a conceptual model, simulation objectmodel, or federation object model, which can be used as a building block in the development and/or extension of a simulation or federation SISO-STD-003-2006

3. Basic Concept Simulation Conceptual Model (Representation of relevant “stuff” in the “real world” at a level of description necessary to achieve the goals of the system) • How to find the right levels of description is an art not covered by BOMs. • Some aspects of a conceptual model can be captured in a BOM and used as a building-block for conceptual modeling • BOMs can provide a link between conceptual elemetns such as entities, actions and events to information exchange constructs (e.g. HLA FOM). Federation of Distributed Systems/Simulation (Federates with the collective responsibility of modeling the elements defined in the conceptual model) • Model responsibility is allocated to federates and they collaborate through the use of a common Networked Information Infrastructure (e.g. HLA RTI) • BOMs can be used to document Information Exchange Data Models (e.g. HLA FOM)

4. Background • Simulation Conceptual Model • Specification of types of entities, attributes, relations, behavior and actions relevant to be represented in the simulation • Independent of how the responsibility of modeling these concepts is allocated to different components (federates) in a federated system (federation) • HLA Object Model Template • A template specification for documenting HLA Federation and Simulation Object Models (FOMs and SOMs) representing the information exchange data model (IEDM) • Represents the type of information needed to be exchange during simulation in order to correctly represent the simulation conceptual model • Federation Development and Execution Process (FEDEP) • Guidance for developing HLA Federations • Recognizes Reference Models and Base Object Models as important approaches to developing FOMs and SOMs

5. Federation Development and Execution Process Perform Conceptual Analysis Plan, Integrate, and Test Federation Define Federation Objectives Analyze Data and Evaluate Results Develop Federation Design Federation Execute Federation and Prepare Outputs 1 2 3 4 5 6 7 Behavior Actions Conceptual Entities Patterns of Interplay Simulation Conceptual Model FederationObject Model (FOM) Allocation of Model Responsibilities FEDEP IEEE 1516.3-2000 Recommended Practice

6. BOM History 2004 1996 1998 1999 2000 2001 2002 2003 2005 2006 HLAEvolved ReferenceFOM Study Group BOM Study Group FEDEP PDG SCM SISO-STD-003-2006 BOM RPR FOM BOM PN BOM Methodology Strawman BOMPDG / DG FOM“piece parts” (FEDEP, OMT) SRML HLA IEEE 1516

7. BOM Rationale • Interoperability • Common understanding on how information is exchanged and interpreted is key in achieving interoperability • BOMs provide a way of documenting not only HLA mechanisms or constructs for information exchange, but also the pattern of interplay that is supported by the exchange. • Reuse • The BOM concept is based on the assumption that piece-parts of simulations and federations can be extracted and reused as modeling building-blocks or components. • The interplay interface between conceptual entities within a simulation can be captured and characterized in the form of reusable patterns. • Composability • The implementation of a pattern of interplay using HLA object model constructs is captured in the BOM and can be used to compose Federation Object Model (FOM) • The patterns of interplay can be used to compose Conceptual Models

8. BOMs can capture some aspects of the Simulation Conceptual Model The BOM template is not a Conceptual Model Representation Standard References to other Conceptual Model using other types of Representations is allowed Primarily used to capture key patterns of interplay between entities in the conceptual model Provides patterns of interplay as building-blocks when constructing new Simulation Conceptual Models BOM and Conceptual Models Conceptual Model Pattern Of Interplay State Machine Entity Type Event Type Weapons Effect states pattern actions Pattern of Interplay State Machines

9. BOMs can capture how information is shared among federates using interactions and attribute updates of simulated entities The BOM template is not a Federation Agreement Representation Standard The BOM standard is strongly influenced by HLA but not a required target architecture Based on IEEE1516-2007 (HLA Evolved) OMT format Primarily used to capture reusable pieces of OMT information to be used as building-blocks when constructing new FOMs and SOMs. Opportunity for standardizing common BOMs and for making existing Reference FOMs (e.g. RPR-FOM) BOM based. BOMs and HLA Object Models Object Model Definition HLA Object Classes HLA Object Classes HLA Object Class Attributes HLA Interaction Classes HLA Interaction Classes HLA Interaction Class Parameters HLA Data Types Weapons Effect HLAInteractionsand Attribute Updates Federate Federate Federation Information Exchange Data Model (IEDM) Federation Object Model (FOM)

10. BOMs provides a mechanism to map aspects of the Simulation Conceptual Model to Information Exchange constructs Allows a simple way of identifying FOM elements when allocating the responsibility of modeling aspects of the Simulation Conceptual Model to different federates Pattern Actions (Messages and Triggers) are mapped to HLA Interactions and/or Attribute Updates) BOM Model Mapping Conceptual Model Pattern Of Interplay State Machine Entity Type Event Type Model Mapping Entity Type Mapping Event Type Mapping Object Model Definition HLA Object Classes HLA Object Classes HLA Object Class Attributes HLA Interaction Classes HLA Interaction Classes HLA Interaction Class Parameters HLA Data Types Essential metadata needed so thatthe BOM can be described, discovered and properly reused Model Identification (Metadata) Notes and definitionssupporting any of theabove mentionedelements Notes Lexicon (definitions)

11. Example Simulation Conceptual Model Real-world entities, processes and other phenomenon to be represented in a simulation Identified Patterns of Interplay Restaurant visit - Arrival - Ordering - Payment

12. Payment Pattern (Conceptual Model) Customer Entity Type Waiter Entity Type Payment Actions Ready Ready Customer Request Check Prepare Bill Wait for Bill Waiter States Check Brought To Table Customer States Ready Pay Customer Pays Wait for change Process Bill ReceiptChangeReturned Leave restaurant Ready

13. Federation Design (FEDEP step 3) Allocation of Model Responsibilities Waiter Customer RTI The Payment Interplay between the Waiter and Customer needsto be modeled in the distributed simulation. Payment Event Types and supporting Entity Type characteristics needsto be reflected between federates. Use the Payment BOM to find out how to exchange this information using HLA.

14. Basic Concept Conceptual Model BOMs Federation Patterns of Interplay, EntityTypes and EventsTypes Mapping of CM to HLA OM FOM BOM supports the development of HLA federations by linking patterns of interplayin the conceptual model to HLA constructs for information exchange between federates

15. BOM XML Format

16. Current BOM activities ? • BOM Product Support Group (PSG) • offer continuity and a place for developers and users of the standards to ask questions, request explanations, seek support, or register change requests for subsequent versions of the product. • www.sisostds.org

17. Questions http://www.boms.info BOM Drafting Group (DG)

18. BACKUP SLIDES

19. Payment Pattern Description Table

20. Payment Entity & Event Types Entity Type Table Event Type Table

21. Waiter Payment States State Machine Table

22. Model Mapping CM to HLA Entity Type Mapping Table Event Type Mapping Table