﻿
##################################################################################################################

RPR (pronounced 'reaper') FOM – Real-time Platform-level Reference Federation Object Model
--------------------------------------------------------------------------------------------------

While the HLA Standards dictate how federates exchange data, it is a FOM (Federation Object Model)
that dictates what data is being exchanged in a particular federation. HLA does not mandate the
use of any particular FOM, however, several "reference FOMs" have been developed to promote a-priori
interoperability. That is, in order to communicate, a set of federates must agree on a common
FOM (among other things), and reference FOMs provide ready-made FOMs that are supported by a wide
variety of tools and federates. Reference FOMs can be used as-is, or can be extended to add new
simulation concepts that are specific to a particular federation or simulation domain.

The RPR FOM (Real-time Platform-level Reference FOM) is a reference FOM that defines HLA classes,
attributes and parameters that are appropriate for real-time, platform-level simulations. Applications
that have previously used DIS (or would have considered using DIS), often use the RPR FOM
(or a derivative of it) when they play in an HLA world. The RPR FOM was developed by a Simulation
Interoperability Standards Organization (SISO) Product Development Group (PDG). Its goal was not to
just implement the DIS PDU structures within HLA object and interaction classes, but rather to provide
an intelligent translation of the concepts used in DIS to an HLA environment.

RPR FOM 1.0 became a SISO Standard in 1999, under the name SISO-STD-001.1-1999. A companion document,
known as the GRIM (Guidance, Rationale, and Interoperability Mappings) provides documentation for
the RPR FOM. This document is known as SISO-STD-001-1999.

RPR FOM 1.0 is based on the IEEE 1278.1-1995 version of the DIS Standard. RPR FOM 2.0, based on
the IEEE 1278.1a-1998 addendum is nearing approval as a SISO Standard.

Source: VT MAK website (http://www.mak.com/support/resources/industry-standards/378-rpr-fom-real-time-platform-level-reference-federation-object-model)

##################################################################################################################

Common HLA terminology
----------------------

Federate: an HLA compliant simulation entity.

Federation: multiple simulation entities connected via the RTI using a common OMT.

Object: a collection of related data sent between simulations.

Attribute: data field of an object.

Interaction: event sent between simulation entities.

Parameter: data field of an interaction

Source: Wikipedia

##################################################################################################################

File Formats
------------

BOM : Base Object Model

OMT : Object Model Template - provides the common framework for object interaction documentation and interoperability

FOM : Federation Object Model - described in several different files at different levels of detail
  FED : Federation Execution Data - subset of FOM
  OMD :
  OMT : Object Model Template - specifies what information is communicated between simulations

MOM: Management Object Model

Source: Modeling, Design and Evaluation of Networking Systems and Protocols through Simulation
        Dissertation by Daniel J. Lacks, Fall 2007




