RFC 1667 (rfc1667) - Page 2 of 7

Modeling and Simulation Requirements for IPng

RFC 1667     Modeling and Simulation Requirements for IPng   August 1994


   This paper is intended to serve as input to the IPng design effort by
   specifying the network-layer requirements of Defense Modeling and
   Simulation (M&S) applications. It is important that the M&S community
   make its unique requirements clear to IPng designers so that
   mechanisms for meeting these requirements can be considered as
   standard features for IPng. The intention is to make IPng's benefits
   of wide COTS availability, multi-vendor interoperability, and cost-
   effectiveness fully available to the M&S community.

2.  Background: Overview of Distributed Interactive Simulation

   The Defense Modeling and Simulation community requires an integrated,
   wide-area, wideband internetwork to perform Distributed Interactive
   Simulation (DIS) exercises among remote, dissimilar simulation
   devices located at worldwide sites. The network topology used in
   current M&S exercises is typically that of a high-speed cross-country
   and trans-oceanic backbone running between wideband packet switches,
   with tail circuits running from these packet switches to various
   nearby sites. At any given site involved in an exercise, there may be
   several internetworked local area networks on which numerous
   simulation entity hosts are running.  Some of these hosts may be
   executing computer-generated semi-automated forces, while others may
   be manned simulators.  The entire system must accommodate delays and
   delay variance compatible with human interaction times in order to
   preserve an accurate order of events and provide a realistic combat
   simulation. While the sites themselves may be geographically distant
   from one another, the simulation entities running at different sites
   may themselves be operating and interacting as though they are in
   close proximity to one another in the battlefield.  Our goal is that
   all of this can take place in a common network that supports all
   Defense modeling and simulation needs, and hopefully is also shared
   with other Defense applications.

   In a typical DIS exercise, distributed simulators exchange
   information over an internetwork in the form of standardized protocol
   data units (PDUs). The DIS protocols and PDU formats are currently
   under development.  The first generation has been standardized as
   IEEE 1278.1 and used for small exercises (around 100 hosts), and
   development of a second generation is underway.  The current
   Communications Architecture for DIS specifies use of Internet
   protocols.

   The amount, type, and sensitivity level of information that must be
   exchanged during a typical DIS exercise drives the communications
   requirements for that exercise, and depends on the number and type of
   participating entities and the nature and level of interaction among
   those entities.  Future DIS exercises now in planning extend to
   hundreds of sites and tens of thousands of simulation platforms



Symington, Wood & Pullen