Distributed Interactive Simulation (DIS) is a standard for conducting real-time platform-level wargaming across multiple host computers. The standard was developed over a series of "DIS Workshops" at the Interactive Networked Simulation for Training symposium, held by the University of Central Florida's Institute for Simulation and Training (IST). At the time, IST was contracted by the United States Defense Advanced Research Project Agency to undertake research in support of the US Army Simulator Network (SIMNET) program. Funding and research interest for DIS standards development decreased following the proposal and promulgation of its successor, the High Level Architecture (HLA, initially entitled DIS++), in 1996.

There was a NATO standardisation agreement (STANAG 4482, Standardised Information Technology Protocols for Distributed Interactive Simulation (DIS), adopted in 1995) on DIS for modelling and simulation interoperability, but this was also abandoned in favour of HLA as early as 1998. The first draft HLA STANAG ran afoul of administrative procedures when it changed sponsors within NATO, which forced the process to start all over again at square one —which is why the HLA STANAG (4603) is still at the draft stage.

DIS is defined under IEEE Standard 1278:

• IEEE 1278-1993 - Standard for Distributed Interactive Simulation - Application protocols
• IEEE 1278.1-1995 - Standard for Distributed Interactive Simulation - Application protocols
• IEEE 1278.1-1995 - Standard for Distributed Interactive Simulation - Application protocols - Errata (May 1998)
• IEEE 1278.1A-1998 - Standard for Distributed Interactive Simulation - Application protocols
• IEEE-1278.2-1995 - Standard for Distributed Interactive Simulation - Communication Services and Profiles
• IEEE 1278.3-1996 - Recommended Practice for Distributed Interactive Simulation - Exercise Management and Feedback
• IEEE 1278.4-1997 - Recommended Practice for Distributed Interactive - Verification Validation & Accreditation
• IEEE 1278.5-XXXX - Fidelity Description Requirements (never published)

In addition to the IEEE standards, the Simulation and Interoperability Standards Organization (SISO) maintains and publishes an enumerations and bit encoded fields document yearly. This document is referenced to by the IEEE standards.

Application protocol

Simulation state information is encoded in formatted messages, known as Protocol Data Units (PDUs) and exchanged between hosts using existing transport layer protocols, though normally broadcast User Datagram Protocol is used. There are several versions of the DIS application protocol, not only including the formal standards, but also drafts submitted during the standards balloting process.

• Version 1 - Standard for Distributed Interactive Simulation - Application Protocols, Version 1.0 Draft (1992)
• Version 2 - IEEE 1278-1993
• Version 3 - Standard for Distributed Interactive Simulation - Application Protocols, Version 2.0 Third Draft (May 1993)
• Version 4 - Standard for Distributed Interactive Simulation - Application Protocols, Version 2.0 Fourth Draft (March 1994)
• Version 5 - IEEE 1278.1-1995
• Version 6 - IEEE 1278.1-1995 and IEEE 1278.1A-1998

Protocol data units

The current version of the DIS application protocol defines 67 different PDU types, arranged into 12 families. Frequently used PDU types are listed below for each family.

• Entity information/interaction family - Entity State, Collision
• Warfare family - Fire, Detonation
• Logistics family
• Simulation management family - Start/Resume, Stop/Freeze, Acknowledge
• Distributed emission regeneration family - Designator, Electromagnetic Emission, IFF/ATC/NAVAIDS, Underwater Acoustic
• Radio communications family - Transmitter, Signal
• Entity management family
• Minefield family
• Synthetic environment family
• Simulation management with reliability family
• Live entity family
• Non-real time family

See also

• Computer simulation
• DIS Data Dictionary