In simulation, run-time infrastructure (RTI) is a middleware that is required when implementing the High Level Architecture. RTI is the fundamental component of HLA. It provides a set of software services that are necessary to support federates to coordinate their operations and data exchange during a runtime execution. In other sense, it is the implementation of the HLA interface specification but is not itself part of specification. Modern RTI implementations conform to the IEEE 1516 and/or HLA 1.3 API specifications. These specifications do not include a network protocol for RTI. It is up to the implementors of an RTI to create a specification. Due to this, interoperability between RTI products and often, RTI versions, should not be assumed unless the vendor specifies interoperability with other products or versions.

[edit] Known implementations
| Commercial |
| Name |
Vendor |
Standard |
Bindings |
License |
| CAE RTI |
CAE Inc. |
1.3, IEEE 1516 |
C++, |
Commercial |
| Chronos RTI |
Magnetar Games |
IEEE 1516 |
C++, .NET |
Commercial |
| MÄK High Performance RTI |
MÄK Technologies |
1.3, IEEE 1516-2000, IEEE 1516-2010 (HLA Evolved) |
C++, Java |
Commercial |
| HLA Direct |
General Dynamics C4 Systems |
1.3 |
? |
Commercial |
| SimWare RTI |
Nextel Aerospace Defence & Security S.L. |
1.3, IEEE 1516-2000 |
C++ |
Commercial |
| Openskies RTI |
Cybernet Systems |
1.3, IEEE 1516 |
C++ |
Commercial |
| Pitch pRTI |
Pitch Technologies |
1.3, IEEE 1516-2000, IEEE 1516-2010 (HLA Evolved) |
C++, Java |
Commercial |
| Mitsubishi ERTI |
Mitsubishi Electric Corp. and Mitsubishi Space Software Co. Ltd |
1.3 |
C++ |
Commercial |
| RTI NG Pro |
Raytheon Virtual Technology Corporation |
1.3, IEEE 1516 |
C++, Java |
Commercial |
| Non-commercial |
| Name |
Vendor |
Standard |
Bindings |
License |
| BH-RTI |
Beijing University of Aeronautics and Astronautics Virtual Reality Laboratory |
1.3, IEEE 1516 |
? |
? |
| MATREX RTI |
Dynamic Animation Systems |
1.3, IEEE 1516 |
C++, Java |
US Government |
| CERTI |
ONERA |
1.3partial, IEEE 1516 partial |
C++, Matlab, Fortran90, Python, Java |
GPL, LGPL |
| EODiSP HLA |
P&P Software |
IEEE 1516partial |
Java |
GPL |
| GERTICO (German RTI based on Corba) |
Fraunhofer IOSB |
1.3, IEEE 1516 |
C++ |
Bundeswehr |
| The Portico Project(formerly jaRTI) |
littlebluefrog labs |
1.3, IEEE 1516 |
Java, C++ |
CDDL |
| Open HLA |
|
1.3, IEEE 1516-2000, IEEE 1516-2010 (HLA Evolved) |
Java |
Apache License |
| RTI-S |
US JFCOM J9 Directorate |
1.3 partial |
C++, Java |
US Government |
| Rendezvous RTI (formerly known as Reusable Architecture for Interoperable Universal Simulations Project # 94) |
National University of Sciences and Technology (NUST), Pakistan |
1.3 |
C++, Java |
NUST |
| Discontinued |
| Name |
Vendor |
Standard |
Bindings |
License |
| GMU RTI |
George Mason University |
1.1 |
C++ |
Free software license |
| jaRTI |
littlebluefrog labs |
1.3 partial, IEEE 1516 partial |
Java, C++ |
CDDL |
| RTI NG |
DMSO |
1.3 |
C++, Java |
|
| SXTA |
|
IEEE 1516 |
C# |
BSD license |
| XRTI (Extensible Run-Time Infrastructure) |
Naval Postgraduate School |
IEEE 1516 |
C++ |
BSD license |
| yaRTI (yet another RTI) |
|
1.3 |
C++, Ada |
GPL |