Data Distribution Service (DDS) which shares many of the same characteristics but having an open on-the-wire protocol for system interoperability. Criticism HLA is a Message-oriented middleware that defines as a set of services, provided by a C++ or Java API. There is no standardized on-the-wire protocol. Participants in a federation must use RTI libraries from the same provider and usually also of the same version, which in some cases is perceived as a drawback. Most current tools also provide interconnectivity through sockets. External links The HLA Tutorial: a free tutorial (PDF) See also List of commercial and non-commercial RTIs Computer simulation Distributed computing Simulation Interoperability Standards Organization References External links Errata to IEEE Standard for Modeling and Simulation (M&S) High Level Architecture (HLA) — Federate Interface Specification Department of Defense (DoD) Interpretations of the IEEE 1516–2000 series of standards, Release 2 (2003-jul-01) IEEE standards Distributed computing architecture Military simulation Simulation software