Data Distribution Management Service Research Articles

Parallel Data Distribution Management on Shared-memory Multiprocessors

The problem of identifying intersections between two sets of d -dimensional axis-parallel rectangles appears frequently in the context of agent-based simulation studies. For this reason, the High Level Architecture (HLA) specification—a standard framework for interoperability among simulators—includes a Data Distribution Management (DDM) service whose responsibility is to report all intersections between a set of subscription and update regions. The algorithms at the core of the DDM service are CPU-intensive, and could greatly benefit from the large computing power of modern multi-core processors. In this article, we propose two parallel solutions to the DDM problem that can operate effectively on shared-memory multiprocessors. The first solution is based on a data structure (the interval tree) that allows concurrent computation of intersections between subscription and update regions. The second solution is based on a novel parallel extension of the Sort Based Matching algorithm, whose sequential version is considered among the most efficient solutions to the DDM problem. Extensive experimental evaluation of the proposed algorithms confirm their effectiveness on taking advantage of multiple execution units in a shared-memory architecture.

Interest Manager for Networked Driving Simulation Based on High-Level Architecture

In networked driving simulation, two or more human drivers participate interactively within a shared virtual environment. Thereby, typical applications of driving simulation can be extended to consider multi-driver scenarios, where a much closer approximation of reality with its unpredictability is achieved. However, the utilized network is typically prone to a considerable amount of message traffic. In addition to restricted system scalability, the resulting degradation of network performance leads to invalid simulation outcomes or unacceptable system behavior. High-Level Architecture (HLA) is the IEEE standard 1516 that provides specific guidelines for networked simulation. Data distribution management (DDM) is one of the service groups provided by the HLA standard. The aim of the DDM service is to reduce network traffic and to save effort required to process unnecessary received data. However, existing approaches for current DDM implementations show major drawbacks in terms of utilization complexity, inefficiency, and yet added network overhead. This paper presents a new concept of an interest manager that takes over the DDM functionality and avoids these drawbacks. Simulation data is exchanged between the participating driving simulators only when it is necessary according to the driving situations. The interest manager was implemented and its efficient functionality was validated by analyzing the network load of two driving maneuvers with and without the interest manager.

Parallel Framework for HLA Federate Oriented to Simulation Component on Multicore Platform

提出了一种面向仿真组件的并行联邦成员框架,以解决基于HLA(high level architecture)复杂仿真系统联邦成员开发的问题,并提升多核处理器环境下联邦成员的运行性能.并行联邦成员框架通过仿真组件的组合、装配来构建联邦成员.通过仿真引擎管理、数据分发管理、对象管理、组件管理服务和负载平衡功能,并行联邦成员框架为仿真模型构建了一个多核的并行执行环境,并确保并行成员能与RTI 正确交互.通过实验来研究并行成员框架引入的额外开销,并比较并行成员和普通成员的性能.实验结果表明,并行框架能够充分利用多核处理器的计算能力来减少仿真系统运行时间,提高系统性能.;A simulation component, oriented as a parallel framework for federate, was raised to facilitate federate development and improve execution performance of federate on multicore platform. Simulation components were employed to compose and assemble federates in parallel framework. With simulation engine management service, data distribution management service, object management service, component management service and load balancing of parallel framework, a multicore parallel environment was provided for simulation component, which also assured correct interactions between parallel federates and RTI. Experiments were carried out on the extra overhead introduced by parallel framework and performance comparisons between normal federate and parallel federate were made. Results showed that parallel framework fully exploited multicore processors with reduced execution time and improved performance of simulation system.

High Level Architecture Data Distribution Management migration from DoD 1.3 to IEEE 1516

AbstractThe High Level Architecture (HLA) is an infrastructure for assembling federations of distributed simulations, or federates, that interoperate by exchanging simulation data at run time. HLA's Data Distribution Management (DDM) services control the amount of simulation data delivered to an HLA federate by establishing dynamic data communications connections based on the federates' run‐time declarations of data production and requirements. In September 2000 the Institute for Electrical and Electronic Engineers (IEEE) approved a new standard for HLA, the IEEE 1516 standard. Most parts of the IEEE 1516 standard are generally similar to the U.S. Department of Defense HLA standard upon which it was based, the DoD 1.3 standard. However, the DDM services were significantly changed in the IEEE 1516 standard. The changes to DDM included the removal of routing spaces and the introduction of default dimension ranges. These changes simplified the implementation of some approaches to using DDM, but they did not affect the fundamental functionality of DDM. With some care, HLA users can develop DDM usage approaches that can be migrated smoothly from DoD 1.3 to IEEE 1516. Copyright © 2004 John Wiley & Sons, Ltd.