High Level Architecture Runtime Infrastructure Research Articles

A distributed simulation framework for modeling cyber attacks and the evaluation of security measures

The aim of this work is to propose a framework for the distributed simulation of cyber attacks based on high-level architecture (HLA), which is a commonly used standard for distributed simulations. The proposed framework and the corresponding simulator, which is called the distributed cyber attack simulator (abbreviated by DCAS), help administrators to model and evaluate the security measures of the networks. At the core of the DCAS is a simulation engine based on Portico, which is an open source HLA run-time infrastructure. The DCAS works in two modes: interactive and automated. Three types of simulation components (which are called federates in HLA terminology) are considered in the framework: the (1) network federate, (2) attacker federate and (3) defender federate. The simulator provides features for graphical design of the network models, animated traffic simulation, data collection, statistical analysis and different consoles for attacking and defending elements (e.g., intrusion detection systems, intrusion prevention systems). To increase the fidelity of the simulation outputs, real-world payloads are used by the DCAS. All the exploits information and the parameters of various network elements are automatically extracted from the open source vulnerability database. Also, the Snort rule-set is used as the signature database of the defending elements. The architecture and algorithms of the DCAS and the corresponding underlying simulation engine plus the security evaluation results of two illustrative examples are presented in this paper.

A virtual environment for complex products collaborative assembly operation simulation

As complex products such as automobiles and ships are usually developed at geographically dispersed locations, it brings the difficulty for component model verification and assembly process evaluation. To cope with this challenge, a relatively comprehensive system scheme which supports complex product real-time collaborative interactive assembly is proposed. To get high performance, the technologies such as parallel rendering for complex scene based on pc-cluster, high-efficient collision detection method, the mechanism of event synchronization based on HLA/RTI (High level Architecture/Run-time Infrastructure) are applied. A prototype system named Distributed Parallel Virtual Assembly Environment (DPVAE) is developed. With DPVAE, users at different location can do assembly operation collaboratively by hand or by tool, to conduct the component model verification and assembly process evaluation at the same time. Through a case study of RA750 car assembly, the validity of system functions has been demonstrated successfully.

Damage and protection simulation system of military engineering based on high level architecture

To satisfy the needs of damage analysis,protection evaluation,and protection training in military engineering,a simulation structure about damage and protection problems of military engineering,based on High Level Architecture/Run Time Infrastructure (HLA/RTI),was put forward. On the foundation of simulation conceptual design,simulation frame and logic function structure were designed and developed with the aim at component reusability and extensibility based on HLA theory. For model problem is the core problem in HLA federal development,simulation model system in damage and protective fields for military engineering was established,and model was designed,in following the model frame of the military training information system. Finally,federal workflow was given,and federal members' behavior design with UML sequence diagram,following federal time strategy.

Applications of HLA on Platform of Complex Product’s Cooperative Design & Simulation

Take “Research on minitype universal autonomous docking mechanism” as an example, the paper studied on the platform of complex product’s cooperative design and simulation of mechanical field. The process of mechanical component design was introduced. The paper put forward the bottleneck problem in the design process of data transmission and gave the solution. A new method that uses HLA/RTI (High Level Architecture/Runtime Infrastructure) for function module communication was given. By using component technology and integrating all the function module of current commercial software based on the design process, this platform expands easily and the simulation sub-system can plug and play.

An Agent Infrastructure over HLA for Distributed Simulation of Reconfigurable Systems and its Application to UAV Coordination*

This paper proposes an agent infrastructure (Theatre) centered on Java for distributed simulations over High-Level Architecture/RunTime Infrastructure (HLA/RTI). The architecture rests on actors (agents) as the basic building blocks. Actors have a public message interface and encapsulate a state of local variables and a behavior patterned as a finite state machine. Actors interact with one another by asynchronous message passing. At the system level, theatres are used as the execution platforms for actors. Theatres naturally map on to HLA federates. Actors can migrate between theatres for load-balancing concerns, or in response to (re)configuration operations of dynamic structure systems. The paper introduces Theatre and demonstrates its application to a complex simulation model based on unmanned aerial vehicles (UAVs). The case study is an open agent-based distributed model where mobile agents follow communication patterns established at runtime.

Shared State Synchronization for HLA-Based Distributed Simulation

The problem of shared state is well known to the parallel and distributed simulation research community. In this article, the authors revisit the problem of shared state in the context of a High Level Architecture (HLA)-based distributed simulation. A middleware approach is proposed to solve this problem within the framework of the HLA runtime infrastructure. Four solutions to this problem are implemented in the middleware using receive-order messages. The authors discuss the implementation issues of these four solutions in the middleware. Experimental results comparing the performance of these four solutions against a simple request-reply approach using timestamp-order messages are also presented.

Scalability and Performance Evaluation of DDM-Based Aggregation/Dissaggregation Protocols for Large-Scale Distributed Interactive Simulations Systems

Aggregation/disaggregation is a method for implementing multi-resolution simulations within a High Level Architecture (HLA) federation. HLA is a U.S. Department of Defense (DoD) developed standard to facilitate linking different types of simulations, in various locations, to form an or interactive, full-scale simulation, called a federation. Data Distribution Management (DDM) is a High Level Architecture/Run-time Infrastructure (HLA/RTI) service that manages the distribution of state updates and interaction information and controls the volume of data exchanged, in large-scale distributed simulations. The purpose of HLA is to promote interoperability and reuse among heterogenous simulations, including those simulations that offer varied levels of resolution, to provide practical training to military personnel of different ranks. The purpose of Aggregation/disaggregation is to ensure consistency in state updates between federates simulating objects at various levels of resolution. This paper focuses on the scalability of aggregation/disaggregation with different DDM implementations and examines the effects, on performance of large-scale simulations. We implement a federate-based aggregation/disaggregation scheme, originally introduced in [TAN01], with a tank dogfight scenario, aggregating five tanks into one tank battalion and disaggregating the battalion back into five individual entities (tanks). The DDM methods we analyze consist of the Fixed Grid-Based method, the Dynamic Grid-Based method and the Region-Based method. In [TAN01], testing of this federate-based aggregation/disaggregation was limited to a dual federation and a single DDM scheme. In an effort to determine the scalability of aggregation/disaggregation, with three methods of DDM, we measure the communication overhead and analyze performance during a federation execution. We present the results of extensive testing, varying the number of aggregation/disaggregation requests, the number of multi-resolution federates participating in the federation, the number of objects, the number/size of the grids and report on the performance evlauation of our protocols using an extensive set of simulation experiments.

Integrating water quality models in the High Level Architecture (HLA) environment

Abstract. HLA (High Level Architecture) is a computer architecture for constructing distributed simulations. It facilitates interoperability among different simulations and simulation types and promotes reuse of simulation software modules. The core of the HLA is the Run-Time Infrastructure (RTI) that provides services to start and stop a simulation execution, to transfer data between interoperating simulations, to control the amount and routing of data that is passed, and to co-ordinate the passage of simulated time among the simulations. The authors are not aware of any HLA applications in the field of water resources management. The development of such a system is underway at the UFZ -Centre for Environmental Research, Germany, in which the simulations of a hydrodynamic model (DYNHYD), eutrophication model (EUTRO) and sediment and micro-pollutant transport model (TOXI) are interlinked and co-ordinated by the HLA RTI environment. This configuration enables extensions such as (i) "cross-model" uncertainty analysis with Monte Carlo Analysis: time synchronisation allows EUTRO and TOXI simulations to be made after each successive simulation time step in DYNHYD, (ii) information transfer from EUTRO to TOXI to compute organic carbon fractions of particulate matter in TOXI, (iii) information transfer from TOXI to EUTRO to compute extinction coefficients in EUTRO and (iv) feedback from water quality simulations to the hydrodynamic modeling.

Multimedia communication over HLA/RTI

This paper presents a generic solution for multimedia communication based on simplified Real-time Transport Protocol (RTP) over High level architecture/Run-time Infrastructure (HLA/RTI) in distributed simulation environment. It can support bilateral/multilateral multimedia transmission for high volume audio, video, image and text data. The multimedia communication FOM/SOM is designed and a multimedia communication prototype system is constructed. Experiments show that the scheme can meet the requirements for real-time transmission and high communication efficiency. Multimedia communication has already been applied in an HLA-compliant complex distributed simulation system.

An Approach for the Unified Time Management Mechanism for HLA

The High Level Architecture (HLA) is the IEEE 1516 standard to model and design a distributive simulation environment. It establishes a common distributed simulation framework, which facilitates the interoperability and reuse of simulation components. However, some HLA services are very low level and difficult to use, especially when a simulation is designed with a particular time synchronization mechanism. This article describes an agent interface, called Smart Time Management (STM). The capabilities of the STM include the following: taking over the event’s time-stamp tagging work, maintaining a lookahead value, and unifying different time advance approaches provided by the HLA runtime infrastructure. In addition, it adopts the time warp mechanism for optimistic simulation. In conclusion, the STM presents a unified and scalable middle layer to allow the user to construct an HLA federation with a unanimous Time Management interface when solving the synchronization issue.

Performance evaluation of Data Distribution Management strategies

AbstractData Distribution Management (DDM) is a High Level Architecture/Run‐Time Infrastructure (HLA/RTI) service that manages the distribution of state updates and interaction information in large‐scale distributed simulations and limits and controls the volume of data exchanged during the simulation.In this paper, we describe a mini‐RTI framework that we have developed in an effort to determine the most efficient model for applying the DDM service and the limitations of the scalability of various DDM methods. We study and compare the performance of the following five DDM strategies: two variations of the fixed‐based method, two variations of the dynamics grid‐based scheme and the region‐based method. Due to a lack of accepted benchmarks, we also propose a variety of workloads and scenarios, which we hope will become a standards benchmark within the distributed simulation communities. Copyright © 2004 John Wiley & Sons, Ltd.

Smart Time Management—the unified time synchronization interface for the distributed simulation

Distributed simulation is a widely studied technique for the networked virtual environment. Among existing technologies, High Level Architecture (HLA) establishes a common distributed simulation framework that facilitates the interoperability and reuse of simulation components. However, some HLA services are very low-level and difficult to use, especially when a simulation is designed using a particular time synchronization mechanism. This paper describes an agent interface called Smart Time Management (STM). STM is used to unify the time management services of the time-stepped, event-driven, and optimistic time advancement in HLA specification. The capabilities of the STM include the followings: taking over events timestamp tagging work, maintaining a look-ahead value, and unifying different time advance approaches provided by the HLA Run Time Infrastructure (RTI). In addition, it adopts the time warp mechanism for optimistic simulation. In summary, STM presents a unified and scalable middle layer to allow the user to construct an HLA federation with a unanimous time management interface when solving the synchronization issue. The presented middle layer enables the user to deploy the conservative and optimistic synchronization mechanisms in a unanimous way.

分散通信ミドルウェアＨＬＡ／ＲＴＩの宇宙機シミュレーションヘの適用性評価

We have been developing a spacecraft simulation environment based on object-oriented design. The system consists of models of the hardware components, numerical solvers such as for dynamics and thermal conditions, the simulation framework to control the modules, and a simulation environment including a DB and GUI. The system enables distributed simulations for distributed parallel developments between the core bus system modules and the mission system modules, or distributing the CPU load. Moreover, it can verify on-board models (on-board software, hardware-in-the-loop). We examined a distributed computing middleware, High-Level Architecture/Run-Time Infra­structure (HLA/RTI) to evaluate the functions and the performance in spacecraft simulations. HLA/RTI was proposed by Defense Modeling and Simulation Office (DMSO), USA, and approved as an open standard of distributed simulation as IEEE Standard 1516 in September 2000. The performance of two types of RTI that depend on a volume of data to transmit/receive and a number of distributed modules was observed in different network environments. The two types were applied to a simplified H-IIA Transfer Vehicle (HTV) simulator to study the feasibility.

Supporting large-scale distributed simulation using HLA

This article describes the design of a Web-based environment to support large-scale distributed simulation using Java and IEEE standard P1516 high level architecture (HLA) framework and rules. Based on the run-time infrastructure (RTI) services within the HLA and Java application programmer's interfaces (APIs) of the RTI, the proposed HLA-based environment provides an architectural foundation to enhance interactivity, portability, and interoperability for Web-based simulations. In addition, the proposed architectural design not only provides a client/server mechanism for simulation on the Web, but also supports a distributed federation execution over the network. A 3-level control mechanism (3LCM) was implemented to HLA-based middleware federateServer, in order to adaptively maintain information consistency and minimize message traffic for distributing information among client hosts and the federateServers. A dynamic filtering strategy (DFS), associated with the data distribution management (DDM) in the HLA RTI, is proposed to minimize false positive updates and enhance the filtering efficiency of subscription regions within an HLA federation. To verify the feasibility of this prototype, a distributed discrete event simulation application in Java was developed and performance of the proposed modeling design and Java RMI's distributed object model presented. From the experimental results, we show that the proposed environment based on HLA using 3LCM and DFS is workable and practical for supporting a large-scale distributed simulation.