Person | TU Delft Repository

Tom van den Berg

View Pure Profile

Authored

3 records found

Server-Side Experimentation

Common challenges from 12 organisations in The Netherlands

Conference paper - K.S. Anderson, Tom van den Berg, A. van Deursen

Background: experimentation is widely adopted within industry. Many large organisations have invested in their own infrastructure to be able to run experiments server-side. Objective: we wanted to investigate why organisations switch to server-side experimen- tation and which cha ...

Assessment of sectoral greenhouse gas emission reduction potentials for 2030

Journal article - K. Blok, Angélica Afanador, Irina Van Der Hoorn, Tom van den Berg, Oreane Y. Edelenbosch, Oreane Y. Edelenbosch, Detlef van Vuuren, Detlef van Vuuren

The aim of this article is to provide an overview of greenhouse gas emission reduction potentials for 2030 based on the assessment of detailed sectoral studies. The overview updates a previous assessment that dates back more than ten years. We find a total emission reduction pote ...

Developing modelling and simulation standards for including the cyber domain in military training and exercises

Conference paper - Bert Boltjes, E.C. Maathuis, Tom van den Berg, Rudi Gouweleeuw

As cyber operations are evolving to become a major military enabler, cyber activities and their resulting effects should also be represented in simulation environments. Currently much effort is being put into creating simulation environments to enable the simulation of cyber operations at the technical (network) level. At this level the focus is on detection and exploitation of vulnerabilities on the offensive side and on prevention, detection and mitigation of malicious intrusions on the defensive side. Simulations at this level facilitate training of and competition between cyber technicians. Typical examples are so-called “Capture-the-flag” events. However, cyber operations also have an important impact at the tactical, operational and strategical level, but so far little effort has been put into integration of cyber operations and their effects at these levels. What there is, is mainly limited to degrading some of the tactical data communication or switching off C2 systems or simulators. A standard approach is required to integrate offensive and defensive cyber activities and their resulting effects in simulation environments in a timely, efficient, interoperable, and cost-effective manner. A first requirement for a standard approach is to describe the elements of systems that can be affected by cyber operations, their characteristics, the way they interact, offensive and defensive cyber activities and the effects they can have on operational capabilities. For this purpose, taxonomies and ontologies for cyber operations have been described in the literature, but they only cover elements of cyber operations (tailored to specific attacks, threats, vulnerabilities et cetera). All these attempts serve a specific research purpose and there is limited or no coherence between them. With only one exception that we know of, the research results have, beside papers, not been available for further development. Open sources and standards are lacking which hinders further development of interoperable products for introducing cyber operations in modelling and simulation for training and experimentation as they do exist for Land, Sea, Air, and Space. An ontology for the cyber domain is – however – important to the development of (re-usable) simulation conceptual models, simulation scenarios and simulation data exchange models. An ontology provides amongst others consistent naming, meaning, relations and interactions of the various elements used in the different models. TNO Defence Research is strongly involved in many standardisation activities for modelling and simulation in the military domain. In addition, as part of a doctoral research project (Technical University Delft, TNO Defence Research, and Netherlands Defence Academy (NLDA)) aimed at assessing the effects of cyber operations in support of targeting decision making that avoids collateral damage. In this context computational ontologies have been developed to describe cyber operations and to represent and reason around the necessary knowledge to assess the effects of cyber operations. These ontologies can be regarded as a (knowledge-based) simulation environment resulting from empirical research and design studies in the military cyber domain. This paper describes a development method, focussed on the construction of a cyber operations ontology for training and exercises, and the initial steps toward a cyber simulation data exchange model.@en

Contributed

1 records found

Model-based testing of simulation models

A case-study approach to test model design for automated testing of discrete-event simulation models

Master thesis - F.G.A. van Bergeijk, A. Verbraeck, Yilin Huang, O. Quispel, Tom van den Berg

Model-based testing (MBT) is applied for the verification of simple simulation models used in modeling & simulation for decision-making. It is found that MBT of simulation models is not discussed much in literature, and that existing case studies on this topic do not give guidelines for test model design. It is established that testing simulation models is a difficult problem, as simulation models have many states, a time component, reactiveness, and inherent stochasticity. It is hypothesized that MBT could lead to more efficient and effective testing, and could fit within a modular approach to verification of simulation models. A focus is made on verification that discrete-event simulation models meet their functional requirements, by using automated test packages. Options for test model design are explored in three case studies where automated test suites are developed for three simple simulation models that form the systems under test (SUT). Options from existing taxonomies are first selected for this, based on their relevance to the properties of simulation models that make dynamic verification difficult. In the process, an existing MBT software tool is selected and evaluated. The main aspects of MBT that are explored are: nondeterministic test models and SUTs, transition-based test models, online and reactive test execution, specification of oracles at different levels, time advancement of the SUT, the distinction between black-box and white-box approaches, and the problem of test abstraction. Examples are made where the test model, an extended finite state machine (EFSM), is an abstract version of the SUT, that includes its most relevant state transitions. An approach to testing is used, where the test model follows the SUT’s state and selects relevant assertions accordingly. This approach limits the use of stochasticity in the test model, that is often done in MBT. It is found that MBT can be useful for three types of dynamic verification: of the dynamic behavior, of the (end) results, and of the response to inputs. The first type is explored with a step-by-step approach where oracles are checked after each time advancement in the SUT. The second type is implemented without the use of MBT techniques, by extending the functionality of an existing MBT tool to allow for analysis of multiple simulation runs. The third type is not explored but approaches for it are defined. The project shows the feasibility of MBT of simulation models and shows different options for test model design. Not discussed are the adequacy of the developed test packages in detecting faults, and the efficiency, effectiveness and quality of MBT for simulation models in general.