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On randomization in MTD systems

November 7, 2022
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Conference Paper
Author:
null
…
Published in:
Proc. of the 9th ACM Workshop on Moving Target Defense, MTD ’22, 7 November 2022.
Topic:
quantum systems and science
R&D area:
R&D group:

Summary

Randomization is one of the main strategies in providing security in moving-target-defense (MTD) systems. However, randomization has an associated cost and estimating this cost and its impact on the overall system is crucial to ensure adoption of the MTD strategy. In this paper we discuss our experience in attempting to estimate the cost of path randomization in a message transmission system that used randomization of paths in the network. Our conclusions are (i) the cost crucially depends on the underlying network control technology, (ii) one can reduce this cost by better implementation, and (iii) reducing one type of cost may result in increased costs of a different type, for example a higher device cost. These suggest that estimating the cost of randomization is a multivariable optimization problem that requires a full understanding of the system components.
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Summary

Randomization is one of the main strategies in providing security in moving-target-defense (MTD) systems. However, randomization has an associated cost and estimating this cost and its impact on the overall system is crucial to ensure adoption of the MTD strategy. In this paper we discuss our experience in attempting to...

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On randomization in MTD systems

The tale of discovering a side channel in secure message transmission systems

August 13, 2022
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Conference Paper
Author:
null
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Published in:
The Conf. for Failed Approaches and Insightful Losses in Cryptology, CFAIL, 13 August 2022.
Topic:
cryptography
R&D area:
R&D group:

Summary

Secure message transmission (SMT) systems provide information theoretic security for point-to-point message transmission in networks that are partially controlled by an adversary. This is the story of a research project that aimed to implement a flavour of SMT protocols that uses "path hopping" with the goal of quantifying the real-life efficiency of the system, and while failing to achieve this initial goal, let to the discovery a side-channel that affects the security of a wide range of SMT implementations.
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Summary

Secure message transmission (SMT) systems provide information theoretic security for point-to-point message transmission in networks that are partially controlled by an adversary. This is the story of a research project that aimed to implement a flavour of SMT protocols that uses "path hopping" with the goal of quantifying the real-life...

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The tale of discovering a side channel in secure message transmission systems

High quality of service in future electrical energy systems: a new time-domain approach

November 18, 2020
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Journal Article
Author:
null
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Published in:
IEEE Trans. on Sustainable Energy, vol. 12, no. 2, pp. 1196-1205, April 2021, doi: 10.1109/TSTE.2020.3038884.
Topic:
solar
R&D area:
R&D group:

Summary

In this paper we study dynamical distortion problems in future electrical energy systems with high renewable penetration. We introduce a new time-domain modeling of electrical energy systems comprising inverter-controlled distributed energy resources (DERs). This modeling is first used to quantify the relations between distortions and real/reactive power dynamics. Next, to ensure acceptable Quality of Service (QoS), a novel nonlinear distributed inverter control is introduced. Sufficient conditions are established for the guaranteed performance of the proposed control. These conditions further support the practical implementation of the derived controller. The effectiveness of this enhanced control is illustrated using simulations for the case of avoiding system instability during sudden grid reconfigurations. Simulations also show that distortions can be suppressed in systems with parallel-connected solar photovoltaics (PVs).
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Summary

In this paper we study dynamical distortion problems in future electrical energy systems with high renewable penetration. We introduce a new time-domain modeling of electrical energy systems comprising inverter-controlled distributed energy resources (DERs). This modeling is first used to quantify the relations between distortions and real/reactive power dynamics. Next, to...

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High quality of service in future electrical energy systems: a new time-domain approach

Toward distributed control for reconfigurable robust microgrids

October 11, 2020
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Conference Paper
Author:
null
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Published in:
2020 IEEE Energy Conversion Congress and Exposition, ECCE, 11-15 October 2020.
Topic:
energy systems
R&D area:
R&D group:

Summary

Microgrids have been seen as a good solution to providing power to forward-deployed military forces. However, compatibility, robustness and stability of current solutions are often questionable. To overcome some of these problems, we first propose a theoretically-sound modeling method which defines common microgrid component interfaces using power and rate of change of power. Using this modeling approach, we propose a multi-layered distributed control: the higher control layer participates in dynamic power management that ensures acceptable voltage, while the lower layer stabilizes frequency by regulating the dynamics to the power determined by the higher layer. Numerical and hardware tests are conducted to evaluate the effectiveness of the proposed control.
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Summary

Microgrids have been seen as a good solution to providing power to forward-deployed military forces. However, compatibility, robustness and stability of current solutions are often questionable. To overcome some of these problems, we first propose a theoretically-sound modeling method which defines common microgrid component interfaces using power and rate of...

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Toward distributed control for reconfigurable robust microgrids

Modeling and distributed control of microgrids: a negative feedback approach

December 11, 2019
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Conference Paper
Author:
null
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Published in:
2019 IEEE 58th Conf. on Decision and Control, CDC, 11-13 December 2019.
Topic:
microgrids
R&D area:
R&D group:

Summary

In this paper, we first show how general microgrid can be modeled as a negative feedback configuration comprising two subsystems. The first subsystem is the interconnected microgrid grid which is affected through negative feedback by the second subsystem consisting of all single-port components. This is modeled by transforming physical state variables into energy state variables and by systematically defining input and output of system components in this transformed state space. We next draw on the fact that for this basic feedback configuration there exist several types of conditions regarding subsystem properties which ensure overall system properties. In particular, we utilize dissipativity theory to propose a subsystem nonlinear control design for heterogeneous resource components comprising microgrids so that they jointly result in a closed-loop feasible and stable dynamical system for given ranges of system disturbances.
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Summary

In this paper, we first show how general microgrid can be modeled as a negative feedback configuration comprising two subsystems. The first subsystem is the interconnected microgrid grid which is affected through negative feedback by the second subsystem consisting of all single-port components. This is modeled by transforming physical state...

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Modeling and distributed control of microgrids: a negative feedback approach

Julia implementation of the Dynamic Distributed Dimensional Data Model

September 13, 2016
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Conference Paper
Author:
null
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Published in:
HPEC 2016: IEEE Conf. on High Performance Extreme Computing, 13-15 September 2016.
Topic:
high performance computing
R&D area:
R&D group:

Summary

Julia is a new language for writing data analysis programs that are easy to implement and run at high performance. Similarly, the Dynamic Distributed Dimensional Data Model (D4M) aims to clarify data analysis operations while retaining strong performance. D4M accomplishes these goals through a composable, unified data model on associative arrays. In this work, we present an implementation of D4M in Julia and describe how it enables and facilitates data analysis. Several experiments showcase scalable performance in our new Julia version as compared to the original Matlab implementation.
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Summary

Julia is a new language for writing data analysis programs that are easy to implement and run at high performance. Similarly, the Dynamic Distributed Dimensional Data Model (D4M) aims to clarify data analysis operations while retaining strong performance. D4M accomplishes these goals through a composable, unified data model on associative...

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Julia implementation of the Dynamic Distributed Dimensional Data Model

Forecast aids to lessen the impact of marine stratus on San Francisco International Airport

September 11, 2000
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Conference Paper
Author:
null
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Published in:
Proc. Ninth Conf. on Aviation, Range, and Aerospace Meteorology, 11-15 September 2000, pp. 317-322.
Topic:
air traffic control
R&D area:
R&D group:

Summary

San Francisco International Airport (SFO) is unable to use independent parallel approaches to its closely-spaced parallel runways when marine stratus is present in the approach. Delay programs are imposed to regulate the flow of traffic to match the true arrival capacity of the airport. Failure to forecast accurately the times of onset and dissipation of stratus in the approach results in unnecessary delays, costly airborne holding and diversions, or in wasted capacity as the traffic management planners fail to match the arrival rate to the actual airport capacity. Previous studies have shown that accurate 1-2 hour forecasts of the times of clearing in the approach could provide substantial reductions in the delays and inefficiencies associated with the marine stratus impacts on air traffic at SFO. The San Francisco Marine Stratus Initiative has provided a four-year focus on this problem and has resulted in the development of several forecast algorithms that will aid, the operational forecasting of the dissipation of marine stratus in the approach to SFO (Clark and Wilson, 1997). These algorithms involve new techniques for the analysis of observational data and statistical and dynamical prognosis of the behavior of the marine stratus. This discussion of the design and the performance of these algorithms provides an overview of the status of this project.
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Summary

San Francisco International Airport (SFO) is unable to use independent parallel approaches to its closely-spaced parallel runways when marine stratus is present in the approach. Delay programs are imposed to regulate the flow of traffic to match the true arrival capacity of the airport. Failure to forecast accurately the times...

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Forecast aids to lessen the impact of marine stratus on San Francisco International Airport
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