Jean Charles Domercant

Measuring the architectural complexity of military Systems-of-Systems

This research introduces a method to both characterize and measure complexity as it directly relates to military System-of-Systems (SoS) architectures. The complexity measure can then be used to support decision making during the acquisition of a complex system-of-systems that provides a suppression of enemy air defenses capability. The development of the complexity measure focuses on capturing the tradeoffs that occur among the complexity of the individual constituent systems, the interfaces that connect them, as well as the complexity that results from the coordination of numerous different activities, tasks, and functions that must be executed in a programmed sequence to fulfill a capability. The end result will be more informed decision making during the conceptual design phase and the selection of military system-of-systems architectures that achieve a balance between effectiveness and complexity.

A framework for the quantitative assessment of performance-based system resilience

Increasing system complexity and threat uncertainty require the consideration of resilience in the design and analysis of engineered systems. While the resilience engineering community has begun to converge on a definition and set of characteristics for resilience, methods for quantifying the concept are still limited in their applicability to system designers. This paper proposes a framework for assessing resilience that focuses on the ability of a system to absorb disruptions, recover from them, and adapt over time. The framework extends current approaches by explicitly considering temporal aspects of system responses to disruptions, volatility in system performance data, and the possibility of multiple disruption events. Notional system performance data is generated using the logistic function, providing an experimental platform for a parametric comparison of the proposed resilience metric with an integration-based metric. An information exchange network model is used to demonstrate the applicability of the framework towards system design tradeoff studies using stochastic simulations. The presented framework is domain-agnostic and flexible, such that it can be applied to a variety of systems and adjusted to focus on specific aspects of resilience.

Evaluating the agility of adaptive command and control networks from a cyber complex adaptive systems perspective

Command and control (C2) networks are critical components of modern military systems, enabling information sharing and communications between systems. These systems operate in complex environments characterized by uncertain and evolving threats, creating a need for agile C2 networks. This paper presents a Cyber Complex Adaptive Systems approach for assessing the agility of adaptive C2 networks. Agent-based modeling is used to simulate the performance of a C2 network connecting unmanned aerial vehicles for a collaborative surveillance mission. Due to the importance of information sharing in C2, information entropy-based awareness is used to quantitatively evaluate C2 performance. Complex network methods are used to define initial network topologies and threats. Network adaptation through random rewiring is shown to recover lost C2 capabilities following network attacks, and in some cases improve performance relative to initial topologies. Inverse average path length and largest connected component fraction are shown to be important factors for maintaining C2 awareness, with inverse average path length being the better indicator of awareness.

A reliability-based measurement of interoperability for systems of systems

The increasing complexity of net-centric systems of systems requires each system to be interoperable to achieve operational goals. Interoperability can be considered a metric of an architecture, and must be understood by decision makers as early as the conceptual design phase. Many measurements of interoperability of system pairs exist, but an architecture-level method for calculating interoperability of a system of systems is not currently available. This research presents a flexible, intuitive measure of interoperability of system pairs within a potential architecture performing a set of resource exchanges. It draws from reliability theory to incorporate system requirements and to link the interoperability of a system of systems with operational metrics of performance. This measure of interoperability could provide decision makers with information about an architecture and allow them to compare existing and potential systems of systems during the early phases of acquisition.

Metrics-based analysis and evaluation framework for engineering resilient systems

The DoDs ERS initiative calls for affordable, effective, and adaptable systems development. In support of this, a metrics-based analysis framework is introduced to address certain challenges for the design of future C2 military System-of-Systems (SoS). The interpretation of the concept of resilience, as well as a supporting threat analysis procedure for military SoS applications, have been the key driver for the evaluation of a systems ability to maintain its mission capability and health, when under attack due to given threats. An agent-based C2 UAV communication network application has been developed for the demonstration of the framework. Scenario-based case studies that involved communication jamming by the adversary forces are introduced for the evaluation the C2 systems response to a threat, including both degradation and recovery periods.

ARCNET: A System-of-Systems Architecture Resource-Based Collaborative Network Evaluation Tool

Rapid advances in information technology and the increased emphasis on joint operations results in highly networked, interoperable Systems-of-Systems (SoS). The units comprising the SoS must act in collaboration with each other to establish and maintain information superiority and battlespace dominance. The problem that arises, however, is that there are few Modeling & Simulation tools that exist for quantifying the benefits of collaboration during a military mission. To address this need, this paper details the application of an Architecture Resource-Based Collaborative Network Evaluation Tool (ARCNET). ARCNET provides an estimation of the impact on mission effectiveness resulting from changes in collaboration between military units. These changes may be due to differences in interoperability, resource exchanges, and force structure. Ultimately, this will lead to more robust decision making during military SoS architecture selection.

Designing resilient system-of-systems networks

The networked nature of many system-of-systems (SoS) requires consideration of resilience in their design and analysis. We present an approach for the design space exploration of such resilient SoS networks. We model candidate network designs using complex network methods, and generate and analyze a network design space with Design of Experiments. Results show an interaction between adaptation strategy and threat type, indicating that the best adaptation strongly depends on the threat faced. However, no interaction is seen with initial topology, suggesting that random initial topologies provide more resilience than scale-free ones regardless of the threat or adaptation strategy.

A system-of-systems approach for assessing the resilience of reconfigurable command and control networks

Increasing complexity and connectivity of military systems has created a need to investigate novel Command and Control (C2) approaches. In addition to being effective, C2 approaches must also be resilient to handle operating conditions characterized by uncertainty and mission volatility. This paper proposes an SoS approach to assessing C2 resilience, focusing on C2 architectures defined by information sharing and decision authority networks. Network reconfiguration based on random rewiring is used to improve the resilience of C2 architectures. C2 capability is measured by information entropy-based battlespace awareness and used as the primary metric for evaluating the resilience of C2 architectures. Awareness results are supplemented by complex network metrics to provide additional insights into the behavior of C2 architectures. An agent-based simulation of a network-centric unmanned aerial vehicle surveillance mission is used to simulate C2 architecture performance. Results show that random rewiring improves the resilience of C2 architectures to random and targeted node removal. Network largest component size is shown to accurately predict the awareness of a C2 architecture, indicating that C2 resilience can be achieved by maintaining network connectivity. Algebraic connectivity and inverse average path length also show similar trends to awareness. These results suggest the use of connectivity and path length network metrics to design reconfiguration strategies for C2 resilience.

An Evaluation Framework for Unmanned Aircraft Systems Integration in the National Airspace System

The National Airspace System (NAS) is a complex system defined by the interactions between aircraft and Air Traffic Control (ATC). As Unmanned Aircraft Systems (UAS) come to play an increasing role in domestic civil applications, the NAS will face unprecedented challenges to safely integrate these new systems and technologies into the existing regulatory framework. The focus of this research is to develop an evaluation framework that will aid in the future integration of UAS into the NAS. An Agent Based Modeling & Simulation approach is used to aid in the development of the evaluation framework. The primary objective is to aid decision makers so they may rigorously and transparently assess the impact of regulatory and technological requirements on UAS/NAS performance and safety. This objective is accomplished through the development of key metrics that enable both safety analysis and technology assessment to be conducted. These metrics can then be used to construct a visual analytic framework to further aid decision makers in setting new regulatory requirements.