@conference {
	title = {Synchronization and Collision Avoidance in Non-Linear Flocking Networks of Autonomous Agents},
	author = {Somarakis, Christoforos., Paraskevas, Evripidis., Baras, John S., Motee, Nader.},
	year = {2016},
	month = {07/2016},
	abstract = {We introduce and discuss two novel second-order consensus networks with state-dependent couplings of CuckerSmale type. The first scheme models flocking to synchronization over a network of agents where the alignment of the agent{\textquoteright}s states occurs over a non-trivial limit orbit that is generated by the internal dynamics of each individual agent. The second scheme models the speed alignment of a group of agents which avoid approaching each other closer than a prescribed distance. While seemingly different, both of these systems can be analyzed using the same mathematical methods. We rigorously analyze both examples and reveal their striking similarities. We arrive at sufficient conditions that relate the initial configurations and the systems{\textquoteright} parameters that give rise to a collective common behavior. Simulation examples are presented to support our theoretical conclusions},
	address = {Athens, Greece},
	booktitle = {24th Mediterranean Conference on Control and Automation},
	pages = {pp. 1089-1094}
}
@conference {
	title = {Distributed Energy-Aware Mobile Sensor Coverage Game with Inter-Agent Communication},
	author = {Paraskevas, Evripidis., Maity, Dipankar., Baras, John S.},
	year = {2016},
	month = {07/2016},
	abstract = {Mobile Sensor Networks (MSN) are used to monitor large areas and collect measurements, e.g. temperature, humidity, or pressure data. Mobile sensors try to optimize their benefit from sensing a particular area, while keeping their energy consumption at the lowest possible level. We formulate this energy-aware sensor coverage problem as a potential game, where the mobile sensor nodes are considered as agents. The utility function of the game captures the trade-off between the benefit from coverage and the energy consumption. We also propose a distributed learning strategy for this potential game. The algorithm enables a bit-valued information exchange between the agents. Finally, it is proved that the learning rule converges to a Nash Equilibrium.},
	address = {Boston, Massachusetts},
	booktitle = {2016 American Control Conference},
	pages = {pp. 6259-6264}
}
@conference {
	title = {Trust-Aware Network Utility Optimization in Multihop Wireless Networks with Delay Constraints},
	author = {Paraskevas, Evripidis., Jiang, Tao., Purkayastha, Punyaslok., Baras, John S.},
	year = {2016},
	month = {06/2016},
	abstract = {Many resource allocation problems can be formulated as a constrained maximization of a utility function. Network Utility Maximization (NUM) applies optimization techniques to achieve decomposition by duality or the primal dual method. Several important problems, for example, joint source rate control, routing, and scheduling design, can be optimized by using this framework. In this work, we introduce an important network security concept, {\textquotedblleft}trust{\textquotedblright}, into the NUM formulation and we integrate nodes{\textquoteright} trust values in the optimization framework. These trust values are based on the interaction history between network entities and community-based monitoring. Our objective is to avoid routing packets through paths with large percentage of malicious nodes. We also add end-to-end delay constraints for each of the traffic flows. The delay constraints are introduced to capture the imposed quality of service (QoS) requirements for each traffic flow.},
	address = {Athens, Greece},
	booktitle = {24th Mediterranean Conference on Control and Automation},
	pages = {pp. 593-598}
}
@conference {
	title = {QoS Aware Component-Based Routing in Resource-Constrained Wireless Multi-Hop Networks},
	author = {Paraskevas, Evripidis., Baras, John S.},
	year = {2015},
	month = {11/2015},
	abstract = {With an increasing number of wireless devices available, there is a tremendous need for designing new efficient protocols, which take into account resource constraints and at the same time provide adequate Quality of Service (QoS) performance guarantees (e.g. throughput, latency etc.). Most wireless protocols currently used perform well under specific environmental conditions or in particular applications. In this work, we propose a novel methodology for designing routing protocols for resource-constrained wireless multi-hop networks by separating the protocol into distinct components, which specify particular functionalities. Different QoS requirements can be guaranteed by configuring the different components without the need to modify or develop the protocol from scratch. An initial study for energy-constrained environments indicated that our approach is effective. In our ongoing work we consider adversarial environments and we develop techniques to mitigate network-layer attacks. Finally, we are investigating the design of a decision-theoretic module for dynamic protocol configuration. Keywords- QoS performance, Routing, multi-hop networks},
	address = {San Fransisco, CA},
	booktitle = {23rd IEEE International Conference on Network Protocols (ICNP - PhD Forum )},
	pages = {pp. 476-478}
}
@conference {
	title = {Component Based Modeling of Routing Protocols for Mobile Ad Hoc Networks},
	author = {Paraskevas, Evripidis., Baras, John S.},
	year = {2015},
	month = {03/2015},
	abstract = {Routing protocols perform several functionalities and can be considered as complex software systems. The design and performance analysis of these protocols is difficult and complex and most of them are not adaptable to changes of the environment. In this paper, we present a component based methodology for modeling mobile ad hoc routing protocols. Componentization is used for modeling and analysis of complex systems, because it introduces modularity in protocol design and reusability of designed components across protocols of the same class. We define the fundamental components of the routing protocols based on their functionalities and investigate their interactions. More specifically, we present an initial investigation of the influence of the separate components on the performance metrics of the protocol, such as delay, packet delivery ratio and routing overhead. Proactive routing protocols are being examined and we consider OLSR and DSDV as use cases for our methodology. In addition, we propose an adaptive reusable modification in the Routing Metrics component of OLSR that lead to better overall performance in energy constrained environments.},
	address = {Baltimore, MD},
	booktitle = {49th Annual Conference on Information Sciences and Systems}
}
@conference {
	title = {Multi-Metric Energy Efficient Routing in Mobile Ad-Hoc Networks},
	author = {Paraskevas, Evripidis., Manousakis, Kyriakos., Das, Subir., Baras, John S.},
	year = {2014},
	month = {10/2014},
	abstract = {Increasing network lifetime by reducing energy consumption across the network is one of the major concerns while designing routing protocols for Mobile Ad-Hoc Networks. In this paper, we investigate the main reasons that lead to energy depletion and we introduce appropriate routing metrics in the routing decision scheme to mitigate their effect and increase the network lifetime. For our routing scheme, we take into consideration multiple layer parameters, such as MAC queue utilization, node degree and residual energy. We integrate our multi-metric routing scheme into OLSR, a standard MANET proactive routing protocol. We evaluate via simulations in NS3 the protocol modifications under a range of different static and mobile scenarios. The main observations are that in static and low mobility scenarios our modified routing protocol leads to a significant increase (5\%-20\%) in network lifetime compared to standard OLSR and slightly better performance in terms of Packet Delivery Ratio (PDR).},
	address = {Baltimore, Maryland},
	booktitle = {Military Communications Conference (MILCOM 2014)},
	pages = {pp. 1146-1151}
}
@article {
	title = {Convergence Analysis of Classes of Asymmetric Networks of Cucker-Smale Type with Deterministic Perturbations},
	author = {Somarakis, Christoforos., Paraskevas, Evripidis., Baras, John S., Motee, Nader.},
	year = {2017},
	month = {10/2017},
	abstract = {We discuss two nonlinear perturbed extensions of the Cucker-Smale model with asymmetric coupling weights. The first model assumes a finite collection of autonomous agents aiming to perform a consensus process in the presence of identical internal dynamics. The second model describes a similar population of agents that perform velocity alignment with the restriction of collision-free orbits. Although qualitatively different, we explain how these two non-trivial types of perturbations are analyzed under a unified framework. Rigorous analysis is conducted towards establishing sufficient conditions for asymptotic flocking to a synchronized motion. Applications of our results are compared with simulations to illustrate the effectiveness of our theoretical estimates.},
	pages = {pp. 1-11},
	journal = {IEEE transactions on control of network systems}
}
@article {
	title = {COBRAM: Component-Based Reusable Adaptive Mitigation for Mobile Ad-Hoc Networks},
	author = {M. A. Fecko, Manasoukis, Kyriakos., Paraskevas, Evripidis., Kang, J., Baras, John S., Young, K, Phoel. W.},
	year = {2017},
	month = {02/2017},
	abstract = {This paper presents component-based reusable~adaptive mitigation (COBRAM) - a novel framework for defending~against control and data plane attacks on wireless network~protocols. The COBRAM system consists of two main parts:~the mitigated protocol-components and the component activation~engine. It applies several novel mitigation techniques embedded~in the specific protocol components to maximize the reusability of~mitigations across multiple protocols and attacks. The activation~engine selects the appropriate mitigated component based on~the type of the detected attack(s) and the inferred network state.~An extensive performance evaluation showed that COBRAM can~restore network throughput to 60-88\% of the baseline with 44\%~of the nodes attacking, with outages limited to 5-20s.},
	journal = {IEEE Communication Magazine}
}
@techreport {
	title = {On the dynamics of linear functional differential equations with asymptotically constant solutions},
	author = {Somarakis, Christoforos., Baras, John S., Paraskevas, Evripidis.},
	year = {2015},
	month = {01/2015},
	abstract = {We discuss the dynamics of general linear functional differential equations with solutions that exhibit asymptotic constancy. We apply fixed point theory methods to study the stability of these solutions and we provide sufficient conditions of asymptotic stability with emphasis on the rate of convergence. Several examples are provided to illustrate the claim that the derived results generalize, unify and in some cases improve the existing ones.}
}
@techreport {
	title = {Stability by Fixed Point Theory in Time Delayed Distributed Consensus Networks},
	author = {Somarakis, Christoforos., Baras, John S., Paraskevas, Evripidis.},
	year = {2014},
	month = {09/2014},
	abstract = {We study the stability of linear time invariant distributed consensus dynamics in the presence of multiple propagation and processing delays. We employ fixed point theory (FPT) methods and derive sufficient conditions for asymptotic convergence to a common value while the emphasis is given in estimating the rate of convergence. We argue that this approach is novel in the field of networked dynamics as it is also flexible and thus capable of analyzing a wide variety of consensus based algorithms for which conventional Lyapunov methods are either too restrictive or unsuccessful.}
}
