John S. Baras

Prof. Baras gave an invited lecture on Important Research Problems And Challenges In Complex Networks

Professor John S. Baras (ECE/ISR) recently (May 11, 2010) gave an invited lecture on important research problems and challenges in complex networks to the Large Scale Networksing (LSN) coordinating group (CG) of the Networking and Information Technology Research and Development (NITRD) program, at the National Science Foundation. The LSN CG of the NITRD Federal community, consists of senior research mangers and researchers in networking research and has a strong interest in assessing the capabilities and status of research on network complexity. Dr. Baras’s lecture was entitled “Complex Dynamic Metworks: Architectures, Games, Components, Probability” and his presentation can be found at http://www.nitrd.gov/Subcommittee/lsn.aspx. Dr. Baras described his recent research results on the foundations of network science including models of multiple interacting dynamic hypergraphs, collaboration in networks and constrained coalitional games, dynamic trust in networks, component-based network synthesis, effects of topology on performance, the need for new probability models, dynamics of biological networks and cancer research. He described the most promising and challenging problems for future research, emphasizing the interactions between multiple graphs used in network modeling, the need for developing a taxonomy of network architectures, the need to develop formal methods for compositional synthesis and verification of network protocols and the need for non-Kolmogorov probability models for representing the multitude of data in complex networks.

 The Networking and Information Technology Research and Development (NITRD) Program (http://www.nitrd.gov/about/about_nitrd.aspx) is the Nation's primary source of Federally funded revolutionary breakthroughs in advanced information technologies such as computing, networking, and software. The NITRD represents a unique collaboration of more than a dozen Federal research and development agencies. The LSN CG coordinates the activities of the Large Scale Networking Program Component Area (PCA). LSN members coordinate Federal agency networking R&D in leading-edge networking technologies, services, and enhanced performance, including programs in network security, new network architectures, heterogeneous networking (optical, mobile wireless, sensornet, IP,…), high data transport, federation across networking domains, testbeds, end-to-end performance measurement, and advanced network components; grid and collaboration networking tools and services; and engineering, management, and use of large-scale networks for scientific and applications R&D. The results of this coordinated R&D, once deployed, can help assure that the next generation of the Internet will be scalable, trustworthy, and flexible.

 

Date: May 11, 2010
Place: National Science Foundation

Professor John Baras (ECE/ISR) presented a distinguished lecture at United Arab Emirates University on June 1, 2010

Professor John Baras (ECE/ISR) presented a distinguished lecture at United Arab Emirates University on June 1. Baras was invited by former ISR Director Eyad Abed (ECE/ISR), dean of UAEU’s College of Information Technology.

Baras spoke about his research in security and trust in communication, information and social networks. Baras described recent results on physical layer security and authentication, using various "physical" characteristics of devices to provide much strengthened authentication and security. He also talked about the new technology of trusted platform modules (TPM) and various ways to incorporate it in wireless networks to strengthen their security, including their integration with physical device fingerprints and user biometrics. Baras also discussed why security should be implemented in a “cross layer” manner and talked about recent results on trust models and trust evaluation, both directly and indirectly.

In addition to his lecture, Baras met with the faculty, toured the Faculty of Information Technology’s laboratories, and learned about the university’s research priorities in discussions with the UAEU Provost. 

Date: June 1, 2010
Place: United Arab Emirates University

Prof. Baras gave the invited plenary lecture on Architectures, Modularity and Robustness in Networked Control System at the 9th International Federation of Automatic Control (IFAC) International Symposium on Dynamics and Control of Process Systems (DYCOPS 2010)

Professor John S. Baras (ECE/ISR), on July 5, 2010, gave the  invited plenary lecture, at the 9th International Federation of Automatic Control (IFAC) International Symposium on DYnamics and COntrol of Process Systems (DYCOPS 2010) (http://www.dycops2007.org/), which brings together engineers and scientists from universities, R & D laboratories and the process industries to focus attention on new methodologies and challenging applications within Process Systems Engineering in the context of industrial contexts and trends. DYCOPS 2010 was held at the Katholieke Universiteit Te Leuven, in Leuven, Belgium, July 5-7, 2010. The DYCOPS Symposium, is held every three years, and is a continuing series of international conferences, initiated in 1986.

Dr. Baras’ lecture was entitled “Architectures, Modularity and Robustness in Networked Control System,” and its theme was networked control systems which have become ubiquitous. The proliferation of information technology components and in particular networked embedded systems, has opened up new ways to connect systems, processes and agents, for better performance in many applications including manufacturing processes, chemical and biochemical processes, aerospace and automotive systems, communication, sensor and actuator networks. These distributed systems pose fundamentally new challenges as they collaborate to execute the basic “sense-decide-actuate” cycle of control systems, because the sensing, decision-making and actuation elements are not collocated and because they coordinate their activities through a network in a distributed asynchronous (at least partially) manner. Networked control systems are essentially distributed hybrid systems with multiple space-time scales and feedback loops.
In his plenary address Dr. Baras reviewed recent advances in this challenging and emerging area. He first described a novel framework for modeling and analysis of dynamic networked systems that utilizes several interacting dynamic hypergraphs. The simplest of the new class of models utilizes two hypergraphs: the collaboration one and the communication one. The collaboration hypergraph describes the time varying relation of collaboration between the systems; that is it answers the question: who has to collaborate with whom and when. The communication hypergraph describes the time varying communications that occur between the systems; that is it answers the question: who has to communicate with whom and when. He described a novel path-oriented characterization of these activities in networked control systems, as well as how multi-criteria optimization problems can be formulated and solved within this framework using a combination of algebraic and analytic tools.
Dr. Baras next presented a new fundamental way for analyzing networked control systems as networks of collaborating agents. The new fundamental view is that agents in such a network are dynamic entities that collaborate because via collaboration they can accomplish objectives and goals much better than working alone, or even accomplish objectives that they cannot achieve alone at all. Yet the benefits derived from such collaboration require some costs (or expenditures), for example due to communications. Or in equivalent terms, the collaboration is subject to constraints such as energy, communication, trust, organizational relations and structures. Understanding and quantifying this tradeoff between the benefits vs. the costs of collaboration, leads to new methods that can be used to analyze, design and control/operate networked control systems. He then proceeded to describe the dynamic constrained coalitional games mathematical framework, he has developed, which results in dynamic processes characterizing the evolution of the network over time, the so-called network formation process. He demonstrated how the metrics of benefit and cost control the dynamics, their convergence or divergence, and the structure of the resulting equilibria (i.e. generated networks), as well as how system architectures emerge from these considerations, and showed that some special network topologies are efficient from these benefits vs. costs tradeoffs.
As the final topic Dr. Baras described recent advances in model based systems engineering (MBSE), as a most promising new methodology for managing system complexity and for the development of quantitative methods and toolset frameworks for system synthesis, so as to meet requirements. He showed how components and compositional system architectures emerge from these considerations. He closed by describing how to combine these three fundamental methodologies for the analysis of: distributed optimization problems, the emergence of modules and components, networked systems robustness, compositionality and distributed algorithm performance versus network topologies. He presented applications in various areas including process control, biology, swarm optimization, that illustrated the basic ideas and algorithms,

Date: July 5, 2010
Paper Title: IFAC International Symposium
Place: Katholieke Universiteit Te Leuven, in Leuven, Belgium

Professor Baras gave an  invited semi-plenary lecture on Dynamic “Magic” Graphs in Cooperative Networked Systems at the 19th International Symposium on Mathematical Theory of Networks and Systems (MTNS2010)

Professor John S. Baras (ECE/ISR), on July 8, 2010, gave an  invited semi-plenary lecture, at the 19th International Symposium on the Mathematical Theory of Networks and Systems (MTNS2010), http://www.conferences.hu/mtns2010/ which at  the ELTE – University Congress Center, in Budapest, Hungary, 5-9 July 2010. The Symposium was hosted by Eötvös Loránd University (ELTE) and MTA SZTAKI (Computer and Automation Research Institute, Hungarian Academy of Sciences). The MTNS Symposia represent a prestigious prime conference series, held every two years, in the general area of mathematical systems theory.  The first MTNS was held at the University of Maryland College Par in 1972. MTNS traditionally covers areas involving a wide range of research directions in mathematical systems, networks and control theory, with emphasis on new challenges and potential applications.  A prime objective of the MTNS 2010 Symposium is to explore and present mathematics as a key technology for the 21st century.  

Dr. Baras’ lecture was entitled “Dynamic “Magic” Graphs in Cooperative Networked Systems”. Dr. Baras described emerging models for the ubiquitous networked systems that appear in so many current science and technology areas including infrastructure/communication networks, social/economic networks and biological networks. He first described his recently  developed novel framework for modeling and analysis of dynamic networked systems that utilizes several interacting dynamic hypergraphs. The simplest of the new class of models utilizes two hypergraphs: the collaboration one and the communication one. The collaboration hypergraph describes the time varying relation of collaboration between the systems; that is it answers the question: who has to collaborate with whom and when. The communication hypergraph describes the time varying communications that occur between the systems; that is it answers the question: who has to communicate with whom and when. Dr. Baras next presented a new fundamental way for analyzing networked control systems as networks of collaborating agents. The new fundamental view is that agents in such a network are dynamic entities that collaborate because via collaboration they can accomplish objectives and goals much better than working alone, or even accomplish objectives that they cannot achieve alone at all. Yet the benefits derived from such collaboration require some costs (or expenditures), for example due to communications. Or in equivalent terms, the collaboration is subject to constraints such as energy, communication, trust, organizational relations and structures. Understanding and quantifying this tradeoff between the benefits vs. the costs of collaboration, leads to new methods that can be used to analyze, design and control/operate networked control systems. He then described the dynamic constrained coalitional games mathematical framework, he has developed and demonstrated how the metrics of benefit and cost control the dynamics, their convergence or divergence, and the structure of the resulting equilibria (i.e. generated networks).

He then proceeded to describe the effects of the communication topology on the performance, and in particular the speed of convergence, of various distributed tasks in networked systems and demonstrated how small world graphs, and expander graphs emerge as efficient graphs for supporting distributed task execution. Expander graphs are graphs that have locally rich neighborhood connectivity but are globally sparse. He linked these results to practical applications such as energy efficiency, reputations in social networks and trust-aware networked systems. He described his results as the first results towards establishing a taxonomy of architecture vs. behavior in networked systems and described various inspirational paradigms from biology ranging from collaborating insects, to cell networks to the architecture of neural networks in mammalian brains. The “magic” graphs of his title are precisely these expander graphs that have a rich set of properties beneficial to collaborative systems and which were first discovered and analyzed in coding theory by Pinsker circa 1973, and have played an important role in coding theory including recent proofs of results on the famous Low Density Parity Codes studied by Gallager circa 1963. He reviewed the relation of expander graphs to minimal complexity electronic circuit design, design of good error correcting nodes, and deterministic error amplification in minimally randomized algorithms. He then described various methods to construct expander graphs, including optimization, perturbation and ZigZag product algorithms. Dr. Baras concluded by describing a rich set of theoretical and application problems emerging by applying expander graphs to networked systems.

Date: July 8, 2010
Place: Budapest, Hungary