NetSys 2015 Keynote Speakers

The NetSys’15 organizing committee is proud to announce the following keynote speakers for the conference.


Prof. Klara Nahrstedt
Prof. Klara Nahrstedt

Prof. Klara Nahrstedt

Klara Nahrstedt is the Ralph and Catherine Fisher Professor in the Computer Science Department, and Interim Director of Coordinated Science Laboratory in the College of Engineering at the University of Illinois at Urbana-Champaign. Her research interests are directed toward 3D teleimmersive systems, mobile systems, Quality of Service (QoS) and resource management, Quality of Experience in multimedia systems, and real-time security in mission-critical systems. She is the co-author of widely used multimedia books `Multimedia: Computing, Communications and Applications’ published by Prentice Hall, and ‘Multimedia Systems’ published by Springer Verlag. She is the recipient of the IEEE Communication Society Leonard Abraham Award for Research Achievements, University Scholar, Humboldt Award, IEEE Computer Society Technical Achievement Award, ACM SIGMM Technical Achievement Award, and the former chair of the ACM Special Interest Group in Multimedia. She was the general chair of ACM Multimedia 2006, general chair of ACM NOSSDAV 2007 and the general chair of IEEE Percom 2009.

Klara Nahrstedt received her Diploma in Mathematics from Humboldt University, Berlin, Germany in numerical analysis in 1985. In 1995 she received her PhD from the University of Pennsylvania in the Department of Computer and Information Science. She is ACM Fellow, IEEE Fellow, and Member of the Leopoldina German National Academy of Sciences.
Current real-time applications such as telepresence systems require a very strong real-time interactivity. Requirements are even more stringent in multi-stream and multi-site teleimmersive applications due to strong dependencies across geographically distributed streams. In this talk, I will talk about a cross-layer session-network control protocol (Software-Defined Network Northbound Protocol and Interface) for multi-stream and multi-site real-time applications, called OpenSession, which represents the interaction between the application-level controller and software-defined network (SDN) controller. Furthermore, OpenSession aims to improve interactivity, resource utilization and scalability by decoupling application layer data and control plane functionality, and partially offload the data plane functionalities to network layer switches. The control of network switches during the session run-time happens via OpenSession which then leverages the Software-Defined Networking (e.g., OpenFlow) assistance. The experiments with the cross-layer control session-network control are very encouraging, since OpenSession improves the performance, interactivity and resources usage of our real-time applications such as the 3D Teleimmersion at the data plane.

Dr. Norbert Meyer
Dr. Nobert Meyer

Dr. Nobert Meyer

Norbert Meyer is the head of HPC Department in the Poznań Supercomputing and Networking Center (PSNC). His research interests concern sustainability of e-Infrastructures, resource management in distributed environments, accounting, data management, technology of development graphical user interfaces and network security, mainly in the aspects of connecting independent, geographically distant domains (clouds, grids). The concept of remote operation, controlling and monitoring instrumentation of one of key research topics he is currently performing on national and international levels. He is the author and co-author of 70+ conference papers and articles in international journals, member of programme committees of international and national conferences. Norbert Meyer is a member of the e-IRG (e-Infrastructure Reflection Group), chair of the data management task force, member of ESFRI-e-IRG working groups, co-author of several white papers, member of STRATOS group, and member of steering committees of international projects. He coordinated the EU projects DORII and RINGRID, and has been participating in project proposals of the 5, 6 and 7 FP, e.g. CrossGrid, EGEE, CoreGRID, Expres, Phosphorus, int.eu.grid, NEXPRES, PRACE, PRACE-1IP, PRACE-2IP, EUDAT, IGE.
The e-Infrastructure plays a significant role in European Roadmap for RI (Research Infrastructure) defined by ESFRI (European Strategy Forum on Research Infrastructures) and e-IRG (e-Infrastructure Reflection Group). It is a base for further progress in R&D, co-operation between the science and industry, development of new technologies. We can say that the e-Infrastructure and its services are the major pillar of the European Research Area (ERA). The stakeholders of the infrastructure are technology providers (industry), service providers (NRENs, National Grids, national HPC centres), founders (usually Ministries of Science and Research in Member Countries, EC) and the scientists (universities, R&D centres).
The new challenges defined for Europe in the perspective of 2020 will be strongly connected with regions and a new approach called ‘smart regions’. The local and regional meaning of e-Infrastructure may entail the necessity of more intensive use because of specific regional needs. Some examples worth to be mentioned on the networking level are NRENs initiatives to build direct cross border connections between countries or regions e.g. BalticRing initiative in Nordic countries. The BalticGrid projects are good examples of past initiatives which tried to find applications specific for Baltic region.
Finally all European e-infrastructures and RI (Research Infrastructures) grow out from national initiatives. It forms international distributed environments. In Poland, the coordination of network resources is done by a consortium called Pioneer, consisting of 21 MANs - operators of city networks and national academic network operator PIONIER (PSNC). The network currently consists of more than 7000 km of fiber optic cables connecting virtually all universities and R & D entities. The data processing infrastructure consists mainly of HPC centers (5) connected by a network of 100 Gbps backbone (structural funds: NewMAN and 100Net), as well as other members of the consortium in the field of cloud and grid (projects: Platon, PL-GRID, MAN-HA, future ICT), advanced applications (POWIEW), storage systems (projects: KMD, Platon). The e-Infrastructure was put on the Polish list of key research infrastructures, updated in 2014 by the Ministry of Science and Higher Education.
There are many new challenges defined In HORIZON 2020, like environment protection, climate simulations, decreasing of energy consumption, regional tourism development, where we have to use the services of e-Infrastructure, more intensively on regional and international level.

Prof. Tadeusz Czachórski
Prof. Tadeusz Czachórski

Prof. Tadeusz Czachórski

Tadeusz Czachórski is a professor at the Silesian University of Technology, Gliwice, and director of the Institute of Theoretical and Applied Informatics of the Polish Academy of Sciences. He spent more than five years at several French universities and research institutes (IRISA Rennes, University of Versailles, Paris-Sud, Paris-Nord, National Institute of Telecommunication Evry). He also participated in Next Generation Internet and Future Generation Internet European where he was co-responsible for the work package on analytical, numerical and simulation methods to model performance of the Internet. Since 1990 is a member of the Committee of Informatics of Polish Academy of Sciences, currently the head of the section of computer networks and distributed systems of this committee. His scientific interests include mathematical methods and software related to modelling and performance evaluation of wide area computer networks.
Queueing models play an important role in modelling and performance evaluation of computer networks. Already the origins of queueing theory were related to the transmission of information: first queueing models were created a hundred years ago by Agner Krarup Erlang and by Tore Olaus Engset. Both of them were studying — in these days of human operators and cord boards to switch telephone calls by means of jack plugs — how many circuits were needed to provide an acceptable telephone service or how many telephone operators were needed to handle a given volume of calls.
In a computer network the total transmission time has two components. The first is composed of signal propagation time between nodes which is constant and determined by the length of links and the speed of light in the link. The second is packets waiting time at each node which is unknown and depends on the highly irregular current load of the network. It is estimated with the use of queueing models. In these models packets are the customers and the service time is the time needed to send a packet, bit-by-bit through an output gate of a router, hence its distribution is the same as the distribution of the size of the packets. Its estimation is important because it determines the quality of service measured by transmission time, its variability and loss rate.
Queueing models used in telecommunication are usually limited to steady-state analysis. It is in glaring contrast with the flows observed in real networks where the perpetual changes of traffic intensities are due to the nature of users, sending variable quantities of data, and also due to the performance of traffic control algorithms which are trying to avoid congestion in networks, e.g. the algorithm of congestion window used in TCP protocol which is adapting the rate of the sent traffic to the observed losses or transmission delays. The presentation discusses three most useful methods which may be applied in practice to analyse in a quantitative way transient states of queues in presence of time varying traffic, namely: numerical solution of Chapman-Kolmogorov equations for continuous time Markov chains with very large state space, diffusion approximation, and fluid flow approximation. Numerical examples coming from the author experience are presented.
Markov models are essential for the evaluation of the performance of computer networks. However, they are not scalable: the number of states is increasing rapidly with the complexity of a modelled object. At the moment we are able to generate and solve Markov chains having hundreds millions of states. A suitable method of solution is a projection method based on Krylov subspace with Arnoldi process to project the original chain onto a small Krylov subspace.
In diffusion approximation a diffusion equation (second order partial differential equation) defining the position of a particle in diffuse motion is used to describe the probability distribution of a queue length. This approach is merging states of the considered queueing system and needs much less computations than the Markov models.
Fluid-flow approximation is a simplified version of this method — only mean values of packet flows, queue length and service times are considered. Differential equations are simpler, and the computations can be completed in a reasonable time even for very large network topologies. It is also easier to model mechanisms used to control queues in nodes, e.g. the principles of IP congestion window and active queue management (RED mechanism) at IP routers.

Dr. Marc Dacier
Dr. Marc Dacier

Dr. Marc Dacier

Marc Dacier, Ph.D., is a Principal Scientist within the Cybersecurity Group at the Qatar Computing Research Institute (QCRI). He is helping building there a 50+ full time, permanent, researchers and engineers cybersecurity research team. Dr. Dacier holds a PhD, European Label, from the Institute National Polytechnique of Toulouse, France, which he obtained in 1994 after having worked for 3 years at LAAS-CNRS. After a year as a security consultant in Paris, France, he joined IBM Research in Zurich, Switzerland to form and lead the Global Security Analysis Laboratory. In 2002, he left IBM to become a professor at Eurecom, in Sophia Antipolis, France. Eurecom is one of the most active European research and training institutes in cybersecurity. Subsequent to his tenure with Eurecom, Marc joined Symantec to help form its European Research Labs and later direct all of the collaborative research projects carried out within the company in France, Ireland and in the United States. While at Symantec, he also spent two years in the USA overseeing university relationship management worldwide for Symantec Research Labs. An internationally recognized expert in computer and network security, Dr. Dacier has served on more than 60 program committees of major security and dependability conferences and as a member of the editorial board of several technical journals.
So called “BGP hijack attacks” consist in taking control over blocks of IP addresses without the consent of their legitimate owner. This could enable, in particular, malicious actors to send traffic using these stolen IPs but also to receive traffic sent to them, potentially leading to impersonation, man in the middle attack or even denial of services. The possible existence of these attacks have been known for almost ten years and anecdotal evidences of a very few cases have emerged since then. However, as of today, it remained an open conjecture if this was, or not, one of the techniques routinely used by attackers for their criminal mischiefs. In this talk, we will report on results obtained thanks to a worldwide framework of data collection and analysis, named SPAMTRACER, used for 18 months by Pierre Antoine Vervier, from Symantec Research Labs. We will show a number of converging pieces of evidence that tend to indicate that several BGP hijacks are taking place every day, in a very stealthy, automated and regular way.