Konstantinos V. Katsaros
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Featured researches published by Konstantinos V. Katsaros.
IEEE Communications Surveys and Tutorials | 2014
George Xylomenos; Christopher N. Ververidis; Vasilios A. Siris; Nikos Fotiou; Christos Tsilopoulos; Xenofon Vasilakos; Konstantinos V. Katsaros; George C. Polyzos
The current Internet architecture was founded upon a host-centric communication model, which was appropriate for coping with the needs of the early Internet users. Internet usage has evolved however, with most users mainly interested in accessing (vast amounts of) information, irrespective of its physical location. This paradigm shift in the usage model of the Internet, along with the pressing needs for, among others, better security and mobility support, has led researchers into considering a radical change to the Internet architecture. In this direction, we have witnessed many research efforts investigating Information-Centric Networking (ICN) as a foundation upon which the Future Internet can be built. Our main aims in this survey are: (a) to identify the core functionalities of ICN architectures, (b) to describe the key ICN proposals in a tutorial manner, highlighting the similarities and differences among them with respect to those core functionalities, and (c) to identify the key weaknesses of ICN proposals and to outline the main unresolved research challenges in this area of networking research.
Computer Networks | 2011
Konstantinos V. Katsaros; George Xylomenos; George C. Polyzos
It has become apparent for quite some time that the Internet has evolved from a network connecting pairs of end-hosts to a substrate for information dissemination. While this shift towards information centric networking has been clearly demonstrated by the proliferation of file sharing and content delivery applications, it has not been reflected in a corresponding shift in network architecture. To address this issue, we designed MultiCache, an information-centric architecture aiming at the efficient use of network resources. MultiCache is based on two primitives: multicast and caching. It exploits overlay multicast as a means for content delivery and takes advantage of multicast forwarding information to locate, in an anycast fashion, nearby caches that have been themselves fed via multicast. We evaluate MultiCache against a widespread file sharing application (BitTorrent) with respect to both network resource consumption and end-user experience.
IEEE Network | 2014
Konstantinos V. Katsaros; Wei Koong Chai; Ning Wang; George Pavlou; Herman Bontius; Mario Paolone
Largely motivated by the proliferation of content-centric applications in the Internet, information-centric networking has attracted the attention of the research community. By tailoring network operations around named information objects instead of end hosts, ICN yields a series of desirable features such as the spatiotemporal decoupling of communicating entities and the support of in-network caching. In this article, we advocate the introduction of such ICN features in a new, rapidly transforming communication domain: the smart grid. With the rapid introduction of multiple new actors, such as distributed (renewable) energy resources and electric vehicles, smart grids present a new networking landscape where a diverse set of multi-party machine-to-machine applications are required to enhance the observability of the power grid, often in real time and on top of a diverse set of communication infrastructures. Presenting a generic architectural framework, we show how ICN can address the emerging smart grid communication challenges. Based on real power grid topologies from a power distribution network in the Netherlands, we further employ simulations to both demonstrate the feasibility of an ICN solution for the support of real-time smart grid applications and further quantify the performance benefits brought by ICN against the current host-centric paradigm. Specifically, we show how ICN can support real-time state estimation in the medium voltage power grid, where high volumes of synchrophasor measurement data from distributed vantage points must be delivered within a very stringent end-to-end delay constraint, while swiftly overcoming potential power grid component failures.
IFIP'12 Proceedings of the 11th international IFIP TC 6 conference on Networking - Volume Part I | 2012
Konstantinos V. Katsaros; Nikos Fotiou; Xenofon Vasilakos; Christopher N. Ververidis; Christos Tsilopoulos; George Xylomenos; George C. Polyzos
Information-centric networking (ICN) is a paradigm that aims to better reflect current Internet usage patterns by focusing on information, rather than on hosts. One of the most critical ICN functionalities is the efficient resolution/location of information objects i.e., name resolution. The vast size of the information object namespace calls for a highly scalable and efficient name resolution approach. Currently proposed solutions either rely on a DHT structure, thus ensuring load balancing and scalability at the cost of inefficient routing, or on hierarchical structures, thus preserving routing efficiency at the cost of limited scalability. In this paper, we study in detail the tradeoff between state/signaling overhead versus routing efficiency for a generic name-resolution system based on a novel DHT scheme with enhanced routing properties, and compare it to DONA, an ICN architecture based on hierarchical resolution and routing.
modeling, analysis, and simulation on computer and telecommunication systems | 2009
Konstantinos V. Katsaros; Vasileios P. Kemerlis; Charilaos Stais; George Xylomenos
In the past few years numerous P2P file-sharing and content distribution systems have been designed, implemented, and evaluated via simulations, real world measurements, and mathematical analysis. Yet, only few of them have stood the test of time and gained wide user acceptance. BitTorrent is the one that holds the lions share among them and the reasons behind its success have been studied to a great extent with interesting results. Nevertheless, even though P2P content distribution remains one of the most active research areas, little progress has been made towards the study of the BitTorrent protocol (and its variations), in a fully controllable and realistic simulation environment. In this paper we describe and analyze a full-featured and extensible implementation of BitTorrent for the OMNeT++ simulation platform. Moreover, since we aim at realistic simulations, we present our enhancements on a popular conversion tool for practical Internet topologies, as well as our churn generator that is based on the analysis of real BitTorrent traces. Finally, we set forth the results from the evaluation of our prototype implementation regarding resource demands under different simulation scenarios.
IEEE Transactions on Smart Grid | 2015
Wei Koong Chai; Ning Wang; Konstantinos V. Katsaros; George Kamel; George Pavlou; Stijn Melis; Michael Hoefling; Bárbara Vieira; Paolo Romano; Styliani Sarri; Teklemariam Tsegay Tesfay; Binxu Yang; Florian Heimgaertner; Marco Pignati; Mario Paolone; Michael Menth; Erik Poll; Marcel Mampaey; Herman Bontius; Chris Develder
The evolution toward emerging active distribution networks (ADNs) can be realized via a real-time state estimation (RTSE) application facilitated by the use of phasor measurement units (PMUs). A critical challenge in deploying PMU-based RTSE applications at large scale is the lack of a scalable and flexible communication infrastructure for the timely (i.e., sub-second) delivery of the high volume of synchronized and continuous synchrophasor measurements. We address this challenge by introducing a communication platform called C-DAX based on the information-centric networking (ICN) concept. With a topic-based publish-subscribe engine that decouples data producers and consumers in time and space, C-DAX enables efficient synchrophasor measurement delivery, as well as flexible and scalable (re)configuration of PMU data communication for seamless full observability of power conditions in complex and dynamic scenarios. Based on the derived set of requirements for supporting PMU-based RTSE in ADNs, we design the ICN-based C-DAX communication platform, together with a joint optimized physical network resource provisioning strategy, in order to enable the agile PMU data communications in near real-time. In this paper, C-DAX is validated via a field trial implementation deployed over a sample feeder in a real-distribution network; it is also evaluated through simulation-based experiments using a large set of real medium voltage grid topologies currently operating live in The Netherlands. This is the first work that applies emerging communication paradigms, such as ICN, to smart grids while maintaining the required hard real-time data delivery as demonstrated through field trials at national scale. As such, it aims to become a blueprint for the application of ICN-based general purpose communication platforms to ADNs.
conference on computer communications workshops | 2010
Konstantinos V. Katsaros; George Xylomenos; George C. Polyzos
It has long been realized that the use of the Internet has moved away from its original end-host centric model. The vast majority of services and applications is nowadays focused on information itself rather on the end-points providing/consuming it. However, the underlying network architecture still focuses on enabling the communication between pairs of end-hosts, leading to a series of problems, such as the inefficient utilization of network resources, demonstrated by the proliferation of peer-to-peer (P2P) and file sharing applications. In essence, the prevailing end-to-end nature of the current Internet architecture prohibits network operators from controlling the traffic carried by their networks, leaving this control entirely to end users and their applications. In this paper, we investigate the potential benefits of MultiCache, an overlay network architecture aiming at handing control back to network operators. In MultiCache proxy overlay routers enable the delivery of data either via direct multicast, or via multicast fed caches residing at the leaves of multicast delivery trees. We study crucial aspects of our architecture, paying special attention to the properties of our distributed caching scheme, and investigate the feasibility of a progressive deployment of the proposed functionality over the existing Internet.
new technologies, mobility and security | 2012
Konstantinos V. Katsaros; George Xylomenos; George C. Polyzos
Having identified important limitations of the current Internet architecture, several research initiatives have engaged in the design of new architectures for the Internet of the Future. New features and protocols are designed, and in many cases, a clean slate approach is followed, advocating the replacement of almost the entire current protocol stack. In order to reliably evaluate the performance of such emerging protocols and architectures, we need a realistic evaluation framework reflecting current and forecasted traffic patterns. This is especially important for the emerging information-centric paradigm, where in-network caching plays an important role and network performance is heavily dependent on traffic characteristics. To this end, we have designed and implemented GlobeTraff, a traffic workload generator for the creation of synthetic traffic mixes. GlobeTraff supports several application traffic types, generated via models in the recent research literature, allowing the detailed parameterization of the respective models and the composition of the resulting traffic mix.
workshop on local and metropolitan area networks | 2007
Konstantinos V. Katsaros; George C. Polyzos
Recent advances in mobile communications and computing and strong interest of the scientific community in the Grid have led to research into the Mobile Grid. We discuss various approaches proposed in the literature and try to point out the fundamental issues and problems emerging from the introduction of mobile devices and wireless communications in the context of the Grid computing paradigm. We further propose an architecture for the realization of a Mobile Grid and investigate key design decisions and optimizations.
personal, indoor and mobile radio communications | 2007
Konstantinos V. Katsaros; George C. Polyzos
Recent advances in mobile communications and computing and strong interest of the scientific community in the Grid have led to research into the Mobile Grid. We discuss various approaches proposed in the literature and try to point out the fundamental issues and problems emerging from the introduction of mobile devices and wireless communications in the context of the Grid computing paradigm. We further propose an architecture for the realization of a Mobile Grid and investigate key design decisions and optimizations.