George C. Polyzos

Dr. George C. Polyzos

Athens University of Economics and Business, Athens, Attikí, Greece
orcid

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 July 2013 in IEEE Communications Surveys & Tutorials
Verified
Journal Article
Closed access
George XylomenosGeorge Xylomenos
George Xylomenos
CVChristopher N. Ververidis
Christopher N. Ververidis
VSVasilios Siris
Vasilios Siris
NFNikos Fotiou
Nikos Fotiou
CTChristos Tsilopoulos
Christos Tsilopoulos
GPGeorge C. Polyzos
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.

1 January 1995 in IEEE Journal on Selected Areas in Communications
Verified
Journal Article
Closed access
KCK.C. Claffy
K.C. Claffy
HBH.-W. Braun
H.-W. Braun
GPGeorge C. Polyzos
George C. Polyzos
We present a parameterizable methodology for profiling Internet traffic flows at a variety of granularities. Our methodology differs from many previous studies that have concentrated on end-point definitions of flows in terms of state derived from observing the explicit opening and closing of TCP connections. Instead, our model defines flows based on traffic satisfying various temporal and spatial locality conditions, as observed at internal points of the network. This approach to flow characterization helps address some central problems in networking based on the Internet model. Among them are route caching, resource reservation at multiple service levels, usage based accounting, and the integration of IP traffic over an ATM fabric. We first define the parameter space and then concentrate on metrics characterizing both individual flows as well as the aggregate flow profile. We consider various granularities of the definition of a flow, such as by destination network, host-pair, or host and port quadruple. We include some measurements based on case studies we undertook, which yield significant insights into some aspects of Internet traffic, including demonstrating (i) the brevity of a significant fraction of IP flows at a variety of traffic aggregation granularities, (ii) that the number of host-pair IP flows is not significantly larger than the number of destination network flows, and (iii) that schemes for caching traffic information could significantly benefit from using application information

16 September 2008 in IEEE Communications Surveys & Tutorials
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Journal Article
Closed access
CVChristopher N. Ververidis
Christopher N. Ververidis
GPGeorge C. Polyzos
George C. Polyzos
This article surveys research in service advertising, discovery, and selection for mobile ad hoc networks and related issues. We include a categorization of service discovery architectures for MANETs and their modes of operation, presenting their merits and drawbacks. We pay particular attention to cross-layer service discovery - a special class of efficient service discovery approaches for MANETs. We also present security issues and discuss service description options, service selection mechanisms, and service-state maintenance techniques. We conclude with a summary, an outlook, and directions for future research in this area.

1 October 1993
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Conference Paper
Open access
PDF file
KCKimberly C. Claffy
Kimberly C. Claffy
GPGeorge C. Polyzos
George C. Polyzos
HBHans-Werner Braun
Hans-Werner Braun

1 January 1999
Verified
Conference Paper
Closed access
George XylomenosGeorge Xylomenos
George Xylomenos
GPGeorge C. Polyzos
George C. Polyzos
We present a comprehensive set of measurements of a 2.4 GHz DSSS wireless LAN and analyze its behavior. We examine issues such as host and interface heterogeneity, bidirectional (TCP) traffic and error modeling, that have not been previously analyzed. We uncover multiple problems with TCP and UDP performance in this system. We investigate the causes of these problems (radio hardware, device drivers, network protocols) and discuss the effectiveness of proposed improvements.

23 February 2011 in Telecommunication Systems
Verified
Journal Article
Closed access
PDF file
Nikos FotiouNikos Fotiou
Nikos Fotiou
DTDirk Trossen
Dirk Trossen
GPGeorge C. Polyzos
George C. Polyzos