Dimitris Varoutas

Dimitris Varoutas
National and Kapodistrian University of Athens | uoa · Faculty of Informatics and Telecommunications

Associate Professor, SMIEEE

About

148
Publications
27,311
Reads
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1,716
Citations
Citations since 2017
32 Research Items
787 Citations
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2017201820192020202120222023020406080100120140
2017201820192020202120222023020406080100120140
Introduction
Dimitris Varoutas currently works at the Faculty of Informatics and Telecommunications, National and Kapodistrian University of Athens. Dimitris does research in Engineering, Physics and Economics. He is the Head of the newly established Department of Digital Industry Technologies and Director of Cultural Technologies Laboratory. He participates in several initiatives related to ICT development and Digital Heritage
Additional affiliations
September 2005 - present
National and Kapodistrian University of Athens
Position
  • Telecommunications Techno-Economics
January 2004 - present
National and Kapodistrian University of Athens
Position
  • Professor (Assistant)
February 1996 - June 2004
National and Kapodistrian University of Athens
Position
  • Researcher

Publications

Publications (148)
Article
Full-text available
The Digital Routes in Greek History's Paths (RoGH) project aims to provide a platform for disseminating cultural content relevant to Greek history to the general and specialised public. It comprises a web authoring tool for scientists, researchers and 3-D artists to upload historical multimedia content onto a specialised database. This content can...
Article
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Broadband (BB) communications lie at the heart of any developing information and digital society. Employing the Gompertz model in a time-series study, we analyze the factors that influence the diffusion of fixed and mobile broadband across the OECD countries that have been categorized into five groups based on the stage of innovation, between 1998...
Article
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Regulation of Next Generation Access Networks (NGANs) has been one of the most debated topics throughout the European Union (EU). Now it seems to be seeking to strike a new balance, between promoting NGANs investments and, simultaneously, preserving the current level of competition. This much-sought reconciliation was attempted with the release of...
Article
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In this paper, we present the development of a virtual reality application, namely “Roots in Greek History” or RoGH, which provides the user with a unique experiential travel or transfer back in time to specific historical periods and historical places which are part of the Greek history and its cultural heritage. The tool is a multi-purpose one wh...
Chapter
Smart Factory and 5th Generation Mobile Communication Systems gained much scientific and business attention during the years before the COVID-19 pandemic, as part of the so-called 4th Industrial Revolution (Industry 4.0). Even though there are second thoughts about whether the pandemic crisis will slow up Industry's 4.0 implementation, there has be...
Article
5G technology is not only a next-generation mobile network used for human communications, but also provides a worthy solution to machine-to-machine (M2M) communications requirements that contribute to the digital transformation of many vertical industries such as Factories of the future, Media and Entertainment, eHealth, Energy, among others. The a...
Article
According to the European Commission Recommendation for setting copper and fiber wholesale prices where cost orientation is imposed as a remedy, National Regulatory Authorities (NRAs) should adopt a Bottom-UP Long-Run Incremental Cost Plus (BU LRIC+) costing methodology that estimates the current cost that a hypothetical efficient operator would in...
Article
This study aims to reveal a set of important factors related to FTTH tariffs and potentially differentiate them among the different EU countries, when constructing a dataset of 28 EU countries between 2013 and 2018 with tariff data 30–100 Mbps (TR30) and 100+ Mbps (TR100). We find that there is a negative relationship between penetration and tariff...
Article
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Long-run forecasts of telecommunication services’ diffusion play an important role in policy, regulation, planning and portfolio decisions. Forecasting diffusion of telecommunication technologies is usually based on S-shaped models, mainly due to their accurate long-term predictions. Yet, the use of these models does not allow the introduction of r...
Chapter
This chapter enlightens how Industry 4.0 is gradually implemented in Cultural Industry. Even though Industry 4.0 started from manufacturing, it soon expanded to less technologically consuming industries, such as the Cultural, creating new opportunities especially in the field of Virtual Reality and Augmented Reality technologies. Taking into accoun...
Article
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The financial and economic crisis in Europe highlighted issues related to the competitiveness of member states, as well as the importance of measuring each country’s economic efficiency. Professional experts and the academic community are making efforts to develop appropriate strategies for each country to achieve sustainable growth. In the era of...
Article
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Digital competitiveness is gaining more and more attention as a source of competitive advantage at the business and national economies levels. Digital economy performance is a matter of national strategies for achieving economic growth and socioeconomic development. Widely accepted instruments for reporting progress in these areas have been recentl...
Conference Paper
This study examines the relevant factors that determine the FTTH tariffs within the European Union (EU) zone. FTTH networks, as a relevant new technology, have a significant impact on modern economies. This is reflected by their adoption and use across EU countries along with the increasing deployment. However, FTTH tariffs, play an important role...
Article
Whilst the deployment of next generation access networks (NGANs) is undoubtedly beneficial to the economy, new legal developments in the United States (US) regarding the issue of net neutrality (NN) pose a new challenge not only to policy makers but to telecommunication providers as well, that could justify a fresh approach when assessing NGANs inv...
Article
Full-text available
This paper analyzes the spectrum trading problem in virtualized fifth generation networks to enhance the network performance with respect to the spectrum utilization. The problem is modeled as a many‐to‐many matching game with utility‐based preferences and determines the matching between mobile network operators and mobile virtual network operators...
Chapter
Full-text available
This chapter enlightens how Industry 4.0 is gradually implemented in Cultural Industry. Even though Industry 4.0 started from manufacturing, it soon expanded to less technologically consuming industries, such as the Cultural, creating new opportunities especially in the field of Virtual Reality and Augmented Reality technologies. Taking into accoun...
Article
In rural areas in Europe, the deployment of High-Speed Broadband access networks lags far behind the urban and suburban areas due to difficulties of fiber rollout in the final meters. FTTC VDSL is the most widespread technology used for NGA network deployments in Europe but the coverage of VDSL networks is still limited in rural areas. FTTdp networ...
Article
Full-text available
Virtual reality (VR) technologies offer a unique opportunity in “3D reconstruction” of cultural monuments and historical cities that do not longer exist or have been modified (partially or totally). Even though technological capabilities are growing fast, emphasis is mainly given on developing virtual museums and exhibitions, while archaeological p...
Chapter
This research work describes the role of the Central Controller and Coordinator (C3) entity and its potential techno-economic gain when implemented in the upcoming 5G networks. We investigate how viable could be for a C3 Producer and for a cellular network Operator to produce and implement respectively the C3 entity in its network. The performance...
Article
Full-text available
Augmented Reality (AR) and Virtual Reality (VR) Technologies offer new challenges and opportunities for mediated communication and aspire to reshape business environment and everyday life in terms of user’s experience, enrich content, access and user-friendly capabilities). In this work, we focus on cultural sector and aim to discuss and present se...
Article
Full-text available
Telecommunications has entered a new age of development with advanced technology and increased competition with established players. The main focus of telecom operators is to maintain and increase their market shares by creating a loyal customer base and technology advancements. However, it remains difficult for telecom operators to evaluate their...
Conference Paper
Information and Communications Technologies (ICT) are a key factor which affects economic development and business growth significantly. However the assessment of whether and how ICT contributes to economic growth in general is a challenging topic, especially during periods of economic crisis. The study presented hereafter, aims to investigate the...
Conference Paper
The telecommunications market has significantly changed the last years with customer needs and competitive landscapes shifting in several ways. Fixed-mobile convergence in the telecom sector has been an interesting topic for a long time as important synergies, mergers and acquisitions between fixed and mobile operators are taking place all over the...
Conference Paper
The issue of Net Neutrality (NN), aimed at protecting consumer rights by preserving the openess of the Internet, has been fiercely debeted in the United States (US) and the European Union (EU) the last decade. To that aim, binding new rules were adopted on both sides of the Atlantic in 2015. But, as of now, US calls into question the necessity of t...
Conference Paper
Full-text available
The huge increase of mobile devices and user data demand has initiated efforts for more efficient mobile network solutions. To this direction, virtualization has attracted much attention as a promising solution for higher resource utilization and improved system performance. Therefore, basic on-demand wireless resource allocation approaches among m...
Article
In Electronic Marketplaces (EMs), a number of unknown entities can interact to conclude purchase actions. Interactions are, usually, between buyers and sellers. Both groups of entities (e.g., buyers, sellers) aim to acquire items in the most profitable price. The discussed interactions are realized in the form of negotiations over a number of items...
Chapter
Due to the rising progress of sustainable urban infrastructures, modeling realistic street networks is a fundamental challenge. This study contributes to this modeling direction, by suggesting the utilization of planar proximity graphs, and specifically the \(\beta \)-skeleton graphs. Their goodness of fit on producing real-like urban street networ...
Article
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Leadership and organizational culture are considered to be two of the most crucial organizational elements in order for firms to compete successfully and to gain sustainable advantage. We examine the interconnection between the aforementioned elements and create an empirical link based on data drawn from a competitive industry. The results indicate...
Article
For the realistic generation of synthetic street configurations, used in fiber-to-the-x (FTTx) dimensioning, the Gabriel graph model is proposed. Commencing the analysis with the Primal approach for 100 samples of urban street networks, a great heterogeneity is empirically discovered in their structural properties. Due to the observed morphological...
Article
The evolution of Internet and non-Internet users as well as the dynamics of their divide is studied using population biology concepts. Users׳ evolution and future trends are estimated by applying Lotka–Volterra model. The parameters of the proposed model are determined by both an analytical and a simulation method. The presented model is applied to...
Article
In this paper, optical wireless has been addressed as a promising technology to provide high-bandwidth services for underwater communications. However, the significant attenuation degree due to high absorption and scattering of optical transmission in the water confines the achievable range of optical links to only few meters. One way to achieve tr...
Article
The network topology has lately proved to be critical to the appearance of traffic congestion, with scale-free networks being the less affected at high volumes of traffic. Here, the congestion dynamics are investigated for a class of networks that has experienced a resurgence of interest, the networks based on the gravity model. In addition, supple...
Article
The special issue of Telecommunications Policy focuses on a number of selected papers from the 10th Conference in Telecommunications, Media and Internet Techno-economics. The contributions span techno-economic studies in fixed networks to business case analysis of mobile and Internet services investments, pointing to spring some indication of the c...
Article
The current regulatory framework in the European NGA market provides the basic principles for the gradual migration from service-based competition over the legacy copper access networks to facilities-based competition over fiber-based Next Generation Access (NGA) networks. This paper initially reviews the related literature and shows that: (i) an u...
Conference Paper
Full-text available
Network availability is of paramount importance in optical telecommunication networks. Their rising connectivity and consequently their availability is compromised by link and node failures, usually due to physical force (e.g. digging, earthquake or fire). Single link failures can in turn cause multiple failures in case a failure hits a shared risk...
Article
This article studies the impact of regulatory uncertainty on an incumbent’s incentives to undertake the socially optimal investments in NGA networks. Thus, a regulatory non-commitment setting in which the regulator sets the access price after the deployment of the NGA network is used. In particular, it is assumed that the regulator sets the access...
Conference Paper
Full-text available
This paper studies the incentives of an unregulated monopolist to undertake the socially optimal investment in NGA networks when it takes into account the fact that the NGA deployment is a two-dimensional investment decision concerning both the quality (or equivalently, technology) and the geographic coverage. It is found that both the privately an...
Article
Full-text available
Four-wave mixing (FWM) is one the limiting factors for existing and future wavelength division multiplexed optical networks. A semianalytical method based on Monte Carlo and Extreme Value theory is proposed and applied to study the influence of the FWM noise on the performance of WDM systems. The statistical behavior of the FWM noise is invest...
Conference Paper
Full-text available
In this study the structural properties of urban street networks of varying population density are analyzed. Samples from one hundred street networks from Greece are collected and the Primal approach is used to turn GIS data into spatial graphs. It is discovered that specific measures of street configuration are correlated with population density....
Conference Paper
Full-text available
This paper compares the impact of retail price discrimination and uniform pricing on a monopolist's incentives to extend its Next Generation Access (NGA) network deployment to less densely populated geographic areas. It is found that geographic price discrimination provides the monopolist with higher incentives to deploy a larger NGA network. In ad...
Conference Paper
Full-text available
As society progressively depends on large-scale telecommunications networks and their connectivity rapidly rises over time, it becomes of vital importance to study their topological features. On the backbone level uncertain disturbances of its constituent parts may affect a sizable proportion of the population, thus this can well explain the recent...
Article
Transferring wireless broadband services across extremely far distances on Earth is usually implemented nowadays either by ground-based or satellite communications. Terrestrial networks require, however, heavy installation and maintenance costs, whereas satellite networks suffer from excessively high power requirements. An alternative but highly ch...
Conference Paper
Full-text available
The impact of photonics in telecommunications is indisputably massive; however it relies on efficient cost reduction which is in turn only possible if significant cost savings are made at all steps in the development of the photonic device from the material to packaging. The PHOTOPOLIS consortium has identified polymer technology as the ideal solut...
Chapter
The globally observed recession of mobile services market has pushed mobile network operators into looking for opportunities to provide value added services on top of their high cost infrastructures. Recent advances in mobile positioning technologies enable services that make use of the mobile user location information, offering intuitive, attracti...
Conference Paper
Full-text available
The two most significant factors that affect the deployment of Next Generation Access (NGA) networks are the cost of the investment and the expected demand for the new fibre-based services. The related literature is based on very simplified assumptions regarding cost and demand structures. In particular, the investment cost is assumed to be increas...
Article
A system-of-systems (SoS) approach for wavelength-division multiplexing (WDM) and time-division multiplexing (TDM) fiber-to-the-home (FTTH) telecommunication networks is presented. Cost evolution curves for individual systems as well for whole FTTH WDM and TDM networks are presented. The analysis can be exploited for a fast and accurate analysis of...
Article
The use of relays is one of the most promising methods for mitigating impairments of the performance of free-space optical (FSO) systems and extending their limited transmission range. However, several factors contribute to significant link performance degradation. Most severe is the influence of the adverse atmospheric conditions that frequently a...
Article
The transmission of multiple wireless signals over optical links has attained a great research interest nowadays. In case where optical fibers are difficult to be deployed, or installation cost is prohibited, optical wireless systems provide an efficient alternative means. In this paper, we consider the WiMAX (IEEE802.16) standard and construct a s...
Article
The deployment of next generation access networks (NGAs) is investigated from technical, regulatory and investment perspectives. A brief review of the possible network architectures and deployment scenarios of NGAs is provided. Risk calculations of these NGA scenarios are performed based on a fully detailed techno-economic model. Furthermore, the e...
Conference Paper
Full-text available
The fixed access network is a major cost element for telecom operators that strongly depends on the underlying street network. In this paper the structural properties of nine urban street networks in Greece, grouped by their corresponding household and building density, are analysed based on Complex Network Theory principles. The Primal approach is...
Article
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This article examines the impact of input prices on an entrant’s make-or-buy decision and on the subsequent social welfare level for three alternative models of downstream competition. For each particular model, it derives the range of input prices that induce the entrant to undertake: (a) the productively efficient make-or-buy decision; and (b) th...
Article
A theoretical framework is proposed for the better understanding of the OSS global diffusion. Following a case study approach, the Apache web server's market potential is estimated, forecasted and examined in terms of the socio-economic factors determining its diffusion, across different economic environments in developed versus developing countrie...
Article
Full-text available
In this paper, a system of systems (SoS) framework for the reliability analysis of telecommunication networks is proposed. In this framework, two hazard analysis techniques, hazard and operability analysis and fault tree analysis, are combined in a hybrid scheme. This is further enhanced using the Bayesian network model along with sensitivity analy...
Article
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Home networks (HNs) will play a crucial role in achieving broadband service delivery and enabling the future Internet. Optical wireless (OW) is a promising technology for realizing this vision. This paper presents the main results of a roadmapping effort undertaken within the project ICT-OMEGA concerning the potential of OW HNs. Using the framework...
Article
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Home Networking Systems (HNS) play a crucial role in achieving broadband service delivery to end users and are quickly becoming the next arena for telecom operators and companies. This emphasizes the need for a technology roadmap in order to address several key issues associated with the deployment of these systems. The present paper presents the r...
Article
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Non-line-of-sight optical wireless transmission, operated in the unlicensed ultraviolet UV-C band, has been recently suggested as an alternative means of communication. However, due to limited coverage, relayed UV-C networks need to be deployed in order to supply communication services at large distances. In this paper, we consider a serial multi-h...
Article
Serious concerns have been raised, especially across Europe, about the role of regulation in network infrastructure investments. More specifically, the installation of optical fiber closer to customer premises, the so-called next generation access networks, requires massive investments in the face of demand and regulatory uncertainty. The purpose o...
Article
A sustainable business model is necessary for viable and future proof fiber-based Metropolitan Area Networks (MANs), in light of FTTH/O developments, which necessitate public initiatives, towards the leverage of broadband adoption. Following a detailed analysis and benchmarking of international practices, a pool of business solutions for the MANs d...
Article
This paper considers the impact of dual polarization adoption on the performance for a fixed wireless access (FWA) network. The major limiting factor of the performance in these systems is co-channel interference (CCI) originating from intracell and intercell concurrent transmissions. The proposed framework combines an appropriate time domain radio...
Article
Full-text available
Based on concepts of ecology modeling and specifically on population biology, a methodology for describing a high-technology market's dynamics is developed and presented. The importance of the aforementioned methodology is its capability to estimate and forecast the degree of competition, market equilibrium, and market concentration, the latter exp...
Article
Full-text available
This paper focuses on the connectivity issues of a non-line-of-sight (NLOS) optical wireless network operating in the ultraviolet UV-C spectral region. NLOS UV-C transmitters have a limited effective coverage and, hence, a dense node distribution is required in order to efficiently cover a large geographical area. Under this assumption, the concept...
Article
The innovation diffusion literature has established that the spread of a successful innovation over time typically follows a sigmoid curve. Therefore, the forecasting in this area has been monopolized by the use of well known aggregate diffusion models. Time series forecasting has been surprisingly neglected, as it provides mainly accurate short te...
Article
Full-text available
Passive optical networks (PONs) are being widely considered as a means to implement fiber-to-the-home (FTTH) and deliver broadband access to business and home users. However, technical and consequently regulatory and economic complexities arise in light of their deployment. In this paper, an evaluation of the business prospects of time division mul...
Conference Paper
Full-text available
Population characteristics such as density or dispersion are heavily used in exploring the viability of infrastructure investments and telecommunication networks' development, but not much attention has been paid to the effects of distribution of population sizes. In this paper, a fast method is presented for estimating the backbone network cost us...
Article
Full-text available
Due to the increasing demand in data rates telecom operators are faced with the question of when to upgrade their access network infrastructure toward fiber-to-the-home (FTTH). In this paper a techno-economic study of fiber-to-the-cabinet/very high bit rate digital subscriber line (FTTC/VDSL) and FTTH deployments is performed. The economics and ris...
Article
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Quick deployment, competition, and reduced prices have propelled the growth of mobile services in India much like in other developing and transitional countries. India has the second largest mobile subscriber base in the world, and continues to exhibit ...
Article
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This paper aims to propose a new framework for estimating and forecasting diffusion of high technology products, along with the construction of a price index. Into that context, the “diffusion–price” model is presented, as an innovative concept providing a long term estimation of both price and diffusion elasticity. This corresponds to the bidirect...