Dimitris Varoutas

Economics of fixed broadband access network strategies

This article presents a comprehensive techno-economic evaluation of two upgrade strategy cases for broadband IP services for residential and business customers, and illustrates their respective merits and pitfalls, allowing the definition of a reasonable investment policy. The work should enable establishment of guidelines for broadband infrastructure upgrade strategies from the incumbent operators view. Following the definition of appropriate service sets, and taking into account demand scenarios established within the project, this work has been focused on developing a techno-economic model, based on the TONIC tool. Tariff structures have been applied to compute the key economic indicators, net present value, internal rate of return, and payback period. This investment analysis was carried using the tool, which was developed by IST-TONIC. The results show that the choice of technology (Ethernet or ATM) has almost no effect on the cost level and profitability of the cases. For the suburban area, a fiber to the cabinet solution is too expensive due to heavy infrastructure investments; for dense urban and urban areas the FTTC solution is worth the investments. The FTTH/office deployment scenario is only profitable in dense urban areas (>5000 potential customers/km/sup 2/) and already highly risky in the urban area.

Technoeconomic evaluation of the major telecommunication investment options for European players

This article summarizes the major results from European projects drawing final conclusions and recommendations from the technoeconomic evaluation of three telecommunications market studies. It presents an analysis addressing a wide range of crucial telecommunications questions debated today. The business cases are: seamless mobile IP service provision, 3G mobile virtual network operators (MVNO), and fixed networks for broadband IP services. Extensive market analysis has been carried out for modeling demand, penetrations, and tariff structures for new mobile services and broadband services as an input to the business cases. Results show that over a 10-year study period, UMTS business is profitable in most cases for established operators with reasonable market share. The 3G MVNO business case is profitable under typical conditions when MVNO yields about 10 percent penetration, depending on the country type. Provision of fixed broadband services with a fiber to the curb solution is viable in dense urban and urban areas, but not in suburban environments, while fiber to the home is viable only in dense urban areas, despite the selection of protocol (ATM vs. Ethernet). Furthermore, broadband wireless access (BWA) systems, in dense urban and urban areas, show quite promising economic results

Weather effects on FSO network connectivity

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 appear, thus making the design of strongly connected networks a demanding issue. In this paper, we consider a multiple-hop FSO network, where the nodes are distributed at fixed positions on a given path-link. We take account of the most critical weather phenomena, i.e., fog, rain, and snow, and derive analytical expressions for the node isolation probability, assuming a suitable path loss model. Next, we find the number of transceivers for a given path-link in order to achieve reliable performance. We also examine the reverse case; i.e., we find the total service length for a known number of FSO transceivers. The effect of the prime FSO modulation formats is also considered. The addressed analytical framework offers significant insights into the main factors that degrade the performance of FSO networks. It constitutes a valuable tool for telecom researchers to design such networks in practice.

OMEGA ICT project: Towards convergent Gigabit home networks

Gigabit home networks represent a key technology to make the future Internet success a reality. The OMEGA European project aims to define and demonstrate such networks. Consumers will require networks to be simple to install, without the need of any new wire. To achieve this, gigabit radio links and wireless optics communications will provide wireless connectivity within the home and its surroundings. Power-line communications potentially combined with robust RF will provides a home backbone ldquowithout new wires.rdquo To make this network ubiquitous, seamless and robust a technology-independent MAC layer will ensure its global control and provide connectivities to any number of devices the user wishes to connect to it in any room in a house or a flat. In order to make this vision come true, substantial progress is required in the fields of optical-wireless and RF physical layers, in protocol design, and in systems architectures.

On the Economics of 3G Mobile Virtual Network Operators (MVNOs)

The paper assesses the market conditions and dynamics, the architectures and the different approaches for deployment of 3G Mobile Virtual Network Operators (MVNOs), in an attempt to address specific advantages and pitfalls. Following the definition of appropriate service sets and tariff structures, and taking into account demand scenarios, a techno-economic model has been developed, in order to compute key economic indicators. The paper presents techno-economic results of specific business cases and deployment alternatives for an average “large” European country and a smaller, Nordic-type country. Fixed and variable costs have been identified and the business case shows how different service sets lead to different costs. Different MVNO business profiles have been investigated. Profitability for all scenarios and business profiles has been calculated, presented and discussed. Major opportunities and threats, as well as critical parameters and uncertainties have been identified through sensitivity analysis.

Techno-economic Evaluation of FTTC/VDSL and FTTH Roll-Out Scenarios: Discounted Cash Flows and Real Option Valuation

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 risks associated with the incumbents decision to invest in dense urban and urban areas are analyzed using both discount cash flow (DCF) analysis and real options analysis (ROA). The results revealed that in the case of investment subsidization, the option value to expand in a later phase can significantly improve the financial metrics of the business cases. The analysis made is based on the ECOSYS techno-economic methodology and tool.

Connectivity Issues for Ultraviolet UV-C Networks

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 of connectivity is more than important since it provides a strong indication of the network reliability and robustness. In the present study, we consider transmission with on-off keying and pulse position modulation schemes assuming both Gaussian and Poisson noise and adopt an effective experimental path loss model. Then, we evaluate the k-connectivity properties in terms of several network parameters. More precisely, we present and analyze the trade-off between node density and the degree of k-connectivity against other parameters (i.e., transmitted power, supported data rate, and error probability). The derived results are depicted using appropriate figures and tables and constitute the theoretical basis for the design and implementation of a reliable UV-C network in practice.

WiMAX on FSO: Outage Probability Analysis

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 simple but adequate scenario to investigate radio signal transmission over terrestrial optical wireless channels. An appropriate system architecture is adopted and a channel model, which entails some of the most critical impairments of the optical channel, i.e., attenuation, turbulence, pointing error effects, as well as of the RF channel, i.e., path loss, shadowing, and Rayleigh fading, is taken into account. The overall link budget and a closed-form of the outage probability of the system are deduced. Several analytical results are depicted using a realistic set of parameter values, to lend a helpful insight to the performance of the proposed architecture.

Evaluation of Optical Wireless Technologies in Home Networking: An Analytical Hierarchy Process Approach

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 of the analytic hierarchy process, five different optical home networking scenarios are identified and ranked. Within this framework, the importance of several economic, social and performance criteria is also evaluated. The obtained results are justified taking into account the technical particularities of each architecture. A sensitivity analysis is also performed to further elaborate on the results.

Business opportunities throughUMTS-WLAN networks

This article outlines the economic feasibility of mobile operators that combine nationwide mobility with 3G networks and hot spot coverage withWLANS, WLANS are based onHIPERLAN/2 architecture and theUMTS network exploitswCDMA/FDD technology. The evaluated business scenarios are focused on two different deployment areas, in terms of demographic characteristics and mobile penetration: a large and a small European country. The business case spans 2002 to 2011 withUMTS’ roll-out year in 2002 andWLAN’s in 2004, covering indoor hot-spot areas (stations, airports, stadiums, etc.) where demand is high. The demand for thisUMTS-WLAN roaming case is evaluated based on observations from Europe’s current mobile market and its evolution. Usage scenarios of different service packages corresponding to both residential and business markets have been taken into account. Direct investments and operational costs as well as revenue streams from traffic have been calculated. The methodology and the tool developed inACTS-TERA [1] andIST-TONIC [2] projects have been utilized for this case study. Economic conclusions have been derived, presented and discussed using key profitability factors. Profitability for all scenarios and business profiles has been calculated, presented and discussed. It includes a sensitivity analysis in order to identify the major opportunities and threats, for specific service sets as well as critical parameters and uncertainties. A wide audience from mobile operators and service providers to retail companies interested in entering the 3G market, can exploit this information.RésuméCet article souligne l’attrait pour les opérateurs mobiles que constitue la couverture des lieux publics à forte fréquentation par les réseauxRLAN en combinaison avec les réseaux 3G. les réseauxRLAN sont basés sur l’architectureHIPERLAN/2 et les réseauxUMTS sur la technologiewCDMA/FDD. Les scénarios économiques étudiés ont ciblé deux différents types de pays en terme de caractéristiques démographiques et de pénétration de la téléphonie mobile: un grand pays européen et un petit. Le plan d’affaire court sur 2002–2011 avec déploiementUMTS en 2002 et déploiementRLAN en 2004 pour la couverture des lieux publics à forte fréquentation tels que les gares, aéroports, stades, etc. où la demande est élevée. La demande dans ce modèle économique est estimée à partir de l’analyse du marché actuel de la téléphonie mobile en Europe et de son évolution. Les scénarios d’usage des différent services correspondant aux segments de marché entreprises et particuliers ont été pris en compte. Les investissements, le coût opérationnel ainsi que les revenus générés par le trafic ont été calculés. La méthodologie et l’outil développés dans les projets européensACTS-TERA etIST-TONIC ont été utilisés pour cette étude de cas. Les conclusions sont présentées avec une analyse de facteurs clés ainsi qu’une analyse de sensibilité incluant permettant d’identifier les principaux risques et opportunités.