Risk based resilient network design

This paper presents a risk-based approach to resilient network design. The basic design problem considered is that given a working network and a fixed budget, how best to allocate the budget for deploying a survivability technique in different parts of the network based on managing the risk. The term risk measures two related quantities: the likelihood of failure or attack, and the amount of damage caused by the failure or attack. Various designs with different risk-based design objectives are considered, for example, minimizing the expected damage, minimizing the maximum damage, and minimizing a measure of the variability of damage that could occur in the network. A design methodology for the proposed risk-based survivable network design approach is presented within an optimization model framework. Numerical results and analysis illustrating the different risk based designs and the tradeoffs among the schemes are presented. © 2011 Springer Science+Business Media, LLC

A Welfare Analysis of Spectrum Allocation Policies

Analysis of spectrum allocation policies in the economics literature focuses on competitive bidding for wireless licenses. Auctions generating high bids, as in Germany and the UK, are identified as "successful," while those producing lower receipts, as in Switzerland and the Netherlands, are deemed "fiascoes." Yet, even full and costless extraction of license rents does not map directly to social welfare, because spectrum policies creating rents impose social costs. For example, rules favoring monopoly market structure predictably increase license values, but reduce welfare. This paper attempts to shift analytical focus to the relationship between spectrum policy (including license auctions) and efficiency in output markets. In cross-country comparisons of performance metrics in mobile telephone service markets, empirical estimates suggest that countries that auction licenses do not achieve lower prices or higher levels of output than other nations. Rather, countries allocating greater bandwidth to licensed operators and achieving more competitive market structures realize demonstrable social welfare benefits. These gains generally dominate efficiencies associated with license sales. Policies to increase auction revenues, such as reservation prices and subsidies for weak bidders, should be evaluated in this light.

Reforming E-communications services: a critical assessment. In-depth analysis. CEPS Research Report, February 2017

This report analyses the proposed reform of the e-communications regulatory framework presented by the European Commission in September 2016. While many of the proposed changes appear meaningful, the report argues that overall the proposal does not entirely reflect the lessons learned from the past two decades of e-communications regulation in Europe, and ends up being at once too conservative (i.e. incremental with respect to legacy rules); fragile, since its effectiveness crucially depends on governance reform; and “retro”, since it does not incorporate principles of flexible, adaptive regulation in its overarching framework. The report argues that the merits of a lighter, ex post approach to e-communications were not sufficiently gauged by the European Commission in its impact assessment. The report was prepared at the request of Policy Department A and the IMCO Committee

Energy management in communication networks: a journey through modelling and optimization glasses

The widespread proliferation of Internet and wireless applications has produced a significant increase of ICT energy footprint. As a response, in the last five years, significant efforts have been undertaken to include energy-awareness into network management. Several green networking frameworks have been proposed by carefully managing the network routing and the power state of network devices. Even though approaches proposed differ based on network technologies and sleep modes of nodes and interfaces, they all aim at tailoring the active network resources to the varying traffic needs in order to minimize energy consumption. From a modeling point of view, this has several commonalities with classical network design and routing problems, even if with different objectives and in a dynamic context. With most researchers focused on addressing the complex and crucial technological aspects of green networking schemes, there has been so far little attention on understanding the modeling similarities and differences of proposed solutions. This paper fills the gap surveying the literature with optimization modeling glasses, following a tutorial approach that guides through the different components of the models with a unified symbolism. A detailed classification of the previous work based on the modeling issues included is also proposed

Genetic algorithms with immigrants and memory schemes for dynamic shortest path routing problems in mobile ad hoc networks

This article is posted here with permission of IEEE - Copyright @ 2010 IEEEIn recent years, the static shortest path (SP) problem has been well addressed using intelligent optimization techniques, e.g., artificial neural networks, genetic algorithms (GAs), particle swarm optimization, etc. However, with the advancement in wireless communications, more and more mobile wireless networks appear, e.g., mobile networks [mobile ad hoc networks (MANETs)], wireless sensor networks, etc. One of the most important characteristics in mobile wireless networks is the topology dynamics, i.e., the network topology changes over time due to energy conservation or node mobility. Therefore, the SP routing problem in MANETs turns out to be a dynamic optimization problem. In this paper, we propose to use GAs with immigrants and memory schemes to solve the dynamic SP routing problem in MANETs. We consider MANETs as target systems because they represent new-generation wireless networks. The experimental results show that these immigrants and memory-based GAs can quickly adapt to environmental changes (i.e., the network topology changes) and produce high-quality solutions after each change.This work was supported by the Engineering and Physical Sciences Research Council of U.K. underGrant EP/E060722/

A decomposition algorithm for local access telecommunications network expansion planning

Includes bibliographical references.Supported by a grant from GTE Laboratories, Inc., Waltham, Mass., and by a research award from the AT&T Foundation. Supported by a NATO Collaborative research grant. CRG 900281Anantaram Balakrishnan, Thomas L. Magnanti, Richard T. Wong

Transport optimization on complex networks

We present a comparative study of the application of a recently introduced heuristic algorithm to the optimization of transport on three major types of complex networks. The algorithm balances network traffic iteratively by minimizing the maximum node betweenness with as little path lengthening as possible. We show that by using this optimal routing, a network can sustain significantly higher traffic without jamming than in the case of shortest path routing. A formula is proved that allows quick computation of the average number of hops along the path and of the average travel times once the betweennesses of the nodes are computed. Using this formula, we show that routing optimization preserves the small-world character exhibited by networks under shortest path routing, and that it significantly reduces the average travel time on congested networks with only a negligible increase in the average travel time at low loads. Finally, we study the correlation between the weights of the links in the case of optimal routing and the betweennesses of the nodes connected by them.Comment: 19 pages, 7 figure

Communications Regulation in the Age of Digital Convergence : Legal and Economic Perspectives

This book brings together contributions of a distinguished panel of regulators as well as lawyers and economists from both academia and industry to present their insights on the digital convergence phenomenon in the telecommunications industry. The contributions cover a great deal of the relevant topics in communications regulation, such as technological and network neutrality, distribution of the digital dividend, and incentives for investment and innovation

What Really Matters in Spectrum Allocation Design

Since initiated in the U.S. in July 1994, auctions have replaced "beauty contests" in the assignment of wireless licenses in many countries. Economists have been involved in constructing the competitive bidding mechanisms chosen, and have devoted considerable analysis to the problems involved. Generally, auction methods have been evaluated according to the receipts generated; social gains resulting from the displacement of activity-distorting taxes has motivated the welfare analysis. Yet, policies widely advocated by economists to intensify license bidding , such as reservation prices or bidding credits for "weak"' bidders , may impose deadweight losses that dominate revenue raising efficiencies. Yet, retail market effects are largely excluded from cost-benefit calculations of rules to assign licenses. This paper reviews a number of case studies suggesting that economic analysis is most usefully focused on consumer welfare in wireless service markets, the outputs resulting from license use. Econometric evidence from mobile phone markets in twenty-nine countries suggests that auctions do not lower prices or increase usage, while liberalization, increased spectrum allocations and more competitive markets -- produces such pro-consumer results. We use simulations to compare the net social benefits of liberalization against policies suggested in the auction literature to enhance license bids. We argue that increases in bandwidth and competitiveness produce consumer benefits that generally dominate social gains from rent extraction via wireless license auctions.