Net neutrality, network capacity and innovation at the edges

We study how net neutrality regulations affect a high-bandwidth content provider (CP)'s investment incentives to enhance its quality of services (QoS) in content delivery to end users. We find that the effects crucially depend on whether the CP's entry decision is constrained by the Internet service provider (ISP)'s network capacity. If capacity is relatively large, prioritized services reduce the QoS investment as they become substitutes, but improve trafic management. With limited capacity, by contrast, prioritized delivery services are complementary to the CP's investments and can facilitate entry of congestionsensitive content; however, this creates more congestion for other existing content. Our analysis suggests that the optimal policy may call for potentially asymmetric regulations across mobile and fixed networks

Net neutrality, Network capacity and Innovation at the Edges

We study how net neutrality regulations affect a high-bandwidth content provider (CP)'s investment incentives to enhance its quality of services (QoS) in content delivery to end users. We find that the effects crucially depend on whether the CP's entry decision is constrained by the Internet service provider (ISP)'s network capacity. If capacity is relatively large, prioritized services reduce the QoS investment as they become substitutes, but improve trafic management. With limited capacity, by contrast, prioritized delivery services are complementary to the CP's investments and can facilitate entry of congestionsensitive content; however, this creates more congestion for other existing content. Our analysis suggests that the optimal policy may call for potentially asymmetric regulations across mobile and fixed networks

Net neutrality, Network capacity and Innovation at the Edges

We study how net neutrality regulations affect a high-bandwidth content provider (CP)'s investment incentives to enhance its quality of services (QoS) in content delivery to end users. We find that the effects crucially depend on whether the CP's entry decision is constrained by the Internet service provider (ISP)'s network capacity. If capacity is relatively large, prioritized services reduce the QoS investment as they become substitutes, but improve trafic management. With limited capacity, by contrast, prioritized delivery services are complementary to the CP's investments and can facilitate entry of congestionsensitive content; however, this creates more congestion for other existing content. Our analysis suggests that the optimal policy may call for potentially asymmetric regulations across mobile and fixed networks

Working at the edges

In this short article, the author explains how approaches to programme philosophy, curriculum structure and assessment design have liberated students to work creatively at the edges of their disciplines where they intersect with others. The article outlines the development of a Masters programme in Multidisciplinary Design Innovation

Recovering edges in ill-posed inverse problems: optimality of curvelet frames

We consider a model problem of recovering a function $f(x_1,x_2)$ from noisy Radon data. The function $f$ to be recovered is assumed smooth apart from a discontinuity along a $C^2$ curve, that is, an edge. We use the continuum white-noise model, with noise level $\varepsilon$. Traditional linear methods for solving such inverse problems behave poorly in the presence of edges. Qualitatively, the reconstructions are blurred near the edges; quantitatively, they give in our model mean squared errors (MSEs) that tend to zero with noise level $\varepsilon$ only as $O(\varepsilon^{1/2})$ as $\varepsilon\to 0$. A recent innovation--nonlinear shrinkage in the wavelet domain--visually improves edge sharpness and improves MSE convergence to $O(\varepsilon^{2/3})$. However, as we show here, this rate is not optimal. In fact, essentially optimal performance is obtained by deploying the recently-introduced tight frames of curvelets in this setting. Curvelets are smooth, highly anisotropic elements ideally suited for detecting and synthesizing curved edges. To deploy them in the Radon setting, we construct a curvelet-based biorthogonal decomposition of the Radon operator and build "curvelet shrinkage" estimators based on thresholding of the noisy curvelet coefficients. In effect, the estimator detects edges at certain locations and orientations in the Radon domain and automatically synthesizes edges at corresponding locations and directions in the original domain. We prove that the curvelet shrinkage can be tuned so that the estimator will attain, within logarithmic factors, the MSE $O(\varepsilon^{4/5})$ as noise level $\varepsilon\to 0$. This rate of convergence holds uniformly over a class of functions which are $C^2$ except for discontinuities along $C^2$ curves, and (except for log terms) is the minimax rate for that class. Our approach is an instance of a general strategy which should apply in other inverse problems; we sketch a deconvolution example

A Pedagogy for Original Synners

Part of the Volume on Digital Young, Innovation, and the UnexpectedThis essay begins by speculating about the learning environment of the class of 2020. It takes place entirely in a virtual world, populated by simulated avatars, managed through the pedagogy of gaming. Based on this projected version of a future-now-in-formation, the authors consider the implications of the current paradigm shift that is happening at the edges of institutions of higher education. From the development of programs in multimedia literacy to the focus on the creation of hybrid learning spaces (that combine the use of virtual worlds, social networking applications, and classroom activities), the scene of learning as well as the subjects of education are changing. The figure of the Original Synner is a projection of the student-of-the-future whose foundational literacy is grounded in their ability to synthesize information from multiple information streams

Competitive dynamics of lexical innovations in multi-layer networks

We study the introduction of lexical innovations into a community of language users. Lexical innovations, i.e., new terms added to people's vocabulary, play an important role in the process of language evolution. Nowadays, information is spread through a variety of networks, including, among others, online and offline social networks and the World Wide Web. The entire system, comprising networks of different nature, can be represented as a multi-layer network. In this context, lexical innovations diffusion occurs in a peculiar fashion. In particular, a lexical innovation can undergo three different processes: its original meaning is accepted; its meaning can be changed or misunderstood (e.g., when not properly explained), hence more than one meaning can emerge in the population; lastly, in the case of a loan word, it can be translated into the population language (i.e., defining a new lexical innovation or using a synonym) or into a dialect spoken by part of the population. Therefore, lexical innovations cannot be considered simply as information. We develop a model for analyzing this scenario using a multi-layer network comprising a social network and a media network. The latter represents the set of all information systems of a society, e.g., television, the World Wide Web and radio. Furthermore, we identify temporal directed edges between the nodes of these two networks. In particular, at each time step, nodes of the media network can be connected to randomly chosen nodes of the social network and vice versa. In so doing, information spreads through the whole system and people can share a lexical innovation with their neighbors or, in the event they work as reporters, by using media nodes. Lastly, we use the concept of "linguistic sign" to model lexical innovations, showing its fundamental role in the study of these dynamics. Many numerical simulations have been performed.Comment: 23 pages, 19 figures, 1 tabl

The Beginnings and Prospective Ending of “End-to-End”: An Evolutionary Perspective On the Internet’s Architecture

The technology of “the Internet” is not static. Although its “end-to- end” architecture has made this “connection-less” communications system readily “extensible,” and highly encouraging to innovation both in hardware and software applications, there are strong pressures for engineering changes. Some of these are wanted to support novel transport services (e.g. voice telephony, real-time video); others would address drawbacks that appeared with opening of the Internet to public and commercial traffic - e.g., the difficulties of blocking delivery of offensive content, suppressing malicious actions (e.g. “denial of service” attacks), pricing bandwidth usage to reduce congestion. The expected gains from making “improvements” in the core of the network should be weighed against the loss of the social and economic benefits that derive from the “end-to-end” architectural design. Even where technological “fixes” can be placed at the networks’ edges, the option remains to search for alternative, institutional mechanisms of governing conduct in cyberspace.