/pdf/the-theory-of-industrial-organization-19bejph0ej.pdf

The Theory of Industrial Organization

This Review summarizes the simultaneous transmission of several independent spatial channels of light along optical fibres to expand the data-carrying capacity of optical communications. Recent results achieved in both multicore and multimode optical fibres are documented.

/pdf/space-division-multiplexing-in-optical-fibres-9acl86j916.pdf

Space-division multiplexing in optical fibres

http://www.cs.unibo.it/~montesi/CBD/Articoli/SurvyBigData2.pdf

Data-intensive applications, challenges, techniques and technologies: A survey on Big Data

Optical networks are undergoing significant changes, fueled by the exponential growth of traffic due to multimedia services and by the increased uncertainty in predicting the sources of this traffic due to the ever changing models of content providers over the Internet. The change has already begun: simple on-off modulation of signals, which was adequate for bit rates up to 10 Gb/s, has given way to much more sophisticated modulation schemes for 100 Gb/s and beyond. The next bottleneck is the 10-year-old division of the optical spectrum into a fixed "wavelength grid," which will no longer work for 400 Gb/s and above, heralding the need for a more flexible grid. Once both transceivers and switches become flexible, a whole new elastic optical networking paradigm is born. In this article we describe the drivers, building blocks, architecture, and enabling technologies for this new paradigm, as well as early standardization efforts.

Elastic optical networking: a new dawn for the optical layer?

The Grid 2: Blueprint for a New Computing Infrastructure

Software defined hardware programmability and virtualization framework of network and computing is proposed and validated using FPGA-based infrastructure with complex data and image algorithms. The implemented platform is supported by function re-configurable System/Network on Chip.

Network, Compute and Storage Function Programmability and Virtualization: An FPGA-based Disaggregated System

Let us call a sequence of numbers heapable if they can be sequentially inserted to form a binary tree with the heap property, where each insertion subsequent to the first occurs at a leaf of the tree, i.e. below a previously placed number. In this paper we consider a variety of problems related to heapable sequences and subsequences that do not appear to have been studied previously. Our motivation for introducing these concepts is two-fold. First, such problems correspond to natural extensions of the well-known secretary problem for hiring an organization with a hierarchical structure. Second, from a purely combinatorial perspective, our problems are interesting variations on similar longest increasing subsequence problems, a problem paradigm that has led to many deep mathematical connections. 
We provide several basic results. We obtain an efficient algorithm for determining the heapability of a sequence, and also prove that the question of whether a sequence can be arranged in a complete binary heap is NP-hard. Regarding subsequences we show that, with high probability, the longest heapable subsequence of a random permutation of n numbers has length (1 - o(1)) n, and a subsequence of length (1 - o(1)) n can in fact be found online with high probability. We similarly show that for a random permutation a subsequence that yields a complete heap of size \alpha n for a constant \alpha can be found with high probability. Our work highlights the interesting structure underlying this class of subsequence problems, and we leave many further interesting variations open for future work.

Heapable Sequences and Subsequences

The elastic optical networks paradigm offers a competitive solution in terms of resource utilization to cope with the ever-increasing traffic demand. Specifically, the ability to make a number of previously fixed transmission parameters tunable, for example the data rate or channel spacing, requires an evolution of the node architecture. To fully benefit from elasticity, the data plane should evolve towards a software-defined architecture. In this paper, we report the work carried out in the ICT IDEALIST project and in particular the data plane solutions towards 1Tb/s optical networks with flexgrid and flex-rate technology. Flexibility requires changes in optical cross-connect, transponder as well as in the digital layer. The consortium builds pre-commercial experimental testbeds to validate the proposed building blocks and to analyze candidate applications.

IDEALIST data plane solutions for elastic optical networks

This paper presents an application-aware ingress interface for dynamic OBS networks. Aggregation mechanisms that consider application requirements have been simulated and experimentally demonstrated on the testbed.

Application-aware ingress interface for dynamic OBS networks

Consumer reviews are now part of everyday decision-making. Yet, the credibility of these reviews is fundamentally undermined when businesses commit review fraud, creating fake reviews for themselves or their competitors. We investigate the economic incentives to commit review fraud on the popular review platform Yelp, using two complementary approaches and datasets. We begin by analyzing restaurant reviews that are identified by Yelp's filtering algorithm as suspicious, or fake ? and treat these as a proxy for review fraud (an assumption we provide evidence for). We present four main findings. First, roughly 16% of restaurant reviews on Yelp are filtered. These reviews tend to be more extreme (favorable or unfavorable) than other reviews, and the prevalence of suspicious reviews has grown significantly over time. Second, a restaurant is more likely to commit review fraud when its reputation is weak, i.e., when it has few reviews, or it has recently received bad reviews. Third, chain restaurants ? which benefit less from Yelp ? are also less likely to commit review fraud. Fourth, when restaurants face increased competition, they become more likely to receive unfavorable fake reviews. Using a separate dataset, we analyze businesses that were caught soliciting fake reviews through a sting conducted by Yelp. These data support our main results, and shed further light on the economic incentives behind a business's decision to leave fake reviews.

Georgios Zervas

Papers

Network, Compute and Storage Function Programmability and Virtualization: An FPGA-based Disaggregated System

Heapable Sequences and Subsequences

IDEALIST data plane solutions for elastic optical networks

Application-aware ingress interface for dynamic OBS networks

Fake It Till You Make It: Reputation, Competition, and Yelp Review Fraud