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1915 research outputs found
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Priority Queueing for Packets with Two Characteristics
Get PDFModern network elements are increasingly required to deal with heterogeneous traffic. Recent works consider processing policies for buffers that hold packets with different processing requirement (number of processing cycles needed before a packet can be transmitted out) but uniform value, aiming to maximize the throughput, i.e., the number of transmitted packets. Other developments deal with packets of varying value but uniform processing requirement (each packet requires one processing cycle); the objective here is to maximize the total transmitted value. In this work, we consider a more general problem, combining packets with both nonuniform processing and nonuniform values in the same queue. We study the properties of various processing orders in this setting. We show that in the general case natural processing policies have poor performance guarantees, with linear lower bounds on their competitive ratio. Moreover, we
show several adversarial lower bounds for every priority queue and even for every online policy. On the positive side, in the special case when only two different values are allowed, 1 and V , we present a policy that achieves competitive ratio 1 + (W+2)/V, where W is the maximal number of required processing cycles. We also consider copying costs during admission.pu
The Impact of Quantization on the Design of Solar Power Systems for Cellular Base Stations
Get PDFIn this paper we focus on the design of the power system for off-grid cellular base stations powered by a photovoltaic (PV) solar panel and a battery. Several papers already tackled this problem, with different approaches, modeling either the day-to-day behavior, or the hourly dynamics. In addition, the meteorological characteristics were modeled using a variable number of levels. Different approaches produced different results, hardly comparable. In this paper, we discuss the choice of parameter quantization for time, weather, and energy storage, with the objective of deriving guidelines for the development of accurate and credible models that can support the power system design. Our investigation shows that quantization has an important impact on the mathematical model outputs. Hence, quantization must be carefully taken into account, to achieve a correct dimensioning of the power system.pu
This Is My Private Business! Privacy Risks on Adult Websites
Get PDFMillions of users from all over the world access
pornographic content on the web. However, as of today, there’s a dearth of knowledge about the porn web ecosystem and, in particular, about the privacy risks to which porn web users get exposed. As a matter of fact, porn websites can infer sensitive private information from users, including their sexual orientation and preferences, which can be later linked to their identity. As a result, many porn web consumers resort to ad blockers and private browsing modes to protect their identity when browsing adult websites. In this work in progress, we aim to expose the porn web ecosystem hoping to analyze aspects like their age verification mechanisms — which are required in certain regulatory frameworks as the British one —, their user
tracking and data collection practices, and their privacy policies.
By leveraging simple methodologies, we have already obtained
relevant preliminary results: (1) we have identified a significant presence of third-party tracking services on porn websites; (2) we have discovered the use of both first-party and third-party cookies, most times installed without the user consent; and (3) we have found a concerning lack of age verification mechanism to prevent the access of minors to porn websites. In the future, we plan to study in depth the many stakeholders in this industry as well as the effectiveness of anti-tracking mechanisms such as ad blockers, VPN services, and safe browsing modes.TRUEpu
Analysis of Spectral Properties for Efficient Coverage Under Probabilistic Flooding
No full textInformation dissemination plays a crucial role in modern network environments being an integral part of various vital processes (e.g., service discovery, data collection, routing). Probabilistic flooding has been proposed as a suitable alternative to blind flooding in order to reduce unnecessary transmissions and save valuable network resources. Under probabilistic flooding, an information message, initially located at some network node (i.e., the initiator node), is transmitted to neighbor nodes according to a forwarding probability attempting to reach all network nodes. This paper employs elements from algebraic graph theory to model probabilistic flooding behavior and derive analytical results regarding coverage (i.e., the number of nodes that have received the information message) and a lower bound of the forwarding probability allowing for global network outreach. It is also shown here, that for any value of the forwarding probability larger than this lower bound, (i) coverage under probabilistic flooding, is proportional to the initiator's node eigenvector centrality; and (ii) the probability for a node to receive the information message is proportional to the particular node's eigenvector centrality. Simulations performed for various topologies demonstrate the effectiveness of the proposed analytical model and support the analytical results.TRUEpu
A large-scale analysis of Facebook’s user-base and user engagement growth
Get PDFUnderstanding the evolution of the user-base as well as user engagement of online services is critical not only for the service operators but also for customers, investors, and users. While we can find research works addressing this issue in online services such as Twitter, MySpace or Google+, such detailed analysis is missing for Facebook, which is currently the largest online social network.
This paper presents the first detailed study on the demographic and geographic composition and evolution of the user-base and user engagement in Facebook over a period of three years. To this end, we have implemented a measurement methodology that leverages the marketing API of Facebook to retrieve actual information about the number of total users and the number of daily active users across 230 countries and age groups ranging between 13 and 65+.
The conducted analysis reveals that Facebook is still growing and geographically expanding. Moreover, the growth pattern is heterogeneous across age groups, genders, and geographical regions. In particular, from a demography perspective, Facebook shows the lowest growth pattern among adolescents. Gender based analysis showed that growth among men is still higher than growth in women. Our geographical analysis reveals that while Facebook growth is slower in western countries, it presents fastest growth in developing countries mainly located in Africa and Central Asia, analyzing the penetration of these countries also shows that these countries are at earlier stages of Facebook penetration. Leveraging external socioeconomic datasets we also showed that this heterogeneous growth can be characterized by indicators such as availability and access to internet, Facebook popularity, and factors related with population growth and gender inequality
5G-TRANSFORMER: Slicing and Orchestrating Transport Networks for Industry Verticals
Get PDFThis article dives into the design of the next generation mobile transport networks to simultaneously support the needs of various vertical industries with diverse range of networking and computing requirements. Network slicing has emerged as the most promising approach to address this challenge by enabling per-slice management of virtualized resources. We aim to bring the network slicing paradigm into mobile transport networks by provisioning and managing slices tailored to the needs of different vertical industries. Our technical approach is twofold: (i) enabling vertical industries to meet their service requirements within customized slices; and (ii) aggregating and federating transport networking and computing fabric, from the edge up to the core and cloud, to create and manage slices throughout a federated virtualized infrastructure. The main focus of the article is on major technical highlights of vertical-oriented slicing mechanisms for 5G mobile networks.pu
Investigating the deployability of VoIP services over wireless interconnected micro aerial vehicles
Get PDFEmerging technological devices, such as Unmanned Aircraft Vehicles (UAV) andSingle Board Computers (SBC), are being increasingly employed in recent years, thanks to the advances in electronics and the wide variety of sensors that are endowed. This paper aims at analyzing the viability of deploying multimedia services, focusing on the voice scenario, over wireless interconnected Micro AirVehicles (MAV), also known as drones. Toward this end, we assessed the performance both of the embedded wireless cards of current drones and also SBCs, which may be carried as payload in existing UAV solutions. Driven by the results obtained in these experiments, we then deployed an operational VoIP service over a network of commercial MAVs, to perform an experimental analysis on the resource capabilities of these devices and demonstrate that this type of service can certainly be used.pu
