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Economics of Traffic Attraction by Transit Providers
Get PDFhttp://dx.doi.org/10.1109/IFIPNetworking.2014.6857109Internet transit is an economy where providers sell traffic-delivery services. Traffic attraction refers to BGP (Border Gateway Protocol) techniques enabling an AS (Autonomous System) to receive traffic that would otherwise flow elsewhere. Unlike prior studies that present security perspectives on traffic attraction or deal with economic considerations in game-theoretic settings, this paper focuses on the economics of customer-traffic attraction by transit providers and report extensive simulations in an Internet-scale model configured with realistic data on traffic, topology, and pricing. We consider traffic attraction by tier-1 tier-2, and tier-3 networks with 3 types of reactions by other net-works: filtering, customer-disconnections, and attempts of losing ASes to attract traffic to themselves. Our results demonstrate that transit providers can derive substantial financial benefits from attracting customer traffic, with tier-1 networks being in the strongest position to do so. The traffic attraction remains effective despite the countermeasures unless participation in them is broad.TRUEpu
Performance Analysis of MAC for Power-Line Communications
Get PDFDOI:10.1145/2591971.2592033We investigate the IEEE 1901 MAC protocol, the dominant protocol for high data rate power-line communications. 1901 employs a CSMA/CA mechanism similar to - but much more complex than - the backoff mechanism of 802.11. Because of this extra complexity, and although this mechanism is the only widely used MAC layer for power-line networks, there are few analytical results on its performance. We propose a model for the 1901 MAC that comes in the form of a single fixed-point equation for the collision probability. We prove that this equation admits a unique solution, and we evaluate the accuracy of our model by using simulations.TRUEpu
Demo: Mobile Social Prefetcher using Social and Network Information
No full textThe load on mobile networks increased over the past years and is predicted to further grow rapidly. Mobile network operators are facing new challenges to deliver mobile data in a user-satisfying way. This situation can be improved, e.g., by offloading traffic to WiFi networks or by shifting traffic to times where good network conditions can be leveraged, e.g. non-peak hours. One way to offload content is speculative prefetching. By knowing which contents will be requested in the future allows to prefetch it in advance. To this end, the users’ content consumption has to be predicted. Furthermore, predicting properties of the smartphone’s mobile connectivity, e.g., strong signal, allows a better user experience as well as an optimized network resource allocation. The reason for this is that the packet loss, retransmission and congestions can be avoided. To this end, the Mobile Social Prefetcher app aims at relieving the mobile network in a two-fold way. On the one hand, prefetching of promising videos from the users Online Social Networks is performed if WiFi is available. Videos posted on the user’s OSN have been shown likely to be watched. On the other hand, if no prefetching opportunity can be used, a specific network optimized streaming is performed. This is provided by a video player which, both, reduces the load for the network operator
and decreases stalling events of video playbacks. The proposed approach prefetches videos from video posts on the user’s Facebook feed. Furthermore, the app considers
current and previously observed cellular network information of the smartphone to optimize the mobile data throughput. This way, both, the operators’ and the users’ needs are reflected by the approach demonstrated.TRUEpu
Experimenting with Floating Content in an Office Setting
Get PDFThe growing ubiquity and pervasiveness of sensors and smart devices, with the consequent availability of a large amount of “local” and contextualized information, are giving rise to a wealth of “context-aware” applications and services. In
this work we consider an opportunistic communication scheme
called “Floating Content” (FC), which was specifically designed for server-less distributed context-aware applications. So far the performance analysis of FC, and in particular of content lifetime and availability, was based on simplified system models and fluid system analysis. The resulting performance estimates did not account for the effects of propagation characteristics, of mobility patterns, and of communication protocols, all factors which are known to affect significantly the performance of opportunistic communication schemes. This paper studies the main issues related to the performance of the FC service in a realistic office setting, through a first experimental evaluation of a mobile app for Android devices. Our experimental results confirm the feasibility of the FC service for supporting practical context-aware mobile
applications in office settings.pu
Spectrum for the Masses: Networking in the Millimeter Wave Band
No full textState-of-the-art wireless communication already operates close to Shannon capacity and one of the most promising options to further increase data rates is to increase the communication bandwidth. Very high bandwidth channels are only available in the extremely high frequency part of the radio spectrum, the millimeter wave band (mm-wave). Upcoming communication technologies, such as IEEE 802.11ad, are already starting to exploit this part of the radio spectrum. However, communication at such high frequencies suffers from high attenuation and signal absorption, often restricting communication to line-of-sight (LOS) scenarios and requiring the use of highly directional antennas. This in turn requires a radical rethinking of wireless network design. On the one hand side, such channels experience little interference, allowing for a high degree of spatial reuse and potentially simpler MAC and interference management mechanisms. On the other hand, such an environment is extremely dynamic and channels may appear and disappear over very short time intervals, in particular for mobile devices. This talk will highlight some of the challenges of and possible approaches for networking in the mm-wave band.FALSEpu
Redes 5G: La revolución de las comunicaciones (5G Networks: the communications revolution)
No full texthttp://www.raing.es/es/noticias/la-rai-en-los-medios/redes-5g-la-revoluci-n-de-las-comunicacionesFALSEpu
NATalyser inhome NAT detection
No full textPresentation about the first functional version of NATalyser on Linux. Project Leone (From global measurements to local management): http://leone-project.eu/.TRUEpu
Special Section on Wireless Mobile and Multimedia Networks [Guest Editorial]
No full textGuest Editors: Albert Banchs and Balakrishnan Prabhakaran.TRUEpu
Trade-offs in Optimizing the Cache Deployments of CDNs
Get PDFContent delivery networks (CDNs) deploy globally distributed systems of caches in a large number of autonomous systems (ASes). It is important for a CDN operator to satisfy the performance requirements of end users, while minimizing the cache deployment cost. In this paper, we study the cache deployment optimization (CaDeOp) problem of determining how much server, energy, and bandwidth resources to provision in each cache AS, i.e., each AS chosen for cache deployment. The CaDeOp objective is to minimize the total cost incurred by the CDN, subject to meeting the end-user performance requirements. We formulate the CaDeOp problem as a mixed integer program (MIP) and solve it for realistic AS-level topologies, traffic demands, and non-linear energy and bandwidth costs. We also evaluate the sensitivity of the results to our parametric assumptions. When the end-user performance requirements become more stringent, the CDN footprint rapidly expands, requiring cache deployments in additional ASes and geographical regions. Also, the CDN cost increases several times, with the cost balance shifting toward bandwidth and energy costs. On the other hand, the traffic distribution among the cache ASes stays relatively even, with the top 20% of the cache ASes serving around 30% of the overall traffic.TRUEpu
Algorithmic Mechanisms for Reliable Master-Worker Internet-Based Computing
Get PDFISSN:0018-9340We consider Internet-based master-worker computations, where a master processor assigns, across the Internet, a computational task to a set of untrusted worker processors, and collects their responses. Examples of such computations are the “@home” projects such as SETI. In this work various worker behaviors are considered. Altruistic workers always return the correct result of the task, malicious workers always return an incorrect result, and rational workers act based on their self interest. In a massive computation platform, such as the Internet, it is expected that all three type of workers coexist. Therefore, in this work we study Internet-based master-worker computations in the presence of malicious, altruistic, and rational workers. A stochastic distribution of the workers over the three types is assumed. In addition, we consider the possibility that the communication between the master and the workers is not reliable, and that workers could be unavailable. Considering all the three types of workers renders a combination of game-theoretic and classical distributed computing approaches to the design of mechanisms for reliable Internet-based computing. Indeed, in this work we design and analyze two algorithmic mechanisms to provide appropriate incentives to rational workers to act correctly, despite the malicious workers’ actions and the unreliability of the communication. Only when necessary, the incentives are used to force the rational players to a certain equilibrium (which forces the workers to be truthful) that overcomes the attempt of the malicious workers to deceive the master. Finally, the mechanisms are analyzed in two realistic Internet-based master-worker settings, a SETI-like one and a contractor-based one, such as Amazon’s Mechanical Turk. We also present plots that illustrate the tradeoffs between reliability and cost, under different system parameters.TRUEpu