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Multi-domain VNF mapping algorithms
No full textTelematics EngineeringUniversidad Carlos III de Madrid, Spainpu
Crowdsourcing Network and Traffic Measurements to Illuminate the Mobile Ecosystem
No full textTMA Keynotes announcement:
http://tma.ifip.org/program/keynote-speakers/As a society we have come to rely upon our mobile phones for myriad daily tasks. It is striking how little insight we, as mobile users and researchers, have into the operation and performance of our devices and network, into how (or whether) mobile apps protect the information we entrust to them, and with whom they share it. The research community (including the speaker) have energetically used a variety of
approaches to gain empirical understanding of the mobile
device/network ecosystem; however, these techniques have had to make tradeoffs that affect either the scale, scope or granularity of measurements. This talk describes how we leverage ideas from this prior work to design and develop mobile tools to characterize the behavior of mobile networks and mobile apps. Netalyzr for Android and Lumen are two user-friendly tools developed by ICSI that can imultaneously provide a valuable service to users and rich crowd-sourced data to reserachers. The talk will demonstrate its utility to researchers and average users alike by providing case studies on middlebox detection and characterization, mobile traffic characterization, identification of privacy and security risks inflicted by mobile apps, and network performance measurements.FALSEpu
Speedtest-like Measurements in 3G/4G Networks: the MONROE Experience
Get PDFMobile Broadband (MBB) Networks are evolving at
a fast pace, with technology enhancements that promise drastic improvements in capacity, connectivity, coverage, i.e., better performance in general. But how to measure the actual performance of a MBB solution? In this paper, we present our experience in running the simplest of the performance test: “speedtestlike” measurements to estimate the download speed offered by actual 3G/4G networks. Despite their simplicity, download speed measurements in MBB networks are much more complex than in wired networks, because of additional factors (e.g., mobility of users, physical impairments, diversity in technology, operator
settings, mobile terminals diversity, etc.).
We exploit the MONROE open platform, with hundreds of multihomed nodes scattered in 4 different countries, and explicitly
designed with the goal of providing hardware and software
solutions to run large scale experiments in MBB networks. We
analyze datasets collected in 4 countries, over 11 operators, from about 50 nodes, for more than 2 months. After designing the experiment and instrumenting both the clients and the servers with active and passive monitoring tools, we dig into collected data, and provide insight to highlight the complexity of running even a simple speedtest. Results show interesting facts, like the occasional presence of NAT, and of Performance Enhancing Proxies (PEP), and pinpoint the impact of different network configurations that further complicate the picture. Our results will hopefully contribute to the debate about performance assessment in MBB networks, and to the definition of much needed benchmarks for performance comparisons of 3G, 4G and soon of 5G networks.TRUEpu
Millimeter-Wave Beam Training Acceleration through Low-Complexity Hybrid Transceivers
Get PDFMillimeter-wave (mm-wave) communication systems can provide much higher data rates than systems operating at lower frequencies, but achieving such rates over sufficiently large distances requires highly directional beamforming at both the transmitter and receiver. These antenna beams have to be aligned very precisely in order to obtain sufficient link margin. In this paper, we first propose a parallel-adaptive beam training protocol which significantly accelerates the link establishment between mm-wave devices by exploiting the ability of hybrid analog-digital beamforming antennas to scan multiple spatial sectors simultaneously. Second, we deal with practical constraints of mm-wave transceivers and design a novel greedy geometric algorithm to synthesize sector beam patterns featuring configurable beamwidth and multi-beam radiation as required by the proposed beam training protocol. These multi-beam patterns are then also used for concurrent data communication over multiple paths, in case several suitable directions are found during the beam training. Simulation results show that our algorithm is able to shape antenna patterns very close to those attained by a fully-digital beamforming architecture, yet requires lower complexity hardware compared with state-of-the-art solutions. Exploiting such multi-beam antenna patterns, our parallel beam training protocol can provide up to 82% effective rate increase and 70% search time decrease compared to existing sequential protocols. The acceleration of the beam training phase shifts the optimum balance between the search overhead and the achieved directivity gain so that the best performance is reached with a training load 30% to 60% lower than that of sequential beam training.pu
Minimum cost solar power systems for LTE macro base stations
Get PDFThis paper proposes an algorithm for the identification of the minimum cost solution over a 10 year time horizon to power an LTE (Long-Term Evolution) macro base station, using a photovoltaic solar panel, a set of batteries, and optionally also a secondary power source, which can be a connection to a (possibly unreliable) power grid, or a small Diesel generator. The optimization is formalised as an Mixed Integer Programming (MIP) problem, which, after linearization, can be solved with CPLEX. A heuristic algorithm is also proposed, with the objective of decreasing the computational complexity of the optimization. Numerical results show that a hybrid solar-grid (or solar-diesel) power system saves a significant fraction of the total cost, compared to a pure solar system, and to the traditional power-grid system, over the investigated 10-year period, in a south European city, like Torino in Italy, as well as in a location close to the tropic, like Aswan in Egypt. Our proposed heuristic algorithm can be used to obtain a solution within 10–20% of the optimum, at a computational speed 200 times faster than the MIP solution.pu
Challenges in EU-China 5G Trials
No full textEU and China have, since many years, been investing in the fifth generation of mobile communication networks (5G) and are actively collaborating with global players in related activities, such as research and innovation, standardisation and spectrum.
This workshop aims at bringing together representatives from the key 5G initiatives in China and Europe, the IMT-2020 Promotion Group (China) and the 5G PPP (EU).
Telecom operators, vendors, service providers, universities and research institutes from both regions are invited to present the latest 5G developments, their future plans, and to discuss together concrete opportunities of collaboration in two hot topics of the 5G R&I area: i) 5G Trials and ii) The Internet of Connected Vehicles.
The workshop is co-organised by the Ministry of Industry and Information Technology (MIIT - China) and the Directorate-General for Communications Network, Content and Technology (DG CONNECT - EU).FALSEpu
Studying TLS Usage in Android Apps
Get PDFTransport Layer Security (TLS), has become the {\em de-facto} standard for secure Internet communication. When used correctly, it provides secure data transfer, but used incorrectly, it can leave users vulnerable to attacks while giving them a false sense of security. Numerous efforts have studied the adoption of TLS (and its predecessor, SSL) and its use in the desktop ecosystem, attacks, and vulnerabilities in both desktop clients and servers. However, there is a dearth of knowledge of how TLS is used in mobile platforms. In this paper we use data collected by Lumen, a mobile measurement platform, to analyze how Android apps use TLS in the wild. We analyze and fingerprint handshake messages to characterize the TLS APIs and libraries that apps use, and also evaluate weaknesses. We see that about 84% of apps use default OS APIs for TLS. Many apps use third party libraries; in some cases they are forced to do so because of restricted Android capabilities. Our analysis shows that both approaches have limitations, and that improving TLS security in mobile is not straightforward. Apps that use their own TLS configurations have vulnerabilities due to developer inexperience, but apps that use OS defaults are vulnerable to certain attacks if the OS is out of date, even if the apps themselves are up to date. We also study certificate verification and third-party libraries used in Android apps, and see low prevalence of security measures such as certificate pinning, even among high-risk apps such as those providing financial services, though we did observe major tracking and advertisement services deploying certificate pinning. We have made our dataset, which is the first of its kind, available to download to the public.TRUEpu
Exploring the statistical relation between the underwater acoustic and optical channels
Get PDFIn this paper, we are interested in finding whether a statistical relationship exists between underwater acoustics and optics, despite the different physics that govern these technologies. Besides the theoretical interest of such a relationship, predicting the quality of the optical links through acoustics is relevant for multimodal communications.
Our study is based on a large dataset acquired during the NATO ALOMEX 2015 expedition. The dataset consists of several acoustic and optical link characteristics measured at multiple locations, reflecting a diversity of sea environments. Our results, based on a systematic machine learning analysis, show a strong correlation between the properties of acoustic links and the reliability of optical communications. Potentially, this can be leveraged to predict the state of underwater optical links.TRUEpu
Big Data Analytics beyond the Single Datacenter
No full textDealing with big data is a major challenge for our society. The cloud offers a possible response to many needs of big data analytics. However, the cloud abstraction offers the illusion of ubiquitous resources which can mislead users to believe that \details" of cloud implementation such as location of cloud datacenters with respect to users does not matter. Such location-agnosticism can adversely affect performance when computing on data that is distributed or partitioned across several datacenters. We present several solutions for efficiently computing on such data.pu