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Proceedings of the 22nd International Conference Information Visualisation, IV 2018, Fisciano, Italy, July 10-13, 2018
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End to End 5G Measurements with MONROE: Challenges and Opportunities
Get PDFTo be able to support diverse requirements of massive number of connected devices while also ensuring good user experience, 5G networks will leverage multi-access technologies, deploy supporting operational mechanisms such as SDN and NFV, and require enhanced protocols and algorithms. For 4G networks, MONROE has been key to provide a common measurement platform and a set of methodologies available to the wider community. Such common grounds will become even more important and more challenging with 5G. In this paper, we elaborate on some key requirements for the design and implementation of 5G technologies and highlight the key challenges and needs for new solutions as seen in the context of 5G end-to-end measurements. We then discuss the opportunities that MONROE provides and more specifically, how a 5G-capable MONROE platform could facilitate these efforts.TRUEpu
Nanosecond-precision Time-of-Arrival Estimation for Aircraft Signals with low-cost SDR Receivers
Get PDFPrecise Time-of-Arrival (TOA) estimations of aircraft and drone signals are important for a wide set of applications including aircraft/drone tracking, air traffic data verification, or self-localization. Our focus in this work is on TOA estimation methods that can run on low-cost software-defined radio (SDR) receivers, as widely deployed in Mode S / ADS-B crowdsourced sensor networks such as the OpenSky Network. We evaluate experimentally classical TOA estimation methods which are based on a cross-correlation with a reconstructed message template and find that these methods are not optimal for such signals. We propose two alternative methods that provide superior results for real-world Mode S / ADS-B signals captured with low-cost SDR receivers. The best method achieves a standard deviation error of 1.5 ns.TRUEpu
Adaptive Codebook Optimization for Beam Training on Off-the-Shelf IEEE 802.11ad Devices
Get PDFhttps://doi.org/10.1145/3241539.3241576Beamforming is vital to overcome the high attenuation in wireless millimeter-wave networks. It enables nodes to steer their antennas in the direction of communication. To cope with complexity and overhead, the IEEE 802.11ad standard uses a sector codebook with distinct steering directions.
In current off-the-shelf devices, we find codebooks with generic pre-defined beam patterns. While this approach is simple and robust, the antenna modules that are typically deployed in such devices are capable of generating much more precise antenna beams. % that can actively adapt to the current channel. % and exploiting reflected signal paths.
In this paper, we adaptively adjust the sector codebook of IEEE 802.11ad devices to optimize the transmit beam patterns for the current channel. To achieve this, we propose a mechanism to extract full channel state information (CSI) regarding phase and magnitude from coarse signal strength readings on off-the-shelf IEEE 802.11ad devices. Since such devices do not expose the CSI directly, we generate a codebook with phase-shifted probing beams that enables us to obtain the CSI by combining strategically selected magnitude measurements. Using this CSI, transmitters dynamically compute a transmit beam pattern that maximizes the signal strength at the receiver. Thereby, we automatically exploit reflectors in the environment and improve the received signal quality. Our implementation of this mechanism on off-the-shelf devices demonstrates that adaptive codebook optimization achieves a significantly higher throughput of about a factor of two in typical real-world scenarios.
Demo: https://joanguitar.github.io/ACO/wip
https://joanguitar.github.io/ACO/wip
Repositorio: https://github.com/Joanguitar/ACO
https://github.com/Joanguitar/ACOTRUEpu
Formalizing Compute-Aggregate Problems in Cloud Computing
Get PDFEfficient representation of data aggregations is a fundamental problem in modern big data applications, where network topologies and deployed routing and transport mechanisms play a fundamental role to optimize desired objectives: cost, latency, and others. We study the design principles of routing and transport infrastructure and identify extra information that can be used to improve implementations of computeaggregate tasks. We build a taxonomy of compute-aggregate services unifying aggregation design principles, propose algorithms for each class,
analyze them, and support our results with an extensive experimental study.TRUEpu
POSENS: A Practical Open Source Solution for End-to-End Network Slicing
Get PDFNetwork slicing represents a new paradigm to operate mobile networks. With network slicing, the underlying infrastructure is “sliced” into logically separate networks which can be customized to the specific needs of their tenant. Hand-on experiments on this technology are essential to understand its benefits and limits, and to validate the design and deployment choices. While some network slicing prototypes have been built for the radio access networks (RANs), leveraging on the wide availability of radio hardware and open source software, there is currently no open source suite for end-to-end network slicing available to the research community. In this paper we fill this gap by developing an end-to-end network slicing protocol stack,
POSENS, which relies on a slice-aware shared RAN solution.
We design the required algorithms and protocols, and provide
a full implementation leveraging on state-of-the-art software components.We validate the effectiveness of POSENS in achieving tenant isolation and network slices customization, showing that no price in performance is paid to this end. We believe that our tool will prove very useful to researchers and practitioners working on this novel architectural paradigm.pu
Sharing renewable energy in a network sharing context
Get PDFThis paper studies the performance gains resulting from the sharing of energy and network resources in the case of co-located base stations of different mobile network operators, powered by photovoltaic panels, and equipped with energy storage. Three configurations are considered for base station cooperation. The first one assumes two non-cooperating base stations, each one exploiting its own power system and serving its own customers, hence with no sharing. The second considers a shared power system, but no cooperation in customer service. The third looks at cooperation in both energy production and service
provisioning, since only one base station handles all customers when traffic is low. Using an analytical modeling framework, we compute performance metrics for the three cases, and we show that significant gains are possible in the case of energy and network sharing.TRUEpu
A Simple Model of MTC in Smart Factories
Get PDFIn this paper we develop a simple, yet accurate, performance model to understand if and how evolutions of traditional cellular network protocols can be exploited to allow large numbers of devices to gain control of transmission resources
in smart factory radio access networks. The model results shed light on the applicability of evolved access procedures and help understand how many devices can be served per base station. In addition, considering the simultaneous presence of different traffic classes, we investigate the effectiveness of prioritised access, exploiting access class barring techniques. Our model shows that, even with the sub-millisecond time slots foreseen in LTE Advanced Pro and 5G, a base station can accommodate at most few thousand devices to guarantee access latencies below 100 ms with high transmission success probabilities. This calls for a rethinking of wireless access strategies to avoid ultra-dense cell deployments within smart factory infrastructures.TRUEpu