IMDEA Networks Institute Digital Repository
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The path towards a cloud-aware mobile network protocol stack
Get PDFWe are currently observing the softwarization of communication networks, where network functions are translated from monolithic pieces of equipment to programs running over a shared pool of computational, storage, and communication resources. While it is clear that almost any softwarization improves flexibility (e.g., the ability to instantiate more servers to cope with increasing traffic demand), in this paper we advocate for a complete re-design of the communications protocol stack, instead of a mere translation of hardware functions into software. We discuss two drivers for this cloud-aware re- design: (i) relaxing the tight interactions between functions, and (ii) supporting a graceful degradation of the service when resources become scarce. The potential benefits of this re-design are illustrated with the numerical evaluation of one use case.pu
Location-aware MAC Scheduling in Industrial-like Environment
Get PDFWe consider an environment strongly affected by the presence of metallic objects, that can be considered representative
of an indoor industrial environment with metal obstacles. This scenario is a very harsh environment where radio communication has notorious difficulties, as metallic objects create a strong blockage component and surfaces are highly reflective. In this environment, we investigate how to dynamically allocate MAC resources in time to static and mobile users based on context awareness extracted from a legacy WiFi positioning system. In order to address this problem, we integrate our WiFi ranging and positioning system in the WiSHFUL architecture and then define a hypothesis test to declare if the link is in line-of-sight (LOS) or non-line-of-sight (NLOS) based on angular information derived from ranging and position information. We show that context information can help increase the
network throughput in the above industrial-like scenario.TRUEpu
Demo: Channel Estimation and Custom Beamforming on the 60 GHz TP-Link Talon AD7200 Router
Get PDFCurrent IEEE 802.11ad millimeter-wave consumer devices use phased antenna arrays with a fixed set of pre-defined beam patterns. Such an approach has the advantage of being very low complexity and easy to implement. However, custom beam patterns adapted to the current channel can provide much better performance than generic pre-defined patterns.
In this demo, we show how to measure channel state information and modify beam patterns on the TP-Link Talon AD7200 router operating in the 60 GHz band. This allows to generate custom beam patterns with arbitrary shape, as well as beam patterns that maximize the signal strength of a link given the current channel. Our demo allows users to select custom beam patterns and visualizes the beam pattern in use. It is also possible to compare the custom patterns to the pre-defined beam patterns of the router and measure the performance in terms of throughput and signal strength.TRUEpu
Adaptive densification of mobile networks: Exploring correlations in vehicular and telecom traffic
Get PDFIn this paper we use real data to investigate the correlation in time and space between vehicular traffic and telecom traffic in cellular networks. The analysis of such a correlation is critical to assess the feasibility of cellular network architectures where densification is achieved with small-cell mobile base stations carried by vehicles. This is an attractive possibility for the provisioning of on-demand capacity through temporary dense small cell deployments where and when needed. Our results indicate that vehicular traffic at penetration rates expected for small-cell-carrying vehicles is much more bursty than telecom traffic. Yet, some correlations between the two emerge, even when considering an entire large metropolitan area. More importantly, correlations tend to be stronger in densely urbanized areas and during high-demand time periods, i.e., where and when radio access densification is most needed. Overall, our results indicate small-cell base stations carried by vehicles as a promising and cost-effective approach to dynamic provisioning of capacity in future-generation cellular networks.TRUEpu
Electrosense: Open and Big Spectrum Data
Get PDFWhile radio spectrum allocation is well regulated, there is little knowledge about its actual utilization over time and space. This limitation hinders taking effective actions in various applications including cognitive radios, electrosmog monitoring, and law enforcement. We introduce Electrosense, an initiative that seeks a more efficient, safe and reliable monitoring of the electromagnetic space by improving the accessibility of spectrum data for the general public. A collaborative spectrum monitoring network is designed that monitors the spectrum at large scale with low-cost spectrum sensing nodes. The large set of data is stored and processed in a big data architecture and provided back to the community with an open spectrum data as a service model, that allows users to build diverse and novel applications with different requirements. We illustrate useful usage scenarios of the Electrosense data.pu
Living and Fluid Networks: The way ahead?
Get PDFThe Internet is arguably the most complex infrastructure created by humankind. It is constantly and rapidly evolving to satisfy increasingly important and diverse requirements. Its underlying network infrastructure is experiencing a mutation from a transport-only, data-less, dumb infrastructure to a multifaceted and distributed system mimicking a living being and consisting of a stratum of fluidified networking and computing resources, dynamically organized and managed by more and more intelligent and autonomous algorithms, which generate and exploit increasing quantities of data, and provide customized services and applications alike everywhere. In this position paper, after a very brief historical excursus of how networks have evolved so far, we postulate that the recent advances in terms of networking technologies and their programmability improvements may provide the foundation of a future Internet where not only netputing (i.e., networking and in-network processing) services will be deployed on the fly, but even the protocols themselves that rule the Internet's operation will be dynamically adapted to the context and the needs of services and applications. Data and intelligent algorithms will be used not only to deliver personalized applications, but also to better operate the network itself. This also means that applications will be more deeply rooted within the network, so as to provide adaptive features, tailored to user needs, capable to better exploit network-generated data and functionality and to be (dynamically) instantiated (close to) where they are needed. The network will become even more pervasive and more integrated, further absorbing residual conceptual differences, e.g., between cellular/mobile and wired/core sections. Unlike for early attempts made, e.g., by active networking in the 90’ies, the time has probably now come for such a revolution.pu
Network Slices for Vertical Industries
Get PDFNetwork Slicing allows to simultaneously support the specific needs of vertical industries with a diverse range of networking and computing requirements. Network Functions Virtualization (NFV) has been defined to deploy multiple network services on a common infrastructure. We extend the NFV concept to vertical services, i.e. services implemented on top of network services and providing the applications of the verticals. We present a component of the 5G-Transformer system, named vertical slicer, which acts as the interface to verticals. The vertical slicer has two main functionalities: allowing verticals to define vertical services based on a set of service blueprints and arbitrating among several vertical services in case of resource shortage.TRUEpu
Fast and Infuriating: Performance and Pitfalls of 60 GHz WLANs Based on Consumer-Grade Hardware
Get PDFWireless networks operating in the 60 GHz band have the potential to provide very high throughput but face a number of challenges (e.g., high attenuation, beam training, and coping with mobility) which are widely accepted but often not well understood in practice. Understanding these challenges, and especially their actual impact on consumer-grade hardware is fundamental to fully exploit the high physical layer rates in the 60 GHz band. To this end, we perform an extensive measurement campaign using two commercial off-the-shelf 60 GHz routers in practical real-world environments. Our study is centered around two fundamental adaptation mechanisms in 60 GHz networks—beam training and rate control—whose interactions are key for performance. Understanding these interactions allows us to revisit a range of issues and provide much deeper insights into the reasons for specific performance compared to prior work on performance characterization. Further, our study goes beyond basic link characterization and explores for the first time practical considerations such as coverage and access point deployment. While some of our observations are expected, we also obtain highly surprising insights that challenge the prevailing wisdom in the community.TRUEpu
ATMoN: Adapting the “Temporality” in Large-Scale Dynamic Networks
Get PDFWith the widespread adoption of dynamic networks modeled as temporal graphs to study fast evolving interactions, attention is needed to provide graph metrics in time and at scale. In this paper, we introduce ATMoN, an open-source library developed to computationally offload graph processing engines and ease the communication overhead in monitored networks over an unprecedented wealth of data. This is achieved, by efficiently adapting, in place and inexpensively, the temporal granularity at which graph metrics are computed based on runtime knowledge captured by a low-cost probabilistic learning model capable of approximating both the metric stream evolution and the runtime volatility of the graph topology structure. After a thorough evaluation study with real-world data from mobile, face-to-face and vehicular networks, results show that ATMoN is able to reduce the computation overhead by at least 76%, data volume by 60%, overall cloud costs by at least 54%, while always maintaining accuracy above 88%.TRUEpu