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Multi-beam power allocation for mmwave communications under random blockage
Get PDFMilimeter-wave links can provide GBit/s data rates but are highly susceptible to blockage. In case a direct line of sight communication path becomes blocked, communication via a reflected path may allow to maintain connectivity. A common approach is to switch to such an alternative path whenever the first path becomes blocked. However, this requires detecting the blockage and then reconfiguring the transceiver to use the new path which incurs latency. For traffic with strict latency or reliability requirements, or in highly dynamic environments where path switching would be frequent, using both paths concurrently can be more beneficial. In this paper, we consider using multiple paths and dividing the transmission power over those paths, instead of path switching. We propose an algorithm to allocate power among the different mmWave communication paths to overcome link blockage under randomly distributed obstacles. The power allocation algorithm is based on analysis of the blockage probabilities of the direct and reflected paths using geometric probability, to statistically maximize the overall capacity of the path between two nodes. We evaluate the performance of the proposed algorithm via simulation for various wireless environments.TRUEpu
A distributed and quiescent max-min fair algorithm for network congestion control
Get PDFGiven the higher demands in network bandwidth and speed that the Internet will have to meet in the near future, it is crucial to research and design intelligent and proactive congestion control and avoidance mechanisms able to anticipate decisions before the congestion problems appear. Nowadays, congestion control mechanisms in the Internet are based on TCP, a transport protocol that is totally reactive and cannot adapt to network variability because its convergence speed to the optimal values is slow. In this context, we propose to investigate new congestion control mechanisms that (a)
explicitly compute the optimal sessions' sending rates independently of congestion signals (i.e., proactive mechanisms) and (b) take anticipatory decisions (e.g., using forecasting or prediction techniques) in order to avoid the appearance of congestion problems.
In this paper we present B-Neck, a distributed optimization algorithm that can be used as the basic building block for the new generation of proactive and anticipatory congestion control protocols. B-Neck computes proactively the optimal sessions' sending rates independently of congestion signals. B-Neck applies max-min fairness as optimization criterion, since it is very often used in traffic engineering as a way of fairly distributing a network capacity among a set of sessions. B-Neck iterates rapidly until converging to the optimal solution and is also quiescent. The fact that B-Neck
is quiescent means that it stops creating traffic when it has converged to the max-min rates, as long as there are no changes in the sessions. B-Neck reacts to variations in the environment, and so, changes in the sessions (e.g., arrivals and departures) reactivate the algorithm, and eventually the new sending rates are found and notified. To the best of our knowledge, B-Neck is the first distributed algorithm that maintains the computed max-min fair rates without the need of continuous traffic injection, which can be advantageous, e.g., in energy efficiency scenarios.
This paper proposes as novelty two theoretical contributions jointly with an in-depth experimental evaluation of the B-Neck optimization algorithm. First, it is formally proven that B-Neck is correct, and second, an upper bound for its convergence time is obtained. In addition, extensive simulations were conducted to validate the theoretical results and compare B-Neck with the most representative competitors. These experiments show that B-Neck behaves nicely in the presence of sessions arriving and departing, and its convergence time is in the same range as that of the fastest (non-quiescent) distributed max-min fair algorithms. These properties encourage to utilize B-Neck as the basic building block of proactive and anticipatory congestion control protocols.pu
Resource Orchestration of 5G Transport Networks for Vertical Industries
No full textThe future 5G transport networks are envisioned to support a variety of vertical services through network slicing and efficient orchestration over multiple administrative domains. In this paper, we propose an orchestrator architecture to support vertical services to meet their diverse resource and service requirements. We then present a system model for resource orchestration of transport networks as well as low-complexity algorithms that aim at minimizing service deployment cost and/or service latency. Importantly, the proposed model can work with any level of abstractions exposed by the underlying network or the federated domains depending on their representation of resources.TRUEpu
Adaptable and Automated Small UAV Deployments via Virtualization
Get PDFIn this paper, we present a practical solution to support the adaptable and automated deployment of applications of Small Unmanned Aerial Vehicles (SUAVs). Our solution is based on virtualization technologies, and considers SUAVs as programmable network platforms capable of executing virtual functions and services, which may be dynamically selected according to the requirements specified by the operator of the aerial vehicles. This way, SUAVs can be flexibly and rapidly adapted to different missions with heterogeneous objectives. The design of our solution is based on Network Function Virtualization (NFV) technologies, developed under the umbrella of the fifth generation of mobile networks (5G), as well as on existing Internet protocol standards, including flying ad hoc network routing protocols. We implemented a functional prototype of our solution using well-known open source technologies, and we demonstrated its practical feasibility with the execution of an IP telephony service. This service was implemented as a set of virtualized network functions, which were automatically deployed and interconnected over an infrastructure of SUAVs, being the telephony service tested with real voice-over-IP terminals.pu
Fine-grained LTE Radio Link Estimation for Mobile Phones
Get PDFRecently, spectrum optimization solutions require mobile phones to obtain precise, accurate and fine-grained estimates of the radio link data rate. In particular, the effectiveness of anticipatory schemes depends on the granularity of these measurements. In this paper we use a reliable LTE control channel sniffer (OWL) to extensively compare mobile phone measurements against exact LTE radio link data rates. We also provide a detailed study of latencies measured on mobile phones, the sniffer, and a server to which the phone is connected. In this study, we show that mobile phones can accurately (if slightly biased) estimate the physical radio link data rate. We highlight the differences among measurements obtained using different mobile phones, communication technologies and protocols. We also provide detailed instructions on how to replicate our measurements and describe alternative measurement setups and their tradeoffs.pu
Panel: The impact of 5G in the Tourism Industry
No full textPanel Organizer: Arturo Azcorra
Panel Moderator: Jaume Monserrat (TURISTEC)
Panel Members: Arturo Azcorra (IMDEA Networks Institute), Manuel Lorenzo (Ericsson), Luis Ignacio Vicente (Telefonica)FALSEpu
An Analysis of Pre-installed Android Software
Get PDFThanks to the openness of the Android ecosystem, mobile device vendors can build and sell smart phones and other mobile devices using their own custom versions of Android. Most of these custom versions deviate significantly from Google’s official Android Open Source Project (AOSP): in addition to various visual and functional changes to the base OS, vendors add proprietary applications (apps hereafter) to their firmware, and sometimes even add custom (often unknown) certificates to the system’s root certificate store. In fact, recent anecdotal evidence has revealed that pre-installed apps can put, intentionally or not, user’s privacy and security at risk. This is especially concerning for lesser-known brands producing lower-end devices for whom preserving user privacy might not be high on the priority list. In this extended abstract, we present our methodology to explore the complex and diverse ecosystem of Android pre-installed apps as well as our preliminary results.TRUEpu
Coming of Age: A Longitudinal Study of TLS Deployment
Get PDFhttps://doi.org/10.1145/3278532.3278568The Transport Layer Security (TLS) protocol is the de-facto standard for encrypted communication on the Internet. However, it has been plagued by a number of different attacks and security issues over the last years. Addressing these attacks requires changes to the protocol, to server- or client-software, or to all of them. In this paper we conduct the first large-scale longitudinal study examining the evolution of the TLS ecosystem over the last six years. We place a special focus on the ecosystem’s evolution in response to high-profile attacks.
For our analysis, we use a passive measurement dataset with more than 319.3B connections since February 2012, and an active dataset that contains TLS and SSL scans of the entire IPv4 address space since August 2015. To identify the evolution of specific clients we also create the—to our knowledge—largest TLS client fingerprint database to date, consisting of 1,684 fingerprints. We observe that the ecosystem has shifted significantly since 2012, with major changes in which cipher suites and TLS extensions are offered by clients and accepted by servers having taken place.
Where possible, we correlate these with the timing of specific attacks on TLS. At the same time, our results show that while clients, especially browsers, are quick to adopt new algorithms, they are also slow to drop support for older ones. We also encounter significant amounts of client software that probably unwittingly offer unsafe ciphers. We discuss these findings in the context of long tail effects in the TLS ecosystem.TRUEpu
