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5G Network Slicing: Part 1 – Concepts, Principales, and Architectures [Guest Editorial]
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JADE: Zero-Knowledge Device Localization and Environment Mapping for Millimeter Wave Systems
Get PDFDevice localization is a highly important functionality for a range of applications. It is particularly beneficial in mmWave networks, where it can be used to reduce the beam training overhead and anticipate handovers between access points. In this paper, we present JADE, an algorithm that estimates the location of a mobile user in an indoor space without any knowledge about the surrounding environment (floor plan, location of walls and presence of reflective surfaces) or about the location and number of access points available therein. JADE leverages the beam procedure used in pre-standard and commercial mmWave equipment to estimate the angle-of-arrival of multipath components of the signal sent by visible access points. This information is then employed to localize the mobile user, estimate the position of access points and finally form a map of the environment. No radar-like ranging operations are required for this. Our results demonstrate that JADE can localize a user with sub-meter accuracy in the broad majority of the cases, and that it even outperforms localization algorithms that require full knowledge of the environment and access point positions.TRUEpu
Full Reconfiguration of Underwater Acoustic Networks through Low-Level Physical Layer Access
Get PDFDOI: https://doi.org/10.475/123_4Underwater acoustic communications experiments often involve custom implementations of schemes and protocols for the physical and data link layers. However, most commercial modems focus on providing reliable or optimized communication links, rather than on allowing low-level reconfiguration or reprogramming of modulation and coding schemes. As a result, the physical layer is typically provided as a closed, non-reprogrammable black box, accessible by the user only through a specific interface.
While software-defined modems would be the ultimate solution to overcome this issue, having access to the symbols transmitted by the modems using a proprietary modulation format already opens up a number of research opportunities, e.g., aimed at the cross-layer design and optimization of channel coding schemes and communication protocols.
In this paper, we take the latter approach. We consider the commercial EvoLogics modem, driven by a custom firm\-ware version that bypasses the channel coding methods applied by the modem, and allows the user to set the transmit bit rate to any desired value within a given set. This makes it possible to evaluate different coding schemes in the presence of different bit rates. Our results show that the custom firmware offers sufficient flexibility to test different configurations of the coding schemes and bit rates, by providing direct access both to correctly decoded and to corrupted symbols, which can be separated at the receiver for further processing. In addition, we show that the DESERT Underwater framework can also leverage the same flexibility by employing low-level physical layer access in more complex networking experiments.TRUEpu
Opportunities and Challenges of Ad-based Measurements from the Edge of the Network
Get PDFFor many years, the research community, practitioners, and regulators have used myriad methods and tools to understand the complex structure and behavior of ISPs from the edge of the network. Unfortunately, the nature of these techniques forces the researcher to find a balance between ISP-coverage, user scale, and accuracy. In this paper we present AdTag, a network measurement paradigm that leverages the opportunistic nature of online targeted advertising to measure the Internet from the edge of the network. We discuss and formalize AdTag's design space---including technical, ethical, deployability and economic factors---and its potential to analyze a wide spectrum of Internet connectivity aspects from the browser. We run several experiments to demonstrate that AdTag can be tailored towards geographic and device-based user groups, finding also several challenges to be faced in order to maximize the number of samples. In a 7-day campaign, AdTag could access more than 20K ISPs at a global scale (185 countries) using millions of edge nodes.TRUEpu
MONROE: Measuring Mobile Broadband Networks in Europe
Get PDFMobile broadband (MBB) networks (e.g., 3G/4G) underpin numerous vital operations of the society and are arguably becoming the most important piece of the communications infrastructure. Given the importance of MBB net- works, there is a strong need for objective information about their performance, particularly, the quality experienced by the end user. Such information is valuable to operators, regulators and policy makers, consumers and society at large, businesses whose services depend on MBB networks, researchers and innovators. In this chapter, we introduce the MONROE1 measurement platform: An open access, European-scale, and flexible hardware-based platform for measurements and custom experimentation on operational MBB networks with WiFi connectivity. The platform consists of mobile and stationary nodes that are flexible and powerful enough to run most measurement and experiments tasks, including demanding applications like adaptive video streaming. Access to such a platform enables accurate, realistic and meaningful assessment of the performance of MBB networks by continuously monitoring these networks via active testing (e.g., delay test, web performance test, download speed test) and context metadata collection (e.g., connection mode, signal strength parameters). The multihoming feature of MONROE allows for the comparison of different networks under similar conditions as well as the exploration of new ways of aggregating providers to increase performance and robustness. In this chapter, we showcase the monitoring capabilities of the platform by analyzing preliminary performance measurement results. Considering that MONROE is open to external users, we further discuss a representative set of measurements and experiments to highlight the potential use cases of the platform. We argue that mobile measurements over operational networks, hence platforms such as MONROE, are crucial not only for characterizing and improving the user experience for services that are running on the current 3G/4G infrastructure, but also for providing feedback on the design of upcoming 5G technologies.TRUEpu
Multi-Path D2D Leads to Satisfaction
Get PDFDevice-to-Device (D2D) communications potentially allow users placed in a cell to establish direct connections among them using several connection modes. In this paper, we propose \textsl{Multi-Path D2D (MPD2D)}, a mathematical optimisation framework that accounts for the availability of D2D modes under flow demand requirements. MPD2D selects the combination of cellular and D2D links that fits better for boosting the network benefit. We consider the \textsl{Underlay} and \textsl{Overlay} as \textsl{Inband} D2D modes over cellular technology
(LTE) and the \textsl{Outband} D2D mode exploiting WLAN technology (WiFi). Throughput, energy consumption, interference, and flow requirements are managed in order to maximise a network utility function accounting for cell capacity and power efficiency. We also derive a user's satisfaction metric that accounts for the history of users within the cell. Integrating such a metric is lightweight yet very effective to drive towards almost complete fairness for the system over time. Our optimisation scheme is formulated as a Binary Non-Linear Program which results in very high performance in terms of throughput gain in comparison to other benchmarks for the \textsl{D2D mode selection problem}. Finally, we propose two effective heuristics whose performance and complexity we compare with optimal results and that largely outperform state of the art solutions.TRUEpu
Analytical Characterization of In-band and Out-band D2D Communications for Network Access
Get PDFCooperative short-range communication schemes provide powerful tools to solve interference and resource shortage problems in wireless access networks. With such schemes, a mobile node with excellent cellular connectivity can momentarily accept to relay traffic for its neighbors experiencing poor radio conditions and use Device-to-Device (D2D) communications to accomplish the task. This thesis provides a novel and comprehensive analytical framework that allows evaluating the effects of D2D communications in access networks in terms of spectrum and energy efficiency. The analysis covers the cases in which D2D communications use the same bandwidth of legacy cellular users (in-band D2D) or a different one (out-band D2D) and leverages on the characterization of underlying queueing systems and protocols to capture the complex intertwining of short-range and legacy WiFi and cellular communications.
The analysis also unveils how D2D affects the use and scope of other optimization techniques used for, e.g., interference coordination and fairness in resource distribution. Indeed, characterizing the performance of D2D-enabled wireless access networks plays an essential role in the optimization of system operation and, as a consequence, permits to assess the general applicability of D2D solutions. With such characterization, we were able to design several mechanisms that improve system capabilities. Specifically, we propose bandwidth resource management techniques for controlling interference when cellular users and D2D pairs share the same spectrum, we design advanced and energy-aware access selection mechanisms, we show how to adopt D2D communications in conjunction with interference coordination schemes to achieve high and fair throughputs, and we discuss on end-to-end fairness-beyond the use of access network resources-when D2D communications is adopted in C-RAN. The results reported in this thesis show that identifying performance bottlenecks is key to properly control network operation, and, interestingly, bottlenecks may not be represented just by wireless resources when end-to-end fairness is of concern.Telematics EngineeringUniversidad Carlos III de Madrid, Spainpu
Network slicing: Enabling Customization in 5G Mobile Networks Abstract
No full textThere is consensus among the relevant industry and standardization communities that a key element in 5G mobile networks will be network slicing. The idea is to allow the mobile infrastructure to be "sliced" into logical networks, where each slice is a collection of resources and functions that includes software modules running at different locations as well as the nodes' computational and communication resources. The intention is to tailor each slice to support a specific service, providing only what is necessary for the service while avoiding unnecessary overheads and complexity. This provides a basis for efficient infrastructure sharing among diverse entities, ranging from classical or virtual mobile network operators to new players that simply view connectivity as a service, where each of these entities may be running one or more slices. This talk will focus on the key enablers for network slicing and the research challenges involved in realizing this technology. Current standardization activities will be reviewed along with the contributions of major research projects, such as the H2020 5G-NORMA and 5G-MoNArch projects. A key problem underlying network slicing is enabling efficient sharing of mobile network resources. Various approaches considered in 3GPP will be analysed, ranging from per-reservation based schemes (where network slices reserve the required resources in advance) to others based on network shares (where resources are allocated based on pre-determined shares). The performance and behavior of the various approaches will be studied based on analytical tools including optimization, game theory and machine learning. Buildig on these analyses, we will provide some insights on the stability, peformance, optimality and level of customization enabled by the various approaches.TRUEpu
Orchestration of Network Services Across Multiple Operators: The 5G Exchange Prototype
Get PDFFuture 5G networks will rely on the coordinated allocation of compute, storage, and networking resources in order to meet the functional requirements of 5G services as well as guaranteeing efficient usage of the network infrastructure. However, the 5G service provisioning paradigm will also require a unified infrastructure service market that integrates multiple operators and technologies. The 5G Exchange (5GEx) project, building heavily on the Software-Defined Network (SDN) and the Network Function Virtualization (NFV) functionalities, tries to overcome this market and technology fragmentation by designing, implementing, and testing a multi-domain orchestrator (MdO) prototype for fast and automated Network Service (NS) provisioning over multiple-technologies and spanning across multiple operators. This paper presents a first implementation of the 5GEx MdO prototype obtained by extending existing open source software tools at the disposal of the 5GEx partners. The main functions of the 5GEx MdO prototype are showcased by demonstrating how it is possible to create and deploy NSs in the context of a Slice as a Service (SlaaS) use-case, based on a multi-operator scenario. The 5GEx MdO prototype performance is experimentally evaluated running validation tests within the 5GEx sandbox. The overall time required for the NS deployment has been evaluated considering NSs deployed across two operators.TRUEpu