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Survey of Performance Acceleration Techniques for Network Function Virtualization
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| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 4) |
| Halaman | : | 746-764 |
| Abstrak | : | The ongoing network softwarization trend holds the promise to revolutionize network infrastructures by making them more flexible, reconfigurable, portable, and more adaptive than ever. Still, the migration from hard-coded/hard-wired network functions toward their software-programmable counterparts comes along with the need for tailored optimizations and acceleration techniques so as to avoid or at least mitigate the throughput/latency performance degradation with respect to fixed function network elements. The contribution of this paper is twofold. First, we provide a comprehensive overview of the host-based network function virtualization (NFV) ecosystem, covering a broad range of techniques, from low-level hardware acceleration and bump-in-the-wire offloading approaches to high-level software acceleration solutions, including the virtualization technique itself. Second, we derive guidelines regarding the design, development, and operation of NFV-based deployments that meet the flexibility and scalability requirements of modern communication networks. |
The Trolley, The Bull Bar, and Why Engineers Should Care About The Ethics of Autonomous Cars [point of view]
| Pengarang | : | Jean-François Bonnefon |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 3) |
| Halaman | : | 502-504 |
| Abstrak | : | Everyone agrees that autonomous cars ought to save lives. Even if the cars do not live up to the most optimistic estimates of eliminating 90% of traffic fatalities [1], eliminating at least some traffic fatalities is one of the key promises of automated driving. Indeed, the first two principles of the German Ethics Code for Automated and Connected Vehicles lead with this goal as a normative imperative [2].The primary purpose of partly and fully automated transport systems is to improve safety for all road users. The licensing of automated systems is not justifiable unless it promises to produce at least a diminution in harm compared with human driving [...]. |
Scaling Millimeter-Wave Networks to Dense Deployments and Dynamic Environments
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 4) |
| Halaman | : | 732-745 |
| Abstrak | : | Millimeter-wave (mmWave) communications have emerged as one of the most promising options to vastly increase wireless data rates due to the high bandwidth they offer. Given the high path loss at mmWave frequencies, such systems require directional antennas to achieve a good communication range. Thus, the communicating devices need to align the beam directions of their mmWave antennas. Due to the high penetration loss, the paths between the antennas also need to be free of blocking obstacles. This makes an efficient and reliable operation of mmWave networks in dynamic environments very challenging. At the same time, the directionality reduces interference and allows to scale these networks to much higher access point and device densities. In this paper, we discuss the above-mentioned challenges and present techniques that allow mmWave networks to scale to high-density deployments, to adapt to dynamic and mobile environments, and to consistently achieve high data rates. This includes learning the environment to find different propagation paths, reacting timely to channel impairments such as blockage, and integrating mmWave networks with networks operating at a lower frequency for robustness. A key ingredient to enable these forms of adaptivity is the use of location information. Such mechanisms then turn a collection of very-high-speed but brittle mmWave links into an efficient, low-latency, and reliable network |
Adaptable and Data-Driven Softwarized Networks: Review, Opportunities, and Challenges
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 4) |
| Halaman | : | 711-731 |
| Abstrak | : | Communication networks are the key enabling technology for our digital society. In order to sustain their critical services in the future, communication networks need to flexibly accommodate new requirements and changing contexts due to emerging diverse applications. In contrast to traditional networking technologies, software-oriented networking concepts, such as software-defined networking (SDN) and network function virtualization (NFV), provide ample opportunities for highly flexible network operations, enabling fast and simple adaptation of network resources and flows. This paper identifies the opportunities and challenges of adaptable softwarized networks and introduces a conceptual framework for adaptations in softwarized networks. We first explain how softwarized networks contribute to network adaptability through the functional primitives observation, composition, and control. We review the wide range of options for fine-granular observations as well as fine-granular composition and control provided by SDN and NFV. The multitude of fine-granular “tuning knobs” in adaptable softwarized networks complicates the decision making, which is the main focus of this paper. We propose to enhance the functional primitives observation, composition, and control with data-driven decision making, e.g., machine learning modules, resulting in deep observation, composition, and control. The data-driven decision making modules can learn and react to changes in the environment, e.g., new flow demands, so as to support meaningful decision making for adaptation in softwarized networks. Finally, we make the case for employing the concept of empowerment to realize truly “self-driving” networks. |
Misconceptions Arising From the Infinite Solenoid Magnetic Field Formula
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 213-215 |
| Abstrak | : | Many high school and first-year university courses include discussion of the magnetic effect of currents. Frequently discussed textbook examples include long, straight wires, circular current loops, and solenoids, partly because these examples are tractable mathematically. The solenoid naturally leads to discussion on magnetic materials since it is readily demonstrated that a paramagnetic core significantly boosts the strength of an electromagnet. However, magnetic effects of solid and even liquid materials are subtle and confusing and the mathematics is not straightforward. This leads to confusion amongst students (and their teachers), which, when taken to more advanced study, leads to significant misconceptions about the nature of magnetic properties and fields. These misconceptions can become problematic when practical (rather than stereotyped) magnetic design and analysis is required such as for transformers, magnetic recording materials, geomagnetic sensors, or biological stimulators to name a few. In this article, I highlight examples of this confusion, in particular the failure in realistic situations of the well-quoted formula for an infinite solenoid with a paramagnetic core, and the physical interpretation of the relative permeability of a material, µr. |
Energy Conservation in a Motor-Driven Generator
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 210-212 |
| Abstrak | : | An electric motor converts electrical energy into mechanical work and an electric generator converts mechanical work into electrical energy. The symmetry between the motor and generator naturally leads to questions about creating a perpetual motion machine. The allure of this question has inspired textbook problems, physics education articles, and award-winning physics demonstrations. It is commonly taught that spinning a generator faster produces a larger electromotive force (EMF), because the generator’s instantaneous EMF is proportional to the angular rate of rotation. When making this point in class, students will often ask about an interesting thought experiment, which is depicted in Fig. 1. The student question is as follows: “If an electric motor is connected via a system of gears to an electric generator, so that the generator spins faster than the motor, then does the generator’s output power PG exceed the motor’s input power PM ?” |
NGSS Engineering Practices in Physics Instruction: Building a Night Light
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 206-209 |
| Abstrak | : | Many physics teachers have experienced the challenges of implementing the Next Generation Science Standards (NGSS) in their high school curricula. These standards, based upon the Framework for K-12 Science Education, were intended to shift science instruction towards an interdisciplinary focus on three-dimensional learning, phenomena anchored explorations, and developing solutions for technological problems. The present paper describes a collaboration between electrical and computer engineers and physics educators, whereby a physics unit was created to embed engineering practices in the design of a night light. Although the project also incorporates aspects of crosscutting concepts and disciplinary core ideas, we focused on engineering practices since more educational resources are needed that illustrate this aspect of NGSS-aligned teaching and learning. The unit was piloted with over 1500 high school students in an informal outreach program, as well as professional development workshops for 100 secondary science teachers, with the intent that teachers would incorporate this and other engineering projects in their physical science classrooms. |
Scalable Personalized IoT Networks
| Pengarang | : | Amr El-Mougy,Bruce I. Davidson |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 4) |
| Halaman | : | 695-710 |
| Abstrak | : | The Internet of Things (IoT) has enabled unprecedented interactions with our physical world, with the aim to deliver a wide range of customizable services in many domains. With recent advancements in IoT technology, users are increasingly expecting these services to be intelligent and context aware. Nevertheless, there is still no framework capable of delivering personalized IoT services on a large scale. For such a framework to be conceived, it is likely that technologies from many domains have to be utilized. This paper examines the readiness of the leading state-of-the-art technologies in several key fields for realizing the goal of a truly scalable and personalized IoT experience. We discuss the important requirements and challenges for realizing this goal. Then, we identify the major approaches that can contribute to this goal and categorize them into: technologies for adaptive personalized sensing, scalable solutions for user-centric networking, and intelligence techniques that leverage context awareness and adaptability at the application and system levels. In the first category, our discussion centers around virtualization and reprogrammability at the sensing layer. In the second category, we investigate the readiness of Fog computing and information-centric networking to develop scalable personalized IoT infrastructures. These approaches were chosen for their combined ability to match dynamic user requirements with available system resources, while guaranteeing overall efficient utilization. Finally, in the third category, we examine context awareness, reasoning, and machine learning techniques as well as semantic technologies for realizing proactive and adaptive intelligent IoT systems and applications. This paper offers a focused discussion of the key topics that drive the research in the important and timely topic of scalable and personalized IoT networks. |
An Arduino-Based Experiment Designed to Investigate Gas Pressure
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 202-204 |
| Abstrak | : | This study aims to showcase an experiment for introductory physics students that quantitatively describes the relationship between gas pressure, volume, and temperature. For this purpose, an Arduino Uno Microcontroller and BMP180 pressure sensor are used. The BMP180 can also measure temperature, so another temperature sensor is not needed. Pressure-volume and pressure-temperature graphs are plotted with the experimental setup using cheap and easily accessible materials. It can be seen that the drawn graphs correspond well to the theory. It is hoped that this experimental setup can be used by teachers in STEM activities, especially for physics courses. |
Modeling of Aggregated IoT Traffic and Its Application to an IoT Cloud
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 4) |
| Halaman | : | 679-694 |
| Abstrak | : | As the Internet of Things (IoT) continues to gain traction in telecommunication networks, a very large number of devices are expected to be connected and used in the near future. In order to appropriately plan and dimension the network, as well as the back-end cloud systems and the resulting signaling load, traffic models are employed. These models are designed to accurately capture and predict the properties of IoT traffic in a concise manner. To achieve this, Poisson process approximations, based on the Palm–Khintchine theorem, have often been used in the past. Due to the scale (and the difference in scales in various IoT networks) of the modeled systems, the fidelity of this approximation is crucial, as, in practice, it is very challenging to accurately measure or simulate large-scale IoT deployments. The main goal of this paper is to understand the level of accuracy of the Poisson approximation model. To this end, we first survey both common IoT network properties and network scales as well as traffic types. Second, we explain and discuss the Palm–Khintiche theorem, how it is applied to the problem, and which inaccuracies can occur when using it. Based on this, we derive guidelines as to when a Poisson process can be assumed for aggregated periodic IoT traffic. Finally, we evaluate our approach in the context of an IoT cloud scaler use case. |