During the last decade, the exponential growth of mobile devices and wireless services created a huge demand for radio frequency-based technologies. Meanwhile, the lighting industry has been ...revolutionized due to the popularization of LED light bulbs, which are more economical and efficient. In that context, visible light communication (VLC) is a disruptive technology based on LEDs that offers a free spectrum and high data rate, which can potentially serve as a complementary technology to the current radio frequency standards. In this paper, we present a comprehensive state-of-the-art survey of VLC, as well as the main concepts and challenges related to this emergent area. We overview VLC technology, from its physical aspects and communication architecture to its main applications and research challenges. Finally, we present the main research platforms available today, along with a deep analysis of the system design and future directions in the field.
NanoRouter: A Quantum-dot Cellular Automata Design Sardinha, Luiz H. B.; Costa, Artur M. M.; Neto, Omar P. Vilela ...
IEEE journal on selected areas in communications,
2013-December, 2013-12-00, 20131201, Letnik:
31, Številka:
12
Journal Article
Recenzirano
We present NanoRouter, a new router architecture implemented as a quantum-dot cellular automata (QCA). A router is a key component in the Internet core. It allows packets to be transferred in the ...Internet. QCA is a promising nanoscale technology where components have nano size, ultra-low power consumption and could have a clock rate on the terahertz range. In a bottom-up approach, we first describe the building blocks that compose NanoRouter such as crossbar, demux and parallel-to-serial converter and then describe the full architecture. We demonstrate the functionality, test and validate the proposed architecture and provided performance evaluations of NanoRouter. This new router architecture can increase the speed of the Internet core.
Fast Packet Processing with eBPF and XDP Vieira, Marcos A. M.; Castanho, Matheus S.; Pacífico, Racyus D. G. ...
ACM computing surveys,
02/2020, Letnik:
53, Številka:
1
Journal Article
Recenzirano
Extended Berkeley Packet Filter (eBPF) is an instruction set and an execution environment inside the Linux kernel. It enables modification, interaction, and kernel programmability at runtime. eBPF ...can be used to program the eXpress Data Path (XDP), a kernel network layer that processes packets closer to the NIC for fast packet processing. Developers can write programs in C or P4 languages and then compile to eBPF instructions, which can be processed by the kernel or by programmable devices (e.g., SmartNICs). Since its introduction in 2014, eBPF has been rapidly adopted by major companies such as Facebook, Cloudflare, and Netronome. Use cases include network monitoring, network traffic manipulation, load balancing, and system profiling. This work aims to present eBPF to an inexpert audience, covering the main theoretical and fundamental aspects of eBPF and XDP, as well as introducing the reader to simple examples to give insight into the general operation and use of both technologies.
A Sensor Equipped Aquatic (SEA) swarm is a sensor cloud that drifts with water currents and enables 4-D (space and time) monitoring of local underwater events such as contaminants, marine life, and ...intruders. The swarm is escorted on the surface by drifting sonobuoys that collect data from the underwater sensors via acoustic modems and report it in real time via radio to a monitoring center. The goal of this study is to design an efficient anycast routing algorithm for reliable underwater sensor event reporting to any surface sonobuoy. Major challenges are the ocean current and limited resources (bandwidth and energy). In this paper, these challenges are addressed, and HydroCast, which is a hydraulic-pressure-based anycast routing protocol that exploits the measured pressure levels to route data to the surface sonobuoys, is proposed. This paper makes the following contributions: a novel opportunistic routing mechanism to select the subset of forwarders that maximizes the greedy progress yet limits cochannel interference and an efficient underwater dead end recovery method that outperforms the recently proposed approaches. The proposed routing protocols are validated through extensive simulations.
Underwater Wireless Sensor Networks Coutinho, Rodolfo W. L.; Boukerche, Azzedine; Vieira, Luiz F. M. ...
ACM computing surveys,
01/2019, Letnik:
51, Številka:
1
Journal Article
Recenzirano
Underwater wireless sensor networks (UWSNs) will pave the way for a new era of underwater monitoring and actuation applications. The envisioned landscape of UWSN applications will help us learn more ...about our oceans, as well as about what lies beneath them. They are expected to change the current reality where no more than 5% of the volume of the oceans has been observed by humans. However, to enable large deployments of UWSNs, networking solutions toward efficient and reliable underwater data collection need to be investigated and proposed. In this context, the use of topology control algorithms for a suitable, autonomous, and on-the-fly organization of the UWSN topology might mitigate the undesired effects of underwater wireless communications and consequently improve the performance of networking services and protocols designed for UWSNs. This article presents and discusses the intrinsic properties, potentials, and current research challenges of topology control in underwater sensor networks. We propose to classify topology control algorithms based on the principal methodology used to change the network topology. They can be categorized in three major groups: power control, wireless interface mode management, and mobility assisted–based techniques. Using the proposed classification, we survey the current state of the art and present an in-depth discussion of topology control solutions designed for UWSNs.
Current implementations of Internet systems are very hard to be upgraded. The ossification of existing standards restricts the development of more advanced communication systems. New research ...initiatives, such as virtualization, software-defined radios, and software-defined networks, allow more flexibility for networks. However, until now, those initiatives have been developed individually. We advocate that the convergence of these overlying and complementary technologies can expand the amount of programmability on the network and support different innovative applications. Hence, this paper surveys the most recent research initiatives on programmable networks. We characterize programmable networks, where programmable devices execute specific code, and the network is separated into three planes: data, control, and management planes. We discuss the modern programmable network architectures, emphasizing their research issues, and, when possible, highlight their practical implementations. We survey the wireless and wired elements on the programmable data plane. Next, on the programmable control plane, we survey the divisor and controller elements. We conclude with final considerations, open issues and future challenges.
NFV and SDN enable flexibility and programmability at the data plane. In addition, offloading packet processing to a hardware saves processing resources to compute other workloads. However, ...fulfilling requirements such as high throughput and low latency with a flexible and programmable data plane is challenging. This paper introduces eBPFlow, a platform for seamlessly accelerating network computation. It builds upon eBPF. eBPFlow combines flexibility and programmability in software with high performance using an FPGA. We implemented our system on the NetFPGA SUME, performing tests on a physical testbed. We built a range of NFs. Our results show that the eBPFlow supports offloading of NFs with throughput at the line rate, latency between <inline-formula> <tex-math notation="LaTeX">20~\mu \text{s} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">40~\mu \text{s} </tex-math></inline-formula>, communication with host, and consumption of 22 W. Moreover, eBPFlow processes 12.05 Mpps more than the kernel. eBPFlow has a throughput of 2.59 Gbps higher than the hXDP, a system similar to eBPFlow.
Dual-Radio platforms were proposed to improve the throughput of Wireless Sensor Network applications while conserving energy efficiency. However, current dual-radio protocols do not use all the ...hardware available. We model this problem as the minimum disjoint parity paths problem. We present the design, implementation and evaluation of SplitPath, a distributed routing protocol that computes two vertex-disjoint paths with the same parity. Unlike previous work on multipath routing, SplitPath is the first protocol to use multiple paths in dual-radio WSNs to achieve maximum throughput. The protocol was evaluated with experiments in the physical world. We compare our proposal with FastForward, the state-of-the-art protocol for dual-radio. Our approach improved the throughput by 60%, and achieved 96% of the maximum theoretical limit.
Underwater sensor networks are used to collect data from aquatic environments. Nodes from these networks usually communicate via acoustic or optical transmissions due to the poor performance of ...radiofrequency communication in these environments. Acoustic transmissions achieve longer distances than optical ones, but also consume more energy and have lower bandwidth. Underwater optical-acoustic sensor networks (UOASNs) combine both types of communication to explore the best of each one. In this paper, we propose CAPTAIN, an algorithm to perform data collection with data aggregation in UOASNs. CAPTAIN divides the network into clusters, builds a routing tree, and uses data aggregation to deliver all data collected to the sink node. Experiments showed that, compared to the shortest path algorithm, CAPTAIN led to lower network energy consumption, especially in denser networks, where it was able to consume, on average, up to 73% less. CAPTAIN could also achieve lower average latencies (up to almost 83% lower) and higher rates of data collected per hour by the sink node using fewer acoustic transmissions in clustered networks.
Aiming to increase throughput in Wireless Networks, such as in Wireless Sensor Network and the Internet of Things, platforms emerged in which devices have two radios, and also data transfer protocols ...that prioritize maximum throughput and energy efficiency, using two different paths simultaneously. The usage of dual radios allowed simultaneous transmissions between wireless devices, which, besides increasing network throughput, can also improve network stability, delivery rate, transmission cost, and energy consumption per transmitted byte. However, one path may be much longer than the other, causing high latency. First, in this work, we present the problem formulation to find two disjoint paths with the same parity size for platforms with two heterogeneous radios to reach the network maximum flow, while also minimizing the longest path, which reduces latency. Second, we show that the problem is NP-Complete. Next, we present a solution based on integer linear programming. Moreover, we tested the solution on almost 5,700 instances obtained from an actual testbed and the results show a reduction in latency while maintaining the high throughput.
