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.
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.
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.
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.
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.
The novel Underwater Wireless Sensor Network (UWSN) can contribute to monitor and explore aquatic environments. But, communicating in these environments is still hard and has many challenges. For ...example, optical and electromagnetic waves deteriorate from high-attenuation. Moreover, acoustic communication has a large packet error rate and low throughput. A large number of solutions to improve aquatic communication refers to routing protocols, medium access control protocols, and designing acoustic modems. Cooperative communication explores the broadcast nature of wireless transmission and enhances its performance. However, cooperative communication has not been fully explored in UWSNs. In this work, we present COPPER, a Cooperative Protocol for Pervasive Underwater Acoustic Networks. COPPER considers LLC and MAC sub-layers and operates synchronously or asynchronously over Time Division Multiple Access using a selective repeat ARQ scheme. COPPER exploits the broadcast nature of wireless communication and, sensor nodes that are idle can operate as a relay, enhancing communication by space diversity. Simulation results show that COPPER improves network performance. For example, the network goodput improves by 17% and the packet error rate decreases by 65%.
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.
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.
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.
High latency, low transmission rate and the presence of limited computational devices are characteristics present in scenarios of underwater communications. Despite the existence of concrete works on ...underwater wireless sensor networks (UWSNs), there is a gap in the interoperability of these networks and the traditional Internet networks. Indeed, communication solutions, routing algorithms and even data acquisition and analysis solutions are specifically designed to a given context or technology. In this work, we propose to turn this scenario into a ubiquitous scenario, similar to the Internet of Things, creating the Internet of Underwater Things (IoUT). More precisely, we present the Water Ping, a suppression proposal for ICMP and ICMPv6 protocol messages which will serve as a building block of the IoUT. The protocol we propose allows underwater devices to send/receive ping messages, which is one of the most widely know Internet application. Our results evidence that –now– underwater network devices can now be remotely effectively monitored through the Internet. Moreover, the suppression mechanism we propose can significantly reduce message sizes, which in turn lower the energy consumption by almost 94%.
