Despite network monitoring and testing being critical for computer networks, current solutions are both extremely expensive and inflexible. Into this lacuna we launch the Open Source Network Tester (OSNT), a fully open-source traffic generator and capture system. Our prototype implementation on the NetFPGA-10G supports 4×10Gbps traffic generation across all packet sizes and traffic capture is supported up to 2×10Gbps with naïve host software. Our system implementation provides methods for scaling and coordinating multiple generator/capture systems and supports 6.25ns timestamp resolution with clock drift and phase coordination maintained by a GPS input. Additionally, our approach has demonstrated lower-cost than comparable commercial systems while achieving comparable levels of precision and accuracy; all within an open-source framework extensible with new features to support new applications, while permitting validation and review of the implementation.

This paper presents a practical approach to rapidly introducing new dataplane functionality into networks: End-hosts embed tiny programs into packets to actively query and manipulate a network's internal state. We show how this "tiny packet program" (TPP) interface gives end-hosts unprecedented visibility into network behavior, enabling them to work with the network to achieve a desired functionality. Our design leverages what each component does best: (a) switches forward and execute tiny packet programs (at most 5 instructions) in-band at line rate, and (b) end-hosts perform arbitrary (and easily updated) computation on network state. By implementing three different research proposals, we show that TPPs are useful. Using a hardware prototype on a NetFPGA, we show our design is feasible at a reasonable cost.

that the pathogenic species B. xylophilus and non-pathogenic related species B. mucronatus have very similar morphologies, 9 the operation staff has required specialized knowledge about the nematode morphology, and it is extremely difficult to distinguish the pathogenic species from non-pathogenic related species. In recent years, polymerase chain reaction (PCR)-based detection methods for nematodes have been developed, such as conventional 10 or real-time PCR. 11 Real-time PCR can offer an accurate diagnosis of B. xylophilus. However, complicated operation and relatively expensive equipment required during the PCR reaction limit it within a laboratory area. 12,13 Thus, a simple and rapid detection method is a very important research goal for the on-site detection of B. xylophilus.Herein, we proposed a simple and robust detection strategy of B. xylophilus using the strand exchange amplification (SEA) technique. 14 The SEA technique is identified as isothermal PCR, which only requires a pair of specific primers, and then utilizes successive natural strand "breathing" to unwound double-stranded DNA, rather than heat denaturation. 15 Thus, our strategy was expected to provide a novel nucleic acid amplification method for detecting pinewood nematode, which can be further applied to other target specific detection and electrochemical signal amplification strategy research. [16][17][18] 2019 Bursaphelenchus xylophilus (B. xylophilus) is one of the most important causal agents of infectious diseases in forest pathology. Obviously, the rapid detection of B. xylophilus is an urgent need for its prevention and cure. We have developed a detection method of B. xylophilus by strand exchange amplification (SEA). This method could detect 10 5 copies of genomic DNA of B. xylophilus, and it was sufficiently sensitive to detect a single nematode as short as 40 min. Moreover, because the amplification result could be visualized by the naked eyes, the only equipment required throughout the process was a simple isothermal block. Therefore, our method would be a potential for developing on-site detection of B. xylophilus to prevent and control its spread.

No abstract

Financial exchanges have begun a move from on-premise and custom-engineered datacenters to the public cloud, accelerated by a rush of new investors, the rise of remote work, cost savings from the cloud, and the desire for more resilient infrastructure. While the promise of the cloud is enticing, the cloud's varying network latencies can lead to market unfairness: orders can be processed out of sequence, and market data can be disseminated to market participants at incorrect times due to varying latencies between participants and the exchange. We present CloudEx, a fair-access cloud exchange, which leverages high-precision software clock synchronization to compensate for noisy network conditions in the public cloud. We also discuss refinements to the CloudEx design that were informed by lessons learned from deploying CloudEx in two academic courses and conclude by outlining future research directions. CCS CONCEPTS• Networks → Cloud computing; • Computer systems organization → Real-time systems; • Applied computing → Online auctions.