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Ethernet is increasingly used in areas where time-critical and safety-relevant data are transported over the network along with best-effort flows, for example in intra vehicle networks or industrial networks. The resulting complex network architectures, time-sensitive networking configurations and system interactions are hard to foresee during the design phase. Therefore, it is hard to rule out any violations of flow specifications or timing and reliability requirements, especially in the presence of unpredictable failures. In this work, the design of a flow-oriented network monitoring system for time-sensitive applications is presented. It continuously supervises relevant performance metrics with high precision and short detection delay. Moreover, it allows to check compliance with flow specifications in real-time. Initial evaluations using intra vehicle network traffic yield a high measurement precision.

In scientific research, the independent reproduction of experimental results is the source of trust. The release of experimental artifacts enables the reproduction of results; however, additional efforts of researchers are required to prepare and document their experiments accordingly. To honor this increased effort, multiple initiatives were implemented to incentivize the creation and release of experimental artifacts, e.g., awards for papers that provide experimental artifacts. In this work, we want to propose a novel approach toward a reproducible research---a structured experimental workflow that allows the creation of reproducible experiments without requiring additional efforts of the researcher. Moreover, we present our own testbed and toolchain, namely, plain orchestrating service (pos), which enables the creation of such experimental workflows. The experiment is documented by our proposed, fully scripted experiment structure. Further, we consider the entire experimental workflow from experiment orchestration, to data measurement, to result evaluation. In addition, pos provides scripts that enable the automation of the bundling and release of all the created experimental artifacts. In this case study, we release one of our own experiments together with the necessary tools so that others can reproduce our experiment. Additionally, we provide an interactive environment where pos experiments can be executed and reproduced, which is available at https://gallenmu.github.io/pos-artifacts.

The SYN flood attack is a common attack strategy as part of Distributed Denial-of-Service, which steadily becomes more frequent and of higher volume. To defend against SYN floods, preventing valuable service downtime, malicious traffic has to be separated from legitimate TCP requests. For this challenge, sophisticated filtering mechanisms operating at high bandwidths are needed.Modern programmable data plane devices can handle traffic in the 10 Gbit/s range without overloading. We discuss how we can harness their performance to defend entire networks against SYN flood attacks. Therefore, we analyze different defense strategies, SYN authentication and SYN cookie, and discuss implementation difficulties when ported to different target data planes: software, network processors, and FPGAs. We provide prototype implementations and performance figures for all three platforms.

We currently see a shift from fixed-function network devices with limited configurability towards network devices with a fully programmable processing pipeline. A prominent example of this development is P4 that provides a language and reference architecture model to design and program network devices. The core element of this reference model is the programmable match-action table that defines the processing steps for the network packets. In this paper, we demonstrate that these tables, which we use to create our own modeling framework, are the key driver of device performance.P4-programmable devices come in a wide variety regarding their underlying hardware architecture, such as CPU-based systems or ASICs, as representatives of both ends of the spectrum. CPU-based P4 target platforms offer limited performance but are easily extensible. ASIC P4 targets have dedicated P4 processing pipelines with limited programmability but offer highly optimized performance. To reflect these fundamental differences, our modeling framework incorporates different approaches to accurately model and predict the performance of P4-enabled devices.

P4 introduces a standardized, universal way for data plane programming. Secure and resilient communication typically involves the processing of payload data and specialized cryptographic hash functions. We observe that current P4 targets lack the support for both. Therefore, applications and protocols, which require message authentication codes or hashing structures that are resilient against attacks such as denial-of-service, cannot be implemented. To enable authentication and resilience, we make the case for extending P4 targets with cryptographic hash functions. We propose an extension of the P4 Portable Switch Architecture for cryptographic hashes and discuss our prototype implementations for three different P4 target platforms: CPU, NPU, and FPGA. To assess the practical applicability, we conduct a performance evaluation and analyze the resource consumption. Our prototype implementations show that cryptographic hashing can be integrated efficiently. We cannot identify a single hash function delivering satisfying performance on all investigated platforms. Therefore, we recommend a set of hash functions to optimize target-specific performance.

Objective Intrathecal (IT) opioid pumps are one therapeutic cornerstone of refractory nonmalignant pain syndromes. The aim of this study was to evaluate the efficacy of and surgical and pharmacological complications of IT pumps beyond a time span of 10 years. Methods In this retrospective single-center cohort study, 27 patients (14 female, 13 male, age 64.0 ± 8.9 [median, 1 SD] years) were identified. Pain intensity using the numeric rating scale (NRS), pain and IT pump characteristics, and complications were analyzed. The German Pain Questionnaire was used to investigate the physical and mental health status. Results Overall time of IT therapy from first implantation to last follow-up was 20.4 ± 6.0 years. Time to implantation of the second pump (n = 18) was 10.0 ± 5.3 years, and between the second and third pump (n = 6) 6.5 ± 2.7 years; 2 patients received their fourth pump 6 years later. The NRS score was 9.0 ± 0.9 before implantation, 7.0 ± 1.8 1 year after implantation, and 4.0 ± 2.3 at the last follow-up. IT drug dose remained stable after 3 years. Opioid intoxications occurred in 3 patients (10%). One patient (3%) underwent revision surgery due to a catheter infection. Drug side effects occurred in 4 patients (14%). Our patient group had pain-related restrictions in physical activities with menial impact regarding mental and emotional stress. Conclusion Even after a time span of over 15 years and several exchanges of pump systems, pain intensity was still reduced. After 3 years, IT drug dose remained unchanged with low side-effect and complication rates.

Das Schadel-Hirn-Trauma bedingt eine erhebliche Morbiditat und stellt die fuhrende Todesursache in der jungeren Bevolkerung dar. Die mit dem Unfallereignis assoziierten Verletzungen reichen von grosen Gewebedefekten uber Blutungen bis hin zu mikroskopischen Schaden am Nervengewebe. Trotz teils schwerster Traumafolgen erreichen heute immer mehr Patienten das Krankenhaus lebend. In der anschliesenden Hospitalphase liegt der therapeutische Focus auf der Minimierung von sekundaren Hirnschaden, die durch erhohten Hirndruck, Ischamie oder Infektionen und Entzundungen entstehen konnen. Kausale Therapieansatze sind rar, so dass die Behandlung symptomatisch orientiert ist.

The impact of invasive hemodynamic monitoring on patient safety and outcome in perioperative medicine remains inadequately tested and unproven. The indications for the use of these tools should, therefore, be evaluated according to an individual risk-benefit analysis. The measurement of central venous oxygen saturation (ScvO2) is of little invasiveness as most high-risk patients are instrumented with central venous catheters, and ScvO2 has been shown to improve outcome in patients with septic shock. Transpulmonary thermodilution (e.g. PiCCO-system) delivers information not only on global cardiac function and intravascular volume status but also helps to define the pulmonary consequences of cardiovascular therapy. Transesophageal echocardiography (TEE) is a valuable tool in patients undergoing cardiac surgery and represents the beside-method of choice for rapid assessment of acute life-threatening cardiovascular instability. Apart from special indications, these tools tend to replace the pulmonary artery catheter (PAC) which has been shown to be of little value in various patient populations.