Asynchronous Time-Sensitive Networking for Industrial Networks

Time-Sensitive Networking (TSN) is expected to be a cornerstone in tomorrow’s industrial networks. That is because of its ability to provide deterministic quality-of-service in terms of delay, jitter, and scalability. Moreover, it enables more scalable, more affordable, and easier to manage and operate networks compared to current industrial networks, which are based on Industrial Ethernet. In this article, we evaluate the maximum capacity of the asynchronous TSN networks to accommodate industrial traffic flows. To that end, we formally formulate the flow allocation problem in the mentioned networks as a convex mixed-integer non-linear program. To the best of the authors’ knowledge, neither the maximum utilization of the asynchronous TSN networks nor the formulation of the flow allocation problem in those networks have been previously addressed in the literature. The results show that the network topology and the traffic matrix highly impact on the link utilization.This work has been partially funded by the H2020 research and innovation project 5G-CLARITY (Grant No. 871428), national research project TRUE5G: PID2019-108713RB-C5

Backscatter from the Data Plane --- Threats to Stability and Security in Information-Centric Networking

Information-centric networking proposals attract much attention in the ongoing search for a future communication paradigm of the Internet. Replacing the host-to-host connectivity by a data-oriented publish/subscribe service eases content distribution and authentication by concept, while eliminating threats from unwanted traffic at an end host as are common in today's Internet. However, current approaches to content routing heavily rely on data-driven protocol events and thereby introduce a strong coupling of the control to the data plane in the underlying routing infrastructure. In this paper, threats to the stability and security of the content distribution system are analyzed in theory and practical experiments. We derive relations between state resources and the performance of routers and demonstrate how this coupling can be misused in practice. We discuss new attack vectors present in its current state of development, as well as possibilities and limitations to mitigate them.Comment: 15 page

Development of prototype components for the Silicon Tracking System of the CBM experiment at FAIR

Das CBM-Experiment an der zukuenftigen Beschleunigeranlage FAIR wird die Eigenschaften von Kernmaterie unter extremen Bedingungen untersuchen. Das experimentelle Programm unterscheidet sich von den Schwerionen-Experimenten an RHIC (BNL) und LHC (CERN), die Kernmaterie bei hohen Temperaturen erzeugen. Im Gegensatz dazu kann die Untersuchung des QCD-Phasendiagramms, im Bereich der hoechsten Nettobaryonendichten und moderaten Temperaturen, die nur schwach untersucht wurden, mit hoher Praezision durchgefuehrt werden. Hierzu werden Kollisionen der verschiedenen Schwerionenstrahlen, bei Energien von 10-45GeV/Nukleon, mit nuklearem Target gemessen. Das physikalische Programm des CBM Experimentes umfasst die Messung sowohl der seltenen Sonden als auch der Mengenobservablen, die aus verschiedenen Zeitphasen des Zusammenstosses der Kerne stammen. Insbesondere kann der Zerfall von Teilchen mit Charm-Quarks durch Rekonstruktion des Zerfallsvertex, versetzt von dem primaeren Wechselwirkungspunkt um mehrere hundert Mikrometer, registriert werden. Hierzu ist praezises Tracking bei voller Ereignisrekonstruktion, mit bis zu 600 Spuren der geladenen Teilchen pro Ereignis innerhalb der Akzeptanz, noetig. Andere seltene Sonden erfordern den Betrieb bei einer Wechselwirkung von bis zu 10 MHz. Das Detektor-System, dass Tracking durchfuehrt, muss eine hohe Ortsaufloesung, auf der Ebene von 10 um leisten, mit hohen Arbeitsgeschwindigkeiten zu betreiben sein und ebenso ein strahlungstolerantes Design mit geringem Materialbudget besitzen. Das Silicon Tracking System (STS) wurde entwickelt um die Spuren geladener Teilchen in einem Magnetfeld zu rekonstruieren. Das System besteht aus acht Tracking Stationen, die sich in der Oeffnung eines Dipolmagneten mit 1T Feld befinden. Bei Spuren mit Impulsen ueber 1 GeV, betraegt die Impulsaufloesung bei einem solchen System etwa 1%. Um diese Aufgabe erfuellen zu koennen, ist eine sorgfaeltige Optimierung des Detektordesigns erforderlich. Insbesondere muss ein minimales Materialbudget erreicht werden. Die Herstellung eines Detektor-Moduls erfordert Aktivitaeten mit Bezug auf die Modul-Komponenten und deren Integration. Ein Detektor-Modul ist eine grundlegende funktionelle Einheit, die einen Sensor, ein Analogmikrokabel und Front-End-Elektronik umfasst, montiert auf einer Traegerstruktur. Das Ziel der Arbeit ist es, die Qualitaetssicherungstests der Prototyp-Modulkomponenten, zur Bestaetigung des Detektor-Modul-Konzeptes durchzufuehren, und um seinen Betrieb mit radioaktiven Quellen und Teilchenstrahlen zu demonstrieren. Die doppelseitigen Silizium-Mikrostreifendetektoren wurden als Sensortechnik fuer den STS, aufgrund der Kombination einer guten Ortsaufloesung, einer zweidimensionalen Koordinatenmessung mit geringem Materialbudget (0.3%X0), der hohen Auslesegeschwindigkeit und ausreichender Strahlungstoleranz gewaehlt. Mehrere Generationen von doppelseitigen Silizium-Mikrostreifendetektoren wurden zur Erkundung strahlenharter Konstruktionsmerkmale und des Konzepts, eines grossflaechigen Sensors und dessen Kompatibilitaet mit der Leiter-Struktur des Detektor-Moduls, hergestellt. Insbesondere wurden Sensoren mit doppelter Metallschicht auf beiden Seiten und aktivem Bereich von 62x62 mm2 produziert. Die elektrische Charakterisierung der Sensoren wurde durchgefuehrt, um die gesamte Bedienbarkeit sowie die Extrahierung der Geraeteparameter feststellen zu koennen. Strom und Kapazitaets-Spannungs-Charakteristiken sowie Interstreifenparameter wurden gemessen. Das Auslesen der Sensoren wurde mithilfe einer selbstgetriggerten Front-End-Elektronik getaetigt. Ein Front-End-Board wurde auf der Grundlage eines n-XYTER-Auslesechips mit datengesteuerter Architektur entwickelt, der geeignet ist bei Auslesegeschwindigkeit von 32MHz betrieben zu werden. Die Front-End-Platine enthaelt einen externen Analog-zu-Digital-Wandler (ADC). Die Kalibrierung des ADC wurde unter Verwendung von sowohl Roentgenquelle als auch eines Impulsgenerators vorgenommen. Die Schwellenkalibrierung und Untersuchung der Temperaturabhaengigkeit der Chip-Parameter wurden durchgefuehrt. Die ultraleichten Halterungsstrukturen wurden aus Kohlefaser entwickelt, diese haben die Steifigkeit, die Detektor-Module halten, und die minimale Coulomb-Streuung der Teilchenspuren einbeziehen zu koennen. Es wurden Analogmikrokabel mit Aluminiumleiterbahnen auf einem Polyimidsubstrat produziert - eine Kombination von guter elektrischer Verbindung und geringem Materialbudget. Die Mikrokabelstruktur umfasst mehrere Lagen optimiert fuer die niedrige Kapazitaet der Leiterbahnen und den damit verbundenen geraeuscharmen Betrieb. Es wurden Analog-Mikrokabel mit Aluminiumleiterbahnen auf einem Polyimidsubstrat produziert, also eine Kombination von guter elektrischer Verbindung und geringem Materialbudget. Die Mikrokabelstruktur umfasst mehrere Lagen optimiert fuer die niedrige Kapazitaet und den damit verbundenen geraeuscharmen Betrieb. Es wurde ein Demonstrator-Tracking-Teleskop gebaut und in mehreren Strahltests, einschliesslich 2.5 GeV Protonenstrahl an COSY (Juelich), betrieben. Drei Tracking-Stationen wurden mit Hodoskopen ergaenzt. Die Datenanalyse ergab Informationen ueber Analog- und Zeitverhalten sowie Strahlenprofil. So wurden Tracking- und Alignmentinformationen erhalten. Mit speziell entwickelten Monitoring-Tools wurde die Strahlstabilitaet bewertet. Als Ergebnis der Studien, wurde die Leistung der Modulkomponenten bewertet und die Anforderungen zum Detektormodul formuliert. Die genaue Definition des endgueltigen Detektormoduldesigns jedoch, war ausserhalb des Geltungsbereichs dieser Arbeit.The CBM experiment at future accelerator facility FAIR will investigate the properties of nuclear matter under extreme conditions. The experimental programm is different from the heavy-ion experiments at RHIC (BNL) and LHC (CERN) that create nuclear matter at high temperatures. In contrast, the study of the QCD phase diagram in the region of the highest net baryon densities and moderate temperatures that is weakly explored will be performed with high precision. For this, collisions of different heavy-ion beams at the energies of 10–45GeV/nucleon with nuclear target will be measured. The physics programme of the CBM experiment includes measurement of both rare probes and bulk observables that originate from various phases of a nucleus-nucleus collision. In particular, decay of particles with charm quarks can be registered by reconstructing the decay vertex detached from the primary interaction point by several hundreds of micrometers (e.g., decay length c Tau = 123 µm for D0 meson). For this, precise tracking and full event reconstruction with up to 600 charged particle tracks per event within acceptance are required. Other rare probes require operation at interaction rate of up to 10MHz. The detector system that performs tracking has to provide high position resolution on the order of 10 µm, operate at high rates and have radiation tolerant design with low material budget. The Silicon Tracking System (STS) is being designed for charged-particle tracking in a magnetic field. The system consists of eight tracking station located in the aperture of a dipole magnet with 1T field. For tracks with momentum above 1GeV, momentum resolution of such a system is expected to be about 1%. In order to fulfill this task, thorough optimization of the detector design is required. In particular, minimal material budget has to be achieved. Production of a detector module requires research and development activities with respect to the module components and their integration. A detector module is a basic functional unit that includes a sensor, an analogue microcable and frontend electronics mounted on a support structure. The objective of the thesis is to perform quality assurance tests of the prototype module components in order to validate the concept of the detector module and to demonstrate its operation using radioactive sources and particle beams. Double-sided silicon microstrip detectors have been chosen as sensor technology for the STS because of the combination of a good spatial resolution, two-dimensional coordinate measurement achieved within low material budget (0.3%X0), high readout speed and sufficient radiation tolerance. Several generations of double-sided silicon microstrip sensors have been manufactured in order to explore the radiation hard design features and the concept of a large-area sensor compatible with ladder-type structure of the detector module. In particular, sensors with double metal layer on both sides and active area of 62×62mm2 have been produced. Electrical characterization of the sensors has been performed in order to establish the overall operability as well as to extract the device parameters. Current-voltage, capacitance-voltage characteristics and interstrip parameters have been measured. Readout of the sensors has been done using self-triggering front-end electronics. A front-end board has been developed based on the n-XYTER readout chip with data driven architecture and capable of operating at 32MHz readout rate. The front-end board included an external analog-to-digital converter (ADC). Calibration of the ADC has been performed using both 241Am X-ray source and external pulse generator. Threshold calibration and investigation of temperature dependence of chip parameters has been carried out. Low-mass support structures have been developed using carbon fibre that has the rigidity to hold the detector modules and introduce minimal Coulomb scattering of the particle tracks. Analogue microcables have been produced with aluminium traces on a polyimide substrate, thus combining good electrical connection with low material budget. Microcable structure includes several layers optimized for low trace capacitance and thus low-noise performance. A demonstrator tracking telescope has been constructed and operated in several beam tests including 2.5GeV proton beam at COSY synchrotron (Jülich). Three tracking stations have been complemented with several beam hodoscopes. Analysis of the beam data has yielded information on analogue and timing response, beam profile. Tracking and alignment information has been obtained. Beam stability has been evaluated using specially developed monitoring tools. As a result of conducted studies, performance of the module components have been evaluated and requirements to the detector module have been formulated. Practical suggestions have been made with respect to the structure of the detector module, whereas precise definition of the final detector module design was outside of the scope of this thesis

A circuit based Evolvable Hardware Architecture

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 69-72).This thesis presents an Evolvable Hardware Architecture that was developed in the Quantum Nanostructures and Nanofabrication Laboratory. We believe intrinsic evolution is a promising tool that can be used to exploit the physics of complex systems. I present a reconfigurable analog circuit platform that is coupled with a genetic algorithm to evolve circuit functions. The design process is detailed along with the results of three evolved circuits. Our coarse grained analog system parallels other evolvable hardware platforms that have been developed using the same architecture. I place our platform in the context of other efforts in the field and our intentions for future work. The speed and complexity of our board is discussed with areas for future development outlined.by Delano Christopher Sanchez.S.M

HARMONIC AND RANDOM VIBRATION DURABILITY INVESTIGATION FOR SAC305 (Sn3.0Ag0.5Cu) SOLDER JOINT

ABSTRACT Title of Dissertation: HARMONIC AND RANDOM VIBRATION DURABILITY INVESTIGATION FOR SAC305 (Sn3.0Ag0.5Cu) SOLDER INTERCONNECTS Yuxun Zhou, Doctor of Philosophy, 2008 Dissertation directed by: Professor Abhijit Dasgupta Department of Mechanical Engineering Vibration loading is commonly encountered during the service life of electronic products. However, compared to thermal cycling durability, vibration durability is more complex and has been less investigated. In surface mount technology, solder joints are the primary mechanical, thermal and electrical interconnects between the component and the PWB. So the reliability of solder joints is very crucial for most electronic assemblies. The vibration durability of Pb-free solder joints is the focus of this dissertation. The characteristics of the stress from vibration loading are low amplitude and high frequency, while those from cyclic thermal loading are high amplitude and low frequency. In this study, several exploratory vibration tests were conducted, using both narrow band and broad-band, step-stress excitation at several different isothermal and thermal cycling conditions. The effect of thermal pre-aging on solder joint vibration failures was also investigated. Some of the vibration durability results were analyzed in detail, to obtain quantitative insights into the vibration fatigue behavior of the SAC305 solder material. A time-domain approach was adopted to investigate the durability of solder interconnects under different kinds of vibration and quasi-static mechanical loading. First, the solder interconnects were subjected to narrow-band (harmonic) vibration loading. The test were conducted at the first natural frequency of the test board using constant-amplitude excitation and solder fatigue properties were extracted with the help of a time-domain analysis that is based on quasi-static finite element simulation. Compared to broad-band step-stress vibration durability tests, the advantage of the harmonic constant-amplitude test is less complexity in the model extraction process, hence, less uncertainty in the desired fatigue constants. Generalized strain-based S-N curves have been obtained for both SAC305 and Sn37Pb solder materials. The strain-life model constants show that SAC305 solder material has superior fatigue properties compared to Sn37Pb solder material under low-cycle fatigue loading, while the reverse is true for high-cycle fatigue loading. These results are consistent with test results from other researchers. In actual application, SAC305 assemblies almost always fail before Sn37Pb assemblies under comparable vibration excitation because of (i) higher solder strain at a given excitation level; and (ii) multiple failure modes such as copper trace cracking. Next, durability was investigated under step-stress, broad-band (random) excitation. These test results show that SAC305 interconnects are less durable than Sn37Pb interconnects under the random excitation used in this study, which agrees with the harmonic durability results. The random and harmonic durability results were quantitatively compared with each other in this study. Finite element simulation was used to investigate the stress-strain response in the interconnects. The output of this simulation is the strain transfer function due to the first flexural mode of the PWB. This transfer function is used to obtain the solder strain from the measured board strain. This fatigue assessment method demonstrated that the model constants obtained from the harmonic test overestimate the fatigue life under random excitation by an order of magnitude. The causes for this discrepancy were systematically explored in this study. The effects of cyclic loading and mean stress on the vibration durability were addressed and found to be minimal in this study. The stress-strain curves assumed for the solder material were found to have a very large effect on the durability constants, thus affecting the agreement between harmonic and random durability results. The transient response of the components on the test board under both harmonic and random excitation was also included in the strain transfer function with the help of dynamic implicit simulation, and found to have a much stronger effect on the vibration durability at the high frequencies used in broad-band excitation compared to the low frequency used in narrow-band test. Furthermore, the higher PWB vibration modes may play a strong role and may need to be included in the strain transfer-function. This study clearly reveals that the solder strain analysis for broad-band random excitation cannot be limited to the quasi-static strain transfer-function based on the first PWB flexural mode, that has been used in some earlier studies in the literature. The time-domain approach used in this study provided fundamental and comprehensive insights into the key factors that affect vibration durability under different types of excitation, thus leading to a generalized S-N modeling approach that works for both harmonic and random vibration loading

DESIGN, CONFIGURATION AND IMPLEMENTATION OF FIELDBUS SYSTEM FOR CONTROLLING OF A PROCESS PLANT

The first process control systems used mechanical and pneumatic controllers, and were run conservatively for stability rather than economic performance. In the 1950s, the first electronic controllers were introduces that used analog signals with simple devices, and later in the 1970s distributed control system (DCS) emerged, which is the current standard for large control system. In DCS however, a central processor controls all parameters and has limitation in terms of reliability and cost. This lead to the introduction of fieldbus system: the digital communication and fieldbus system replaces the DCS architecture by enabling distribution of control function to equipment in the field such as sensors, controllers and actuators. This report discusses the findings on the literature review of fieldbus system and the fundamental issues in the development and implementation of a fieldbus system for controlling a simple process loop using a fieldbus test rig. A configuration and implementation procedure for the development of a fieldbus test rig is presented involving process variables that are pressure, temperature and flow. A complete control system functions implemented are the monitoring, measurement and control. The methodology towards accomplishing the project includes the theoretical and technical research, the installation and commissioning, the configuration of network, device and control strategy, the troubleshooting, operation and maintenance, and the analysis on the fieldbus savings and its benefits. Detailed design, configuration and implementation for a temperature control are presented. The findings demonstrate the benefits of the fieldbus system over the DCS in terms of signal conditioning, loop interconnection and configurations and verify the qualitative characteristics of the fieldbus system in terms of simpler and better controllability

Performance Comparison of 112 Gb/s DMT, Nyquist PAM4 and Partial-Response PAM4 for Future 5G Ethernet-based Fronthaul Architecture

For a future 5G Ethernet-based fronthaul architecture, 100G trunk lines of a transmission distance up to 10 km over a standard single-mode fiber (SSMF) in combination with cheap gray optics to daisy chain cell site network interfaces are a promising cost- and power-efficient solution. For such a scenario, different intensity modulation and direct detect formats at a data rate of 112 Gb/s, namely Nyquist four-level pulse amplitude modulation (PAM4), discrete multitone transmission (DMT), and partial-response (PR) PAM4, are experimentally investigated, using a low-cost electroabsorption modulated laser, a 25G driver, and current state-of-the-art high-speed 84-GS/s CMOS digital-to-analog converter and analog-to-digital converter test chips. Each modulation format is optimized independently for the desired scenario, and their digital signal processing requirements are investigated. The performance of Nyquist PAM4 and PR PAM4 depends very much on the efficiency of pre- and postequalization. We show the necessity for at least 11 feedforward equalizer (FFE) taps for pre-emphasis and up to 41 FFE coefficients at the receiver side. In addition, PR PAM4 requires a maximum likelihood sequence estimation with four states to decode the signal back to a PAM4 signal. On the contrary, bit loading and power loading are crucial for DMT, and an FFT length of at least 512 is necessary. With optimized parameters, all modulation formats result in a very similar performances, demonstrating a transmission distance of up to 10 km over an SSMF with bit error rates below an FEC threshold of 4.4E-3, allowing error-free transmission

Optically-Connected Memory: Architectures and Experimental Characterizations

Growing demands on future data centers and high-performance computing systems are driving the development of processor-memory interconnects with greater performance and flexibility than can be provided by existing electronic interconnects. A redesign of the systems' memory devices and architectures will be essential to enabling high-bandwidth, low-latency, resilient, energy-efficient memory systems that can meet the challenges of exascale systems and beyond. By leveraging an optics-based approach, this thesis presents the design and implementation of an optically-connected memory system that exploits both the bandwidth density and distance-independent energy dissipation of photonic transceivers, in combination with the flexibility and scalability offered by optical networks. By replacing the electronic memory bus with an optical interconnection network, novel memory architectures can be created that are otherwise infeasible. With remote optically-connected memory nodes accessible to processors as if they are local, programming models can be designed to utilize and efficiently share greater amounts of data. Processors that would otherwise be idle, being starved for data while waiting for scarce memory resources, can instead operate at high utilizations, leading to drastic improvements in the overall system performance. This work presents a prototype optically-connected memory module and a custom processor-based optical-network-aware memory controller that communicate transparently and all-optically across an optical interconnection network. The memory modules and controller are optimized to facilitate memory accesses across the optical network using a packet-switched, circuit-switched, or hybrid packet-and-circuit-switched approach. The novel memory controller is experimentally demonstrated to be compatible with existing processor-memory access protocols, with the memory controller acting as the optics-computing interface to render the optical network transparent. Additionally, the flexibility of the optical network enables additional performance benefits including increased memory bandwidth through optical multicasting. This optically-connected architecture can further enable more resilient memory system realizations by expanding on current error dectection and correction memory protocols. The integration of optics with memory technology constitutes a critical step for both optics and computing. The scalability challenges facing main memory systems today, especially concerning bandwidth and power consumption, complement well with the strengths of optical communications-based systems. Additionally, ongoing efforts focused on developing low-cost optical components and subsystems that are suitable for computing environments may benefit from the high-volume memory market. This work therefore takes the first step in merging the areas of optics and memory, developing the necessary architectures and protocols to interface the two technologies, and demonstrating potential benefits while identifying areas for future work. Future computing systems will undoubtedly benefit from this work through the deployment of high-performance, flexible, energy-efficient optically-connected memory architectures