<p>Med en växande produktionsindustri i Asien så blir det allt svårare för företag i Europa och Sverige att konkurrera med den effektiva och framförallt billiga arbetskraft som erbjuds i öst. För att kunna konkurrera på ett effektivt sätt så har industrirobotindustrin växt kraftigt under de senaste åren. Detta är en rapport på hur ett koncept har påbörjats för att implementera ett Ethernet baserat kommunikationssystem kallat EtherCAT i ett robotsystem från Motoman. En testutrustning har byggts och simulerat en kommunikation med en PLC. Ett första HMI gränssnitt har skrivits som översätter informationen från PLCn för att göra informationen lättförståelig för människor. Det har förberetts ett robotprogram till en robot från Motoman. Rapporten innehåller också en faktadel för hur EtherCAT fungerar och en jämförelse med andra systembussar.</p> / <p>With a fast growing production industry in Asia it’s getting harder and harder for Swedish companies to compete with the low production cost that the east offers. To be more competitive robot solutions are used more and more. This is a report of a first concept to implement a new Ethernet based communication called EtherCAT, in one of Motoman robot controllers. Test equipment has been constructed and simulated a communication with the PLC. A first HMI interface has been written to show the information from the PLC in a way that is understandable for humans. For one of Motoman’s robots a program has been prepared.</p>

In this diploma thesis, the implementation of a networking protocol, which is adopted from a previous work, is refined to a state where it is ready for production use. The protocol is tailored for the specific needs in a cluster environment which uses standard ethernet as the interconnection hardware. Thereby focuses is on developing and implementing a flow control which is very lightweigt in terms of processing overhead and copes the challenges of such a tightly coupled network gracefully. Second, the Log(G)P models for parallel computation are examined and it is shown that they do not give a usable definition of the overhead or latency parameters for protocols whose overhead is O(message size)–instead, the P-LogP model is used to characterize the protocol and for comparisons to the TCP/IP protocol suite. Last, it is demonstrated that the protocol gives usable results with real-world scientific applications.

Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Xin Yuan, Florida State University, College of Arts and Sciences, Dept. of Computer Science. Title and description from dissertation home page (viewed Oct. 3, 2003). Includes bibliographical references.

Analog-to-Digital (ADC) converters have been an essential building block of electronic design for years. As ADC components get faster, new data interfaces are required in order to keep up with the faster data rates while providing very high data integrity. The objective of this project was to design an inter-IC ADC interface for converters with data bandwidths as high as 56 Gigabytes per second. The main goal for this project was to create a mechanism for interfacing a general-purpose high-speed ADC integrated circuit with an FPGA. This will enable applications that can benefit from the reprogrammability offered by FPGAs as well as those that could not justify a monolithic integrated solution for cost reasons. The interface presented is based on the physical layer of the IEEE 10GBASE-KR specification for 10 Gigabit Ethernet (10GE). Leveraging this specification provides significant benefits as it defines most of the services required by the interface, such as effcient encoding and forward error correction. Furthermore, using an interface as widely used as 10GBASE-KR leverages significant validation work as well as widespread support in mainstream FPGAs and by IP providers. The report will provide an analysis of the requirements of the ADC interface and a description of the architecture proposed. One key aspect of the design of the system was the analysis of the e ects of random bit errors in the channel and how to deal with them while making a robust interface. The causes of error are described and the critical sections of the system were simulated to validate the choice of Forward Error Correction solution. Finally, the report describes the working prototype system built in an FPGA board and provides a description of the performance achieved. / text

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Network switches are a critical component in any networked FTI data acquisition system in order to allow the forwarding of data from the DAU to the target destination devices such as the network recorder, PCM gateways, or ground station. Larger configurations require one or more switch boxes to handle aggregation, routing, filtering and synchronization via the IEEE 1588 Precision Time Protocol. However, for smaller configurations where space and weight restrictions are more stringent, a separate switch box may not be practical This paper discusses how all the essential features of an FTI network, such as flexible forwarding and filtering and IEEE 1588 synchronization, can be maintained without the need for the separate switch box thus making significant savings on weight and size and reducing cost.

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / During a recent U.S. Army Yuma Proving Ground (YPG) ground test, an unexpected change in test location resulted in the implementation of an innovative ad hoc network solution to complete the planned test matrix. The original plan was to use an aircraft ground test facility; however, safety requirements resulted in the aircraft being placed 50 meters away from the facility. This distance was too great to use the existing connections; consequently, data collection and analysis were adversely affected until this time expedient solution was implemented.

Η δομή της εργασίας χωρίζεται σε πέντε μέρη. Στο πρώτο κεφάλαιο γίνεται μια παρουσίαση των δικτύων υπολογιστών και του μοντέλου αναφοράς OSI που χρησιμοποιείται για την περιγραφή τους. Στο δεύτερο κεφάλαιο παρουσιάζεται το πρωτόκολλο επικοινωνίας TCP και αναλύονται οι μηχανισμοί και οι υπηρεσίες που παρέχει. Στο τρίτο κεφάλαιο μελετάται η υλοποίηση του πρωτοκόλλου TCP στον πυρήνα του λειτουργικού συστήματος Linux και προτείνονται μέθοδοι εκτενούς παρακολούθησης της λειτουργίας του σε πραγματικό χρόνο χρησιμοποιώντας τις δυνατότητες που παρέχει ο πυρήνας του λειτουργικού συστήματος. Το τέταρτο κεφάλαιο περιλαμβάνει την πειραματική διαδικασία. Μέσα από συγκεκριμένα σενάρια που υλοποιούνται σε ένα οικιακό τοπικό δίκτυο, εξετάζεται και αξιολογείται η λειτουργία πέντε διαφορετικών αλγορίθμων συμφόρησης του πρωτοκόλλου TCP, οι οποίοι αποτελούν κομμάτι του πυρήνα του λειτουργικού συστήματος. Τέλος στο πέμπτο κεφάλαιο παίρνοντας σαν αφορμή τα αποτελέσματα της συγκριτικής αξιολόγησης των πέντε αλγορίθμων προτείνονται μικρές τροποποιήσεις στον κώδικα του ενός από αυτούς με στόχο την βελτίωση της λειτουργίας του στο συγκεκριμένο τοπικό δίκτυο. / Η δομή της εργασίας χωρίζεται σε πέντε μέρη. Στο πρώτο κεφάλαιο γίνεται μια παρουσίαση των δικτύων υπολογιστών και του μοντέλου αναφοράς OSI που χρησιμοποιείται για την περιγραφή τους. Στο δεύτερο κεφάλαιο παρουσιάζεται το πρωτόκολλο επικοινωνίας TCP και αναλύονται οι μηχανισμοί και οι υπηρεσίες που παρέχει. Στο τρίτο κεφάλαιο μελετάται η υλοποίηση του πρωτοκόλλου TCP στον πυρήνα του λειτουργικού συστήματος Linux και προτείνονται μέθοδοι εκτενούς παρακολούθησης της λειτουργίας του σε πραγματικό χρόνο χρησιμοποιώντας τις δυνατότητες που παρέχει ο πυρήνας του λειτουργικού συστήματος. Το τέταρτο κεφάλαιο περιλαμβάνει την πειραματική διαδικασία. Μέσα από συγκεκριμένα σενάρια που υλοποιούνται σε ένα οικιακό τοπικό δίκτυο, εξετάζεται και αξιολογείται η λειτουργία πέντε διαφορετικών αλγορίθμων συμφόρησης του πρωτοκόλλου TCP, οι οποίοι αποτελούν κομμάτι του πυρήνα του λειτουργικού συστήματος. Τέλος στο πέμπτο κεφάλαιο παίρνοντας σαν αφορμή τα αποτελέσματα της συγκριτικής αξιολόγησης των πέντε αλγορίθμων προτείνονται μικρές τροποποιήσεις στον κώδικα του ενός από αυτούς με στόχο την βελτίωση της λειτουργίας του στο συγκεκριμένο τοπικό δίκτυο.

10 Gigabit Ethernet (GbE) demands faster optical sources to support high modulation rates. At the same time, the allowable margin in the 10 GbE link power budget is decreasing. This means that a 10 GbE system is unable to support as many tight bends, and it is more difficult to avoid the costly downtime that results when the allowable margin is exceeded. The recent introduction of bend-optimized (BO) multimode fiber (MMF) provides a clear solution. 850 nm vertical cavity surface emitting lasers (VCSELs) and MMFs have long been the most cost effective choice for short reach premise applications. As will be shown, the combination of BO-MMF with VCSELs is even more attractive.Historically, MMF systems operating at low bit rates of 10-100 Mbps used light-emitting diodes (LED) sources, which launch nearly equal power into every fibermode. This launch is approximated by the overfilled launch (OFL), which is still used to characterize the core diameter and numerical aperture of MMF. Unlike LEDs, VCSELs typically underfill the fiber core and are better represented by an encircled flux launch (EFL). Using OFL to evaluate a VCSEL-based MMF system could therefore produce inaccurate and misleading results. A recent study [1] characterized the macrobend loss of MMF with overfilled and restricted mode offset launch conditions. In this study, the MMFs performance with an EFL is evaluated, which is a more relevant launch condition for laser transmission. The impact of both launch conditions, OFL and EFL, on MMF performance is studied and compared.We characterize macrobend losses at small bend radii and their impact on thebandwidth for both standard 50/125 um MMF and a newly introduced BO-MMF.In addition, the 10 GbE link performance is also evaluated using the IEEE link model P802.3ae3.The simulation results illustrate that both macrobend loss and bandwidth are vital to the overall optical link performance. The 10 GbE link performance of the standard fiber deteriorates with macrobends, while the bend-optimized fiber is insensitive to the deployment conditions.

Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations. Continuity and supplier independence are a cause of concern with current proprietary real-time networks. This project evaluates the capability of providing real-time traffic over switched Ethernet with EDF scheduling algorithm implemented at both the switch and the node. By using OMNET simulation tool at packet level, it is shown that the EDF implementation in switched Ethernet can guarantee real-time traffic over the network and at the same time supporting non real-time traffic.

Recently, simulation has became the most effective way for analyzing and perfecting the performance of telecommunication networks. It has proven itself as the best method in the realm of education, where the hardware capabilities for practical training are often limited. A simulated network enables students to practice hands-on network programming and to understand, in a practical way, how a data communication network operates and how protocols work.Metanet is an environment that enables the programmer to write networking applications and to test them as if using an IP network with the hosts connected through Ethernet. The whole software is a multi-process application that makes use of just the resources offered by a single machine. It runs on a UNIX system and emulates hosts that also communicate through an emulated network using TCP/IP. Each layer of the hosts' operating system is designed as a separate process that will communicate with the adjacent layers using socket pairs or UDP connections. The application layer has multi-processing capability. / Department of Computer Science