Search results for "ether"
showing 10 items of 986 documents
Present state of the MAMI control system
1990
Abstract MAMI (Mainz Microtron) is an electron accelerator consisting of a cascade of three race-track microtrons, with an output electron beam of 855 MeV and 100 μA cw [1]. The first two stages (output energy 180 MeV) were operative for nuclear-physics experiments from 1983 to 1987 and have since been transferred to a new building. They will serve as an injector for the third stage, now under construction. The control system for MAMI was based on a versatile process communication software system for a network of processors with multiprocess operating systems. This system has previously proved very successful, so we decided to rely on it as control system for the new, upgraded accelerator, …
SmartARP: merging IP and MAC addressing for low-cost gigabit Ethernet networks
1999
Abstract Address Resolution Protocol (ARP) is one of the key TCP/IP stack protocols, used on LANs to map 32 bit IP addresses into 48 bit hardware addresses. Regular ARP uses MAC layer broadcasts to perform the mapping. In this paper a new server-based ARP extension (smartARP) is proposed, which allows the extension of ARP functionality beyond a single MAC layer broadcast domain. Compared to regular IP router, smartARP together with simple broadcast-filtering switches presents a low-cost alternative for forwarding packets between MAC layer broadcast domains. SmartARP is transparent to existing IP hosts, operates independent of LAN speed, and scales for big networks.
Switched Ethernet Networking over LEO Satellite
2005
Satellite onboard switching capabilities, and their possibility to enable "over-the-air" networks, are a strongly innovative achievement of modern satellite communication. The exploitation of satellite networking is especially relevant in the case of low Earth orbit satellites (LEO), where the reduced latency makes a LEO mesh network highly appealing and competitive with terrestrial solutions also in terms of performance. However, while the idea of a LEO mesh network is well understood, we are far from an ultimate answer on which is the best and more appropriate networking solution for moving LEO satellite network nodes. This paper promotes the adoption of existing layer-2 networking soluti…
Adding Real-Time Networking and QoS Capabilities to RTLinux-GPL
2006
This paper presents an architecture to build distributed embedded real-time systems in the RTLinux-GPL platform. The architecture (built in a layered fashion) has being built around open source projects ranging from Ethernet drivers to a CORBA environment. The paper focuses on those layers that give support for QoS and real-time networking over Ethernet networks. The main ideas are: to accomplish deterministic access times by using a TDMA protocol over Ethernet and to multiplex different types of traffic in that real-time network, providing different service types (QoS) to each type of traffic without jeopardizing the a priori guarantee of the system's real-time properties. Traffic types in…
The UJI industrial robotics telelaboratory: Real-time vision and networking
2008
In this video we present a work in progress in the UJI (i.e. the acronym for University Jaume I) robotics telelaboratory. This telelaboratory uses a remote control system based on networked robots and FPGAs technology. The main devices included in this cell are: a SCARA manipulator (AdeptOne), a robot arm with six degrees of freedom (Motoman), an industrial belt, several sensors and cameras, an FPGA that takes care of the computer vision algorithms (i.e. including grasping determination), and a distributed architecture that allows any user to control remotely via Internet a specific manufacturing task. The different components of this system are connected by a 100BaseT Ethernet network and …
MECDAS/spl minus/a distributed data acquisition system for experiments at MAMI
1994
For coincidence experiments with the three-spectrometer setup at MAMI an experiment control and data acquisition system has been built and was put successfully into final operation in 1992. MECDAS is designed as a distributed system using communication via Ethernet and optical links. At the front end, VMEbus systems are used for real time purposes and direct hardware access via CAMAC, Fastbus or VMEbus. RISC workstations running UNIX are used for monitoring, data archiving and online and offline analysis of the experiment. MECDAS consists of several fixed programs and libraries, but large parts of readout and analysis can be configured by the user. Experiment specific configuration files ar…
LSOM: A Link State protocol Over MAC addresses for metropolitan backbones using Optical Ethernet switches
2003
This paper presents a new protocol named "Link State Over MAC" (LSOM) for Optical Ethernet switches to allow the use of active loop topologies, like meshes, in Metropolitan Area Networks (MAN) or even Wide Area Networks (WAN) backbone. In this respect, LSOM is an alternative to a ring topology as proposed in draft IEEE 802.17 Resilient Packet Ring (RPR) or a tree topology using IEEE802. 1D Rapid Spanning Tree Protocol (RSTP). LSOM provides higher scalability and is able to achieve better bandwidth utilization and lower latency than RSTP and RPR. Simulation results for 4-node and 9-node topologies show that LSOM can improve throughput over RPR by a factor of up to 1.7. Furthermore, full free…
Ethernet FSO Communications Link Performance Study Under a Controlled Fog Environment
2012
In this letter the performance of a free space optical (FSO) communication link in the presence of fog is experimentally investigated in an indoor environment. A dedicated indoor atmospheric chamber, replicating the outdoor environment, is being used to evaluate the FSO link performance under the fog condition. Theoretical analysis supported by the experimental evaluation has been carried out for the intensity modulation/direct detection on-off keying non-return-to-zero (OOK-NRZ), OOK return-to-zero (OOK-RZ) and four pulse position modulation (4-PPM) modulation formats at the Ethernet baseline data-rate. The results shown indicate that the 4-PPM signalling scheme is the most robust to the f…
A CORBA based architecture for distributed embedded systems using the RTLinux-GPL platform
2004
This paper describes an architecture for distributed computing on the RTLinux-GPL(GPL version of RTLinux, hereafter RTLinux) platform. The proposed architecture implements the CORBA (common object request broker architecture) model of computation, more specifically the minimum CORBA specification for embedded systems, and also provide the extensions for real-time computing. Since RTLinux lacks networking capabilities, the architecture implements all the required functionality in a layered fashion: network drivers, TCP/IP stack and an ORB (object request broker). Most of this work consists on a set of partings of some widely known open source Linux projects to RTLinux: Linux Ethernet device …
ZERO: An Efficient Ethernet-Over-IP Tunneling Protocol
2013
An Ethernet over IPv4 tunneling protocol is proposed, which categorizes all Ethernet frames to be tunneled into NICE and UGLY frames. The UGLY frames are tunneled by traditional methods, such as UDP or GRE encapsulation, resulting in substantial overhead due to additional headers and fragmentation usually required to transport long Ethernet frames over IP network typically limited to MTU=1,500 bytes. Meanwhile the NICE Ethernet frames are tunneled without any overhead as plain IPv4 packets due to non-traditional reuse of “fragment offset” or “identification” field in the IP header. It is shown that for typical Internet traffic transported over Ethernet, the proposed ZERO tunneling protocol …