Search results for "ether"
showing 10 items of 986 documents
An evaluation of switched ethernet and linux traffic control for real-time transmission
2008
Switched Ethernet networks are spreading to industrial environments more are more. The current trend is using them at all levels of a factory, replacing this way field-buses and other industrial networks. Switched Ethernet lacks the drawback of the non-deterministic collision resolution of coax cabling. However there are still some sources of indeterminism, mostly due to contention problems in message queues at switches and network interfaces. These problems can be dealt with using traffic control mechanisms for packet prioritisation and scheduling. These features have been largely inaccessible in Ethernet for a long time but, nowadays, they are widely available in industrial switches and a…
A new preprocessing and control board for the phase 2 electronics of AGATA experiment
2016
The electronics of AGATA HPGe segmented gamma ray detector faces a new challenge in the search of a bigger integration and cost reduction for the phase 2 of the experiment going beyond 45 crystals. This opportunity can be used to introduce a new architecture based on commercial standards while keeping backward compatibility with current electronics. In this sense, new FPGA devices and fast Ethernet links can be used to ease the preprocessing and control task and allowing for processor farms to distribute the processing load. At the same time, modularity should be a key feature of the design in the aim to make it upgradable in time and technology. This paper presents the design of a new prep…
The upgraded HADES trigger and data acquisition system
2011
The HADES experiment is a High Acceptance Di-Electron Spectrometer located at GSI in Darmstadt, Germany. Recently, its trigger and data acquisition system was upgraded. The main goal was to substantially increase the event rate capability by a factor of up to 20 to reach 100 kHz in light and 20 kHz in heavy ion reaction systems. The total data rate written to storage is about 400 MByte/s in peak.In this context, the complete read-out system was exchanged to FPGA-based platforms using optical communication. For data transport a general-purpose real-time network protocol was developed to meet the strong requirements of the system. In particular, trigger information has to reach all front-end …
Nanoseconds Timing System Based on IEEE 1588 FPGA Implementation
2019
Clock synchronization procedures are mandatory in most physical experiments where event fragments are readout by spatially dislocated sensors and must be glued together to reconstruct key parameters (e.g. energy, interaction vertex etc.) of the process under investigation. These distributed data readout topologies rely on an accurate time information available at the frontend, where raw data are acquired and tagged with a precise timestamp prior to data buffering and central data collecting. This makes the network complexity and latency, between frontend and backend electronics, negligible within upper bounds imposed by the frontend data buffer capability. The proposed research work describ…
Integration of IEC 61850 MMS and IEEE 802.22 for Smart Grid Communication
2017
The reliability of Smart Grid depends on two-way communication between substation and utility. IEC 61850 is an international standard defined to ensure interoperability between Substation Automation System (SAS). IEC 61850 services are mapped on the Manufacturing Message Specification (MMS) especially for meter data management system. MMS is the OSI protocol that run over TCP/IP or OSI networks to support IEC 61850 services. Presently, the MMS uses Ethernet as the layer 2 protocol. However, for long distance communication in remote areas wireless communication is the prefered mode. The Cognitive Radio based IEEE 802.22 is next generation standard for Wireless Regional Area Network (WRAN) th…
Review of IEEE 802.22 and IEC 61850 for real-time communication in Smart Grid
2015
Real time data communication in Smart Grid is a big challenge due to its vastness and complexities. Wireless Regional Area Network (WRAN) - IEEE 802.22 permits opportunistic use of television white space (TVWS) by secondary user, if it is not being utilized by primary user. This standard has the potential to transfer big data of smart grid in real time to control center. The IEC 61850 is the standard for electrical substation automation that uses TCP/IP for data transfer among different ‘intelligent electronic devices’ (IEDs). IEC 61850 consists of different message types which belong to different performance classes that are mapped to different communication protocols. The different perfor…
Design of an exact data deduplication cluster
2012
Data deduplication is an important component of enterprise storage environments. The throughput and capacity limitations of single node solutions have led to the development of clustered deduplication systems. Most implemented clustered inline solutions are trading deduplication ratio versus performance and are willing to miss opportunities to detect redundant data, which a single node system would detect. We present an inline deduplication cluster with a joint distributed chunk index, which is able to detect as much redundancy as a single node solution. The use of locality and load balancing paradigms enables the nodes to minimize information exchange. Therefore, we are able to show that, …
Gigabit Ethernet backbones with active loops
2001
The current standard Ethernet switches are based on the Spanning Tree (ST) protocol. Their most important restriction is that they can not work when the topology has active loops. In fact, the ST protocol selects a tree from the real topology by blocking the links that are not involved in the tree. This restriction produces a network traffic unbalancing behavior saturating those link near the root switch while rest of links will be idle or with a very low utilization. This paper proposes a new transparent switch protocol for Gigabit Ethernet backbones that considerably improves the performance of current ones. The proposed protocol is named ALOR for Active Loops and Optimal Routing. ALOR pr…
A fault-tolerant protocol for railway control systems
2006
Railway control systems are largely based on data communication and network technologies. With the adoption of Ethernet-IP as the main technology for building end-to-end real-time networks on railway control systems, the requirement to deliver high availability, quality and secure services over Ethernet has become strategic. Critical real-time traffic is generally penalized and the maximum restoration time of 50 msec sometimes is exceeded because of real-time applications hangings, so passengers' safety could be committed. It occurs on more than twenty percent of critical fail tests performed. Our main goal is to minimize restoration time from the application point of view. This article des…
The JYFLTRAP control and measurement system
2008
The JYFLTRAP setup has been used for precision mass spectrometry since 2003. An essential part of this setup is the computer-controlled system consisting of software and hardware that is required to operate the instruments. The software has been developed solely at JYFL using LabVIEW and C++ development tools. The hardware consists of devices controlled using Control Area Network (CAN) field bus and Ethernet for communication purposes. LAN/GPIB-gateways, modular multichannel ISEG DC power supplies and WAGO I/O systems are also used.