Ethernet connection

If the PC is connected directly to the coaxial cable of an Ethernet LAN, the PC can be used in the same modes described above, but with the much higher transmission speed of the Ethernet. A higher level of network protocol, however, has to be applied, e.g. DECnet-DOS, Novell-NetWare, or similar products. Because of the high speed of the Ethernet connection more sophisticated modes of PC operations can be implemented. 

In both of these modes the PC user has transparent access to other resources of the network as well, like printers and special peripherals. Since the PC s hard disk in reality is physically part of the server s disk, it is included in the normal backup/ restore procedures that are in use on the server system. If several users share the 

By the tight integration of PCs into a network with a variety of resources most of the shortcomings of PCs described in an earlier paragraph will be overcome. 

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MAXI loot LAN Ethernet connectivity module N/A Ethernet... 

An NMR experiment is carried out as follows we select an experiment to run. We tell the NMR software on the host computer (the computer attached directly to the NMR instrument) what experiment we want to run, and the computer sends the appropriate set of instructions to the computer built into the NMR console. The two computers most often communicate via an Ethernet connection. The host computer will have a second Ethernet card dedicated to talking to the NMR console computer. These instructions will include ... 

Console computer. The computer built into the NMR console (usually one or two 19" wide electronics racks). The console computer normally communicates via an Ethernet connection with the host computer, which is the computer the NMR operator uses to initiate experiments, etc. 

Ethernet connection. The link between two or more digital devices through their respective Ethernet cards. 

At the lowest level, the aetwork is the physical medium that connects the various pieces of equipmeat. This can be copper wire, often known as Ethernet, or optical fiber, ie, fiber-distributed data iaterface (EDDI). Networks allow transmission of data at nominal speeds of 10 to 100 megabits per second, depending on the physical medium used. 

The experimental facility is a pilot-scale distillation column connected to an industrial ABB MOD 300 distributed control system, which in turn is connected to a VAX cluster. The control system consists of a turbo node (configuration, history, console) remote I/O, and an Ethernet gateway, which allows communication with the VAX-station cluster through the network. This connection allows time-consuming and complex calculations to be performed in the VAX environment. Figure 10 shows the complete setup. 

Development Environment. Hardware the hardware currently consists of a Symbolics 3670 workstation, a Symbolics 3640 workstation, and a VAX 750, all connected by Chaosnet (an Ethernet prote-... 

Two Bruker DRX-spectrometers, each connected to a INDY-workstation (INDY WS) use FTP to communicate and exchange data files via a thin-wire Ethernet with a SUN workstation, acting as a bridge to the central network (thick-wire Ethernet). FTP is used to send data from both DRX spectrometers via the bridge to the central server workstation (SERVER WS). 

Two Bruker AC spectrometers are connected to a Bridge-PC using NMRLINK. These two PCs are also connected to the central network (thick-wire Ethernet) and exchange data with the central Server Workstation using FTP. A series of PCs, located in laboratories and serving as remote NMR processing stations, are connected via the central network to the central Server Workstation. Most of these remote PCs use NFS for transferring NMR data. Since this communication is restricted to the transfer of NMR data from the central Server to the PC no passwords are required. 

Positioning systems can use a network communication configuration, where the components operate as nodes on a network. Network communications protocols include ARCnet, CANbus, DeviceNet (a version of CANbus), Ethernet, PROFIBUS, IEEE 1394 (FireWire), IEEE 1451, Interbus-S, SERCOS, and Seriplex, among others. PC bus-type protocols include the normal backplane ISA/EISA (PC-XT/AT) connection for a PC, MAC PCI (Nubus) for Macintosh computers, Multibus, PC 104, PCI bus, cPCI bus (compact PCI), PCMCIA, VME bus, and VXI. 

Today, coaxial cable with baseband transmission is the most frequently used technique in implementations of LANs, in Ethernet LANs as well as in token ring networks. Transmission rates are mostly between 6 and 16 Mbits/s. Interfacing to coaxial cable is rather simple, especially with Ethernet new nodes can be connected to an existing cable without interrupting the operation of the network. 

Ethernet media can be divided into two general configurations or topologies bus and point-to-point. These two topologies define how nodes are connected to one another. A node is an active device connected to the network, such as a computer or a piece of networking equipment, for example, a repeater, a bridge, or a router. 

A UTP, or 10 BaseT Ethernet, is realized with a point-to-point topology. Generally a computer is located at one end of the segment and the other end is terminated in a central location with a repeater or hub. Since UTP is often run in conjunction with telephone cabling, this central location can be a telephone closet or other area where it is convenient to connect the UTP segment to a backbone. UTP segments are limited to 100 meters, but UTPs point-to-point nature allows the rest of the network to function correctly if a break occurs in a particular segment. 

Transceivers are used to connect nodes to the various Ethernet media. Transceivers, also known as Media Attachment Units (MAUs), attach to the Ethernet cable and provide an Application User Interface (or AUI) connector for the computer. The AUl connector consists of a 15-pin D-shell type connector, female on the computer side and male on the transceiver side. Virtually all Ethernet-compatible computers provide such an AUI connector. The transceiver is generally attached directly to the computer s AUI connector, or the transceiver may be attached to the computer with a specially shielded AUI cable which must be less than 50 m long. In addition to an AUI connector, many computers also contain a built-in transceiver, allowing them to be connected directly to Ethernet without requiring an external transceiver. 

Repeaters also monitor all connected segments for basic characteristics necessary for an Ethernet to run correctly. When these conditions are not met on a particular segment, for example when a break occms, aU segments in an Ethernet may become inoperable. 

Occasionally, networks use RS-232 cables (also known as serial cables) to carry data. The most classic example is in older mainframe and minicomputer terminal connections. Connections from the individual terminals go to a device known as a multiplexer that combines the serial connections into one connection and connects all the terminals to the host computer. This cabling system is seen less and less as a viable TAN cabling method, however, because LAN connections (like twisted-pair Ethernet) are faster, more reliable, and easier to maintain. 

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