Page 1¶
Ethernet Accessories¶
ND-107760/107770/107780/107730/107720/107740/107700/107710/107750/107790/107830
![Photo: Ethernet accessories including devices and cables.]
ND
Norsk Data
[Scanned by Jonny Oddene for Sintran Data © 2021]
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Ethernet Accessories¶
Introduction¶
Norsk Data's Ethernet offers a wide range of accessories to accommodate the variety of sizes and configurations required of a Local Area Network (LAN). These accessories include cables (both coaxial and transceiver), splices, transceivers, terminators, local and remote repeaters, and Fan-Out Units. Like Norsk Data's Ethernet, these accessories all conform to the full specifications of the International Standards Committee, ISO 8802/3.
The Ethernet accessories are purchased separately when purchasing the Ethernet Controller including COSMOS Ethernet Option. Some of the accessories may be purchased later, when the customer expands their Ethernet network to accommodate growing network demands.
Cables, Splices, and Terminators¶
Coaxial cables are the most commonly-used cables in Ethernet networks. The coaxial cable forms the main bus of the LAN and the individual segments. Data Terminal Equipment (DTEs) can be connected to the cable, using a transceiver cable.
The cable used is baseband coaxial cable. This means that only digital signals are sent, and they are sent one bit at a time.
The basic coaxial cable in Ethernet consists of a central carrier wire, surrounded by two layers of alternating wire mesh and insulating material. A strong outer shield insulates the cable from the surrounding environment. It is easy to install and requires almost no maintenance.
Norsk Data's coaxial cable comes in three lengths:
| Cable Type | Length |
|---|---|
| ND 107760 Ethernet Coaxial Cable | 23.4 meters |
| ND 107770 Ethernet Coaxial Cable | 70.2 meters |
| ND 107780 Ethernet Coaxial Cable | 117 meters |
The coaxial cable has a maximum segment length of 500 meters. Beyond 500 meters, a repeater must be used to link the segments.
Splice¶
ND 107730 is an Ethernet Splice. The Ethernet Splice is used to extend segments of cable to a length of up to 500 meters.
Terminators¶
Each Ethernet segment must be terminated at both ends with a 50 ohm terminator (ND 107720). The terminators minimize reflection from the ends of the cables. At one end, the cable screen must be grounded.
Transceivers¶
Nodes or stations on the Ethernet network are connected to the coaxial cable by means of transceivers.
The Transceiver (ND 107740) provides a simple and flexible way of connecting to the Ethernet network. The transceiver has two interfaces. A drop cable interface is for the equipment, and a coaxial cable connection is for the local network. The transceiver provides communication between these interfaces, but simultaneously maintains isolation between them.
ND 107740 performs Carrier Sense and Collision Detection (CSMA/CD). The transceiver senses the carrier in a cable when someone is transmitting. It detects collisions by monitoring the electrical signal level in the cable.
Up to 100 transceivers may be placed on a cable segment, but only at spacing multiples of 2.5 meters (i.e. at 2.5 meters, 5 meters, 7.5 meters, etc.). The cable segments are marked at 2.5 meter intervals to accommodate this restriction.
Transceiver Cable¶
The transceiver cable connects a physically separate transceiver to a station/node on the Ethernet network.
The transceiver cable consists of four-stranded, twisted pair conductors, plus an overall shield and insulating jacket (as specified in Ethernet's specification DIX 2.0). It carries power and the signals for transmitting, receiving and detecting collisions.
The Norsk Data Ethernet Transceiver cable comes in two lengths:
| Transceiver Cable Type | Length |
|---|---|
| ND 107700 Ethernet Transceiver Cable | 5 meters |
| ND 107710 Ethernet Transceiver Cable | 15 meters |
A maximum of 50 meters of transceiver cable may be used between a station and its associated transceiver.
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Ethernet Accessories¶
Repeaters¶
Repeaters are devices used to extend the length and topology of a network beyond 500 meters. The current restriction is that there should be no more than two repeaters in a transmission path between any two nodes/stations.
A repeater receives signals, decodes, retimes, and regenerates them for onward transmission.
Repeaters do not have to be located at the ends of cable segments and customers are not limited to one repeater per segment. The repeaters can be used not only to extend the length of the network, but also to extend the topology from being one-dimensional to becoming three-dimensional.
A repeater requires a transceiver on each of the segments between which it is repeating signals. These transceivers must be counted toward the 100 maximum allowed.
Norsk Data offers two types of repeaters: Local and Remote Repeaters.
Local Repeaters¶
The Local Repeater Package (ND 107750) is used for Ethernet segments longer than 500 meters within the same building.
The local repeater performs functions such as regenerating preamble, extending collision fragments, automatic partitioning and reconnection of the network in the event of a segment failure. It also allows manual partitioning for segment servicing or for reconfiguration.
When ordering ND 107750, the customer receives a package of 1 repeater, 2 transceivers, and 15 meters of transceiver cable.
Remote Repeaters¶
Remote Repeaters (ND 107790) perform the same functions as the local repeaters; however, they come as a package of two, used to connect LANs between buildings.
When ordering ND 107790, the Remote Repeater Package, the customer receives 2 repeaters, 2 transceivers and 2 x 15 meters of transceiver cable.
Fiber optic cable must be ordered for the use of Remote Repeaters in multibuilding networks. It can also be ordered for Ethernet installations within one building. This cabling minimizes the interference from electrical signalling and other noise in the environment.
Fan-Out Units¶
Norsk Data sells a Fan-Out Unit (ND 107830) for providing transceiver-type connections for up to eight DTEs. Because the Fan-Out Unit can serve up to eight pieces of data processing equipment and allows for easy expansion of existing installations, it is both economic and convenient.
The Fan-Out Unit acts as a transceiver multiplexer, and thus provides the full data rate of the network to each connect drive. The connection from the Fan-Out Unit to the network is made via the transceiver.
Fan-Out Units may be connected in a series when more than eight ports are required. They may also operate in a stand-alone mode in a diameter of 100 meters.
+--------------------------+
| Coaxial Cable |
+--------------------------+
|
|
+--------------------------+
| 2.5 |
+--------------------------+
|
|
+----------------+ +----------------+
| Transceiver | | Transceiver & |--+
| |<---->| Local Repeater| |
+----------------+ +----------------+ |
|
|
+----------------+
| Coaxial Cable |
+----------------+
|
|
+----------------+
| Fiber Optic |---> Remote
| Repeater 1000m | Repeater
+----------------+
Summary¶
All of the products described in this data sheet are designed following the standards ISO 8802/3 and IEEE 802.3.
The chart below summarizes the product names and their ND numbers.
| ND Number | Product Name |
|---|---|
| 107760 | Ethernet Coaxial Cable, 23.4 meters |
| 107770 | Ethernet Coaxial Cable, 70.2 meters |
| 107780 | Ethernet Coaxial Cable, 117.0 meters |
| 107730 | Ethernet Splice |
| 107720 | Ethernet Terminator |
| 107740 | Ethernet Transceiver |
| 107700 | Transceiver Cable, 5 meters |
| 107710 | Transceiver Cable, 15 meters |
| 107750 | Local Repeater Package |
| 107790 | Remote Repeater Package |
| 107830 | Fan Out Unit Package |