Chapter 15: Appendix

[4]Other Ethernet Specifications

(1)10BASE2

10BASE2 is a connection method for creating an Ethernet network using a coaxial cable approxi- mately 5 mm thick (This cable is also called a "Thin cable"). The "10" in "10BASE2" refers to a data transfer speed of 10Mbps. The word "BASE" means that the data transfer system is a "base band system." Finally, the "2" means that the data transfer distance of a trunk is limited to 185 m (approx. 200 m). In order to connect devices such as a personal computer, a T-branch BNC connector is connected to each device, and a coaxial cable comes in on each side of the T. The figure below shows a configuration example of a 10BASE2 Ethernet system.

Coaxial cable [RG58A/U] (maximum cable length: 1850 m)

Branch

Termination

connector

resistor

A configuration example of a 10BASE2 Ethernet system

(2)Optical Ethernet Specifications

Optical Ethernet is a connection method for creating an Ethernet network using an optical fiber cable to transfer data. It can be used for distances over 500 m and in systems that must be immune to noise. The following standard (IEEE802.3) connection methods are available: 10BASE-FP, 10BASE- FB, 10BASE-FL, 10BASE-FX,1000BASE-LX, and 1000BASE-SX. The figure below shows a con- figuration example of an optical Ethernet system.

10BASE5 system

Optical

Optical fiber cable

transceiver

(maximum cable length: 2 km)

Optical repeater

An example of an optical Ethernet configuration

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