Quantum Scalar i40, User Manual

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Quantum Scalar i40 and Scalar i80 User’s Guide 287
Glossary
Numerals
1U, 2U, 3U, etc. Racks manufactured for mounting computer
hardware often define vertical space as “units.” The
components that are mounted in the racks are defined by how
many units of rack space they require. For example, the height
of a unit in a rack is 1.75 inches. If a component is 5.25 inches in
thickness, the component is said to be a 3U component.
A
Arbitrated loop A Fibre Channel configuration that attaches multiple
communicating ports in a loop. Two or more ports can
interconnect, but only two ports can communicate
simultaneously.
Arbitration The submission of a request to gain access to an
arbitrated loop by a device, so that it can transmit data in the
loop.
B
Barcode A printed array of varied rectangular bars and spaces that can
be scanned and read for object identification.
Bus A transmission channel through which electrical signals are
carried from one device to another device.