ICP DAS USA VERION 1.0 MSM-508FCS - Manual (Page 36)

Industrial Ethernet Layer 2 Managed Switch User Manual
TDRS4050601 a
Appendix A
Glossaries
ANSI X3T9 Commonly referred to as FDDI. A local area network protocol that operates at
100Mbps.
Asynchronous Having a variable time interval between successive data or information in the form
of characters, operations, events. Transmission in which the data or information is
individually synchronized or timed usually by start and stop bits (S/S).
Attenuation A general term describing the loss of power between two points, measured in
decibels per kilometer (dB/km) at a specified wavelength (nm).
Backbone Network A main or high speed transmission facility or medium usually designed to connect
lower speed channels or clusters of terminals. May describe common carrier main
transmission path.
Bandwidth A range of frequencies available for signaling; the differences between the highest
and lowest frequencies of a band are expressed in (Hz).
Bridge A device used to connect two separate LANs or used to divide a large LAN into
smaller LANs. Each LAN acts as its own LAN, but uses a bridge device to
communicate from one LAN to another.
Bus Path or channel, usually electrical, with one or more conductors, where all devices
are able to receive all transmissions at the same time.
Counter-Rotating
Ring Aka. Self-Healing Ring; has two physical transmission lines or rings with
transmitting and receiving signals in each ring travelling in opposite directions. If the
line or a device along the ring fails, the ring re-anneals by bypassing the device and
or line and forms with the other ring to form a new single ring.
Crosstalk The unwanted transfer of energy from the disturbing circuit to another called the
disturbed circuit. Usually from an adjacent analog channel.
Dispersion The spreading of light pulses that takes place in multimode fiber optic transmission.
Dispersion limits the potential transmission distance because the spread out light
pulses reach the destination at different times making the signal unreadable.
Ethernet Product name for one of the first popular LAN technologies, later standardized as
IEEE 802.3.
Fiber Optic Cable Thin filaments of glass or other transparent material sheathed in an insulator
through which a light beam may be transmitted for long distances by means of
multiple internal reflections. A waveguide used to transmit digital information.
Flow Control A method for a receiver to control the information flow from a transmitter. It
eliminates data overflow at the receiver.
Full Duplex A communication method where both ends can transmit and receive
simultaneously.
Half Duplex A communication method where one end transmits while the other end receives,
then reverses the process.