Optibase MGW 2400 WMT - Manual (Page 138)

Appendix D • Glossary of Terms
Color Noise – Random interference in the color portion of a
composite video system. Because of reduced color bandwidth
or color subsampling, color noise appears as relatively long
streaks of incorrect color in the image.
Collision – A collision is an Ethernet event occurring when two
Ethernet frames collide. This may happen since every host can
transmit the moment it has something to transmit. Therefore
two hosts may transmit at the same time causing a collision.
Collision Plane – A collision plane is a bus or a wire where
collisions can take place in networks.
Composite Video – A color video signal that contains all of the
color information in one signal. Typical composite television
standard signals are NTSC, PAL, and SECAM.
Compression – A digital process that allows data to be stored
or transmitted using less than the normal number of bits. Video
compression techniques reduce the number of bits required to
store or transmit images.
Contrast – The contrast of a picture describes the difference
between light and dark. In a picture with high contrast the
transition from dark to light is very clear.
D1 – A format for recording digital video based on the ITU-R
601 standard. The term is also used to describe the resolution of
a digital video stream in comparison to the CCIR-601
resolution, for example D1 or Half D1.
Datalink Layer – Layer II in OSI Systems, This layer assures
the flow of information in the network.
Data Rate – The speed of a data transfer process, normally\
expressed in bits per second or bytes per second (e.g. the data
rate of CD-ROM is 1.2 Mbps).
Data Transfer Rate – The transfer rate of the storage media
itself. For example, the maximum data transfer rate of a CD-
ROM is 1.2 MB.
Default Gateway – The Default Gateway is a routing device
that receives all packets being sent to destination addresses
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