Bosch DHR-1600A-150A, Глоссарий

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en | Glossary of CCTV Terms Camera, DVR, and VIP products
AR18-08-B000 | | Version 1.0 | 2008.08 Glossary of CCTV Terms Bosch Security Systems
iSCSI Internet Small Computer System Interface: Protocol that manages storage via a TCP/IP
network. iSCSI enables access to stored data from everywhere in the network.
ISDN Integrated Services Digital Network: Comprised of digital telephony and data-transport
services offered by regional telephone carriers. ISDN involves the digitization of the telephone
network, which permits voice, data, text, graphics, music, video, and other source material to
be transmitted over existing telephone wires.
J
JPEG Joint Photographic Experts Group: The name of the committee that created a standard for
encoding still images.
K
kBit/s Kilobits per second: The actual data rate.
L
LAN
Local Area Network:
A communications network serving users within a limited geographical
area, such as a building or a university campus. It is controlled by a network operating system
and uses a transfer protocol.
LUN Logical Unit Number: Logical drive in iSCSI storage systems.
Lux The International System Unit (
see
SI) of measurement of the intensity of light. It is equal to
the illumination of a surface one meter away from a single candle.
M
MAC Media Access Control: A quasi-unique identifier attached to most network adapters (NICs). It
is a number that acts like a name for a particular network adapter.
MIB Management Information Base: A collection of information for remote servicing using the
SNMP protocol.
MJPEG Motion JPEG is a digital video encoding standard where each video frame is separately
compressed into a JPEG image.
Modal Dispersion A broadening of a waveform over long distances. Modal Dispersion (or Intermodal Dispersion)
occurs in multimode fibers, because light is bounced down different reflective paths (e.g.
modes) in the fiber. As the distance increases, the path (mode) begins to spread and the
arrival time for the different light rays begins to vary. A large variance (dispersion) increases
the chance that the optical receiver may interpret the incoming signals incorrectly. Modal
dispersion is a major problem with multimode fibers.
MPEG-4 A further development of MPEG-2 designed for transmitting audiovisual data at very low
transfer rates (for example over the Internet). A digital video encoding and compression
standard that uses interframe encoding to significantly reduce the size of the video stream
being transmitted. With interframe coding, a video sequence is made up of keyframes that
contain the entire image. In between the keyframes are delta frames, which are encoded with
only the incremental differences. This often provides substantial compression because in
many motion sequences, only a small percentage of the pixels are actually different from one
frame to another.