Bosch DHR-1600A-150A, Глоссарий

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Camera, DVR, and VIP products Glossary of CCTV Terms | en
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Bosch Security Systems Glossary of CCTV Terms AR18-08-B000 | | Version 1.0 | 2008.08
Multimode Fiber An optical fiber with a larger core (typically 50 or 62.5 microns) than singlemode fiber (
see
Singlemode Fiber). The core is made of plastic or glass fibers. It is the most commonly used
fiber for cabling short distances as used in LANs. The name multimode comes from the fact
that light rays travel down multiple reflective paths (modes) within the fiber. This allows light
to enter the core at different angles, making it easier to connect to broader light sources such
as LEDs (light emitting diodes). Fiber optic interfaces and multimode fiber-based
transmission systems are less expensive than those based on singlemode fiber. However, the
use of multiple reflective paths (modes) increases modal dispersion (
see
Modal Dispersion)
and shortens the distances that this type of fiber optic transmission system can span.
Multi-Protocol A convention or standard that controls or enables the connection, communication, and data
transfer between two devices. In PTZ cameras, such as the AutoDome and Pan/Tilt units,
protocol refers to the standard used to control the pan, tilt, and zoom (PTZ) operation of the
camera. Since each camera manufacturer’s PTZ protocols are unique, multi-protocol support
is needed to support third party systems. AutoDome cameras support the Pelco D and P
protocols as well as Bosch’s own Biphase protocol (
see
Biphase). The Pan/Tilt units support
the Pelco “D” protocol as well as Bosch’s own Biphase and Bilinx protocols (
see
Bilinx).
N
NEMA Rating Electrical Standards and Publications published by NEMA (National Electrical Manufacturers
Association). Specification standards in reference to the operating environment for a variety
of electrical devices.
Net mask A mask that explains which part of an IP address is the network address and which part is the
host address. It is usually written in dotted decimal notation, for example 255.255.255.192
(
see also
Subnet Mask).
NightSense A method of boosting the sensitivity of high-resolution Bosch color cameras by 9 db (a factor
of 3) by combining the signal of the color image in a single monochrome picture.
NPT National Pipe Thread: A U.S. standard for tapered threads. NPT sizes measure the nominal
inside diameter of the pipe. NPT threads form a seal as the threads compress against each
other.
NTP Network Time Protocol: A standard for synchronizing computer system clocks via packet-
based communication networks. NTP uses the connectionless network protocol UDP (
see
UDP). This was developed specifically for enabling time to be reliably transmitted over
networks with variable packet runtime (Ping).
O
OSD On-screen Display: Menus are shown on the display monitor.
P
Pan Camera movement in the horizontal direction.
Parameters Values used for configuration.
Pixel The smallest addressable unit on a display screen or bitmapped image.
Port 1) On computer and telecommunication devices, a port (noun) is generally a specific place for
being physically connected to some other device, usually with a socket and plug of some kind.