Motorola ET1, Руководство интегратора

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Glossary - 6 ET1 Enterprise Tablet Integrator Guide
R
RAM. Random Access Memory. Data in RAM can be accessed in random order, and quickly written and read.
RF. Radio Frequency.
ROM. Read-Only Memory. Data stored in ROM cannot be changed or removed.
Router. A device that connects networks and supports the required protocols for packet filtering. Routers are typically
used to extend the range of cabling and to organize the topology of a network into subnets. See Subnet .
S
Scanner. An electronic device used to scan bar code symbols and produce a digitized pattern that corresponds to the
bars and spaces of the symbol. Its three main components are: 1) Light source (laser or photoelectric cell) -
illuminates a bar code,; 2) Photodetector - registers the difference in reflected light (more light reflected from
spaces); 3) Signal conditioning circuit - transforms optical detector output into a digitized bar pattern.
SDK. Software Development Kit
Shared Key. Shared Key authentication is an algorithm where both the AP and the MU share an authentication key.
SID. System Identification code. An identifier issued by the FCC for each market. It is also broadcast by the cellular
carriers to allow cellular devices to distinguish between the home and roaming service.
Space. The lighter element of a bar code formed by the background between bars.
Specular Reflection. The mirror-like direct reflection of light from a surface, which can cause difficulty decoding a bar
code.
Start/Stop Character. A pattern of bars and spaces that provides the scanner with start and stop reading instructions
and scanning direction. The start and stop characters are normally to the left and right margins of a horizontal code.
Subnet. A subset of nodes on a network that are serviced by the same router. See Router .
Subnet Mask. A 32-bit number used to separate the network and host sections of an IP address. A custom subnet mask
subdivides an IP network into smaller subsections. The mask is a binary pattern that is matched up with the IP
address to turn part of the host ID address field into a field for subnets. Default is often 255.255.255.0.
Substrate. A foundation material on which a substance or image is placed.
Symbol. A scannable unit that encodes data within the conventions of a certain symbology, usually including start/stop
characters, quiet zones, data characters and check characters.
Symbol Aspect Ratio. The ratio of symbol height to symbol width.
Symbol Height. The distance between the outside edges of the quiet zones of the first row and the last row.
Symbol Length. Length of symbol measured from the beginning of the quiet zone (margin) adjacent to the start
character to the end of the quiet zone (margin) adjacent to a stop character.