Glossary - 4 WT4070/90 Wearable Terminal User Guide

H
Hard Reset. See Cold Boot.
Hz. Hertz; A unit of frequency equal to one cycle per second.
Host Computer. A computer that serves other terminals in a network, providing such services as computation,
database access, supervisory programs and network control.
I
IEC. International Electrotechnical Commission. This international agency regulates laser safety by specifying
various laser operation classes based on power output during operation.
IEC (825) Class 1. This is the lowest power IEC laser classification. Conformity is ensured through a software
restriction of 120 seconds of laser operation within any 1000 second window and an automatic laser
shutdown if the scanner's oscillating mirror fails.
IEEE Address. See MAC Address.
Interleaved 2 of 5. A binary bar code symbology representing character pairs in groups of five bars and five
interleaved spaces. Interleaving provides for greater information density. The location of wide elements
(bar/spaces) within each group determines which characters are encoded. This continuous code type
uses no intercharacter spaces. Only numeric (0 to 9) and START/ STOP characters may be encoded.
IOCTL. Input/Output Control.
Interleaved Bar Code. A bar code in which characters are paired together, using bars to represent the first
character and the intervening spaces to represent the second.
Interleaved 2 of 5. A binary bar code symbology representing character pairs in groups of five bars and five
interleaved spaces. Interleaving provides for greater information density. The location of wide elements
(bar/spaces) within each group determines which characters are encoded. This continuous code type uses
no intercharacter spaces. Only numeric (0 to 9) and START/STOP characters may be encoded.
Internet Protocol Address. See IP.
I/O Ports. interface The connection between two devices, defined by common physical characteristics, signal
characteristics, and signal meanings. Types of interfaces include RS-232 and PCMCIA.
Input/Output Ports. I/O ports are primarily dedicated to passing information into or out of the terminal’s
memory. Wearable terminals include Serial and USB ports.
IP. Internet Protocol. The IP part of the TCP/IP communications protocol. IP implements the network layer (layer
3) of the protocol, which contains a network address and is used to route a message to a different network
or subnetwork. IP accepts “packets” from the layer 4 transport protocol (TCP or UDP), adds its own header
to it and delivers a “datagram” to the layer 2 data link protocol. It may also break the packet into fragments
to support the maximum transmission unit (MTU) of the network.