User's Manual

Glossary
4Motion 915 System Manual
ETSI European Telecommunications Standards Institute. A non-profit organization
producing voluntary telecommunications standards used throughout Europe, some
of which have been adopted by the EC as the technical base for Directives or
Regulations.
FA Foreign Agent. A mobility agent on the foreign network that can assist the mobile
node in receiving datagrams delivered to the care-of address. (The foreign network
is the network to which the mobile node is attached when it is not attached to its
home network, and on which the care-of-address is reachable from the rest of the
Internet). See also HA (Home Agent).
FCC Federal Communications Commission. A U.S. government agency that supervises,
licenses, and controls electronic and electromagnetic transmission standards.
FEC Forward Error Correction. A method of communicating data that can corrects errors
in transmission on the receiving end. Prior to transmission, the data is put through a
predetermined algorithm that adds extra bits specifically for error correction to any
character or code block. If the transmission is received in error, the correction bits
are used to check and repair the data.
FFT Fast Fourier Transform. An algorithm for converting data from the time domain to the
frequency domain; often used in signal processing.
FTP File Transfer Protocol. A protocol for exchanging files over the Internet. FTP uses the
Internet's TCP/IP protocols to enable data transfer.
GMT Greenwich Mean Time. On January 1, 1972, GMT was replaced as the international
time reference by Coordinated Universal Time (UTC), maintained by an ensemble of
atomic clocks around the world.
GPS Global Positioning System. A system that uses satellites, receivers and software to
allow users to determine their precise geographic position.
GRE General Routing Encapsulation. A method or technique of adding an IP standard
header and trailer to a message that does not follow IP protocols. The encapsulated
message is sent over a public network while received messages are stripped of the
wrapper and processed. This permits non-standard data and totally encrypted
messages to use the Internet. The technology is an important element in Virtual
Private Network (VPN) offerings.
HA Home Agent. A node on the home network (the network at which the mobile node
seems reachable, to the rest of the Internet, by virtue of its assigned IP address) that
effectively causes the mobile node to be reachable at its home address even when
the mobile node is not attached to its home network.
HARQ Hybrid Automatic Repeat reQuest (Hybrid ARQ) is a sheme wherein information
blocks are encoded for partial error correction at receiver and additional, uncorrected
errors are retransmitted.
HO Hand-Over.
HP Abbreviation for "Horizontal Pitch" or standard width measurement which defines the
width for plug-in modules in the 19” construction system. One HP equals 5.08 mm.