Appendix D - Glossary
Administration Manual (H.323 Version)
AT-VP504E FXO
95
Dual-Tone Multi-
Frequency (DTMF)
In telephone systems, multi-frequency signaling in which a standard
set combinations of two specific voice band frequencies, one from a
group of four low frequencies and the other from a group of four higher
frequencies, are used. Although some military telephones have 16
keys, telephones using DTMF usually have 12 keys. Each key
corresponds to a different pair of frequencies. Each pair of frequencies
corresponds to one of the ten decimal digits, or to the symbol “#” or “*”,
the “*” being reserved for special purposes.
Dynamic Host
Configuration
Protocol (DHCP)
TCP/IP protocol that enables PCs and workstations to get temporary
or permanent IP addresses (out of a pool) from centrally-administered
servers.
Electronically
Erasable
Programmable Read
Only Memory
(EEPROM)
A read only memory device that can be erased and reprogrammed.
Typically, it is reprogrammed electronically (not electromagnetically)
with ultraviolet light.
Erasable
Programmable Read
Only Memory
(EPROM)
EPROM is a special type of memory that retains its contents until it is
exposed to ultraviolet light. The ultraviolet light clears its contents,
making it possible to reprogram the memory. To write to and erase an
EPROM, you need a special device called a PROM programmer or
PROM burner.
Federal
Communications
Commission (FCC)
U.S. government regulatory body for radio, television, and interstate
telecommunications services and international services originating in
the United States.
Foreign Exchange
Office (FXO)
A network-provided service in which a telephone in a given local
exchange area is connected, via a private line, to a central office in
another, i.e., “foreign”, exchange, rather than the local exchange
area’s central office. A FXO line is normally directly connected to a line
from the telephone central office.
G.711 ITU-T recommendation for an algorithm designed to transmit and
receive A-law PCM (Pulse Code Modulation) voice at digital bit rates of
48, 56, and 64 kbps. It is used for digital telephone sets on digital PBX
and ISDN channels.
G.723.1 A Codec that provides the greatest compression, 5.3 kbps or 6.3 kbps;
typically specified for multimedia applications such as H.323
videoconferencing.
Summary of Contents for AT-VP504E FXS
Page 1: ...AT VP504E FXO H 323 Administration Manual PN 990 11592 10 Rev C VoIPTalk...
Page 16: ...Chapter 1 Introducing the AT VP504E FXO Administration Manual H 323 Version AT VP504E FXO 8...
Page 76: ...Chapter 5 Software Upgrade Administration Manual H 323 Version AT VP504E FXO 68...
Page 100: ...Appendix C Gatekeeper Registration Logic Administration Manual H 323 Version AT VP504E FXO 92...
Page 112: ...Index Administration Manual H 323 Version AT VP504E FXO 104...
