User`s manual

Appendix A - Glossary User’s Manual (SIP/MGCP Version)
AT-VP504E FXS 17
Light Emitting Diode
(LED)
A semiconductor diode that emits light when a current is passed
through it.
Local Area Network
(LAN)
Data-only communications network confined to a limited geographic
area, with moderate to high data rates. Contrast with WAN.
Network A group of two or more computer systems that are linked.
Off-hook A line condition caused when a telephone handset is removed from its
cradle.
On-hook A line condition caused when a telephone handset is resting in its
cradle.
Packet Group of bits transmitted as a complete package on a packet-switched
network.
Port Network access point, the identifier used to distinguish among multiple
simultaneous connections to a host.
Private Branch
Exchange (PBX)
A small to medium sized telephone system and switch that provides
communications between onsite telephones and exterior
communications networks.
Protocol Defines a common set of rules and signals that computers on the
network use to communicate.
Public Switched
Telephone Network
(PSTN)
The local telephone company network that carries voice data over
analog telephone lines.
Server A computer or device on a network that works in conjunction with a
client to perform some operation, for example a Windows NT Server.
Session Initiation
Protocol (SIP)
SIP is a simple signaling protocol for Internet conferencing and
telephony.
Single Network
Monitor Protocol
(SNMP)
SNMP is the protocol governing network management and the
monitoring of network devices and their functions.