Nortel 1000 Configuration Manual page 214

214 List of terms
special manner, or who wants to be notified when a telephone user makes
an emergency call. It would also appeal to a customer who wishes to have
ESA calls answered on-site,
on the business premises, rather than being forwarded to the Public
Services Answering Point (PSAP). See Emergency Services Access
Fundamentals (NN43001-613) for complete information.
Gatekeeper
The Gatekeeper is a separate application on an IP network that directs
IP traffic to all the systems on the network. Parameters for both the main
office and SRG must be assigned to all gatekeepers active on the network.
If the Gatekeeper is down, the SRG attempts to connect to the Alternate
Gatekeeper, if there is one. If the Alternate Gatekeeper is down as well, or
there is no Alternate Gatekeeper, the SRG IP Phones remain registered
with the main office but calls cannot be sent to the SRG.
gateway
In networking, a combination of hardware and software that links two
different types of networks. Gateways between e-mail systems, for example,
enable users on different e-mail systems to exchange messages.
H.323
A standard approved by the International Telecommunication Union (ITU)
that defines how audiovisual conferences data is transmitted across
networks. In theory, H.323 enables users to participate in the same
conference even though they are using different video conferencing
applications. Although most video conferencing vendors have announced
that their products conform to H.323, it is too early to say whether such
adherence actually results in interoperability.
IP
Abbreviation of Internet Protocol, pronounced as two separate letters. IP
specifies the format of packets, also called datagrams, and the addressing
scheme. Most networks combine IP with a higher-level protocol called
Transport Control Protocol (TCP), which establishes a virtual connection
between a destination and a source.
IP by itself is something like the postal system. It enables you to address a
package and drop it in the system, but there's no direct link between you
and the recipient. TCP/IP, on the other hand, establishes a connection
between two hosts so that they can send messages back and forth for
a period of time.
LAN
Local Area Network.
Copyright © 2005-2007, Nortel Networks
.
Nortel Communication Server 1000
Main Office Configuration Guide for SRG 50
NN43001-307 02.02 Standard
Release 5.0 3 December 2007