Nortel Networks NN43001-314 - Manual (Page 412)

412 List of terms
same conference even though they are using different videoconferencing
applications. Although most videoconferencing 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.
ITG-P
The ITG-Pentium card has a Pentium processor and 24 Digital Signal
Processor (DSP) channels. It occupies two slots in an MG 1000B Core or
MG 1000B Expander. It provides the same functionality as the Media Card
when equipped with the IP Line 3.1 application. See Voice gateway.
LAN
Local Area Network.
Layer 2 switching
Packets are forwarded according to the destination’s MAC address. The
switch automatically determines which switch port must be used to send
the packet, according to the destination’s MAC address. The MAC address
location was determined from incoming packets from that MAC address
received on that port.
Layer 3 switching
Packet traffic is grouped according to the source and destination addresses.
The first packet in a flow is routed by a software-based algorithm.
Subsequent packets with the same source and destination addresses
are switched according to the destination’s MAC address (hardware
mechanism). This is similar to multi-layer routing and routers with hardware
assist.
NAT
Network Address Translation. It is defined as an internet standard that lets a
LAN use both internal and external IP addresses. This protects an internal
IP address from being accessed from outside. NAT translates the internal
Nortel Communication Server 1000
Branch Office Installation and Commissioning
NN43001-314 01.02 Standard
Release 5.0 20 June 2007
Copyright © 2007, Nortel Networks
.