Viewstation Sp User Guide - Polycom ViewStation SP128 User Manual

ISP
IMUX
IP
IP Precedence
ISDN

ViewStation SP User Guide

Internet Service Provider.
Inverse Multiplexer. Equipment that
combines 64Kbps channels and presents
them to the user's terminal equipment as if
they were a single larger bandwidth channel.
Internet Protocol. An IP address is a number
that identifies a computer connected to the
Internet. Every computer that is connected to
the Internet must have unique IP address.
Currently, an IP address consists of four
sections separated by periods. Each section
contains an 8-bit value represented as a
number ranging from 0 to 255. The
allocation of these IP addresses follows a
two-level architecture that assigns IP
numbers to a network and the hosts on that
network.
IP precedence tells downstream networking
equipment (mainly routers) to give priority to
audio and video data. It marks each audio
and video packet with a user defined
precedence (the default is 4). Only audio,
video and far end camera control packets
are marked. Control packets (such as
opening and closing of connections,
channels, etc.) are not marked with
precedence.
The user may specify any one of 8 levels
(0-7) of precedence with 0 signifying no
priority and 7 signifying the highest priority.
It is recommended by networking equipment
vendors to use 4 for multimedia data. By
default, IP precedence is disabled by most
routers and is not enabled on the Internet.
Integrated Services Digital Network. Fully
digital telephony service, available at 128
166
Glossary
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