Polycom EX Manual De Usuario
Chapter 4 - Installing Videoconferencing Systems
© Polycom, Inc.
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If You Are Connecting to a PBX
❑
Some PBXs require a crossover cable.
❑
The PBX must provide the clock signal and act as the network
side for layers 1, 2, and 3.
side for layers 1, 2, and 3.
❑
QSIG signaling (PSS1) is not supported. However, a PRI
network interface module can be connected to a PISN through a
gateway using ETSI DSS1 signaling.
network interface module can be connected to a PISN through a
gateway using ETSI DSS1 signaling.
Cables Used with the PRI Network Interface Module
The following cables may be used with the PRI network interface
module.
module.
❑
Peripheral link cable:
The peripheral link cable does not fit into
a standard RJ-45 network port. You can, however, use it to
connect any Polycom network interface module to the system.
connect any Polycom network interface module to the system.
❑
PBX crossover cable:
An RJ-45 crossover cable may be required
when connecting the PRI network interface module to a PBX or
other third-party network access device.
other third-party network access device.
❑
PRI Cable extension
: You can purchase a cable adapter kit to
extend the distance between your system and the PRI network
interface module.
interface module.
❑
75
Ω
coaxial adapter:
The PRI E1 line termination is 120
Ω
. In
some areas, however, the E1 network connection is via a 75
Ω
coaxial cable. The PRI network interface module does not
directly support this, but you can obtain passive adapter
devices from various vendors.
directly support this, but you can obtain passive adapter
devices from various vendors.