Proximus Forum 500 Series, Руководство по монтажу и пусконаладке

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Point-to-Point Connection Lines
PBX Networking 231
When applying the L1 clock of trunk lines, you can assume that the public
network is “clock-aligned”. So, in the above example, you can connect
additional trunk lines to one of the PBXs.
Point-to-Point Connection Lines
There are different types of lines available for a point-to-point connection
between two PBXs, depending on the distance between them.
Direct Connection
This type of ISDN point-to-point connection joins the two systems directly to
each other using a crossover twisted-pair cable. An S
0
connection can be used
for distances up to 1,000 metres. Normally one PBX is the protocol master for
all three layers, and the other PBX is the protocol slave for all three layers.
Direct connection
Use the RJ45 jacks on one of the external S
0
ports for an S
0
connection
between two Forum 5004/5008/5012s.
The external S
0
-ports of a gateway can also be used for a direct connection.
Connection via an Active Transmission System
For distances exceeding the range of a direct connection, an active
transmission system can increase the range to up to 50 km. Normally the L1
master is the transmission system for the two connected PBXs. For the
protocol layers L2 and L3, one PBX is normally the protocol master and the
other PBX is the protocol slave.
Connection by an active transmission system
PBX 1
L1 master
L2 master
L3 master
PBX 2
L1 slave
L2 slave
L3 slave
PBX 1
L1 slave
L2 master
L3 master
PBX 2
L1 slave
L2 slave
L3 slave
Transmission
System
L1 master