Types Of Point-To-Point; Connection - DETEWE OpenCom 130 Mounting And Commissioning Manual

When planning a PBX networking
scheme, you must make sure that
the L1 clock propagates from a mas-
ter via a number of PBXs.
Network
operator
M
Example: propagation of the L1 clock
If more than one port with the set-
ting L1 Type = "Slave" is configured
on an OpenCom 130 and the setting
L1 sync possible has been activated,
then one of the ports is automati-
cally defined as the L1 clock source.
The OpenCom 130 will automatically
switch the clock source to another
port configured as an L1 clock source
(if a line fails, for example).
Please note: Reciprocal or circu-
lar application of the L1 clock is not
allowed.
Example: In the above case you
could reverse the L1 slave/master
setting for the connection between
PBX 1 and PBX 3. However, if you
then activate the setting
L1 sync possible for the port of PBX
1, this may cause parts of the PBX
network to stop functioning tempo-
rarily.
When applying the L1 clock of trunk
lines, you can assume that the public
network is "clock-aligned". So, in the
80
PBX Networking
PBX1 PBX 3
S M S
M S
S
Trunk line
Point-to-point
PBX 2
M

connection

above example, you can connect ad-
ditional trunk lines to one of the
PBXs.

Types of Point-to-Point

Connection
There are different types of connec-
tion available for an ISDN point-to-
point connection between two PBXs,
depending on the distance between
them.
Direct Connection
This type of point-to-point connec-
tion joins the two systems directly to
each other using a crossover
twisted-pair cable. An S
can be used for distances up to 1,000
metres. Normally one PBX is the pro-
tocol master for all three layers, and
the other PBX is the protocol slave
for all three layers.
PBX 1
L1 master
L2 master
L3 master
Direct connection
Use the RJ45 jacks on one of the
■
external S ports for an S
0
nection between two
OpenCom 130s. You can use the
corresponding pressure termi-
nals for S ports on interface
0
cards.
PBX Networking
connection
0
PBX 2
L1 slave
L2 slave
L3 slave
con-
0