Types Of Point-To-Point Connections; Direct Connection - Aastra OpenCom 510 User Manual

PBX Networking
If more than one port with the setting L1 Type = "Slave" is configured on an
OpenCom 510 and the setting L1 sync possible has been activated, then one of
the ports is automatically defined as the L1 clock source. The OpenCom 510 will
automatically switch the clock source to another port configured as an L1 clock
source (if a line fails, for example).
LED 3 (top right) of an interface card will light up if one of the interfaces on the
card has been selected as a clock source. If an S
1 is installed, it will be selected as the preferred clock source.
Please note:
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 temporarily.
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.
13.2

Types of Point-to-Point Connections

There are different types of connection available for an point-to-point connection
between two PBXs, depending on the distance between them.

13.2.1 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
tances up to 1,000 metres, while an S
Normally one PBX is the protocol 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
Reciprocal or circular application of the L1 clock is not allo-
wed.
2M
PBX 2
L1 slave
L2 slave
L3 slave
Types of Point-to-Point Connections
interface of the type MT+S2M1-
2M
connection can be used for dis-
0
connection can span up to 250 meters.
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