Technical Details
PBX Networking
143
Example of closed numbering tables
The automatic switching of call requests (i.e. routing) by means of bundle
overflow or default numbering can lead to “circular switching”.
To avoid this, a “transit” counter is incremented whenever a connection is
switched through on Q.SIG lines. When the configured maximum value is
reached, further switching stops.
Technical Details
A different PBX number must be set for each Forum 523/524 in a PBX
network. This setting can be found in the Web console, in the menu
Tele-
phony: Settings
under the heading
QSIG linking
. You can also set the
maximum value for the transit counter there. This value depends on the
topology of the PBX network and should allow the system to have the
maximum number of further connections possible.
You can display the connection status of the lines at any time in the Configu-
rator menu
System Info: Telephony: Trunks
. You should check this in
particular after making changes to a configuration to see whether all the lines
used for system networking are operable.
Not all options of some Q.SIG are supported by the Forum 523/524, for
example callback on busy within the Q.SIG network or route optimising. The
call categories defined in Q.SIG (e.g. Emergency Call, Operator, Normal) and
the Q.SIG name transmission feature (“user names”) are fully supported.
The code digits to be used for seizing a route with open numbering are not
transmitted to the destination PBX and thus cannot be evaluated by it. To
reseize a route (for example for a callback), you must set the appropriate digit
prefixes in the bundle configuration for the routes to be reseized.
PBX
200-
299
PBX
500-
599
PBX
300-
399
PBX
100-
199
PBX
400-
499
D: a
4: b
D: c
3: e
5: h
D: d
3: i
D: g
5: k
D: f
a
b
c
d
e
f
g
h
i
k
D:Default
D:
Route
