Aastra OpenCom 100 series, Руководство по монтажу и пусконаладке

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PBX Networking
167
• PBX 1 first searches for a free channel in the “C” bundle.
• If all the lines in bundle “C” are busy, the system tries to set up a connection via
bundle “E”. PBX 3 switches the connection through, provided it is appropriately
configured (refer to Numbering starting on page 167).
• If it was not possible to set up an indirect connection via PBX 3, the system tries
again via bundle “A”. The “prefix” necessary for this can be configured with the
route.
• The user does not get a busy signal until the attempt to set up an indirect con-
nection via the network operator has also failed.
Note
If an internal connection is switched via a network operator, the call is signalled using
the external number of the calling PBX.
For each route you can define a randomly selectable code digit for seizing the route.
You can also configure whether a user is authorised to seize a particular route,
whether LCR is to be used for one of the bundle and the criteria (business or private
call, booking numbers) for evaluating call data.
Numbering
A user can seize a particular route by pre-dialling a specific code digit. With this “open
numbering”, a user must always dial this code digit and then the telephone number in
order to reach a party in another PBX.
If none of the telephone numbers in your PBX network occur twice, you can also con-
figure “closed numbering”, allowing the same telephone number to be used for
reaching each user within the PBX network.
With closed numbering, the OpenCom 100 determines which route to seize from the
telephone number dialled. The information needed for routing a call can be con-
figured in a numbering table containing up to 100 entries. You use this table to assign
telephone numbers and/or ranges of telephone numbers to a particular route.
A default entry in the numbering table makes it possible to seize a “default route” for
all remaining unassigned numbers. In particular, this simplifies configuration of the
OpenCom 100 as a subsidiary system: the only entry you assign to the
default entry is
the route to the host system