TD 92326GB
2009-03-10 / Ver. E
Installation and Operation Manual
VoIP Gateway
148
In this case, make certain that the “Verify CGPN” check box is selected. Note also that
during the execution of a route, the interpretation of calling numbers is always
independent of the type of address (see section
on page 142) with the effect that no address types can be specified here.
21.7 Define Call Number Replacements
It often makes sense to replace dial prefixes generally and independent of individual
routes, for instance to implement abbreviated dialling. Here the abbreviated dialling
number is replaced by the complete number and then routing is performed again for the
now complete number.
This can be achieved by defining a route to the destination “MAP” in the destination
drop-down list. After the number replacement, the call is not connected in the usual way
but a suitable “Map” is searched for in the routing table with the replaced call number.
Please note that in order to avoid endless replacement operations only the routes after the
“MAP” route (text-wise) are searched through. “MAP” routes must thus always be
specified before the routes that define the treatment of the replaced number.
21.8 Configuration of Multiple Routes for a Dial Prefix
Different routes for different call sources for the same dial prefix can be specified, with the
effect that the routing process is dependent on the call source and not only on the called
number.
21.9 Call Forwarding
Several routes for calls from the same call source with the same dial prefix can be defined.
The gateway's routing process always uses the first suitable route. If a connection cannot
be established using this route however, a further attempt can be made using another
route. Various types of call forwarding can be implemented in this way.
• If an attempt is made to switch a call using a route and this call is unable to be set up
due to missing local resources (for example, no exchange line available, see the table
“Local problems” concerning call forwarding
on page 149), a search will immediately
be made for a further route.
If several exchange lines are connected to the gateway, this allows the calls to be
distributed successively around the exchange lines.
• If a route is used to make an attempt to switch a call and the call can be successfully
signalled to the called terminal, and if a value greater than 0 has been entered in the
“Timeout” field for this route, then a search will be made for a further route if the call
is not accepted within the specified number of seconds. This corresponds to the “Call
forwarding no response (CFNR)” function. If you enter a “Timeout” of more than 120
seconds, this timeout will have no effect since the global timeout for setting up the call
will expire first. Since, if timeout is entered, available alternative routes will always be
tried, after a failed call, it has the same effect as the “Call forwarding busy” (CFB)
function.
Select the “Final Map” check box if, after attempting to switch a call using a map entry,
you want to prevent further routes from being tried out.
