Call router configuration task list
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SmartWare Software Configuration Guide
40 • Call router configuration
interfaces IF-BRI0 up to IF-BRI3. All four ISDN interfaces lead to the same provider. Since the call router
does not know the load on the BRIs, it has to be able to try BRI0 and, if BRI0 already serves two calls, use
BRI1, and so on.
Figure 66. Hunt group service
The hunt group service accepts a call routed to it by a routing table or directly from an interface and creates
another call that is offered to one of the configured destination interfaces.
The interface tried first (IF-BRI0) may drop the call telling the service that the interface has no resources to
handle the call (e.g. no circuit channel available). Note that only the call between the hunt group and the des-
tination interface is dropped, while the original call between the SIP interface and the hunt group service
remains connected.
The hunt group then decides to try the next destination (IF-BRI1), which in turn also drops the call due to
unavailable resources. In our example the hunt group then tries the third and eventually the fourth destination.
When an interface accepts a call, the interface hunting is complete and the hunt group service merges the orig-
inal with the new call to the interface that accepted the call.
You can influence the algorithm of the hunt group by several configuration commands. You can specify
whether the hunt group shall always start with the same destination interface or whether it shall immediately
try the next one in a round-robin fashion. This is called cyclic operation mode.
You can specify a timeout after which the next destination interface is tried when there is no answer at all from
the destination interface.
You can specify drop causes that trigger hunting for the next destination. All other causes (e.g. user busy) will
drop the original call.
Context
interface sip IF-SIP
interface isdn IF-BRI0
Call Router
a
b
c
first routing table
a A
b B
mapping table
i
j
k
routing table
hunt group
service
route
execute
route
route
interface isdn IF-BRI1
interface isdn IF-BRI2
interface isdn IF-BRI3
route
route
route
