Features
467
System functions and features as of R3.0
syd-0367/1.3 – R3.0 – 03.2013
9. 6. 17
Callback if user busy / free
This feature is used to obtain an automatic callback if a user is busy or if a call to a
user who is signalled as free goes unanswered.
9. 6. 17. 1
Callback if user busy
User A has the possibility of activating a callback to busy user B (callback request).
As soon as the busy user B becomes free, user A will be called back within 10 s. As
soon as A picks up the phone, the system automatically calls user B, who is now
free.
Fig. 221
Callback if user busy
Detailed Description
Tab. 271 Callback if user busy
The callback is triggered only to user A, who set the callback, regardless of whether
a CFU or CFNR to a user C has been activated at A.
Amount of time a callback if busy remains valid:
• B is internal: 45 min
Interface
Operating sequence / signalling on the ter-
minal
Scope
A
Once the function has been executed, A
obtains the acknowledgement tone.
Restriction:
User A can only initiate one callback at a
time.
B
Possible interfaces:
internal, external
1)
, PISN
2)
Restriction:
Only one callback at a time can be loaded
onto an external user or a PISN user.
1)
Callback to the busy external user is possible only if the public network supports the service "Completion of
Calls to Busy Subscriber" (CCBS) end-to-end.
2)
If the PISN user is reached via the public network, the conditions of the public network for callback when
busy will apply.
