Auerswald COMpact 4000 Operation Manual page 436

Functions
Call Channel Reservation
Switching Call Channel Reservation On/Off
4. In the Number list field, select how many B channels of the external connection
should be reserved. These B channels are never available to the other subscribers or
groups.
Note:
If a channel should be reserved for one subscriber this subscriber has to be
assigned alone to a group.
A B channel reserved for a group is only available for the members of the
group who are logged in the group outgoing.
436
COMpact 4000 - Firmware V6.6A - Installation, Operation and Configuration V03 03/2016