Samsung GH68-06484A Owner's Manual page 134

Caller ID
You can prevent your phone number from being
displayed on the phone of the person being called.
Note: Some networks do not allow the user to change
this setting.
The following options are available:
Default: the default setting provided by the
network is used.
Hide number: your number does not display on
the other person's phone.
Send number: your number is sent each time you
make a call.
Closed user group (CUG)
This network service allows incoming and outgoing
calls to be restricted to a selected user group. You
can create up to 10 user groups.
For details about how to create and use a closed
user group, contact your service provider.
Example: A company lends SIM cards to its
employees and wants to restrict outgoing
calls to members of the same team.
Activating a closed user group
If you select the Closed user group menu, you
can enter the CUG function. You can access the
following options after pressing the Select soft key
or the Centre key:
(Menu 7.5.5)
(Menu 7.5.6)
Settings
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