Zultys ZIP4x4, Руководство пользователя

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7. Special Functions
57
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If your phone is configured for always on or never on , the phone system must support
encryption in the former case or must be able to establish communication without encryption
in the latter case. If the phone system cannot communicate with your phone, your phone
rejects the call and your conversation is not placed on hold. Depending on the phone system
your call may then be dropped or the phone system may reconnect you to the other person.
If you put a call on hold successfully, the phone turns off the LED on the Encrypt button. If the
phone system rejects the call and does not return the call to your phone, the call will be dropped
and the ZIP4x4 will turn off the LED on the respective call appearance button.
As another example, consider the case when you transfer a call or you have set call forwarding
rules so that calls are automatically routed to another destination. The policies of the devices used
by the original caller and the final called party must match or the call may be dropped.
7.2.4 Conference Calls
7.2.4.1 General
All calls that comprise a conference call must be encrypted or not encrypted. You cannot mix calls
on a conference call that are encrypted or not encrypted because this makes the entire conference
subject to eavesdropping and is therefore not secure.
After you have set up the call with the first person, all subsequent calls added to the conference
must be encrypted or not encrypted depending on whether the first call has encryption engaged
or not. You can join other parties to the conference in the same way that you can you can join
parties for a conference that is not encrypted and as described in section 8.8.5 on page 101.
7.2.4.2 Adding Other Parties to an Encrypted Conference Call
If you have established an encrypted call, you cannot add other calls to the conference that are
not encrypted:
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If you place the conference on hold and make a call to another person, pressing the conference
button will have no effect and you cannot join the person to the call if that new call is not
encrypted.
•
If you press the Conf key to select a new call appearance and then you call another party that
will not support the request for encryption, your ZIP4x4 drops the call if it was not rejected by
the other party and shows:
The phone shows the call appearance number and the name, number, or address of the
person you were trying to call. The phone holds this display for two seconds then reverts to
the previous display.
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If you have one or more incoming calls and you press the Conf key to join those calls to the
conference, your ZIP4x4 joins only those parties to the call that are encrypted. The phone
continues to alert you that you for the call or calls that could not join the conference. You need
to place the conference on hold to answer the other call or calls.
3. Encrypt Rejected
Technical.Support