E.F. Johnson Company Viking VM600, Руководство по эксплуатации

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Draft 02 - Sep 1 2015
Viking Mobile Radio Operating Manual 7-5
Secure Communication (Encryption)
7.2.3 Maintaining Keys in Memory
The radio may need to be connected to a constant power source to preserve the encryption
keys in memory. The programming of the Infinite Key Retention parameter determines if
keys are permanently stored in memory or erased soon after power is removed.
When Infinite Key Retention is enabled, keys are stored in memory and are not lost when
power is removed.
With Viking Series mobile models, the keys are maintained for approximately 24 hours
with this feature disabled. However, a tamper switch causes immediate key erasure when
the radio cover over the logic board is removed.
7.2.4 Encryption Key Select
When multiple encryption keys are programmed (see preceding information), the Key
Select option switch can be programmed to allow selection of another key for the current
channel. This feature changes the PID (hardware location) of the key on the channel for
Conventional Digital and P25 Trunking Talkgroups, and the change is permanent (cycling
power or selecting a different channel does not reselect the original key). Therefore, to
switch back to the original key, it must be manually reselected. Proceed as follows to
select a key:
Note
This feature is available on conventional channels or on P25 Trunking channels.
1
Press the Key Select option switch and HW KEY (or SW KEY, if optioned/
programmed for software keys) will be displayed.
2
Rotate the Select switch to display the desired key and then press the Select switch to
select it. Press the Key Select option switch again to return the display to normal
operation.
7.2.5 Encryption Key Erase
An Erase Keys option switch can be programmed that allows the user to permanently
erase all stored keys. If OTAR TEK and KEK keys are stored, all keys of both types are
erased. This function can be used to ensure that unauthorized encrypted calls can no
longer be placed or received by a radio.