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

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Draft 02 - Sep 1 2015
Viking Mobile Radio Operating Manual 7-7
Secure Communication (Encryption)
If the Clear/Secure switch is not programmed, the radio is always in the last known state
(usually Clear) and there is no way to change it. For example, if the last known state is
Clear and this parameter is not selected, it is never possible to transmit a Secure message
on a channel strapped Secure because all that happens is transmitting is disabled, an error
tone sounds, and “SEC ONLY” (Standard Control Head) or “Secure Only” (Lightning
Control Head) is displayed.
7.4 Security Settings Override
The default security settings that determine how encryption keys are used for talkgroups
and channels can be changed for different operating modes.
7.4.1 P25 Conventional and Trunking Talkgroup Security
Override
Conventional digital (P25), Smartnet/Smartzone and P25 Trunking encryption strapping is
programmed on a “per talkgroup” basis. However conventional digital and P25 trunking
talkgroup encryption strapping can be overridden on a “per channel” basis.Therefore, if
desired on Conventional Digital and P25 Trunking channels, encryption can be
programmed differently for each channel.
7.4.2 Secure Call Behavior
7.4.2.1 Failsoft, Group Regroup or Dynamic Regroup Call
If the radio is in failsoft or is dynamically regrouped, the radio will behave as it always
has. That is, the radio will use any key to decrypt a received call and will transmit using
switched strapping and the key PID specified as originally programmed.
If the radio is group regrouped, most functionality is retained. The radio will continue to
use the key PID specified (as programmed) or use any key to decrypt a received call. The
radio will use the keys based on programming values for Failsoft, Patch, Unit Call,
Interconnect, and Dynamic TG: when the radio is in these modes, the radio will not use the
strapping of the current channel. This means that if the channel has the override feature
enabled, the strapping specified in this section will be used for the channel. If the override
feature is not enabled, then the strapping of the currently selected talkgroup will be used.