EF JOHNSON 5100 ES II, Operating Manual

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December 2006 5100 ES Model II/III Portable Radio Operating Manual 10-3
Secure Communication (Encryption)
If an attempt is made to transmit a secure message without loading the corresponding key,
“Keyfail” is displayed. The message must then be transmitted in the clear mode (this is
possible only if the channel is strapped to “switchable”) or the key must be loaded.
10.2.1 Key and Algorithm IDs
Each encryption key is programmed with a Key ID (also called Logical ID). This ID plus
the algorithm ID (ALGID) is transmitted in the message on digital channels. The radio
receiving the message must have a key with the same IDs in order to decrypt it.
10.2.2 PID/SLN Key Management Modes
Note
The term “SLN” from the Project 25 specification is equivalent to “CKR” (Common Key
Reference) also used to define this parameter.
The channels, talk groups, and other calls that use encryption are linked to a specific
Physical ID (PID) when the radio is programmed using the PC Configure programming
software. For example, Zone 1, channel 1 could be programmed to select the key in PID 1
and Zone 1, channel 2 could select the key in PID 3. The PID ranges are 0-15 when the
PID mode is selected, and 1-16 when the SLN mode is selected (see Figure 10.1).
Figure 10.1 Key Selection Example
PID or SLN key management modes can be programmed on the Global programming
screen. More information on these modes follows.
PID Mode - The PID mode can be used only when keys are loaded using the Motorola
KVL 3000 keyloader operating in ASN mode. When this mode is selected, keys are
loaded directly into a PID of 0-15 that corresponds to the PID programmed for each
channel (if applicable). The Keys Table in PC Configure is not programmed with this
mode.
SLN Mode - The SLN mode must be selected when either OTAR (Over-The-Air-
Rekeying) or the EFJohnson System Management Assistant (PDA keyloader) or the
Motorola KVL 3000 keyloader operating in Astro 25 mode is used. It can also be used
if OTAR is not used. With this mode, keys are loaded into a SLN (Storage Location
Algorithm ID
Keyset Name (Opt)
SLN 23
SLN 25
Algorithm ID
Keyset Name (Opt)
Key #21: Key ID 54
SLN 24
SLN 22
SLN 21
Keys Table
3
5
4
2
1
PID
Key #22: Key ID 65
Key #23: Key ID 67
Key #24: Key ID 69
Key #25: Key ID 73
Key #25: Key ID 90
Key #24: Key ID 91
Key #23: Key ID 99
Key #22: Key ID 98
Key #21: Key ID 94
Keyset 1
Keyset 2
Zone 1, Chan 2
Zone 2, Chan 4
Zone 2, Chan 5
Zone 3, Chan 1
Zone 3, Chan 2