Algorithm id (algid), Key id (kid) – Codan Radio P25 Training Guide User Manual

Page 37

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P25 RADIO SYSTEMS | TRAINING GUIDE

Chapter 3: P25 Technical Information Page 29

Algorithm ID (ALGID)

The Header Code Word and Encryption Synchronization (LDU2) contain the 8 bit ALGID fi eld. The
ALGID identifi es the encryption algorithm used in the P25 system. The ALGID is entered through a Key
Management Facility or Key Loader when entering encryption keys.

The ALGID’s that have been defi ned for Type 1 algorithms are:

$00 ACCORDION

1.3

$01

BATON (Auto Even)

$02 FIREFLY

Type

1

$03 MAYFLY

Type

1

$04 SAVILLE

$41

BATON (Auto Odd)

$80

Unencrypted message (no encryption algorithm)

$81

DES-OFB encryption algorithm

$82

2-key triple DES encryption algorithm

$83

3-key triple DES encryption algorithm

$84

AES encryption algorithm

(See Chapter 4; Figure 4-4 and Figure 4-9)

Key ID (KID)

The Header Code Word and Encryption Synchronization (LDU2) contain the 16 bit KID fi eld. The KID
identifi es the specifi c encryption key for use when multiple encryption keys have been loaded into the
encryption modules. The KID is also used for single encryption key systems. The typical default KID
for clear or secure systems is $0000. The KID is entered through a Key Management Facility or Key
Loader when entering encryption keys.

(See Chapter 4; Figure 4-4 and Figure 4-9)

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