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Section 11

This radio may be equipped to provide secure communication on some or all channels. 
This feature encrypts the voice so that it can be understood only by someone using a radio 
equipped with a similar encryption device and encryption codes.

When a secure call is received or transmitted, 

 is indicated in the display (see 

Section 11.2.6). If equipped with the Clear/Secure option switch and the current channel is 
programmed to allow switch selection, secure communication can be manually enabled 
and disabled by that switch. Otherwise, channels are strapped to Clear or Coded operation 
(see Section 11.3). Secure communication can be programmed on a per channel or per talk 
group basis to operate in various ways. More information follows.

SecureNet encryption digitizes the voice and then encrypts it using the DES or DVP 
algorithm. It uses a 64-bit encryption key. The SecureNet protocols include the following 
algorithms:

• DVP (Digital Voice Privacy) is an earlier encryption method that is self synchronizing 

using cipher feedback. It was originally designed to be used by anyone needing 
protection from unauthorized eavesdropping.

• DES (Data Encryption Standard) provides a higher level of security, and also uses 

cipher feedback. It was originally designed to be used only by the Federal government.

• DVP-XL - A disadvantage of the DVP and DES encryption types is reduced 

communication range when compared to clear voice. The DVP-XL methods was 
designed to provide better range but at the cost of lower voice quality. They use a 
different type of feedback called counter addressing.