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f4exb / dsdcc

Digital Speech Decoder (DSD) rewritten as a C++ library
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Basic Privacy (Question) #30

Closed moneriomaa closed 4 years ago

moneriomaa commented 4 years ago

Hi thanks for your job i read etsi dmr document (ETSI TS 102 361-1 V2.4.1 (2016-02)) in page 21 Voice frame shows that contains 2108( =372 bit of voice)+48(sync or embedded) before it delivered to ambe+2 voice decoder in basic privacy as i read 255 of 16 bit keys is conceivable, my question is that Where does 16 bit key apply? (it applies on 3*72 bits? and 72 bits converts to 49 bits, Key must be XOR with 72 bits or 49 bits? and how i can create 49 or 72 bits from 16bit key for xor to data is there any suggestion that where can i find my answer?

Update: Solved (49 bits of key xored with 49 bits input of vocoder) thanks

f4exb commented 4 years ago

Please have a look on the latest code (v1.8.7) that implements basic privacy. Maybe this answers your questions.

f4exb commented 4 years ago

Solved (49 bits of key xored with 49 bits input of vocoder)

That's what it is supposed to be indeed but does not work here. Anyway question is answered