Replay encryption question

[poltergeisty]

Could one replay encrypted audio into a decoding program where they provide the key and hear the decrypted transmission?

If so, does the audio quality have to be wav or can it be MP3?

 

[boatbod]

Could one replay encrypted audio into a decoding program where they provide the key and hear the decrypted transmission?

If so, does the audio quality have to be wav or can it be MP3?

In order to decrypty anything you need to reverse the encryption process. In the case of encrypted P25, DMR, or other digital transmission methods, you need the transmitted data in it's digital form. It is quite possible to receive an encrypted signal, extract and save the binary AMBE/IMBE codewords, then later run them through a decryption algorithm with the proper key, but simply recording a .WAV file of the garbled audio isn't going to get you something you can post-process.

 

[jonwienke]

You need the unaltered encrypted data, the key, and the algorithm. The erroneously decompressed audio you get after feeding the encrypted data through the decompression codec isn't decryptable, even in uncompressed wav format, and you have the key.

 

[poltergeisty]

Kinda figured that.