DMR encoded audio, is it possible to hear this audio?

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Motursa

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Could someone explain to me if this audio system can be decoded with dsd?


I have tried the fast lane version and I always get the same audio which I show below


* This is a sample of the sample audio "Click download"


this audio was obtained with a free version and virtual audio output using a uniden radio with discriminating trap, at the moment I am doing a simple search without any trunking system



84863
 

wx5uif

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The lines with Enc are encrypted and you cannot hear them. There are two (without the Enc) though that should of had audio though.


Edit: Just listened to the audio file. Yeah that is encrypted DMR.
 

boatbod

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DMR Basic Privacy is just an XOR so it is easily reversed as there are only 2^8 choices of key. Enhanced Privacy not so much.
 

ScubaJungle

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Im not encouraging anything thats not allowed, but wasn't there a receiver (European I believe - possibly Russian), that was on the market that handled BP encryption? I believe it was called "AR-something"?
 

Motursa

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DMR Basic Privacy is just an XOR so it is easily reversed as there are only 2^8 choices of key. Enhanced Privacy not so much.

I find your comment interesting. Can you explain a little more about what DMR refers to: basic privacy is XOR?
 

hrh17

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Yeah if they are running BP you could just get a mototrbo radio and try the guessing the right key. Only 255 combinations lol
 

boatbod

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basic privacy is XOR?
Correct.
There are 255 key id value that correspond to a table of predefined 16bit XOR masks which get applied to specific parts of the xMBE codewords. I'm not going to explain any more details... it's all out there on the 'net for your own research.
 

TheButcher

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There is a bug in DSD+ that means EP shows as BP sometimes. Same with AES. I posted this but fell upon deaf ears...

Monitor for a while and see if it stays on BP. Then yea... As above!


I see that you are NOT running FL version. With FL, one can set it up for trunk tracking. Site you shown is "Connect plus"...
 

slicerwizard

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There is a bug in DSD+ that means EP shows as BP sometimes. Same with AES. I posted this but fell upon deaf ears...
It's probably not a bug. If your decode rate is poor and DSD+ doesn't see the PI header, the only information it has to go on is the privacy bit in the voice header, and that would normally mean BP.
 
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TheButcher

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Signal strength and gain settings (decode rate) are fine. I doubt it would be interferance from adjacent channel, or local noise etc...


"It's probably not a bug. If your decode rate is poor and DSD+ doesn't see the PI header, the only information it has to go on is the privacy bit in the voice header, and that would normally mean BP. "

I considered that. Needs some fuzzy logic me thinks!. If say, on a certain TG, EP is detected 95% of the time, why show BP 5% of the time incorrectly / erroneously. Extra flag in the .bin file / groups or radio files, may be would solve this? I have not had ENC ALG show erroneously on CLEAR signal.

Might be a bug in the ENC voice mute code? Also, if TS1 is in use (CLEAR), if TS2 is ENC, and both TG's are sharing the same frequency, both the TG you are monitoring AND the ENC one shows up in the VC window, which IS a bug (IMHO)... Hopefully I get heard this time! Or I may of explained things better...
:)

Does same thing (bug) with AES256 too...




XOR = Exclusive OR. Here is the truth chart... Essentially, it is a scrambler.

.85086
 
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slicerwizard

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Needs some fuzzy logic me thinks!. If say, on a certain TG, EP is detected 95% of the time, why show BP 5% of the time incorrectly / erroneously.
So if most users on a group are using EP most of the time, but there is some BP use for whatever reason - techs doing testing / an SDR# feed that's actually scanning between EP and BP channels / whatever - show what you want to see, rather than what's actually happening / being decoded? That's not what I would want.
 

TheButcher

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You are using one example. My example is completely different whereby there are two TGs on a large system and only 2 of them are using EP. Nobody is using BP. So yea, I would rather not see false negatives and bleed over of TG's shown in the VC window...
 
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