Logging encrypted talkgroups?

hruskacha

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Before I begin to ask this question, let me clarify that I do NOT want to decrypt the encrypted talkgroups or anything like that. I simply want to see when the group is active, for time logging.

I use SDRTrunk and Trunking Recorder to listen to MPSCS's Digital P25 Phase 1 Trunking System.

SDRTrunk uses JMBE to decode (NOT decrypt) the voice channels that are scanned by my system, however, JMBE does not process or create a file for any encrypted traffic. Which is fine, I don't need to hear it, but I still want to see when they are in use? SDRTrunk does show on screen when encrypted talkgroups are talking, but it doesnt log any information regarding the call because it would be stored in the non existent audio file for that call.

Unitrunker (used with DSD+) functions a little different and actually produces an audio file for encrypted traffic (scrambled audio only though since its not decrypted) and has the metadata with it.

What can I do to log the encrypted traffic without using Unitrunker? I cannot run both simultaneously because SDRTrunk allocates ALL SDRs attached to the system.
 

maus92

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I have used Unitrunker 2 and SDRTrunk simultaneously, so it can be done. Start a radio in UT first, then start SDRTrunk.
 

Forts

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I use DSD+ extensively on MPSCS and it's easy to log all groups, encrypted ones included, with it.
 

polkaroo

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Maybe a feature request then to the DSDPlus authors for "logging" option for encrypted talkgroups where it can still tune to an encrypted talkgroup, find the algorithm and KID and then move away or back to the CC since the chatter itself is un-listenable anyway.

While we can't listen in, you can at least somewhat ascertain groups of users.
 

n3obl

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How does the algo and KID help with that?
Intelligence gathering. maybe they use a select channel with part time encryption and helps identify users on another.
 

TDR-94

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With L3HARRIS radios that data can be obscured, so that the info is meaningless.
 

jake_Braker

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Running either DSD+ or UT by itself creates the log you are looking for.
Is there a better way I can tell if a TG is encrypted other than the channel activity log? I normally leave my computer running DSD while I'm away from home and come back to a few unknown talkgroups with no indication of encryption.
 

N1GAW

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Is there a better way I can tell if a TG is encrypted other than the channel activity log? I normally leave my computer running DSD while I'm away from home and come back to a few unknown talkgroups with no indication of encryption.
Have u tried looking at the DSDPLUS.event log, it tells you if a call was encryption. An example is below

2021/02/12 21:48:55 Freq=856.662500 NAC=591 Enc Group call; TG=46679 RID=64400 Ch=859.4875 Alg=ADP 3s
2021/02/12 21:49:00 Freq=856.662500 NAC=591 Enc Group call; TG=46679 RID=1831880 Ch=859.4875 Pri0 Alg=ADP 2s
2021/02/12 21:49:03 Freq=859.487500 NAC=591 Enc Group call; TG=46679 RID=64400 Ch=859.4875 Alg=ADP 13s
 
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