Encrypted dmr trx

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vocoder

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Has anyone encountered encrypted dmr conventional on the trx? How does your trx handle it?
Does the trx use any of your encryption alert settings?
Ive seen the trx handle the p25 encryption settings by sounding the telephone busy tone
Was wondering if the same for dmr
Thanks
 

Ubbe

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You got 3 different settings on a TRX to handle encryption audio. Either you could listen to the actual encrypted digital signal or have it replaced by a busy tone or totally muted audio.

/Ubbe
 

RayAir

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It doesn't detect the following as encrypted (DMR):
-Hytera Basic Encrypt (40,128, or 256 bit)
-Mototrbo Basic Privacy

I'm guessing it doesn't detect these because there's no privacy indicator header, but the privacy bit is set. It must not look at that.

The above are detected by DSD as Alg=BP. The Hytera Basic Encrypt isn't as common since there's more Moto systems than Hytera, but the HYT Basic Encrypt sounds exactly like MotoTRBO enhanced or HYT full encrypt (RC4 or AES). You'd need DSD if you really wanted to differentiate the two, but it's not necessary since it can't be monitored anyway.

It also won't detect basic or enhanced privacy from cheap chicom dmr radios like the md-380, but neither does dsd and this is a non issue
 

Ubbe

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Refering to your Lake Placid experiance with DMR basic encryption that you say sounds like voice but with some kind of voice inversation being done to it, I have nothing that sound like that on the systems that uses basic privacy. It sounds pure digital and could be said to sound like pouring water.

It must had been some encryption being done directly to the audio in the radios in a p2p link and that would not set the encryption flag in the DMR protocol, that all scanners and radios need to use to be able to identify an encrypted transmission.

/Ubbe
 

vocoder

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It doesn't detect the following as encrypted (DMR):
-Hytera Basic Encrypt (40,128, or 256 bit)
-Mototrbo Basic Privacy

I'm guessing it doesn't detect these because there's no privacy indicator header, but the privacy bit is set. It must not look at that.

The above are detected by DSD as Alg=BP. The Hytera Basic Encrypt isn't as common since there's more Moto systems than Hytera, but the HYT Basic Encrypt sounds exactly like MotoTRBO enhanced or HYT full encrypt (RC4 or AES). You'd need DSD if you really wanted to differentiate the two, but it's not necessary since it can't be monitored anyway.

It also won't detect basic or enhanced privacy from cheap chicom dmr radios like the md-380, but neither does dsd and this is a non issue

This is what i had been thinking, cuz i have a conventional dmr frequency here that doesnt decode. I threw it in analog mode and you can hear the raw dmr and the resting dmr trailer. But the neighbors trx never sounded the busy signal like it does on federal encrypted p25.
 

Melv7956

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You got 3 different settings on a TRX to handle encryption audio. Either you could listen to the actual encrypted digital signal or have it replaced by a busy tone or totally muted audio.

/Ubbe



I don’t think this works with dmr but would love to be proved wrong.


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racingfan360

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I don’t think this works with dmr but would love to be proved wrong.
Sent from my iPhone using Tapatalk

Subject to Rayair's caveats, some of I which I can personally verify and others I haven't (but they do make sense), I can confirm this is how a TRX1 handles Enhanced Privacy DMR as well as standard NXDN encryption.
 

PrivatelyJeff

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You got 3 different settings on a TRX to handle encryption audio. Either you could listen to the actual encrypted digital signal or have it replaced by a busy tone or totally muted audio.

/Ubbe

I wish it would just skip over it.
 

mejnetguru

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I wish it would just skip over it.

Me too. It gets particularly annoying when a center patches together two+ TGs, one or more of which is encrypted. The scanner stops even though I monitoring the non-encrypted TG(s). In the meantime, missing traffic elsewhere while it's stopped unnecessarily. Wish-list for Whistler: Add option to auto-proceed/skipover encrypted traffic.
 

PrivatelyJeff

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Simple - just lock it out.

Me too. It gets particularly annoying when a center patches together two+ TGs, one or more of which is encrypted. The scanner stops even though I monitoring the non-encrypted TG(s). In the meantime, missing traffic elsewhere while it's stopped unnecessarily. Wish-list for Whistler: Add option to auto-proceed/skipover encrypted traffic.

Sorry, I meant for when a channel sometimes uses it. My local navy base is usually in the clear, but sometimes uses encryption. Same with a couple of local LE agencies.
 
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