Encrypted subcode?

[BinaryMode]

Was or is there such a thing? Like an encrypted DCS code or maybe even a type of rolling code voice inversion for CTCSS. The theory I have is to just help keep people off a repeater or your two-way radio. Keyword here is "help." I highly doubt it would be full proof. You'd input like a five character key and now you have some 5 million different sub codes...

 

[a417]

Was or is there such a thing? Like an encrypted DCS code or maybe even a type of rolling code voice inversion for CTCSS. The theory I have is to just help keep people off a repeater or your two-way radio. Keyword here is "help." I highly doubt it would be full proof. You'd input like a five character key and now you have some 5 million different sub codes...

Lol, no.

"Privacy tones" are marketing wank from 4ish decades ago, they are not encryption.

CTCSS/DCS are selective muting criteria.

Encryption is encryption.

 

[BinaryMode]

You need to read what I said again. I was not inferring that a subcode was full on voice encryption. I stated encrypted subcodes... So that it would make it harder for a person to tie up a repeater or interfere with a two-way radio convo...

Note I also said the following:

The theory I have is to just help keep people off a repeater or your two-way radio. Keyword here is "help." I highly doubt it would be full proof.

 

[a417]

You need to read what I said again. I was not inferring that a subcode was full on voice encryption. I stated encrypted subcodes... So that it would make it harder for a person to tie up a repeater or interfere with a two-way radio convo...

Note I also said the following:

I love your word salad, its very easy to digest.

You want pretend, subtly harder encryption that you're not calling encryption.

 

[Pape]

To mitigate replay attack you will need a good way to insert a salt in the encryption algorithms. This is where the supporting infrastructure come in and the complexity kick in.

 

[buddrousa]

He also wants what he is against in other post.
People not interfering with his repeater and hearing him.

 

[mmckenna]

You need to read what I said again. I was not inferring that a subcode was full on voice encryption. I stated encrypted subcodes... So that it would make it harder for a person to tie up a repeater or interfere with a two-way radio convo...

That's not going to work.
Someone that wants to interfere doesn't need to have the correct PL/DPL codes to do it. They just need to get enough RF into the receiver to screw things up.

If you are trying to keep someone that does not have permission from utilizing a conventional repeater without resorting to encryption, that's pretty difficult.

No, there is no encrypted DPL or PL method that is in use. If someone wants to secure a repeater, they use full on encryption.

There are some in the ham/GMRS world that have utilized LTR single channel systems to block users that do not have the correct information.
Kenwood NXDN single channel trunked will let you lock down the system to only allow radios that have their ESN and radio ID in the system.
Some have used MDC1200 repeater control, which while not secure, keeps the CCR's out of the system.

 

[mikegilbert]

I like the single channel LTR idea!

You could find a Zetron 38A repeater controller and do the following:

Turn on the anti-kerchunking filter so they can't hunt for the new PL
Set a different PL/DPL tone for the input, but keep the existing output PL/DPL
Enable "reserved user" on the panel with your former PL/DPL, which will mute their audio and send beeps over the air.

If they monitor your input, they'll figure out the new PL/DPL code, but it might help keep them off.

https://www.repeater-builder.com/zetron/pdfs/zetron-38a-manual-with-schematics.pdf

 

[SuitSat]

That's not going to work.
Someone that wants to interfere doesn't need to have the correct PL/DPL codes to do it. They just need to get enough RF into the receiver to screw things up.

THIS !

If someone wants to secure a repeater, they use full on encryption.

THIS too !
But you could also use authentication without needing secure voice (e.g Motorola RAS, Hytera OTA encrypt, or various trunking flavors as you describe below Of course, RAS and similar will not work for OP if he is in a "full analog" context...)

BUT (there's always a but...)
As surprising as it may seem... this thing

encrypted DCS code

seems to exist...

At least if you can cope with CCR !
The Retevis (RT27 ?) boasts the so-called "DCS encryption"...

I guess it's a marketing gimmick with either a non standard way of doing DCS (could be simple non "valid/approved" DCS sequences, a modified bitrate or modified FEC...) or just a fixed XOR with standard DCS codes [with others RT27 having the "keystream" (yeah, that's a big word) built-in], a sort of /\/\ Basic Privacy but for DCS maybe ?

It's just me guessing of course (I don't give a *** about CCR), but the function seems to be legit according to others tinkerers who tried to intercept the DCS with scanners & SDR plugins...


Again, this doesn't change the story for OP, because no repeaters (I know of) implements this functionnality, but I allow myself to write this post just for technical accuracy sake, and for the pleasure of having a debate

Bye

 

[buddrousa]

@SuitSat And if you read the OP POST 1 it states ANALOG CONVENTIONAL REPEATER.

 

[SuitSat]

@SuitSat And if you read the OP POST 1 it states ANALOG CONVENTIONAL REPEATER.

You Don't Say ....

Was or is there such a thing? Like an encrypted DCS code or maybe even a type of rolling code voice inversion for CTCSS. The theory I have is to just help keep people off a repeater or your two-way radio. Keyword here is "help." I highly doubt it would be full proof. You'd input like a five character key and now you have some 5 million different sub codes...

Yeah, the OP CLEARLY stated ANALOG CONVENTIONAL before REPEATER in his post.
I know, I'm not dumb, the mere mention of CTCSS is enough to grasp that (maybe not for you)...

RAS and similar will not work for OP if he is in a "full analog" context...)

[...]

Again, this doesn't change the story for OP, because no repeaters (I know of) implements this functionnality, but I allow myself to write this post just for technical accuracy sake, and for the pleasure of having a debate

Before lecturing others, maybe you should learn to grasp the implicit (and not so implicit) subtleties of a message...
(I'll stop there before KevinC has to do his job)

 

[kayn1n32008]

Was or is there such a thing? Like an encrypted DCS code or maybe even a type of rolling code voice inversion for CTCSS. The theory I have is to just help keep people off a repeater or your two-way radio. Keyword here is "help." I highly doubt it would be full proof. You'd input like a five character key and now you have some 5 million different sub codes...

There is not anything like what you are asking about.

Easiest way, is a Motorla DMR repeater and Motorola subscribers and utilize RAS. that will prevent unauthorized radios from accessing the system, AES256 will keep the nosey scanners out.

 

[BinaryMode]

*Sigh* Again, I'm not talking about voice encryption.

I'm talking about encrypting a subcode so that another user will have a hard time using that encrypted subcode to get on the system or two-way radio Comms.

This is more or less about access control, NOT voice encryption. I never even made mention of voice encryption.

The idea here is not wanting to keep scanners out, just unauthorized transmitters.

I think some users already understand where I'm coming from.

 

[BinaryMode]

He also wants what he is against in other post.
People not interfering with his repeater and hearing him.

The hell?!

 

[mmckenna]

*Sigh* Again, I'm not talking about voice encryption.

We know that.

You asked if there was a feature that would encrypt the PL/DPL tones to control repeater access. Answer is: No.
Reason there isn't is because there are other ways to accomplish this. Easiest one is full encryption, and that is why others have mentioned it as a solution.

If you don't want full encryption, then you'd use one of the other solutions mentioned above: MDC, which really isn't secure, but more obscure, or an LTR controller.

 

[dickie757]

How about having to use a radio that will allow custom PL tones, such as 102? It will kind of do what op wants. A scanner will pick it up, but unless the radio will tx it, no access granted

 

[freddaniel]

I recall many years ago, if you wanted to keep others from accessing your repeater you would use dual-tone PL or a 5-tone burst plus a single PL. Then came DPL and most people used that. There are thousands of combinations that would work.

 

[nd5y]

How about having to use a radio that will allow custom PL tones, such as 102? It will kind of do what op wants. A scanner will pick it up, but unless the radio will tx it, no access granted

If the custom tone you pick is too close to a standard tone you might have problems depending on the CTCSS frequency tolerance of the equipment used and the tones used by others on your frequency.

If you are trying to limit access using non-standard CTCSS tone you are wasting your time because Baofengs allow you to set the CTCSS to anything between 60.0-259.9 Hz in 0.1 Hz steps.

 

[mmckenna]

How about having to use a radio that will allow custom PL tones, such as 102? It will kind of do what op wants. A scanner will pick it up, but unless the radio will tx it, no access granted

Years and years ago I had access to a high level GMRS repeater. The owner gave me my own PL tone. I was fortunate that my radio would support it. 254.1Hz. Not one of the standard EIA/TIA tones. I never heard anyone else.
Many radios will do it, but it'll keep some of the lower tier junk out.
I seem to recall having an Icom that would do custom PL tones, but it wasn't always foolproof, they are spaced close enough and they have some leeway, so "close" was often enough.

Custom DPL codes would work, but making sure you had one that didn't false on another legit DPL code would take some figurin'.

 

[kainixon2187]

There is not anything like what you are asking about.

Easiest way, is a Motorla DMR repeater and Motorola subscribers and utilize RAS. that will prevent unauthorized radios from accessing the system, AES256 will keep the nosey scanners out.

better yet, rc4. less secure but easily eliminates the use of scanners