MotoTRBO Restricted Access to System (RAS)

[RyanRox099]

Just found something interesting with RAS. If there is a active call going on, and the initiator of the call (with proper RAS key) lets go of PTT. A Non-RAS radio can key up with in the digital hang time and use the system. As soon as the repeater goes silent the Non-RAS radio will bonk out (gets no access to the system). I have tested this with CAP+ and digital conventional with the repeater running RAS.

 

[Forts]

That doesn't surprise me... Tailgating on an active transmission has always had some interesting side effects, especially in the P25 world.

 

[gvodvarka]

During the hang time is it possible for the none RAS radio to pass audio and keep the repeater keyed up?

 

[RyanRox099]

During the hang time is it possible for the none RAS radio to pass audio and keep the repeater keyed up?

Yes

 

[gvodvarka]

I tried to pass audio on a RAS repeater and nothing came thru. I can keep the repeater keyed up. I was also on the correct group.

 

[w2xab]

MOTOTRBO RAS

I purchased a RASS EID key for my 8400 repeater. It is interesting that radios without the RAS Key can still receive the traffic that comes from a c-Bridge.

The RAS Key can not be entered in a repeater that is configured as a Peer or DMM.

It would be a great way to keep non-MOT radios off a system and keeps others from listening without encrypting the voioce packets which would be illegal under Part 97.

 

[BamaScan]

In What version did the RAS Key Come out ?

 

[Forts]

It was around 9 or 9.5 I think.

 

[DanRollman]

I programmed a CS700 for RX only on a conventional TRBO repeater that I monitor regularly on DSD+. The CS700 screen and LED show activity on the channel but does not unmute. I'm guessing this means RAS is in use. Anyone know any way to verify the presence of RAS?

Any hardware alternatives for convenient portable monitoring of a RAS-enabled conventional TRBO repeater, given DSD+ monitors it just fine?

Thanks,
Dan

 

[Forts]

I don't believe so. RAS messes with the CRC of certain packets causing a radio without the proper key to discard the packets... Causing the radio to not unmute. DSD+ doesn't care about that stuff and will still decode the voice frames. The problem is that a system using RAS doesn't set a status bit or anything of that sort, so it's somewhat transparent. But from what you are describing it sure sounds like RAS.

 

[gvodvarka]

RAS

Today by accident I programmed my motorola radio on a RAS system and I can transmit but not receive. I can here them and me using DSDPlus. When they talk I see RAS appear in the event log but not on mine. Did someone forget to enable something on their system or is this a bug?

 

[slicerwizard]

Today by accident

Uh huh.

 

[gvodvarka]

It is a RAS system. I know the system very well. They were sold it because they were told it was secure and no one could monitor. We all know DSD lets us here all voice in the clear but what blows my mind is that I can transmit on the system. Six months ago I could not. Something has changed.

 

[Forts]

..... For starters, do you have permission to be transmitting on this system? And do other users hear you or are you just hearing yourself on DSD +?

Sent from my SM-N9005 using Tapatalk

 

[natedawg1604]

By chance, is there anything in the DSD+ terminal logs (i.e. with -v4) which would reveal the presence of RAS?

 

[slicerwizard]

what blows my mind is that I can transmit on the system. Six months ago I could not.

Another accident, no doubt.

So what system? Kinda hard to investigate without knowing which system it is.

 

[slicerwizard]

By chance, is there anything in the DSD+ terminal logs (i.e. with -v4) which would reveal the presence of RAS?

You mean the console log that scrolls like crazy? Yeah, it would be littered with "RAS" at the start and end of voice calls. Didn't Jay911 just post a dump like that in another thread?

IIRC, "RAS" should also show up in the event log if you specify detailed logging on the command line.

 

[natedawg1604]

You mean the console log that scrolls like crazy? Yeah, it would be littered with "RAS" at the start and end of voice calls. Didn't Jay911 just post a dump like that in another thread?

IIRC, "RAS" should also show up in the event log if you specify detailed logging on the command line.

Okay, but what I'm really asking is, what what part(s) of the CSBK messages or Voice Headers indicate it's using RAS?

 

[slicerwizard]

The bad checksums? Should be a dead giveaway, I would think.

 

[gvodvarka]

RAS TX

..... For starters, do you have permission to be transmitting on this system? And do other users hear you or are you just hearing yourself on DSD +?

Sent from my SM-N9005 using Tapatalk

I am their former radio tech. I still work for their parent company. I did not want to sell them Mototrbo when it first came out. I told them it was not secure and they still could be monitored. I wanted them to go P25. I do here myself thru DSDPlus using my Motorola XPR6550. I'm not sure if they can here me yet. I am going to let them know what I found. I want to try some other brands of radio to see if its a Motorola thing. When RAS upgrade was installed I could no longer here them on my radio and could not transmit. I'm just trying to figure out whats going on.