Encryption has started.

[INDY72]

Now as to old voice inversion,.. there is a scanner that is on ebay right now that defeats it. That is why anyone that still uses inversion needs to upgrade to a form of encryption.

 

[WayneH]

Here's the part that we're interested in for this thread:

Now if the IMBE voice is encrypted we are out of luck, sort of... APCO-25 calls for a the DES encryption method with 56bit keys. I guess there are public domain DES rotines out there, anyone what to try and decode a DES encrypted call, might take years. I have a theory, since I have noticed that IMBE voice calls always begin and end with a fixed pattern we have information that makes it tons easier to decrypt. We can try different keys on the data until it matches this fixed pattern at the begining and end of the IMBE voice call... once we have the key its simple to run the DES decoder and get the raw unencrypted IMBE voice data.

Sounds wonderful, doesn't it? Well unfortunately for this guy (and the rest of us) Motorola was smarter than that. I know, I know... total bummer.

Huh? Motorola didn't develop the APCO-25 standard, nor DES encryption. He basically states that if one was to attempt to crack the encrypted voice portion that it would be much easier than doing a standard DES crack. Also, OSPs are flagged as encrypted or clear. The scanner doesn't need to examine the data stream for any kind of pattern; that's not realistic due to the amount of analyzing required. There's no frequency threshold since it's all 1s and 0s. My 96 never stops on an encrypted call, it only does if the call goes from clear to encrypted without repeater dekey, which can also be prevented.

In addition, AES is the current encryption standard and will no doubt be the norm for any future Motorola trunked or conventional system using encryption. It's what their Sales is pushing now.

You'll also have to code in the algorithm for IMBE so you can turn the bits you somehow managed to decrypt into voice. Running it back into a scanner isn't realistic (waaay too much trouble); it's easiest to write the code to decode the voice. AND, yes, you will need a fast computer to crack DES. If DES was that easy to crack with a slow computer then it would have been done years ago with a 386 (Any 'old computer,' give me a break!!). AZScanner, you really need to read more into it as you're passing way too much amateur judgement. Try some of the common password cracking programs out there and even with a P4 whatever it will still take time. So no, you won't be burning a CD, listening to net music, and cracking DES all at the same time with your home PC. In this application you have several more steps to take care of compared to cracking some encrypted data on a computer.

In reality it's only worth doing to do it. Any properly encrypted communications system will rotate their key on a timely basis. This is very common for the Feds. For trunked systems like Orange County, CA they, no doubt, with an infrastructure managed encryption key system, rotate it periodically.

Also, there are forms of inversion out there that the common descramblers such as made by Ramsey, or the AOR plug-in, or the software app INVERT cannot descramble. The forms are easier to crack if you try but they still provide secure comms to any common scannist.

-Wayne

 

[mdfillipp]

I always love it when wayne speaks: it just makes more sense and clears everything up.

I'm glad you brought up my area's system. While we are on the subject, wayne, how much trouble would, or will, it be to convert an existing P25 3600 smartzone system using des-ofb, such as OC's, into one using aes, in terms of time, money and/or effort?

 

[WayneH]

I always love it when wayne speaks: it just makes more sense and clears everything up.

I'm glad you brought up my area's system. While we are on the subject, wayne, how much trouble would, or will, it be to convert an existing P25 3600 smartzone system using des-ofb, such as OC's, into one using aes, in terms of time, money and/or effort?

:lol: :wink: I'm not sure of costs but you'll need to upgrade the key management server so it can properly load AES keys, replace every encryption module in each subscriber unit, update the DIUs for the consoles, and if there are any, upgrade the handheld key loaders (similarly to how the KMF is).

Nothing really needs to be done to the infrastructure other than upgrading the KMF. Where the serious money is are the encryption modules since you have to buy new ones. Considering how many radios are out there that need the modules, say....5-6,000?, modules costing probably $700-900 at a Gov. rate; then to replace them you have to pull out each radio, open it up, and swap out the module. It's quite an undertaking. I would side with them NOT upgrading as they seem to have the security they need and I'm sure they still aren't doing spectacular with finances.

-Wayne

 

[dizwiz]

What I see happening wiht encryption is that criminals/terrorists/etc. will jam communications as opposed to attempting to decrypt them.

 

[AZScanner]

Huh? Motorola didn't develop the APCO-25 standard, nor DES encryption. He basically states that if one was to attempt to crack the encrypted voice portion that it would be much easier than doing a standard DES crack. Also, OSPs are flagged as encrypted or clear. The scanner doesn't need to examine the data stream for any kind of pattern; that's not realistic due to the amount of analyzing required. There's no frequency threshold since it's all 1s and 0s. My 96 never stops on an encrypted call, it only does if the call goes from clear to encrypted without repeater dekey, which can also be prevented.

You'll also have to code in the algorithm for IMBE so you can turn the bits you somehow managed to decrypt into voice. Running it back into a scanner isn't realistic (waaay too much trouble); it's easiest to write the code to decode the voice. AND, yes, you will need a fast computer to crack DES. If DES was that easy to crack with a slow computer then it would have been done years ago with a 386 (Any 'old computer,' give me a break!!). AZScanner, you really need to read more into it as you're passing way too much amateur judgement. Try some of the common password cracking programs out there and even with a P4 whatever it will still take time. So no, you won't be burning a CD, listening to net music, and cracking DES all at the same time with your home PC. In this application you have several more steps to take care of compared to cracking some encrypted data on a computer.

-Wayne

Well bravo for you Wayne, you sure put me in my place. :roll:

-AZ

 

[Heterodyne]

This thread is the funniest thread ever.

 

[N_Jay]

This thread is the funniest thread ever.

Funny; HaHa

Or

Funny; Does this smell Funny?

Or

Funny; Stay away from that guy, he is acting kind of funny! :twisted:

 

[WayneH]

Well bravo for you Wayne, you sure put me in my place. :roll:

-AZ

People ask questions because they want answers, correct answers. If someone isn't familiar with the topic of the question and doesn't know, DON'T answer it. :roll: If you take offense then sorry, but you weren't completely correct.....and you got called on it.

-Wayne

 

[SCPD]

Does anyone here on this thread have the means, and capability, to decrypt an encrypted signal? With all of the encryption possibilities out there I don't believe it would be feasible to pursue it. I don't even sweat the issue because I don't have the time, capability, or the funding for it.

Let's take a look at digital encryption for a moment. D.E.S. Data Encryption Standard. 56 bit encryption. About five years ago D.E.S. was broken using a custom made computer, costing almost $250,000, and it took alittle over 22 hours to break a message. Do a google search for R.S.A. and read all the details.

D.E.S. is rather dated being that it came on the scene around 1977. It's probably still okay for some users but Uncle Sam doesn't think so. We now have Triple D.E.S., A.E.S., Fascinator, etc.

When I was in the military I was assigned to one of the alphabet soup agencies. Back then we used Motorola MX350S' ,with D.E.S., and we keyed loaded each radio once a week. Eventually this agency went to Saber radios, with O.T.R. capabilty, and would re-key everyday. Presently, their security ops use full time encryption and re-key over the air once a day.

So, is it worth the time and effort to decrypt a signal? Maybe if you have the time, money, and want to carry a computer around with you. Would you want to wait almost a full day to find out what was said? Not me. I could probably find out on what happened via the evening news alot faster. Just remember, these agencies spent alot of money to keep their message content private. How much money do you have to find out what they want to keep private?

 

[mdfillipp]

Nice lecture, Professor.

 

[SolarisZen]

So you guys say that enccryption will still be not used all over the place. Does that mean that PS will stay the way they are and not upgrade anymore or does that mean that ordinary PS will join special units and the military to encrypted signals, just not FD and EMS?

 

[GlacierClipper]

It is being used constantly by the governemnt and in the private sector each day.

 

[SCPD]

When I was in the military I was assigned to one of the alphabet soup agencies. Back then we used Motorola MX350S' ,with D.E.S., and we keyed loaded each radio once a week. Eventually this agency went to Saber radios, with O.T.R. capabilty, and would re-key everyday. Presently, their security ops use full time encryption and re-key over the air once a day.

Warning: academic discussion follows.

OTAR is certainly more than adequate security for most "tactical" government communications. However, it is actually less secure than the manual weekly keyload procedure described above. The weak link is in the radios. There is a key programmed into the radio that enables it to accept these OTAR commands. Instead of cracking the key used to encrypt daily comms, a "spook" could target the key used by the radio's firmware to support OTAR keyloading.

Even then it would be very difficult.

-rick

 

[yagigain]

Couple of points,

1) Over here in Australia some states are now Encrypting ALL police communications, starting in Adelaide in South Australia and now Brisbaine in Queensland, with Melbourne, Victoria planning to Encrypt Police communications by 2006 and then even Fire and Ambulance and NSW starting. No public feeds or internet streams either.
All the media are being offered is basically to be informed in some way by the police departments of events that are 'news worthy'.

The Queensland Media have taken the Queensland Police to court regarding this issue.

http://www.cmc.qld.gov.au/PRC_INQUIRY.html

2) Decrypting signals in Australia, at this time, does not appear to be illegal. Even though head on raw decryption could be a slow process .. maybe not ... think SETI .. i.e parrallel computing.

 

[Jay911]

scan your input frequencies....

With all due respect, what is this going to accomplish, except make you hear less of the transmissions, since you won't hear the farther-away radios?

I realize I'm replying to an old post here, but the radios around here, which are far from state-of-the-art, do the encryption on-board, not at the repeater/trunk site. The signal going to the repeater or trunk repeater will be just as indecipherable as the one coming out the other end.

 

[grem467]

i dont know of ANY radio system that makes the repeater responsible for the encrypting of signals, yes some analog securenet repeaters are keyloaded, but thats used more to keep people with the wrong key out.

in astro, the quantar/quantro just passes along whatever key the subscriber units are using..

 

[jparks29]

a comment about someone "suggesting" using AES ... its been reported(shall I say leaked) . that AES has some inherent security flaws.... that the "gubberment" is responsible for...... instant backdoor... just remember.. hide in plain site.. makes you look less suspicious

 

[AirportTek]

Encryption Comments

I know this is an old thread, but in my State we have voluntary and mandatory taxes. Our entire PD TG's are now encrypted. I wrote the Mayor and Cheif of Police and have decided I will no longer pay the Voluntary taxes nor will I vote for increases in PD pay, tax increases for the jail or any other ballot item that will benefit the PD, I don't think they need it because I listen to my scanner I hear the PD doing NOTHING due to their encryption so I no longer have any reason to believe the PD needs more money, especially since they drive their cute little Camaros now. With encryption it just makes it easier for them to hang out at IHOP or the Donut Shop without the taxpaying publics knowledge. Police Band has been on radios even back to the days of tube radios. I have many radios from the 1940's which have police band on them. Sensitive info should be encrypted, Normal dispatch traffic should not.

 

[MacombMonitor]

Just buy one of those Darth Vader mask, with the voice-changer, and you're good to go! :lol: