Decoding Encryption with Permission...

[SKEYGEN]

.....

 

[SKEYGEN]

The issue is (As it is with just about every discussion on secure radio systems) that there is always a vocal group with the position that today's systems are not secure enough, and therefor why both securing the system.

The "vocal group" in this case includes the people responsible for making such decisions, e.g. NIST in the USA, DSD in Australia.

When IN FACT the current technology is plenty secure for the purpose,

Current technology is plenty secure. 1970's technology isn't, hence why it's being shown the door.

and even the systems from generation or two ago are still secure enough for the purpose.

You have given no consideration whatsoever to "the purpose".

For the average beat cop or radio enthusiast, DES is still OK, only because for the moment, the effort required to break it exceeds the value of the information being broadcasted. For the feds, this is no longer the case.

 

[SKEYGEN]

No, most are being replaced as part of SYSTEM changes.

In this case, they were being replaced at that time only because of a mandate from the Defence Signals Directorate that says agencies must get rid of DES by 1 January 2005, due to security concerns.

http://www.dsd.gov.au/library/infosec/single_des.html

 

[N_Jay]

In this case, they were being replaced at that time only because of a mandate from the Defence Signals Directorate that says agencies must get rid of DES by 1 January 2005, due to security concerns.

http://www.dsd.gov.au/library/infosec/single_des.html

---------------------
Existing products

Agencies must migrate away from DES for the protection of classified Australian Government information by 1 January 2005.

Exception: Where there is no alternative to DES within legacy systems, agencies:

• must undertake a risk assessment on the continued use of DES; and

• should contact DSD for advice.
-------------------------
Looks like there is an exception available.

Of course, why invoke the exception when you can use the rule as justification to toss our your crappy sounding DES to get a brand new P25 system?

 

[N_Jay]

The "vocal group" in this case includes the people responsible for making such decisions, e.g. NIST in the USA, DSD in Australia.

I meant the vocal group here (which I doubt work for NIST or DSD).

 

[SKEYGEN]

I meant the vocal group here (which I doubt work for NIST or DSD).

The vocal group say it with good reason, and expert opinion at agencies such as those mentioned, as well as the wider security community, backs it up.

There is no cryptographic difference between DES applied to CVSD voice, and DES applied to frame relay traffic, or Ethernet, or an e-mail message etc. With that in mind, what would make you think there is somehow a security difference between DES coded traffic transported over RF rather than any other medium?

The answer to that is there is no difference in security between mediums. A cipher is a cipher, and the nature of the data protected by a particular cipher is irrelevant. CVSD voice is so widely used in everything from Bluetooth headsets to radio equipment (not just SECURENET, but a huge assortment of military radio systems) to field telephones etc that a signals intelligence agency or anyone else in the business of breaking secure communications systems isn't going to have much trouble correctly detecting a valid result. For example, near silence in CVSD has a telltale 0101010101 pattern that will essentially never be seen in encrypted data, and syllables are also fairly easy to detect. Basically, if you don't have random hash, there's a good chance you've got the key right.

 

[N_Jay]

The vocal group say it with good reason, and expert opinion at agencies such as those mentioned, as well as the wider security community, backs it up.

There is no cryptographic difference between DES applied to CVSD voice, and DES applied to frame relay traffic, or Ethernet, or an e-mail message etc. With that in mind, what would make you think there is somehow a security difference between DES coded traffic transported over RF rather than any other medium?

The answer to that is there is no difference in security between mediums. A cipher is a cipher, and the nature of the data protected by a particular cipher is irrelevant. CVSD voice is so widely used in everything from Bluetooth headsets to radio equipment (not just SECURENET, but a huge assortment of military radio systems) to field telephones etc that a signals intelligence agency or anyone else in the business of breaking secure communications systems isn't going to have much trouble correctly detecting a valid result. For example, near silence in CVSD has a telltale 0101010101 pattern that will essentially never be seen in encrypted data, and syllables are also fairly easy to detect. Basically, if you don't have random hash, there's a good chance you've got the key right.

You missed my point.

Even the (admittedly crappy) 1970's DES is "good enough" for 99.9% of the law enforcement activities (from a security standpoint), and the vocal people on this forum who like to rant on about it, seem to always get to the foolish "its not secure, so why bother" argument.
and those people don't work for NIST or DSD (and in reality don't understand the issues they like to rant on about).

 

[hotdjdave]

Alright Already

Man, oh, man, this thread/poll has taken a turn south. I cannot figure out why it has become an argument. Either you can crack the code or you can't. I know I can't even try without the proper equipment. Why gripe and complain about the fact that you or I can or can't do it because we don't have the "right" computer, the proper equipment, or the latest software?

I think Rescue161 has proven his point. It can't be done in a reasonable amount of time (or the given amount of time). I am sure it can be done eventually with non-stop processing and the proper resources (hardware, software, know-how), but it would take an amount of time that would not be within the parameters of being useful (maybe).

I keep hoping to see the real: "I got it! Here is the answer: ..."

 

[n4voxgill]

a whole lot of talking, but no one has broken the code. MYTH BUSTED

 

[rescue161]

I keep hoping to see the real: "I got it! Here is the answer: ..."

Me too!

It'll probably be a while before anyone actually figures it out though - IF they do.

 

[PJH]

This thread is still alive?

Has DES been cracked? Yes. Has DES in the radio world been cracked? Most likely, and most likely by 3 letter agencies within certain parameters.

Now for the most part, everyone has been using DES-XL for many moons, and is a varient of DES. Some of the DES rules apply, others do not which leads to another whole set of unknown variables.

The chance that someone here will be able to decode a DES or DES-XL transmission is about 1 in 100000000000000000000000000000. You would need a host of knowledge, equipment and skill (nevermind a clean signal) to get a good sample.

Would it be neat to do? Sure. But keeping the hope alive in decoding a short bit of RF traffic and able to get the key....highly unlikely.

As for the preamble, the tone isn't always there. The tone was there on certain radio models to help with radio speaker muting. It was a "hey, there is a secure transmission coming, don't open up the speaker to hear the raw hash". The ending tone heard served the same purpose, but helped to prevent a squelch crash on repeated systems. It also was not spefic to DES.

 

[loumaag]

Man, oh, man, this thread/poll has taken a turn south. I cannot figure out why it has become an argument. ...

Dave,

The reason is, everyone knows that DES transmissions are able to be monitored by those alphabet agencies in various countries. What is not being said in this thread, while ranting on how cryptographically unsecure DES is, is that (at least in the US) when a private organization comes up with a cryptologic cipher or code that they want to use, it must first be given to the government for examination and if the government thinks it is too secure, then you are banned from using it. Hence, the reason that those alphabetic agencies can monitor these "weak" codes/ciphers is that all they have to do is find the key for the code/cipher they already have in hand. No WWII Enigma comparison!

What rescue161 said in his challenge was simple, take the encoded message, break it and give it back to him in a reasonable time. This challenge was not issued to the NSA, CIA, etc., it was issued to this community; he has proved his point since no one has done so. What governments can do (since they have the technology and equipment in hand) and what individuals can do are two different matters.

To:SKEYGEN
If you are capable of decoding the message, do so, if not then I think your argumentative manner (not to mention your foul langage) is no longer desired in this thread.

 

[nolascanner]

This would be a good one for Myth Busters. So far myth is busted.

 

[MattSR]

I think its safe to say that cracking DES for radio (or any other data) is not cheap or easy for the average joe.

Big companies and governments? piece of cake..... but remember, anything is easy when your budget is large enough

 

[PJH]

I am sure its listed someone else in the thread, but it took something like 3 days with some good sized computers to crack a very small encypted computer file a few years ago.

Now, think of all the variables in an RF enviroment, and try to apply that.

In short, its not happening for the average or above average joe.

 

[n4voxgill]

almost half the people thought it would be broken in less than 24 hours. they must believe those stories of someone dated his siser and knew someone that heard that DES was easy to break.

 

[gcgrotz]

.....Some thought the Enigma would never be broken .
Thanks....

Correct me on this but did we break the code or just steal a machine or two?

There's a website somewhere I saw recently that had an Enigma machine simulator on it, I think it was from an article in Pop' Comm.

 

[N_Jay]

Correct me on this but did we break the code or just steal a machine or two?

There's a website somewhere I saw recently that had an Enigma machine simulator on it, I think it was from an article in Pop' Comm.

The machine was stolen.

 

[gcgrotz]

Hi N_Jay!

Yeah I thought so. Did you see the movie "Code Talkers"? Now that was a brilliant idea. Wouldn't you love to have been in on the meetings the Japanese had? "What do you mean you can't translate it?"

 

[N_Jay]

Hi N_Jay!

Yeah I thought so. Did you see the movie "Code Talkers"? Now that was a brilliant idea. Wouldn't you love to have been in on the meetings the Japanese had? "What do you mean you can't translate it?"

You mean Windtalkers?

http://imdb.com/title/tt0245562/

Good flick.