InterceptRadio.com Forums

A very interesting article about the lack of P25's security and robustness.



Article link: http://blogs.wsj.com/digits/2011/08/10/ ... sdropping/

Here's the PDF link to the study: http://online.wsj.com/public/resources/ ... 102011.pdf

Here's another PDF to a study done last year: http://repository.upenn.edu/cgi/viewcon ... is_reports

Funny, I don't see how P25 is )or was sold to be) "more secure" than FM, and in the case of FM, the same can happen.

i painted all my radios pink

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This seems to be a "repeated" issue as far as agencies/cities having problems with P25 and radio communications across the country. Seems like these cities/counties/states all fell for the "fear mongering" of radio communications sales people and large communications companies. Seems to me that the majority of these agencies/cities/counties would have been much better off with a "reworking" if you will of the current systems or switching to other non trunked/or P25 digital options.
I have read repeatedly on various boards/forums about numerous agencies that have "worse" issues after switching to P25/digital systems than they ever had with the old systems. Seems like we just need to get back to "the basics" of radio communications to alleviate many of these issues. Aren't there many options with UHF/VHF systems that could be implemented that still utilize certain "secure" channels as needed as well as interop and cross system communications??
As well as saving cities/counties/states boatloads of money in the process and still have a good strong radio system.
Just my own thoughts on this. Seems to me that there are still many "good" well working radio systems in place throughout the country in many states that can work as well as IF NOT BETTER than a large complicated multi-tiered radio system.

The systems I know that do P25 awesome are like Bell FleetNet in Ontario...which spans half of the province with 3 separate systems.

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P25 was sold to be "secure" to the federal government. Motorola did the selling here but they purchased it as being secure. That's what the DES encryption is used for...

FM can be jammed -- sure -- but a good "jammer" requires sufficient power and would be relatively easy to DF. The point of the pager was that it was fairly low power and it was a hacked toy product.

I think their study is fair in that 1. user's are not being properly trained and/or don't care about security and 2. they are some design flaws in the P25 system which should be addressed in a future update. (Perhaps they already are, I dunno.)

When I first read about the Motorola radios back in 2001 I was rather surprised to learn that the "encryption" mode was something had to be turned on manually. You would think federal LE would want their radios fully-encrypted 24/7.

You do not have to "turn on or off" the encryption. It is the programmer's choice if they want to activate that "feature" Some agencies like to be able encrypt when needed, some want it all the time.

It can be remedied by not allowing the users to turn off the encryption in less than a few keystrokes.

I had an occasion to converse with a Navy SEAL about their Motorola handhelds equipped with DES encryption. Granted, this was 20 years ago
and much has changed... but they still elected to operate "in the clear" as much as possible as the DES would eat the batteries and greatly reduced their effective communications range.

Eric
KB7DQH

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That is how the people at DARPA think. they take things and use them in unconventional ways, to see what happens.

Encryption still affects range, although how much compared to then???
Turning your radio ON tends to cause batteries to drain.

Can we alternatively title this "Alice and Bob meet Mallory"?

:mrgreen:

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President-in-Exile, Seattle Area Radio Communications And Scanner Traffic Intercept Crew (SARCASTIC)
Don't feel bad if you can't use your STD100/200; there are still people using Digital Frequency Search!
Bunnery definition for the under-fives

Yes.

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The manufacturer courses broach this subject often (although probably tainted.) The argument is that digital is digital no matter in what arrangement the 1's and 0's get there from here.

They claim to us that p25 encrypted or not has the same coverage.

I have had no experience with encrypted p25 so cant comment otherwise..

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."

It depends on the complexity of the encryption algorithm and can also depend on timing. Digital audio, in its simplest form, is a stream of values to represent voltage. You can knock off a few data points and still reasonably complete D/A conversion especially at higher sample rates. The problem with encryption is that many algorithms are not 1:1 for byte-in and byte-out, therefore a minimal bit error rate can corrupt entire packets of data.

Its never that complex when they are trying to teach you to sell radios...

Im gonna be in class in a few weeks and Ill have to "broach" this subject again... see how much trouble I can cause... :mrgreen:

Thanks for your explanation Rich! :wink:

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"A well regulated breakfast, being necessary to the healthy start of the day, the right of the people to keep and eat food shall not be infringed."