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Cell Phone Encryption?
Black Diamond asks: "I know I'm not up to speed on cell phone encryption, but I was wondering, are there any cell phones that let you handle the encryption from your end of things? Something along the lines of a phone you hook up to your computer to input specific encryption keys for specific contacts, as well as a private key for yourself. Is such a thing plausible, or should you trust the standard encryption that comes on some cell phones nowadays?"
This isn't exactly what you're asking about, but the closest thing I can think of offhand would be PGPfone--a product abandoned years ago for encrypting voice communications much as PGP encrypts text.
There are both binaries and source code available here: http://www.pgpi.org/products/pgpfone/
Windows and Mac only, and it's a very crude app... It would be nice for someone to develop something more robust and with better features.
Chasing Amy
(We all chase Amy...)
"The more corrupt the state, the more numerous the laws"-Tacitus
This would prevent law enforcement agencies tapping the signal.
There has to be way of 'wire tapping' any comms system according to various laws around the world so the 'good guys' can listen to the 'bad guys' (court orders etc needed).
The has been alot of stuff on the UK on this (cf ukcrypto list), the cryptos used and how it was weakened to enable 'legal' phone tapping to occur.
GSM (and PCS) phones encrypt the traffic anyway (at least they do outside the USA).
That is one of the big advantages of digital cellular modes over older, analog cellular modes - the ease of adding encryption.
However, if you want to throw another layer on top of this, it gets more difficult - since digital phones take the audio signal and vocode it, you cannot just scramble your voice and feed it in - the vocoder won't know what to do with it and won't encode it properly. You would have to inject your signal after the vocoder but before the Viterbi/Trellis coding.
www.eFax.com are spammers
i m not sure, what you are trying to ask, but that is not going to stop me from answering your question. :)
/Palm OS based cell phone, then there are some encryption apps out there that can help you. Here are some links:
http://www.softwinter.com/sentry_ce.htmlw ww.f-secure.com/wireless/pocketpc/pocketpc -fc.shtml
Are you asking about encrypting the data stored on your fone? or encrypting the data transfer between your fone and your service provider?
If it is a Pocket PC
http://www.pointsec.com/core/default.asp
http://
However good encryption/decryption take up lots of CPU power, so I dont know how feasible it is to ecrypt all the data on your cell phone.
Consensus is good, but informed dictatorship is better
If my memory serves me correctly, CDMA is a form of spread-spectrum modulation. It's fairly resistant to evesdropping by your average crook, although there's no doubt that big brother can tune in if he wants. Hell he doesn't even necessarily need to receive your signal, he could have the phone company tap it at the cell site. I don't know much about other types of cell phones.
One thing you could do, if you can use your cell phone as a modem (I think most digital phones can do this at fairly high speed) then you can just iphone or something similar but tunnel the stream through an encryption layer. It would probably be better to apply encryption within the codec, and use some type of encryption that is highly tolerant of dropped packets, thus enabling you to use UDP streams.
I guess I don't know of anything like this off the top of my head.
-73, de n1ywb
www.n1ywb.com
No they don't.
(a) Both GSM and CDMA encryption are flawed and can be broken.
(b) It doesn't matter if the encryption is bad, all GSM phones listen for a single bit from the tower they're communicating with that tells it if it should encrypt or not. It is trivial for anyone with the resources to eavesdrop on a digital phone call to setup their own fake tower to tell your phone to turn encryption off.
(c) so what if mobile phones encrypt, phone lines that they connect to don't.
never trust commercial "encryption" to be anything more than the magic decoder ring from your cerial box wrapped in a DMCA wrapper calling anyone that points out that its made of cheap injection molded plastic an information terrorist.
It is trivial for anybody with the resources to build a faster than light drive, too - for some definitions of "with the resources".
It would depend upon whom this guy wishes to protect his conversations against - J. Random Carbonunit or Special Agent TLA.
If the former, than the encryption used in GSM is enough - few people have the gear to modulate and demodulate a GSM signal with proper time slotting, time of flight correction, etc. Making a GSM signal is HARD - I build gear that does it.
If the latter, then they won't screw around picking the signal off the air - they will throw a CALEA intercept on his phone when it hits the PTSN. Then the only thing that can protect him would be VERY strong encryption seperate from the phone - which as I said in my first posting is difficult due to the nature of digital phones.
Lastly, if he is trying to protect himself from Special Agent TLA, encrypting his signal like this won't help - it will just raise a big red flag saying "Look At Me! I Am Hiding SomeThing!". He would be far better served making an innocuous word code and using that.
www.eFax.com are spammers
Ok, so I want to easedrop on you and i have alot of resources. I'm going to put up some renegade cell phone tower that will overpower the legit tower and provide service to thousands of people... and I'll do this all over an area or city?
It would be easier to follow you with a parabolic microphone.
My recommendation to you is to tighten your tinfoil hat.
Conformity is the jailer of freedom and enemy of growth. -JFK
I just do a Darth Vader imitation and speak in Pig Latin. Since I started doing this I haven't been hassled by The Man once!
(Posted anonymously as I work in this area).
As far as I know, none of the UK mobile companies encrypt over the air anyhow (if you have engineer mode enabled on your phone you can easily prove this).
Even if they did, it matters not how easily the crypto can be broken, as the voice data is only encrypted up to the base station anyhow. The network operator taps the call after it's decoded and while it passes through the network 'in the clear'.
As a previous poster pointed out, legal requirements mean that the operator has to do this.
You can buy a modified version of the S35i that does station-to-station strong encrption. Do a Google on "Siemens TopSec".
-psy
But not in the form you say. There exist chips which will do a Diffie-Hellman exchange to set up a secret key, and then do AES encryption on the whole conversation. Comes as a Sony-Ericsson accessory.
Of course, lack of standard make these chips non-interoperable (not encryption/decryption but key management). Once it becomes popular standards need to emerge.
beautifully worded! *applause*
I've used some of the gear you build and I can't see how this is trivial by any measure.
Unless you enjoy designing custom analog/digital hardware, there is just no way you're going to override the single byte in a stream that selects clear encoding, and then just listen to a clear channel conversation. The "man in the middle" attack is your only hope for using off the shelf toys. You'll need proper amps., a sharply directional antenna, and GSM phone-test-set that will exchange two-way pcm data with sufficient programability to allow you to emulate the mark's usual carrier signature, and a GSM test phone that outputs it's received PCM data in digital format so you don't have to go analog to digital again (which would sound atrocious given the kinds of compression involved).
Assume you could get these things, expand their capabilities and get them to communicate smoothly, you still wouldn't get the right caller ID unless you intercepted the challenge going to your test phone SIM from the carrier and repeated it to the mark's phone so you could be seen as having his IMSI. That would be yet another awesome hack to your credit.
And then of course you'd have to follow conspicuously closely to keep the mark from stepping behind something that blocked your signal (extra power won't help much in the microwave band).
Until we all start using it, encrypting your voice signal would certainly just shout "I'm hiding something."
If you want one of these conversations from your GSM phone, I'd go somewhere where they had GPRS or another GSM enabled data access method and send seriously encrypted VOIP traffic. If you want stealth, pick a location where you can get multiple GPRS timeslots (some phones support up to 128k bits) and package your voice in an encrypted stream like SSH. No one would think it unusual for a computer geek to ssh into his server from the field. The fact that one of your socket connections was a VOIP stream wouldn't be externally detectable.
just learn Navajo. Works for some people.
(a) Both GSM and CDMA encryption are flawed and can be broken.
I'm not sure which CDMA encryption you are talking about, but using a phone like this would make breaking its encryption a hard feat to accomplish.
'A lie if repeated often enough, becomes the truth.' - Goebbels
Take a look at the Tiger GSM phone from Sectra.
Check out the Qualcomm QSec-800 for a CDMA equivalent of the Siemens TopSec, although you might have to work for the government to get one for now anyway.
> If the latter, then they won't screw around picking the signal off the air - they will throw a CALEA intercept on his phone when it hits the PTSN.
This is why the encryption needs to be end-to-end, all the way from your terminal to the callee's terminal. Otherwise it's about as useless as "VPNs" that connect you to unencrypted corporate networks.
I know that Motorola just released an addon to a off-the-slef phone that adds comsec.
s /g eneral_dynamics_sectera_secure.htm
From what I understand, phones with this devices are aproved by NSA for secret transmittions.
Doing a google seach I came up with this:
http://www.cellular.co.za/phones/generaldynamic
hmm... for fun I enjoy launching DDoS attacks against 127.87.42.5
Rhode+Schwarz offers GSM mobiles with encryption and PCMCIA cards for GSM mobiles. Ironically, it manufactures also so-called IMSI catchers, which allows secret services and other "authorities" to intercept any GSM mobile.
By the way, GSM is encrypted by default, but the providers can switch that off at any time without notification
How is this flamebait.. This is a perfectly valid opinion, and valid response to someone else's post.
Just like half of Slashdot User's sigs say, Instead of being lazy and modding me down, post an intelligent response.
[DISCLAIMER: This post is a work of satire and should not be misconstrued as a holy text upon which to base a religion.]
This company used to, and still does (I think) make good encryption add-ons for cell phones and radios. Don't know much about how to purchase them or what quals. you have to have to buy, but you certainly should give them a call to ask.
This company used to (and still does I think) make encryption devices for cell phones and radios. I'm sure they'd be happy to tell you how to buy their products. :)
http://www.transcrypt.com/
...the only way to do it would be to manage it via a computer-like device connected to your phone and then use GPRS or somesuch to send the data through your mobile phone.
What about the other end, you say?
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... and clueless marketroids who don't know the difference between 1038 and ten-to-the-38th-power.
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