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Secure Voice Communications While Travelling?

Posted by Cliff on from the thwarting-eavesdroppers-everywhere dept.

captnitro asks: "My father works for the US Dept of Commerce in the Eastern Bloc. His hotel room phones are routinely bugged -- a few (former) coworkers have had their stays 'shortened' and politely asked to leave the country, when they said dumb things over the phone. A few days ago he asked me what I use for secure voice when I don't have broadband. Remembering PGPfone from a while back, I looked up the link, but apparently they're no longer supporting/distributing it. While I wouldn't recommend he say much of anything in a bugged room, it got me thinking -- what do *you* use for simple, no-nonsense (requiring modem + sound card), low-bandwidth secure voice app? Unix works, and scriptability gets geek points, but I'll take what I can get."

4 of 85 comments (clear)

  1. Analog Hole by zulux · · Score: 4, Insightful

    Voice has a *huge* analog hole - any microphone within 100 ft can pick the converation up, and parabolic dish or laser bounched off the window can extand that range to blocks.

    So given that you want to be secure, you *really* have to rule out speach.

    So try IM.

    --

    Moneyed corporations, non-working 'poor' and criminal prisoners are turning productive citizens into tax-slaves.

  2. Be aware of the risk by Piquan · · Score: 3, Insightful
    Remember that no matter what you do, there's risks. Encrypt a voice connection? A room bug will have no trouble listening to that. Even if the room itself has no transmitters, somebody can point a laser at the window and hear what's up. Besides, the encryption doesn't buy you great security: to the NSA, encrypted phone calls are pretty much a joke.

    Email may be better. It stands up to cryptanalysis better, and room bugs don't get it. But, it is vulnerable to a lot of new problems: Van Eck emissions, screen flicker, and even a good ol' pair of binoculars across the street.

    If you use these, remember that the security of the mechanism is only as good as the security of the computer. If you get 0wnz0r3d, then you're screwed.

    Now, consider the idea of "proportional response". Right now, your dad gets phone taps. What do you think will happen if he starts encrypting communication? Sure, a regular phone tap falls apart under almost any sort of encryption. But start using encryption, and they're more likely to put more resources into finding out what you're up to. That's when the things like room bugs and Van Eck attacks come into play.

    So, you have to figure out: how much of a risk does your dad represent to them? How much are they willing to spend to monitor his communications? That's the first step to deciding what appropriate encryption would be.

  3. Isn't the government good at that sort of thing??? by Tintivilus · · Score: 3, Insightful

    He's a government employee; I'd expect that if they wanted his communications to be secure, they would be. I'm sure they have all kinds of nifty toys that are provided to those they think need them.

  4. NSK 200 - Secure GSM/DECT phone by neonstz · · Score: 3, Insightful

    If you really want to get secure you should take a look at the NSK 200, a GSM/DECT-phone which is approved for NATO Secret. I don't know if it is available for everyone though.