traffic analysis (was: blackmail / stego)

[Antonomasia]

From: "John S. Denker" <jsd at av8n.com>

> It is true that if you design an "anonymity" system
> under the assumption that the opposition doesn't
> have enough resources to perform traffic analysis,
> you'll be taken to the cleaners if the opposition
> does have such resources.

I think it's likely that an anonymity server was given special attention
by the FBI.  If the story's accurate this guy probably put himself at
greater risk by using one.

> There exist well-known techniques for greatly
> reducing the effectiveness of traffic analysis.
> 
> A scenario of relevance to the present discussion
> goes like this:

The crook demands a text message sent to a widely-carried newsgroup.
This can be noted down in an internet cafe while viewing it via google.

To say nothing of the fact that distribution of the card secret is desirable.
Risk of apprehension at an ATM could be reduced (at a cost in other risks)
by manufacturing numerous cards and posting them (smartly presented) to
random people as a supposed offer.
    Your card has been approved - withdrawals from your account are
    interest free for the first month.
The flood of people emptying ATMs over a wide area should keep Plod busy.

Or demo one card in a cut+choose manner and sell the rest to a crook
who doesn't know you.  He then carries the risk of visiting ATMs (and the
weight of e200,000).

The sum involved is funny.  It's not enough to be a once-in-a-lifetime
big crime unless he's trying to get out (once) from e150,000 debt.

But what do I know ?  I'm still working.

-- 
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# Antonomasia   ant notatla.org.uk                           #
# See http://www.notatla.org.uk/                             #
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