Hi Jay.
Date: Thu, 23 Nov 1995 00:17:47 -0800 From: Jay Campbell <edge@got.net> Subject: Re: crypto for porno users
A law enforcement team would be stepping onto shaky ground if they were forced to transfer illegal images/etc to a suspected trafficer before getting evidence from him. Entrapment is an ugly concept.
We've been hearing about such things (using the mails) for some time. I don't know how the cops avoided entrapment when they posed as kiddie porn customers or pedophiles when they were doing the AOL sting.
3. Encryption of porn would work against the kind of porn distribution found on the alt.binary.pictures.erotic... newsgroups. Encryption requires that recipients be identified.
Not at all .. a porn distributor could generate a key pair, use part A to encode the images, and dessiminate part B thru a variety of outlets - publicly posted, sold, passed thru an informal network of like-minded netizens...
It's that informal network which is the danger to the pornographer. The bigger the network, the closer to certainty that it's been infiltrated. <begin major soap box issue for me> Strong authentication via crypto does not create a trusted group. Trust is a human:human decision -- subject to severe flaws, none of which are solved by crypto. [Can you devise a crypto protocol which will prevent or even just detect adultery, for example?] With each additional person, there is a probability of deception. For this informal network of yours, deception by any one participant constitutes a security failure. If you want to avoid that, therefore, you need to keep the group *very small*. If it's that small, then it's not that interesting a target for LE. <end major soap box issue for me>
I would argue the exact opposite - strong crypto would tend to minimize the effective take, since there's no guarantee that /anything/ on a perp's system will be in the clear. I'll let someone else with a better background pound on the 'brute force' section.
Ah -- but that's the point I was making. Crypto gives the appearance of security -- whether it's in the informal network or with file storage. It's often a bank vault door on a cardboard house. For much of what people do, especially if there's a large net, it's not rational to expect to achieve security. But -- if people have done something to achieve security, they're likely to be fooled into trusting it to be adequate. Meanwhile, if *everything* on the perp's machine is encrypted, you're probably in good shape. That means he'll be required to type passwords too often -- so he'll either pick a small one or have some machinery which stores the password. Both give cryptanalytic advantages. This isn't a guarantee that *every* perp will be wide open. Some won't be. It means that a bunch of perps will be wide open (out of their own carelessness -- like the breaks into the Enigma net). The question you need to look at is not the control-freak question which Freeh seems concerned with: A) the probability that some one perp will manage to hide his data but rather the SIGINT question: B) the expected percentage of perps who will fail to hide their data Have a good day. - Carl +--------------------------------------------------------------------------+ |Carl M. Ellison cme@acm.org http://www.clark.net/pub/cme | |PGP: E0414C79B5AF36750217BC1A57386478 & 61E2DE7FCB9D7984E9C8048BA63221A2 | | ``Officer, officer, arrest that man! He's whistling a dirty song.'' | +---------------------------------------------- Jean Ellison (aka Mother) -+