Re: [Cryptography] prism-proof email in the degenerate case
* John Denker [2013-10-10 17:13 -0700]: > *) Each server should publish a public key for "/dev/null" so that > users can send cover traffic upstream to the server, without > worrying that it might waste downstream bandwidth. > > This is crucial for deniabililty: If the rubber-hose guy accuses > me of replying to ABC during the XYZ crisis, I can just shrug and > say it was cover traffic. If the server deletes cover traffic, the nsa just needs to subscribe. Then the messages which you sent but which were not delivered via the list are cover traffic. Nicolas -- http://www.rachinsky.de/nicolas ___ The cryptography mailing list cryptography@metzdowd.com http://www.metzdowd.com/mailman/listinfo/cryptography
Re: padlocks with backdoors - TSA approved
* Hadmut Danisch <[EMAIL PROTECTED]> [2007-02-26 21:20 +0100]: > has this been mentioned here before? I don't know if it was mentioned here. Bruce Schneier wrote about it some time ago. http://www.schneier.com/crypto-gram-0404.html#2 http://www.schneier.com/crypto-gram-0405.html#10 Nicolas - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]
Re: NPR : E-Mail Encryption Rare in Everyday Use
* Ed Gerck <[EMAIL PROTECTED]> [2006-02-25 13:11 -0800]: > Finally, the properties of MY public-key will directly affect the > confidentiality > properties of YOUR envelope. For example, if (on purpose or by force) my > public-key > enables a covert channel (eg, weak key, key escrow, shared private key), > YOUR > envelope is compromised from the start and you have no way of knowing it. > This is > quite different from an address, which single purpose is to route the > communication. > > That's I said the postal analogue of the public-key is the envelope. I don't agree with that analogue. An paper envelope does not prevent anybody from opening it (you can open it without any tools and with nearly no effort). The encryption should make it impossible for anybody to see the contents. The recipient might detect that the envelope was opened or replaced, but you must trust that he will detect this (you can't check it yourself). Nicolas -- http://www.rachinsky.de/nicolas - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]
Re: Fermat's primality test vs. Miller-Rabin
* Joseph Ashwood <[EMAIL PROTECTED]> [2005-11-22 02:50 -0800]: > - Original Message - > From: "Anton Stiglic" <[EMAIL PROTECTED]> > Subject: RE: Fermat's primality test vs. Miller-Rabin > > > >-Original Message- > >From: [Joseph Ashwood] > >Subject: Re: Fermat's primality test vs. Miller-Rabin > >>I think much of the problem is the way the number is being applied. Giving > >>a stream of random numbers that have passed a single round of MR you will > >>find that very close to 50% of them are not prime, this does not mean that > >>it passes 50% of the numbers (the 2^-80 probability given above is of this > >>type). > > > >Do you do an initial sieving to get rid of the more obvious primes? > > No I did not, since this was specifically to test the effectiveness of MR I > determined that it would be better to test purely based on MR, and not use > any sieving. The actual algorithm was: > > > 16384 times > { >question = random 512-bit number >//this is not the most efficient, but it should remove bias making this > just MR If I remember the proof of MR correctly it assumes an odd number. Were all your questions odd? If not, please try again with odd numbers only. Nicolas - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]
Re: Ostiary
* Karl Chen <[EMAIL PROTECTED]> [2005-08-02 09:24 -0700]: > As an authentication protocol, it looks vulnerable to a time > synchronization attack: an attacker that can desynchronize the server > and client's clocks predictably can block the client's authentication > and use it as his own. (Assuming the server's clock is monotonically I don't see where the client's time is used. What am I missing? Nicolas PS: Why is this list blocking my mail if the envelope-from is not subscribed? [Moderator's note: there is this little known phenomenon called "spam" we like to avoid... it is much harder to moderate a list if you have to wade through 400 garbage messages a day... --Perry] - The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]