Password Difficulties
Hey folks, passwords are hard to choose! It boils down to this: I can't remember as many bits as the TLAs can crack by brute force. Starting with a bunch of coin tosses I tried ways of coding them: hex, ASCII, and words off word lists. Horrors! The hex is too long, the ASCII is too long and too obscure, words words chosen by those bits too many and too obscure. Sorry, there is no way regular people are going to remember pass words or phrases with more than about 50-bits worth of information in them--and even doing that well is going to be rare. We need to slowdown password testing? Obvious things come to mind. 1) Try to pair up short passwords with slow hardware, like a smartcard that can only consider a few passwords a second. 2) Try to hide behind an expensive operation. (Does encrypting my private key 1,000,000-times equal encrypting it once with a key 20-bits longer?) What do we do? (What are you folks doing right now?) -kb, the Kent who occasionally considers practicalities -- Kent Borg +1 (617) 776-6899 kentborg@world.std.com kentborg@aol.com Proud to claim 31:15 hours of TV viewing so far in 1994!
It boils down to this: I can't remember as many bits as the TLAs can crack by brute force.
Have you *tried* to memorize these long passphrases? I pick ones that are substantially too complex for me to memorize in one trial. So I write the candidate passphrase on paper until I have a grasp on it, then burn the paper, scatter the ashes (yes, literally), and begin to use the passphrase. My experience is that once I've successfully remembered a phrase two or three times, I will not forget it. This approach is vulnerable to anyone who is able to snoop around my belongings, but at that point they might just as well do what they did to Ames. I hardly think I warrant this kind of attention. Eli ebrandt@hmc.edu
On Sat, 2 Jul 1994, Eli Brandt wrote:
It boils down to this: I can't remember as many bits as the TLAs can crack by brute force.
Have you *tried* to memorize these long passphrases? I pick ones that are substantially too complex for me to memorize in one trial. So I write the candidate passphrase on paper until I have a grasp on it, then burn the paper, scatter the ashes (yes, literally), and begin to use the passphrase. My experience is that once I've successfully remembered a phrase two or three times, I will not forget it. ...
I have actually tried memorizing truly random passwords of 8 characters or longer (generated with a paranoid program similar to PGP 2.6's excellent technique). I've found that if I review it enough, that I find patterns and mnemonic clues in such passwords that help me to remember them. I don't imagine too many people will go through that effort, so I still think that a longer pass phrase that sort of "makes sense" is better for a PGP key. Still, I do use the truly random passwords on publicly accessible Unix systems like CSN, since that makes dictionary attacks improbable.
Hey folks, passwords are hard to choose!
?
It boils down to this: I can't remember as many bits as the TLAs can crack by brute force.
I generally choose things like (no, this is not a real one): Rare steak tastes good when it is cooked over a wood fire. better than chicken. better than fish. good with worcestershire sauce. this is for a pgp passphrase, of course. I find it not to be a problem remembering a sentence character for character.
Starting with a bunch of coin tosses I tried ways of coding them: hex, ASCII, and words off word lists.
Horrors! The hex is too long, ....
Sorry, there is no way regular people are going to remember pass words or phrases with more than about 50-bits worth of information in them--and even doing that well is going to be rare.
? josh
On Sat, 2 Jul 1994, joshua geller wrote:
[. . .]
It boils down to this: I can't remember as many bits as the TLAs can crack by brute force.
I generally choose things like (no, this is not a real one):
Rare steak tastes good when it is cooked over a wood fire. better than chicken. better than fish. good with worcestershire sauce.
You can improve entropy even more, and still keep it memorable, by doing something such as the following: Rare 513AK tastes g))d when it is c))K#D over a wood fjord. BETTERthanCHICKEN.... Using poor or improper English--or some other language--will also help. So now, we might have: Viva dA5 bu0n) Rare 513AK tastes w3#l it when 15 c))k#D.... You, of course, will have to be the judge of how much mutilation you can remember. And note that, while such changes will help with passphrases, any sophisticated dictionary/algorithm-based password (>8 charcters) cracker will be able to guess most of them. "f43d" is no more secure than "fred." Better to hit random keys on the keyboard or use a true random number generator--flip a coin 56 times to get a 7-bit ASCII string, more if you get control characters--to get your eight characters, and just force yourself to remember it. Even something like "g&*3VkjH" is memorable--I did use that one for a couple weeks some months ago. Speaking of which, are there any /bin/passwd plugins that use passphrases rather than passwords? Or should I be a good cypherpunk and write some code?
[. . .] josh
b& -- Ben.Goren@asu.edu, Arizona State University School of Music net.proselytizing (write for info): Protect your privacy; oppose Clipper. Voice concern over proposed Internet pricing schemes. Stamp out spamming. Finger ben@tux.music.asu.edu for PGP 2.3a public key.
participants (5)
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Ben Goren -
Eli Brandt -
joshua geller -
kentborg＠world.std.com -
Mike Johnson second login