Re: Dynamic password authentication scheme

[Erich Buri <buri () z17 net>]

I agree that it would be great to have somthing like dynamic passwords.

but i think that your solution does not change much.

> in which the password is not stored in the hard disk or any auxiliary 
 > memory and gets changed every time a user is going to be
> authenticated.

but isn't there this values computed from the random input that gets 
stored on the server? This is much like the password. Because if i know 
this value and the time I wan't to do the login, i can calculate the 
password!

Same thing if i steal the secret value from the customer 
(sniffing/reading on the disk, since he may store it there.../keyloggin 
the value when it is typed into the algorithem to compute the 
one-time-password. since this function must be one-way and is thus very 
likely complicated).


Did i miss the point?

Apart from that there exists already a solution called SecureID.

http://www.hpcmo.hpc.mil/Htdocs/SECURITY/securid_q.html

which does basicly the same thing except that in this case the secret 
value is stored inside the card and the one-time-password is calculated 
directly by the card.

Tell me if i'm wrong but i think your solution is basicly shifting the 
problem from cracking the password to stealing a number.

gruss
buri

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