[387] in Kerberos
faster encrypted rlogin
daemon@TELECOM.MIT.EDU (Mark Lillibridge)
Sun Jun 5 17:52:10 1988
From: Mark Lillibridge <chariot@ATHENA.MIT.EDU>
To: raeburn@ATHENA.MIT.EDU
Cc: kerberos@ATHENA.MIT.EDU
In-Reply-To: Ken Raeburn's message of Sun, 5 Jun 88 16:21:42 EDT <8806052021.AA27194@BINKLEY.MIT.EDU>
Reply-To: chariot@ATHENA.MIT.EDU
Well, the scheme you describe for generating random numbers is
quite close to one of the schemes used in cryptography to generate
poly-perfect random number generators. (A poly-perfect random number
generator is a generator who's output is indistishable from a truely
random sequence in polynomial time) The difference is that cryptography
replaces the DES function with a number theory function (RSA for example
although it is slower than some alternates) that we have reason to
believe is not invertable in polynomial time. It can be proved that if
the function used is indeed not invertable in polynomial time, then a
poly-perfect random number generator will result.
Unfortunely, since very little is known about DES mathamatically
at the moment, it is very hard to say if it is not invertable in
polynomial time. None the less, I think that this method is reasonably
secure compared to the original method. Anyone with the resources to
break this method is almost certain to be able to break the original
method as well. This is only my opinion of course, through....
- Mark Lillibridge
