Re: How fast computers have made ciphers unbreakable

From: Mxsmanic (
Date: 11/11/04

Date: Thu, 11 Nov 2004 10:55:56 +0100

Martin Bodenstedt writes:

> How sure can we be of this?

We can never be sure that no one has found some unpublished way in which
to compromise a cipher that vastly diminishes the cost of an attack.

However, we can say with confidence that there are no publicly-known
ways to crack a cipher with less than some specified amount of

> How sure can we all be that the algorithms in use today do not contain
> either a backdoor or an inherent weakness that can be exploited without
> having to resort to brute force?

We can't. But since that will never change, it makes sense to forget
about it and just work with what we do know. Perhaps cipher A has been
massively compromised by some spook agency, but what if it has? The
only option is to switch to cipher B, but you don't know if cipher B has
been similarly compromised, so it really doesn't matter. Ultimately you
can only go by what you know. Change ciphers if you hear of a dangerous
compromise, otherwise don't worry.

Transpose hotmail and mxsmanic in my e-mail address to reach me directly.

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