On Mon, 13 Feb 2006 18:16:20 EST, Wirt Atmar <[log in to unmask]> wrote:

> ...by far the easiest thing to do is to use an XOR encryption
> procedure...
>
> If you adopt this algorithm, all you need do is never let anyone
> know the encrypting string. If you don't share that string, it's
> a pretty tough little procedure to defeat -- so long as you don't
> use a common phrase to encrypt your data with. 

There are some important caveats.  The most important is that the 
key length be comparatively large with respect to the size of the 
target data, 100% is ideal, > 50% desirable, < 30% problematic, < 
10% weak; and that you only ever use a given key exactly once. 
These are the essential characteristics of the one-time-pad 
encryption method.  The critical problem of encryption is non-
compromised key transfer between origin and destination, which is 
what public key encryption systems are all about.

Regards,
Jim


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