Re: Is two times encrypting ALWAYS more secure than one time encrypting ???

Date: 05/09/02

Date: 9 May 2002 19:35:19 GMT

Barry Margolin <> wrote:
> In article <abeblu$irc$>, <> wrote:
>>In Sven Fischer <> wrote:
>>> A question concerning the security of encrypting. Assume we have two different
>>> encryption tools.
>>> Does it improve the security (uncrackability) of the starting text if I encrypt
>>> this text with one tool and than afterwards with another ?
>>No, not really.
>>If one is using secure encryption, one run is enough.

> What about things like Triple-DES -- isn't that essentially running the
> text through DES encryption three times? If multiple encryptions doesn't
> buy you anything, why do this?

It does so while extending key length to 112 bits. The point is
the longer key, not that DES is used several times.

> P.S. Wouldn't this discussion really be more appropriate for sci.crypt?

> --
> Barry Margolin,
> Genuity, Woburn, MA
> *** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.
> Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.

Peter Håkanson         
        IPSec  Sverige      ( At Gothenburg Riverside )
           Sorry about my e-mail address, but i'm trying to keep spam out,
	   remove "icke-reklam" if you feel for mailing me. Thanx.