Re: Double Encryption Illegal?

In article <jgfunj-1609002156160001_at_dial-245-138.itexas.net>, wtshaw <jgfunj_at_vgrknf.arg> wrote:  

> In article <39C3966A.67A0A5DC_at_t-online.de>, Mok-Kong Shen
> <mok-kong.shen_at_t-online.de> wrote:
> ...

>> You meant it should be triple, like 3-DES??
>> 
>> M. K. Shen

FYI: 3-DES consists of three rounds of DES, using two or three different keys.  

> An algorithm can be made of any conbination of steps. When two or more
> pieces are combined, the result is one piece. Consider that such a
> request, regulation, standard, whim, or pipe dream to limit so called
> double encryption is a fog to confuse whereever possible; ambiguity shows
> dualism of purpose.
 

Nonsense! Calling the use of two encryptions in succession "double encryption", or three encryptions in succession "triple encryption" is a correct description of the procedure.  

However, "double enryption" or "triple encryption" is not always more secure than "single encryption". Consider for instance the good ol' Caesar cipher: double-Caesar or triple-Caesar will be no more secure than single-Caesar. But triple-DES will be more secure than single-DES.  

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