Re: Basic tools of encryption: Transposition and substitution?
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Re: Basic tools of encryption: Transposition and substitution?

From: Peter Fairbrother <zenadsl6186@zen.co.uk>
Date: Tue Jan 03 2006 - 01:22:16 CET



Unruh wrote:



> Phil Carmody <thefatphil_demunged@yahoo.co.uk> writes:


> 


>> Doug <doug@null.com> writes:


>>> Peter Fairbrother wrote:


>>> 


>>>> In lossless substitution the entropy remains unchanged. In lossless


>>>> compression the entropy also remains unchanged - no entropy is lost - the


>>>> message space shrinks.


> 


> In general the message expands. It is only for messages with a lot of


> repetitions that the message space shrinks.



Aargh, I thought that would come back and bite me. I meant to say the


message size, not space.



Nope, what I mean is: I should have said "size, not "space". I hope I've


got that right now.



That"s what I meant. If I didn't get it wrong again. This computer is


playing "Communication Breakdown" at high volume.



Oh babe, I'm gonna leave you ..


Received on Tue Jan  3 03:42:47 2006