substitution cipher CBC

From: Michael Scott (mike_at_computing.dcu.ie)
Date: 10/29/03 

Date: 29 Oct 2003 05:24:51 -0800

Since a block cipher is simply a substitution cipher with a much
larger block size, I was idly wondering what advantage if any would
arise from using CBC mode with a simple letter-for-letter substitution
cipher. For the XOR operation in CBC, simple addition/subtraction mod
26 could be used. Also was such a scheme ever used or suggested in
pre-computer times...

Mike Scott

Relevant Pages

  • Re: Hash of item as IV for CBC mode?
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  • Re: substitution cipher CBC
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