Re: Stream cipher against block cipher

From: Mok-Kong Shen (mok-kong.shen_at_t-online.de)
Date: 06/29/03 

Date: Sun, 29 Jun 2003 12:20:35 +0200

AE wrote:
>
[snip]
> It is easy to convert a block cipher to a stream cipher (use an
> appropriate mode of operation and you've got a cipher as strong as the
> initial codebook) while it is hard to convert a stream cipher to a block
> cipher (one can do it your way but dependent of the type of stream
> cipher one is using the result is either severely flawed or completely
> broken).

While one is on the issue of one type of cipher vs
another, I just want to say that it might be practically
sensible to leave open the posssibility of appropriately
combining stream cipher techniques and block cipher
techniques in one design, thus eventually reaping the
benefits from both subfields of crypto methodology.

M. K. Shen

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