Re: Composing large block cipher from smaller ones



On Mar 4, 9:45 am, biject <biject.b...@xxxxxxxxx> wrote:
binary bwts or unbwts you pick with extra key bits or fix the pattern
of bwts unbwts
followed by the 8bit cypher pass with new key bits.

The problem with that scheme is there are weak keys consider the key
byte 10101010 or 11110000 or 00001111 or 01010101, etc.... they're all
identity functions.

Generally, it's undesirable for a cipher element to change the size of
the message in an unpredictable fashion. That's usually left to the
codec stage.

Tom
.