🚀 go-pugleaf

lwloen@rchland.vnet.ibm.com (Larry Loen) writes:
> In the hypothetical example, compression moves the overall cost up
> to 2 to the 60 from the original 2 to the 54.  That ain't chicken
> feed, but it will probably not make a serious difference in overall
> security, in the end.  If one can exhaustively break DES in a day,
> having to wait 64 days will defeat some opponents, but others will be
> just as happy on the 64th day as the first. 
> 
> Note, however, that the key technology remains breaking the basic DES.  Once
> one can spring for a cost on the order of 2 to the 54th, it does not seem
> like the typical opponent will run out of money at 2 to the 60th or that they
> will not simply wait the extra time if they do.

Does it change the analysis if I substitute "month" for "day" above?
"If one can exhaustively break DES in a month, having to wait a little
over 5 years will defeat some opponents..."

I have to imagine that it would defeat nearly all the opponents, since
most of the data will be well-nigh worthless after 5 years.  Along the
same lines, even governments can't necessarily spend 64X to complete
a job which would otherwise require an expenditure of X.

In short, linear increases in complexity with sufficiently large
constant factors may provide a better security enhancement than do
exponential increases with small constant factors.

Not a flame, just a nit.

Lyle		Transarc		707 Grant Street
412 338 4474	The Gulf Tower		Pittsburgh 15219
"I don't believe it!  I believe it, though..." 	- kazar