Re: normal?

Charles E. Novitski (c.novitski@cmich.edu)
Tue, 10 Jun 1997 01:58:39 -0400 (EDT)


>On Sun, 8 Jun 1997, Justin Dolske wrote:
>
>> On Sun, 8 Jun 1997, Jason Buchanan wrote:
>[..]
>> > However, the 4th machine i'm running it on is a SS2 and it said "Key
>> > found" or something like that... and since I wasn't paying close attention
>> > I don't know if this is normal for the sun build to display this or not.
>>
>> I havn't seen an excited message from Rocke, so I'll assume you simply
>> misread the screen. :-)
>
>Here's what it would say (and more):
>
>(excerpt of a 'strings' on the Linux i486 binary of deschall client)
>
>[..unreadable stuff snipped..]
>AAAAAAAAAAAAAAAA
>5555555555555555
>2^21 complementary pairs of keys tested: %ld seconds
>select
>sendto
>recvfrom
>Received packet from host %lX
>Key was found, but network notification failed.
>Please send e-mail or telephone!!!!!
>Unable to contact server for more work.
>DES Challenge Solver
>Copyright (c) Rocke Verser, 1986, 1997
>All Rights Reserved.
>***** FOR USE IN THE USA AND CANADA ONLY *****

1. Does anyone have convincing evidence that this "key not found" report
(above) is just a misaprehension, rather than a real result that didn't get
sent back to the server? If not, is it not worth (and/or possible)
rechecking the keys sent to that site?

2. Could you explain the rationale in choosing keys? Is is true that keys
are chosen at random, with duplications not being guarded against? If so,
why not have a check against duplication? Can it be proved mathematically
that it requires too much computing power (relative to key breaking) to be
attractive?

3. What is the reason for lack of cooperation between groups (Solnet,
SGI)? If the keyspace were divided up between the competing groups, then
their respective chances of being the winner would not be altered. But the
success of the combined groups would be accelerated. And if they key
weren't found when all space were checked because certain competing clients
were defective, the Deschall group could redo the other group's space as
needed. In my naivity, I don't see the downside. Is it that there has to
be gaming decisions related to the psychology of possible choice of keys
(not being even, being large, etc.)

Charles