[RC5] Dupes (fwd)

Peter A. DeNitto denitto at llamas.net
Fri Apr 10 15:16:18 EDT 1998

Let me point out here....

The Master IGNORES all dupes.

It drops them to a log file that I go through.  

Dupes will NOT increase your stats.

People have been asking if 10-15% are dupes.  No.  The master does not
hand out keys that have been checked.  The master will hand out keys that
have been issued before but have not been returned as checked. (So named
"Tardy" keys.)

The RC5-64 keyspace consists of 256 2^56 blocks of space.
Because of space constraints, the master server's puny hard drive can only
hold 4 active 2^56 blocks.  We were approaching the end of issuing our 4th
full block. It was decided to re-issue keys that had not been checked but
had been  issued from the first block that was handed out, to close it out
and get a fresh 5th block of keys to distribute. These keys were issued
over 120 days ago.  

In all honesty, any machine other than truly offline machines should be
set to flush daily.  More often if possible.  In the future we will try to
notify in advance when a block is being "closed out".  During that time
you would need to flush more often to keep the chance that if you are
issued a "tardy" block, that you can return it before it is reissued again
because you haven't returned it.

Here's an example... (hypothetical)

Block 0xABCDEFE5A0000000 was issued on day 2 of the contest... 
The machine it was issued to hard drive crashed and the block was never
Day 20 we issue all of the 0xAB space, move on to 0xAC.
Day 160 comes around, and we need to get 0xAB off the master (close out)
	because of lack of Drive space on the Master's Hard Drive.
.. Block 0xABCDEFE5A0000000 gets issued to your machine.  
.. Your machine gets 1000 blocks during that time.
.. Block 0xAB is finished it's Reissue.
... Tardy keys are reissued again.
... Your machine hasn't returned 0xAB yet.
... Block 0xABCDEFE5A0000000 is reissued to Me.
... My machine gets 10 blocks.
... I return Block 0xABCDEFE5A0000000 in 15 hours.
... Block 0xABCDEFE5A0000000 is marked complete.
Day 161 0xAB is 100% finished and is removed from the master.
Day 162 comes around, your 1000 block buffer flushes.
.. All your 0xAB blocks are marked duplicates because the block has
already been completed.

This goes DOUBLY for the DES contests.  A time based contest (like DES)
relies on a quick fetch/flush turn around.  

This does not diminish the fact that you should update your client when a
new one is built.  7002 clients were known to be bad and a 7003 build was
issued that same day.  Please upgrade those.  

Donations of hard drive's and all will help alot.

So, as an action:
	Set your RC5 Buffers so that your machine fetches/flushes once a
	Set your DES Buffers so it will fetch/flush 4-6 times a day.
	UPGRADE YOUR PERSONAL PROXIES. (No one should be running a 95/NT
					based proxy anymore)
	Check in on #distributed on EFnet IRC for questions, or send email
		to rc5help at distributed.net.


Help Crack Government Encryption - Join the Bovine Project: www.distributed.net
The cows are tromping all over America. Cows can replicate. They're
being born all over the world. There's plenty of beef available!
		-- US Representative Zoe Lofgren (D-Ca)

---------- Forwarded message ----------
Date: Thu, 9 Apr 1998 12:22:57 -0400 (EDT)
From: "Peter A. DeNitto" <denitto at llamas.net>
To: rc5 at llamas.net
Subject: Dupes

Well, people have been doing alot of duping this past week...
And 95% of 'em are done w/o the knowledge of the people doing them, it's
because they're running old clients or old proxies...etc. 

I'll just detail Yesterday (0407)

792706 Total duplicates yesterday.

Version #	Dupes	%
7018		4	0%
7017		24489	3%
7016		57755	7%
7015		116	0%
7014		17794	2%
7013		57016	7%
7012		5283	0%
7011		61729	7%
7010		22800	2%
7009		27618	3%
7008		6737	0%
7007		2016	0%
7006		24444	3%
7005		1193	0%
7004		71	0%
7003		909	0%
7002		295007	37%
7001		19991	2%
6404		22238	2%
6403		58248	7%
6402		21384	2%
6401		65772	8%

58% of all dupes are done by old clients.

I hope this tells everyone that there are reasons and benefits to
upgrading ^_-

ALSO:  Make sure your PERSONAL PROXY is running the latest version, which
is 277 (275 on irix).  

Following are the top 10 dupers.

#1: 267501 blocks spammed by andreas at FreeBSD.ORG.
	Andreas is running a 7002 client.
#2: 48159 blocks spammed by yshige at pluto.dti.ne.jp.
	yshige is running a 6401 client.
#3: 37767 blocks spammed by genie at cc.nccu.edu.tw.
	genie is running 7013
#4: 29319 blocks spammed by toshi at ottot.to.
	Toshi is running a variety of client versions.  Looks like it's a
#5: 26784 blocks spammed by guido at informatik.rwth-aachen.de.
#6: 24528 blocks spammed by tomo at onbiz.net.
	Running 6403
#7: 21864 blocks spammed by delznic at acm.org.
	Delznic is running 7002
#8: 12563 blocks spammed by rc5 at celab21.pc.elec.uq.edu.au.
	Running 6401, thru a proxy perhaps.
#9: 11968 blocks spammed by chris at squirrel.com.au.
#10: 7271 blocks spammed by wdavid at osni.com.
	Running a variety thru a proxy it sems.


Help Crack Government Encryption - Join the Bovine Project: www.distributed.net
The cows are tromping all over America. Cows can replicate. They're
being born all over the world. There's plenty of beef available!
		-- US Representative Zoe Lofgren (D-Ca)

To unsubscribe, send 'unsubscribe rc5' to majordomo at lists.distributed.net
rc5-digest subscribers replace rc5 with rc5-digest

More information about the rc5 mailing list