- cypherpunks-legacy - lists.cpunks.org

Re: DES & RC4-48 Challenges
by Andrew Loewenstern 17 Dec '03

17 Dec '03

Dan Bailey writes: > According to Biham and Shamir's Differential Cryptanalysis of DES, > "An interesting feature of the new attack is that it can be applied > with the same complexity and success probability even if the key > is frequently changed and thus the collected ciphertexts are derived > from many different keys. The attack can be carried out > incrementally, and one of the keys can be computed in real time > while it is still valid. this is particularly important in attacks > on bank authentication schemes, in which the opponent needs only > one opportunity to forge a multi-million dollar wire transfer, but > has to act quickly before the next key changeover invalidates his > message. This is the first published attack which is capable of > breaking the full DES in less than the complexity of the exhuastive > search of 2^55 keys." (7-8) > The problem with this attack, of course, is generation and > analysis of all the required chosen plaintexts. If I read this correctly, then the keys used for generation of the chosen plaintext-cyphertext pairs is irrelevant and once the required computation is done, one can crack any '...one of the keys can be cputed in real time while it is still valid.'.. So what, exactly does this mean? Can I do most, if not all of the feeding of chosen plaintext into my personal DES box in my basement, do the required computation (admittedly there is a lot of work to do here), then go out and start breaking wire-transfers with a minimal of chosen plaintext? That is what the above quotation would seem to imply. Seems incredible... I surely must be reading much more into the passage than is really there... andrew

1 0

Denning questions/reverses her position?
by Attila T. Hun 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I'm too old for this! I never thought I would see the day that Dorothy Denning would terminate her star role as a shill for the Clinton/LEA encryption ban! from: http://www.news.com/News/Item/0%2C4%2C13000%2C00.html?nd Two supporters of Clinton administration's stance on encryption released a report today finding that encryption has not inhibited law enforcement efforts, with at least one author questioning her belief in the administration's position. The authors--Dorothy Denning, a Georgetown University computer science professor, and William Baugh Jr., vice president of Science Application International Corporation-- ______________________________________________________________________ "attila" 1024/C20B6905/23 D0 FA 7F 6A 8F 60 66 BC AF AE 56 98 C0 D7 B0 -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 Comment: No safety this side of the grave. Never was; never will be iQCVAwUBM+Eh5L04kQrCC2kFAQF9wwP+INGEAnc+1akKc+dP7re8fleX4PJrmsYU UKzxgBZAsWcZC7L5WkaOygckHznOc+a37iHzDFtt3sr86DP0D/4j675qJdt/O4B+ jbxXumJ8EXmTN9bOvXK8x9JRGjR9aWzjeaJKN3X+fH4Bjbw76FR9xIFkhhNvZqnM ahBzZyL2cZ4= =MlQZ -----END PGP SIGNATURE-----

1 0

Re: e$: The Book-Entry/Certificate Distinction
by rah＠shipwright.com 17 Dec '03

17 Dec '03

At 1:06 PM 8/23/95, Timothy C. May wrote: >Whoah, there! > >I wasn't saying we were "quibbling" about definitions, I was saying that >different people have different names for things and different >interpretations, and that it behooves us to figure out what the real >definitions are, the standard names, and not invent new names when existing >names will do. Agreed. My apologies for characterizing it as "quibbling". Chain-gun Hettinga here, type first, and let God sort 'em out. A meta-reference to the problem I was talking about, I suppose. And, given what Perry said later, it's not so much a fight over definitions as I thought. >And that one benefit of class libraries for the "things" of commerce, >finance, crypto, etc., may be make it clearer what is being described. Amen. Tim, just what does "aptical" mean? ;-). Cheers, Bob ----------------- Robert Hettinga (rah(a)shipwright.com) Shipwright Development Corporation, 44 Farquhar Street, Boston, MA 02131 USA (617) 323-7923 "Reality is not optional." --Thomas Sowell >>>>Phree Phil: Email: zldf(a)clark.net http://www.netresponse.com/zldf <<<<<

1 0

Denning questions/reverses her position?
by Attila T. Hun 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I'm too old for this! I never thought I would see the day that Dorothy Denning would terminate her star role as a shill for the Clinton/LEA encryption ban! from: http://www.news.com/News/Item/0%2C4%2C13000%2C00.html?nd Two supporters of Clinton administration's stance on encryption released a report today finding that encryption has not inhibited law enforcement efforts, with at least one author questioning her belief in the administration's position. The authors--Dorothy Denning, a Georgetown University computer science professor, and William Baugh Jr., vice president of Science Application International Corporation-- ______________________________________________________________________ "attila" 1024/C20B6905/23 D0 FA 7F 6A 8F 60 66 BC AF AE 56 98 C0 D7 B0 -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 Comment: No safety this side of the grave. Never was; never will be iQCVAwUBM+Eh5L04kQrCC2kFAQF9wwP+INGEAnc+1akKc+dP7re8fleX4PJrmsYU UKzxgBZAsWcZC7L5WkaOygckHznOc+a37iHzDFtt3sr86DP0D/4j675qJdt/O4B+ jbxXumJ8EXmTN9bOvXK8x9JRGjR9aWzjeaJKN3X+fH4Bjbw76FR9xIFkhhNvZqnM ahBzZyL2cZ4= =MlQZ -----END PGP SIGNATURE-----

1 0

Government Accountability through Cryptography
by Frank Stuart 17 Dec '03

17 Dec '03

Recently, there have been many scandals (Ruby Ridge, Whitewater, the death of Vince Foster, Waco) involving the government. Even if the government is completely innocent, the perception of corruption is damaging. A big part of the problem comes from claims that incriminating documents have been hidden, destroyed, or altered. I believe I have a solution. If the government would just encrypt (using 64 bit keys or less) all their internal documents and publish them electronically, they could be checked when questions arise. The key should be held in escrow by a private company to be released only by court order, executive order, or act of Congress. Since this is very similar to the administration's proposal on cryptography, I'm sure they won't object. Perhaps we should lobby Congress. Frank Stuart | (Admiral Grace) Hopper's Law: fstuart(a)vetmed.auburn.edu | It's easier to get forgiveness than permission.

1 0

Denning questions/reverses her position?
by Attila T. Hun 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I'm too old for this! I never thought I would see the day that Dorothy Denning would terminate her star role as a shill for the Clinton/LEA encryption ban! from: http://www.news.com/News/Item/0%2C4%2C13000%2C00.html?nd Two supporters of Clinton administration's stance on encryption released a report today finding that encryption has not inhibited law enforcement efforts, with at least one author questioning her belief in the administration's position. The authors--Dorothy Denning, a Georgetown University computer science professor, and William Baugh Jr., vice president of Science Application International Corporation-- ______________________________________________________________________ "attila" 1024/C20B6905/23 D0 FA 7F 6A 8F 60 66 BC AF AE 56 98 C0 D7 B0 -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 Comment: No safety this side of the grave. Never was; never will be iQCVAwUBM+Eh5L04kQrCC2kFAQF9wwP+INGEAnc+1akKc+dP7re8fleX4PJrmsYU UKzxgBZAsWcZC7L5WkaOygckHznOc+a37iHzDFtt3sr86DP0D/4j675qJdt/O4B+ jbxXumJ8EXmTN9bOvXK8x9JRGjR9aWzjeaJKN3X+fH4Bjbw76FR9xIFkhhNvZqnM ahBzZyL2cZ4= =MlQZ -----END PGP SIGNATURE-----

1 0

Denning questions/reverses her position?
by Attila T. Hun 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I'm too old for this! I never thought I would see the day that Dorothy Denning would terminate her star role as a shill for the Clinton/LEA encryption ban! from: http://www.news.com/News/Item/0%2C4%2C13000%2C00.html?nd Two supporters of Clinton administration's stance on encryption released a report today finding that encryption has not inhibited law enforcement efforts, with at least one author questioning her belief in the administration's position. The authors--Dorothy Denning, a Georgetown University computer science professor, and William Baugh Jr., vice president of Science Application International Corporation-- ______________________________________________________________________ "attila" 1024/C20B6905/23 D0 FA 7F 6A 8F 60 66 BC AF AE 56 98 C0 D7 B0 -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 Comment: No safety this side of the grave. Never was; never will be iQCVAwUBM+Eh5L04kQrCC2kFAQF9wwP+INGEAnc+1akKc+dP7re8fleX4PJrmsYU UKzxgBZAsWcZC7L5WkaOygckHznOc+a37iHzDFtt3sr86DP0D/4j675qJdt/O4B+ jbxXumJ8EXmTN9bOvXK8x9JRGjR9aWzjeaJKN3X+fH4Bjbw76FR9xIFkhhNvZqnM ahBzZyL2cZ4= =MlQZ -----END PGP SIGNATURE-----

1 0

Australia and Encryption Policy (fwd)
by Michael Froomkin 17 Dec '03

17 Dec '03

Don't know quite how I became a Denning <--> cypherpunks conduit, but there you are; anyway this time she is passing on Orlowski's response to Ross Anderson. I have no part in this debate, honest. A. Michael Froomkin | +1 (305) 284-4285; +1 (305) 284-6506 (fax) Associate Professor of Law | mfroomki(a)umiami.ir.miami.edu U. Miami School of Law | P.O. Box 248087 | It's hot here. And humid. Coral Gables, FL 33124 USA | See (experimentally & erratically) http://viper.law.miami.edu/~mfroomki ---------- Forwarded message ---------- Date: Wed, 23 Aug 1995 15:29:17 -0400 (EDT) From: Dorothy Denning <denning(a)cs.cosc.georgetown.edu> To: MFROOMKI(a)umiami.ir.miami.edu Cc: denning(a)cs.cosc.georgetown.edu Subject: Australia and Encryption Policy ----- Begin Included Message -----

1 0

Denning questions/reverses her position?
by Attila T. Hun 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- I'm too old for this! I never thought I would see the day that Dorothy Denning would terminate her star role as a shill for the Clinton/LEA encryption ban! from: http://www.news.com/News/Item/0%2C4%2C13000%2C00.html?nd Two supporters of Clinton administration's stance on encryption released a report today finding that encryption has not inhibited law enforcement efforts, with at least one author questioning her belief in the administration's position. The authors--Dorothy Denning, a Georgetown University computer science professor, and William Baugh Jr., vice president of Science Application International Corporation-- ______________________________________________________________________ "attila" 1024/C20B6905/23 D0 FA 7F 6A 8F 60 66 BC AF AE 56 98 C0 D7 B0 -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: latin1 Comment: No safety this side of the grave. Never was; never will be iQCVAwUBM+Eh5L04kQrCC2kFAQF9wwP+INGEAnc+1akKc+dP7re8fleX4PJrmsYU UKzxgBZAsWcZC7L5WkaOygckHznOc+a37iHzDFtt3sr86DP0D/4j675qJdt/O4B+ jbxXumJ8EXmTN9bOvXK8x9JRGjR9aWzjeaJKN3X+fH4Bjbw76FR9xIFkhhNvZqnM ahBzZyL2cZ4= =MlQZ -----END PGP SIGNATURE-----

1 0

RUB_han
by John Young 17 Dec '03

17 Dec '03

Hurray for PRZ and D.FR and the yet-untargeted DCF unconspiratorily, merrily, incites. Now, sordid lucre biz: 8-17-95. NYPaper: "A mystery bankers love: How do credit cards stay so profitable?" The profit on credit card operations is almost five times the overall profit rate in banking. Last year, eight of the top nine commercial banks ranked by return on assets specialized in credit card loans. In a free market, this isn't supposed to happen. If the business is immensely profitable -- and that profitability is no secret -- why hasn't wideopen competition forced banks, at best, to offer lower interest rates to consumers or, at worst, at least to dissipate their excess profits in ever greater spending for promotion? This is not a pretty picture of free markets at work. "Mastercard Joins Banks to Plan Card That Works Like Cash." [This amplifies a bit the anonymous post on SmartCash.] The venture, called Smartcash, plans to issue what are called "stored value" or "electronic purse" cards. Customers would be able to load money onto these cards, say $20 or $50, at automated teller machines or by calling their banks with specially equipped telephones. "We're in a state of chaos," said Stephan Seidman, the editor of Smart Card Monthly, a trade publication. "A year ago banks said there was no good reason to issue smart cards. Now they are in a headlong plunge to get something out fast." The result, he said, is shifting and competing alliances that may lead to incompatible systems and confusion for consumers. Deux: RUB_han (about 10kb)

2 1