December 2003 - cypherpunks-legacy

Remailer-list pinging frequency
by usura＠vox.hacktic.nl 17 Dec '03

17 Dec '03

raph(a)kiwi.CS.Berkeley.EDU (Raph Levien) writes: : 1. Encrypt the ping, so it looks like so much PGP traffic. A good idea, if a c'punk remailer cannot decrypt a message it should be considerd "down". : 2. Pad it with a random amount of junk (but not _too_ much :-), so : traffic analysis based on size will fail. That would be the start of RemailerNet. :) : 3. Chain it through other remailers. A good approach might be to : choose two random remailers out of the "top five," and sandwich rebma : between them. The drawback is that it penalizes rebma for their : latency and failure rate, but this might be acceptable. One question about your "suggested path", it looks like you thake the tree fastes remailers [if using kiwi.cs.berkeley.edu] If the two remailers from Hal Finney are consecutive [ie. 1 and 2 fastes] a suggestion to mail from alumi to portal would IMHO be wrong, because for security reasons both remailers should be regarded the same, since they are operated by the same person. [same goes ofcourse for the usura(a)hacktic.nl and the vox.hacktic.nl remailers wich are operated by me] -- Exit! Stage Left. Alex de Joode <usura(a)vox.hacktic.nl>

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Re: Remailer-list pinging frequency
by Pierre Uszynski 17 Dec '03

17 Dec '03

Raph Levien (raph(a)kiwi.cs.berkeley.edu) says: > I believe that I am providing a useful service with my remailer > list, but I have received one complaint about the frequency of > pinging. If I may suggest without implementing :-) use adaptive pinging. There is little point in sending one ping per hour while getting no answer, then getting 24 answers all at once, and then doing the same thing all over again the next day... A more general way to put this is that pinging much more frequently than necessary does not give any more info. If you measure up time and latency both in days, there is no need to ping more than once a day. If you measure up time and latency respectively in days and minutes, there is still no need for very frequent pinging. The only case where you need frequent pinging is when a site keeps going up and down and you want to distinguish latency due to down periods from operating latency.... But from a practical standpoint, these need not really be distinguished. Most mailers are configured correctly to retry failing connections, so that connections that are down only for a few hours are seen only as long latency. In conclusion: Start with pings at random phase, and 180 minute period. If for the last 16 pings of average period n minutes (random phase), the average latency is more than 4xn minutes, triple the period. Use a maximum period of once a day. If the average latency is less than n minutes, divide by three the period. Use a minimum period of one hour. You could do the same thing for very stable sites (stable latency): they require less pinging. Short latency stable sites need not be pinged every hour. The rule may have to be fixed a bit one way or the other, but it would help both your pinging script and slow remote sites (personal remailers) by cutting traffic for both. Pierre. pierre(a)shell.portal.com Still, there is no harm in making pinging traffic look more like real traffic. Like you said chaining is questionable for pinging (and if it comes from a remailer site, and goes back to a remailer site, it would not be obvious if it still met 1, 2 and 4): > 1. Encrypt the ping, so it looks like so much PGP traffic. > > 2. Pad it with a random amount of junk (but not _too_ much :-), so > traffic analysis based on size will fail. > > 3. Chain it through other remailers. A good approach might be to > choose two random remailers out of the "top five," and sandwich rebma > between them. The drawback is that it penalizes rebma for their > latency and failure rate, but this might be acceptable. > > 4. Randomize the time that the ping is sent.

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Re: Anonymous questionnaires
by jim＠bilbo.suite.com 17 Dec '03

17 Dec '03

Lucky Green asks how to: 1. Correlate my answers to the answers of my partner. 2. Verify that I have indeed sent in a filled out questionnaire (and send me a check for participating). 3. Allow a supervisory agency, such as the U.S. Department of Health and Human Services, to verify that the researchers did not just make up all the data - that is to allow an audit. 4. Protect my privacy by making it impossible to correlate my name to the answers given. The following a complicated and impractical solution (but it was a fun exercise): First, assume everybody participating in the study is on the Net and is crypto savvy. :-) Each participant generates a new public-key pair for the study. The supervisory agency generates a new public-key pair and gives a copy of the public key to each participant. They do not give a copy to the researchers. The researchers generate a new public-key pair and give a copy of the public key to the supervisory agency and each participant. Finally, each participant generates a symmetric key, blinds it, and has the supervisory agency sign the blinded symmetric key. Ok, assume Bob and Alice are a couple participating in the study. Bob and Alice each get a copy of the questionaire, the researcher's public key, and the supervisory agencies' public key. They each generate and blind a symmetric key and have it signed by the supervisory agency. Bob fills in his copy of the questionaire and then signs an MD5 hash of his completed questionaire. Alice does the same. Bob gives his signed hash value to Alice and Alice gives her signed hash value to Bob. Bob appends Alice's signed hash value to the end of his completed questionaire. Alice appends Bob's signed hash value to the end of her completed questionaire. Neither sees the other's completed questionaire. Bob now signs his questionaire with his private key. Alice signs her questionaire with her private key. Bob encrypts his (now signed) questionaire and his public key with his symmetric key. He next encrypts the signed (and now unblinded) symmetric key with the supervisory agencies' public key. Finally, he encrypts those items, along with a cleartext copy of the completed and signed questionaire, with the researcher's public key and e-mails the result to the researchers using a chain of anonymous remailers. :-) Alice does the same. Ok, the researches receive an anonymous e-mail message from somebody (call him Ted) that is encrypted with their public key generated specifically for this study. They decrypt the message and get four items: Ted's completed and signed questionaire, Ted's encrypted and signed questionaire, Ted's encrypted public key, and Ted's encrypted and signed symmetric key. Since Ted's public key is encrypted with his symmetric key and the symmetric key is encrypted with the agencies' public key, the researchers cannot read these items. Also they cannot verify the signature on the cleartext copy of the questionaire. However, they check that everything appears to conform to the requirements of the test, so they credit Ted with completing the questionaire and e-mail him (via the encrypted reply block) an IOU signed by the researcher's private key. More on the IOU later. The researchers collect all the anonymous replies and send them as a group to the supervisory agency. The supervisory agency decrypts all the encrypted symmetric keys using its private key, validates the signatures on those keys, then uses the symmetric keys to decrypt the participants' public keys and encrypted questionaires. Since the symmetric keys were blinded when the supervisory agency signed them, the agency does not have enough information to be able to determine which participant completed which questionaire. All the agency can do is verify that the questionaires were completed by people who had symmetric keys signed by the agency. Since the questionaires where e-mailed to the researchers via anonymous remailers, the researchers can't collude with the supervisory agency to determine who complete which questionaire. The agency sends the decrypted public keys and questionaires back to the researchers. The purpose of the signed symmetric keys was to help prove to the agency that the researchers did not fabricate the study results. This is not perfect, the researchers could have pretended to be all of the participants and could have filled out all of the questionaires. However, if they did that, they would be unable to produce any real participants, if they were ever challenged. The researchers use the decrypted public keys and the signed MD5 hashes to group the questionaires into related pairs. The researches can compare the decrypted questionaires sent back from the agency with the plaintext copies received from the participants to verify that the supervisory agency did not substitute any of the real questionaires with bogus ones. The researchers can now analyze the questionaire data, but they don't know which participant filled out which questionaire. However, the researchers do know which questionaire is paired with which other questionaire. More on the IUO: How does a participant redeem the IUO without revealing information which could allow the researchers or the supervisory agency to pair them up with their completed questionaire? Well, the IUO is really a blinded message sent to the researchers in the anonymous message along with the other stuff. If the researches are satisfied with the plaintext questionaire, they will sign the blinded IUO and send it back via the encrypted reply block. The participant unblinds the signed IUO. The participant can now redeem the IOU offline without giving anyone any information other than the fact the person was a participant in the study. Of course, if there was real anonymous digital cash, there would be no need to use an IOU. How to prevent a totally fabricated study: As mentioned above, the researchers could fabricate the entire study by pretending to be all of the participants, getting known symmetric keys signed and so forth. How can the supervisory agency determine the difference between a real anonymous participant and a bogus anonymous participant? It is at this point that we have to step out of cyberspace and back into the real world. Ideally, the supervisory agency needs to determine two things: 1) All of the participants were real people. 2) None of the participants colluded with the researchers. Requirement 1 can be satisfied by having the supervisory agency redeem the IOUs using money they escrowed on behalf of the researchers. When the participant comes in to redeem the IOU (or snail mails it in), the supervisory agency can check the ID (driver's license, SS#, whatever) of the participant, verify the signature on the IOU, and hand over (or mail) the check. The signed IOU will not give the agency the ability to determine which questionaire the participant filled out. I know of no way to enforce requirement 2 without violating the anonymity of the participants. The researchers could hire a bunch of people to redeem bogus (but correctly signed) IOUs, fooling the supervisory agency. The only way I can think of to prevent participant/researcher collusion is to have independent auditors standing over the participants while they fill out the questionaires. Not what Lucky Green had in mind, I'm sure. So anyways, there it is, a complex and impractical solution that still doesn't solve all the problems. Oh well. Time to go back and work at my real job. Jim_Miller(a)suite.com

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U & Pu "poisoning of the environment"
by Brad Dolan 17 Dec '03

17 Dec '03

>From: IN%"usura(a)vox.hacktic.nl" >To: IN%"cypherpunks(a)toad.com" >CC: >Subj: RE: Nuclear Weapons Material [discussion about basement bomb building deleted] >One doesnot need to detonate the Uranium/Plutonium one can poison the >watersuplies and make havoc with The Simple Bear Necessities of life. >-- >Exit! Stage Left. >Alex de Joode <usura(a)vox.hacktic.nl> Well, I wouldn't want to snort the stuff daily, but its toxicity has been overrated in the popular press. Epidemiologic studies of workers [even wartime workers with impressive body burdens/ exposures] in a number of uranium bomb-making centers have found ~ no health effects. I haven't heard much about Pu-workers. Groeten, bdolan(a)well.sf.ca.us

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Re: Voluntary Governments?
by elton＠sybase.com 17 Dec '03

17 Dec '03

Right ... I had taken this offline, but it looks as though it ain't quite dead yet. Kindly stop reading now if you wish this subject would go away. Consolidating two messages from Jim Dixon: >Jason's use of the term 'tax' in a special sense is no more an abuse >of the language than the attempt to change the conventional meaning >of the word 'government'. and >You can't simply take over the ownership of words in the English >language. 'Government' is indeed the name used for an entity that >exercises authority or enforces laws. Of course we can -- it happens all the time. However, this time I haven't usurped the meaning of anything. Force -- the threat or actual use of violence -- is the essence of government. You just said so yourself: "enforces laws". Here's the closest applicable dictionary definition of "government", taken from the Random House Dictionary of the English Language: "1. the political direction and control exercised over the actions of the members, citizens, or inhabitants of communities, societies, and states; direction of the affairs of a state, community, etc.; political administration." This is amplified by looking at "govern" in the same dictionary: "1. to rule by right of authority, as a sovereign does." "Rule", or "political ... control" are only ever exercised through force. People keep using that word, "enforce", without looking carefully at it. >From the same dictionary: "to put or keep in force; compel obedience to." "Enforcement", regardless of the dry dictionary definition, is the essence of government. Without the power to enforce arbitrary rules, there can be no government. There are several methods of achieving compliance with a set of rules: social pressure (shunning, as some religious sects do); withholding of goods or services (the degree that Jason spoke about being denied); and topical application of violence ("enforcement"). Of these, the first two are related, and are commonly practiced by social units that don't recognize the right to use force on one another. The last named is the only one that results in physical damage to the person being "ruled", and is also the only one that can physically prevent that person from engaging in the proscribed behavior. The others can make life bloody unpleasant, but they won't terminate it. One other thing: >I grew up in a small town of 5,000. It had a city government. The >county government was in the same town. No one denies that California >has a government, I think. And then there was the US government. And >we had city police, the sheriff's office, the Highway Patrol, and the >FBI paid an occasional visit. Uh ... you _do_ understand that that's a specious argument, yes? What do you suppose the outcome would be if your home town were to legalize marijuana, and then attempted to prevent the DEA from enforcing the overriding federal law? Yes, we have a distributed government, with each layer operating under the authority of the next layer up; but each layer can only add restrictions, never remove them, and each enforces its restrictions by the same method as the layers above it: main force. Further, each attempts to prevent other agencies from enforcing sets of rules counter to the ones they themselves enforce. That's what makes them true "governments", rather than some other social institution. Here, someone will surely object that by this definition, the Mafia can be considered a government. Well, if they can successfully kick the existing thugs off of some plot of ground, and then defend it against all comers, then yes: that's exactly what they'll be. How else do you suppose that governments become established? -- Elton

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Message for 0x7CF5048D
by Random Factor 17 Dec '03

17 Dec '03

sorry to inflict this on everyone. i've redirected followup elsewhere. randy -----BEGIN PGP MESSAGE----- Version: 2.6 hIwCDYaeGXz1BI0BBACzJWMo49PMXrCnV5SLci/MqoUmldyAPY3WCyhOC/PYB++X Bpb+zOqs3kTJpaT0f9hwpiLHpB96lPkxjFHAP9k+lgekjGpMcICB/6xBjp8S1D0q L7wmiwZ933HUEorPrPOIlVJ/7Ufv8Y1uJbTZR7CTDoYlU4IP3Y/IE8/tWoIghKYA AAQw9t6doZJceiZVYBkY3TwgH1pTZdfvDTTssyucqkp6A09ClKpEgzzfKZnAXYZ8 c/QXd8thWqcLBERx4aPXfcW09w8knO6DUZgkk3pFHmdGshp3/gcTaO/ko8ecbI7V OnzPn5hjONWRYGuYB9praK5Fe/j//UVjTlaY3Tb5QY1lK+GSLFU7ktiuMXqagQYK 72mN8wpCZZlh1eGThu89UwsGjfiqFzvpmJTWa9+U1VtX+DNXlOYkcC5K5gqmDb97 XuDNakLX79O4wjeBJVx5xOglqEHS+wnt09EwG+IuwLxgPPVKpnm0qhAJNyt8Syhj XLiAaqlShOQIaXNp/qWKGrrIMcDvzBBI/2LlXHJZ/h5Ykl/c4/+FeqYOx26uMbCk SiI4LRsvwFE9cR/jlgPyzGRVsLB6WagUN8uhLXkxQKwMNlDSU5ZFOQSOZ2HuYwZc EgDQwtSXEgFBNgCKGhogQ2SyEj0GnH2bDLPxiGgM1svL1VzwogvgV6mS0wLed56V qT8pXdCSzY7LJCvVJ2kmnsqMl5y9E1wmqujeBQdIhr/SqJ2W4PXTgHiyYxKUvOWK 6SJdxMxCWdO8Vhr9oqpERSn0RuC2wsroNiposGaIvtzha5P975QmNZJDzupcCtmQ T8bXvK9loVfuKxtxgH2rc8IFjHPWhqrIkvUaq6mOUajIiY+DKzT1X6+Pus7RKnl+ EMdavCLY8tynKzkiHobPK5eUSo9XrwYMfaMCibAS+2DXFD83CDK7AoUfRnLA73ID xHb6TRw3ocHfKRyk8n+mwj6VEGN4RQIy1rgAtildynQCJC3H7qW6CAJQ/kfojBLf Cu+Au8GiPyGR8u3m2tgZgI4sqibOn5Xd5q5Ju4OiTYWZiXuQFjHiDUfTCQLojjf0 F8x33jl+c3jjyNM+L4xBs8mqXOFyvGaeQY1IyrAMYddVWHXU/NwJk/S73UBCXAaz i3r16GH7QsQ2GQiNvjqitkZOnP7rRgn2DExXnN2WrMbQID8kCV5WU8kGlKkdhPUK KxrpL6dJ49gPVOSxvRwWXujXaWvpKGtwBQ9sk6fVvhqilmA3TtSJ0u+vpPIWzSJ7 idML1PW5UG+E4j5lJpvZAwUEB9DRs54b1zlZ2kThDlic4R9N5akHvih8dimT/iFK qXxHt7nsExCW5kX0HFJVxj+4iEw77w7W9evo+M7JJW9ZWcNxk8P1SoYpD8I57b0c OUv+znOMbYcZqex2UuO0BworlIf+hEjS1spgUU8YlWvJaqRt7vQ0iXkGvebhYmTT BPM8AiPrJpQzoBEwBdDZ6ytWkbBTjb9UpDH/KFHPB+T1hRzB1DYuwI6nodIwh4aW zsWBahfhVtxZwRAHoC+ii70wedl28nwz+mAdBFvNl4Lh9WjYtE8x9pue2iCmWTuY X5Ts8zreyBD9a87/NbPcqucuhQ== =R4uo -----END PGP MESSAGE-----

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RE: U & Pu "poisoning of the environment"
by merriman＠metronet.com 17 Dec '03

17 Dec '03

>Well, I wouldn't want to snort the stuff daily, but its toxicity >has been overrated in the popular press. > >Epidemiologic studies of workers [even wartime workers with impressive >body burdens/ exposures] in a number of uranium bomb-making centers have >found ~ no health effects. > >I haven't heard much about Pu-workers. Well, there you go - that's your answer. :-| - - - - - - - - - - - - - - - - - - - - - - - - - - Finger merriman(a)metronet.com for PGP/RIPEM public keys and fingerprints. Unencrypted Email may be ignored without notice to sender. PGP preferred. Remember: It is not enough to _obey_ Big Brother; you must also learn to *love* Big Brother.

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Re: Anonymous questionnaires
by shamrock＠netcom.com 17 Dec '03

17 Dec '03

You wrote to my question regarding anonymous questionnaires: >I don't know if the researchers are willing to change their methodology just >for you, but it's easy to meet all the requirements you listed: Put your >questionnaire answers in a blank envelope and seal it. Enclose the blank >envelope in another envelope. The outer envelope has your name and various >other information, i.e., everything needed to create the audit trail. When >it arrives, the researchers (whom you must trust) open the outer envelope, >remove the blank inner envelope, and toss it irretrievably into a pile with >all the other blank inner envelopes. There would be no record of which >questionnaire went with which respondent, but there would be a clear record >of who's responded and who hasn't. This system would not provide > 1. Correlate my answers to the answers of my partner. -- Lucky Green <shamrock(a)netcom.com> PGP public key by finger

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Actually using strong crypto on a routine basis.
by John Young 17 Dec '03

17 Dec '03

Responding to msg by jkreznar(a)ininx.com (John E. Kreznar) on Wed, 24 Aug 4:30 AM >Stick to your guns, Rick. Even cypherpunks founders >can become corrupted. No. Tim says: Don't do what I do, do what I say. Do your homework. Clean your room. You embarass me. Get a job. Get a haircut. Get a life. Don't talk back. When I was your age . . . Listen to me . . . Shut the fuck up. I'm sorry, I love you. Every parent of rambunctious kids talks like this. Sigh. John

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Open invitation to attend...
by Jim choate 17 Dec '03

17 Dec '03

Hi all, RoboFest 6 will be held in Austin, TX this fall (the exact date is not final at this time) and I have been advised that my request for TWS to participate has been granted. I would like to extend an invitation to any C-punks out there who will be in the area at that time (exact date will be posted when I get it) are invited to attend. It should be possible to have at least a couple of opportunities for giving speeches or demos if so desired. If this sounds like something you are interested in doing please let me know between now and Jan 1. Hope to see some of you here... Plunk! Ravage (Info)Highway To Hell

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