December 2003 - cypherpunks-legacy

Re: Remailer ideas
by jdd＠aiki.demon.co.uk 17 Dec '03

17 Dec '03

In message <9408051709.AA14763(a)ah.com> Eric Hughes writes: > Jim Dixon analogizes between the Internet and remailer networks. The > analogy has some merit, but yet breaks down badly with the very first > point: > > * all packets should be acknowledged > > This is not the way the Internet works. There are some problems with vocabulary here and some conceptual problems. The objective is a system which is highly reliable and resistant to traffic analysis. If you have three messages in, one 10 bytes long, one 1000 bytes long, and one 1,000,000 bytes long, and you send them out to three different destinations, it does not take genius to see which is which, no matter what order they are dispatched in. But if you send them out as packets, each say 4096 bytes long, with all packets acknowledged, and the routing of the packets is random, and noise has been introduced ... traffic analysis is very difficult. TCP/IP is designed to work in an environment which is unreliable but also unhostile. The sliding window algorithm and acknowledgement at the message level is suitable for that environment. TCP/IP has been optimized for speed. [stuff omitted] > Further, in email, there's currently no notion of a connection. The internal functioning of RemailerNet is not the same as the functioning of the email system. All RemailerNet communications are reliable. Packets are acknowledged and the acknowledgement includes a hash of the packet contents, so that the packet cannot be tampered with. Acknowledgements will in general take different routes from packets. > * users should communicate with trusted gateways > > This point is only half true, because the analogy only subsumes one > kind of trust. For remailers there is both trust in delivery and > trust in silence, the destruction of the message and information about > it. 'Trust in silence' is a good term. This can be enhanced in a number of ways. If you are corresponding with someone you know, you encrypt your messages. If you are corresponding with a stranger, you encrypt your message with the public key of a far gateway; then post it to the far gateway through a near gateway. The near gateway knows who is sending, but cannot read the message and does not know the destination. The far gateway decrypts the message before delivering it, so it knows the message and the destination, but not the sender. If you are sufficiently paranoid, you put your message inside yet another envelope, mailing it through the near gateway to a far gateway, which posts it on to another gateway, which finally posts it to its destination. Remailer gateways should be spread very wide geographically if the network is to be secure. If you are very concerned about anonymity, bounce a message through gateways in, say, the USA, Finland, Russia, and Ireland. If your concerns are about your employer, say, the probability of his getting at four different gateways in four different jurisdictions simultaneously is vanishingly small. If your concerns are about governmental authorities, they are not that much higher. -- Jim Dixon

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Re: Latency vs. Reordering (Was: Remailer ideas (Was: Re: Latency vs. Reordering))
by jdd＠aiki.demon.co.uk 17 Dec '03

17 Dec '03

In message <9408051716.AA14773(a)ah.com> Eric Hughes writes: > Back to the start, I guess. > > > Specifically cryptographic elements are easily added to the system > > * packets can be delayed for random intervals > > Let me repeat: > > REORDERING IS OF PRIMARY IMPORTANCE FOR REMAILER SECURITY. > > ADDING LATENCY IS NOT. No need to shout, we heard you the first time. ;-) In a system that is carrying continuous traffic, random packet delay is functionally identical to packet reordering. If messages are fragmented, random delays on sending packets out is functionally identical to reordering. More importantly, RemailerNet as described defeats traffic analysis by more significant techniques than reordering. Reordering is a weak technique. The introduction of noise, 'MIRV'ing of messages, fragmentation of messages, random choice of packet routes, and encyphering of all traffic are stronger techniques. -- Jim Dixon -- +-----------------------------------+--------------------------------------+ | Jim Dixon<jdd(a)aiki.demon.co.uk> | Compuserve: 100114,1027 | |AIKI Parallel Systems Ltd + parallel processing hardware & software design| | voice +44 272 291 316 | fax +44 272 272 015 | +-----------------------------------+--------------------------------------+

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Re: Remailer ideas (Was: Re: Latency vs. Reordering)
by jdd＠aiki.demon.co.uk 17 Dec '03

17 Dec '03

In message <199408061404.KAA02300(a)cs.oberlin.edu> Spencer Mullen writes: > Jim Dixon writes: > > >Commercial remailers would probably be very concerned with legal > >issues, both criminal (pornography, etc) and non-criminal (copyright > >violations). > > It would seem that remailers shouldn't be anymore accountable for > passing on illicit pornography than the postal services are today. I really do not want to try to argue the legal issues here; I am not a lawyer and claim no expertise. At a practical level, if you were running, let us say, an Internet Service Provider (ISP) and offered remailer services, you would in time attract the business of people who used your services for various unlawful purposes. You could not stop this without going through everyone's private mail. This would itself probably be illegal and certainly would lose you business. I understand that Playboy magazine spends lots of money pursuing people for copyright violations, and that criminal charges have been filed by the authorities in Tennessee or Arkansas against someone in California who sent them pornographic materials over a telephone line. The Post Office has what is called in the UK "crown immunity" against such prosecutions. So do "common carriers" in the USA. They are given special legal status. I do not know, but I believe that the telephone companies are legally common carriers. As a remailer gateway operator, you would probably have to argue things out in court, which could be very expensive. In the case of criminal charges, you would have to expect to lose your equipment for some time, and perhaps your freedom. I suspect that legally the key step would be to never store messages for any period of time. It would be prudent to erase them as soon as their receipt was verified. This would also save disk space, and it would be in line with the 'trust in silence' ethic. I would do this and then publicize the fact that I did so widely. This would discourage public prosecutors, who really don't like to do futile things. And I would incorporate the gateway and make sure it wasn't worth a great deal. This would discourage civil suits; clients get very irritated when they win the lawsuit and find that after all their legal expenses the target has filed for bankruptcy. -- Jim Dixon

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Remailer listings/strategy
by merriman＠metronet.com 17 Dec '03

17 Dec '03

This may have been hashed out in a previous incarnation, but on the subject of remailers and their availability, why not just have each one broadcast a message of it's availability periodically (hourly? every 4 hours?) on, say, the Cypherpunks mailing list. Then, each remailer could also listen in, read in who's up, and if it doesn't hear from a remailer within some period of time (or some number of scheduled broadcasts), assume that it's down until it hears from that system again. This would also allow individuals to maintain personal listings of available remailers, as well, and automate the process of keeping track of what remailers are up/down/available. The additional traffic wouldn't seem to be _too_ much of a burden, those individuals who didn't want the broadcasts cluttering up their mailboxes could filter them out, and doesn't require massive effort or changes to implement (ie, new newsgroups, etc). What blazingly obvious thing am I missing here, or does it make too much sense to work? :-) Dave Merriman Finger merriman(a)metronet.com for PGP2.6ui/RIPEM public keys/fingerprints.

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Re: A Different EFF on DigiTel Bill
by mnemonic＠eff.org 17 Dec '03

17 Dec '03

In article <199408291422.KAA10836(a)pipe3.pipeline.com.778170390>, John Young <jya(a)pipeline.com> wrote: >(If anyone cares, Mike posts zingers and unhealthy thoughts >like c'punks' regularly on list Cyberia-L.) Somebody's got to give those law professors some grief. --Mike -- Mike Godwin, (202) 347-5400 |"And walk among long dappled grass, mnemonic(a)eff.org | And pluck till time and times are done Electronic Frontier | The silver apples of the moon, Foundation | The golden apples of the sun."

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RE: (none)
by Blanc Weber 17 Dec '03

17 Dec '03

From: Jeff Gostin <detailed explanation of 'who cypherpunks' are> So, that's "who cypherpunks". :-) ......................................................................... I really meant to ask 'where cypherpunks'. It had been a whole day & more without the hordes messages and my day seemed empty, without code or purpose, lacking controversy & jibber jabber. Blanc

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Re: RemailerNet
by jdd＠aiki.demon.co.uk 17 Dec '03

17 Dec '03

In message <199408061739.NAA05213(a)bwh.harvard.edu> Adam Shostack writes: > | If you are using unmodified Internet hardware and TCP/IP as the underlying > | transport system, then your point of entry into a remailer network > | definitely knows which machine is originating a message and the point > | of exit definitely knows where it is going. > > IP is not reliable & trustworthy. It it was, RFC931 ident > servers would be useful. ;) Theres source routing to make packets > appear to come from someplace else, and there is outright forgery, > which has limits, but can work quite well. My "if you are using unmodified ..." clause shows that I understand this. You can send from a very large network and forge your TCP/IP or (more difficult) Ethernet source address. But I can sit on the same network, build a table relating TCP/IP to ethernet (or whatever) addresses, and filter out messages that should not be there. There are commerical packages that do this sort of thing. Basically, this is a different topic. One problem is designing a generic software package and set of protocols that will allow you to route mail anonymously. This is a general problem. The hacking of specific networks is a different, if related, problem. -- Jim Dixon

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What are Appropriate Topics?
by Blanc Weber 17 Dec '03

17 Dec '03

From: Timothy C. May "As for pure crypto being discussed on the list, there's a fair amount of that. I've posted my share of explanations of zero knowledge proof systems, dining cryptographers protocols, complexity theory, etc. I'm not saying this to defend myself, per se, but to note that these topics produced almost no discussion, almost no interest. Make of this what you will." I would say some reasons for the silence are that: . those who have read your comments have not thought extremely much about these themselves, so are not ready to add anything at the time. . your treatment of the subject matter was thorough enough that others don't feel the need to add further to your points. . you presented some deep thoughts that require time to digest & process. . the ideas you have about future events may have no present means to carry them out, good as they may be, and the way from point A to point B is not yet possible to achieve, as no practical method or system could yet be constructed. "* what happens to tax collection in an era of unbreakable cyphers? * how will the state react?" I would add: how will the general population react, when their security blanket is rendered ineffective? (* crypto anarchy issues from the perspective of the other side) * what's really holding back the spread of digital cash? What is the status of the work on this? I would like to keep up with its progress, if there are sources for the information. (besides The Economist) * where do we go from here? [Who's 'we', Kimosabe? :>) ] Where was anyone planning to go? There isn't anywhere else to go, physically, so it's necessary to resolve the problem of interacting in the same place at the same time with opposing methodologies. How does that work? (You aren't going to be invisible all the time, nor to everyone.) "..."Cypherpunks write code" is just one manifestation of the idea that we can actually change the world through the technological development of privacy-enhancing systems..." And privacy-enhancement isn't the *only* thing which will change the world, is it? There are other forces of cause-effect and influence which determine people's reactions to each other and to the problems of living. It lies within the broader subject of 'control': self-control, self-determination, as managed by the individual. This is where the controversy occurs - whether any or only some individuals shall be "permitted" to excercise it, and to what tolerable degree, and who shall be the "authority" that makes that decision. Much as some on the list would wish otherwise, "privacy-enhancement" goes in the direction of favoring the individual above the group, and this is difficult for some people to live with. I have seen some of Tim's ideas for future possibilities in terms of things which could come to pass or could be achieved, but I realized that I have not seen anything from him to indicate any projects which he is actually working on to bring these about. You do communicate a lot of information & ideas and do much work of explaining & clarifying fuzzy areas, which is excellent & valuable, but it still waits for others to put together the actual parts & pieces of things, if they are to be brought into actual existence as functional systems which can be employed and which can affect future conditions. "For want of a horseshoe, the war was lost." I would like to read more on what you have to say about this, as you are the pre-eminent poster on the list who likes to digress into abstract discussion. Blanc

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Re: Voluntary Governments?
by Blanc Weber 17 Dec '03

17 Dec '03

From: Hal What does it mean to speak of a government in cyberspace? It is the government in physical space I fear. Its agents carry physical guns which shoot real bullets. ................................................................ Good point. What does it mean to speak of governance (or 'govenment') at all? Questions I would seek to have the answers to, in making decisions about government per se: . Who or what is to be governed? . What is inimical/destructive and to be regulated/prevented, or what is sacred which is to be upheld? . How will anyone come to know the difference? What difference does it really make (to anyone in the real world)? . Who is to do all the work of preventing or upholding (how do they qualify for the job)? . What is to be done about non-conformists to the rules (without contradicting the rules?) . When did you realize that you were an absolute authority on the subject? Blanc

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RE: A Helpful Tip for Impatient Souls
by Anonymous User 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- Tommy the Tourist <nobody(a)CSUA.Berkeley.EDU> (Anon User) wrote: Welcome back, Tommy, we missed you! <g> Hope you're enjoying your new (CSUA) "home"... (Time for everyone to update their "chain.ini" file, BTW.) > Those wishing perhaps the ultimate in Cypherpunks ease-of-use > and greatest peace of mind, may find it useful to simply delete > everything that does NOT come from one of the following email > addresses: > tcmay(a)netcom.com > frissell(a)panix.com > sandfort(a)crl.com But Tommy ... if we did that, we wouldn't be able to read *YOUR* posts, either. Perhaps anyone who had a fetish for "ease-of-use", or was troubled by even seeing "cryptographically INcorrect" ideas (the analog of "politically correct") would tire of Cypherpunks altogether and just read the party line from Sternlight and Co. (tm). <g> The other problem is that if some brave, anonymous soul wanted to, let's say, "leak" the Clipper algorithm to the net, he'd have to forge e-mail from one of the "approved sources" above to gain an audience. However, despite your anonymity, Tommy, don't I see your tongue firmly implanted in your cheek? I sure hope so... I find the posts from the "approved three" individuals highly informative. OTOH, if *THEY* did as you suggested, traffic would be drastically reduced because it would only consist of those three talking amongst themselves. --- Diogenes -----BEGIN PGP SIGNATURE----- Version: 2.6 iQCVAgUBLkOdOeRsd2rRFQ1JAQHi4AP+LuJhvQPRiB0rZvDjuhfZwG+Q95N8WpTt 4lVNjLecXHKjFE6qn6tsed3/Fh/mwQUzRzx4kUihvRxqR3MAoBp1/SREXt+Rsd30 4zsxIs+BDkCCloX7rxVptZLJYG587oaIQOL0Wn/7MiDKChm/LoXrdbRwUeLL2gIU ZvvMDBBuYpI= =Vk7F -----END PGP SIGNATURE-----

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