December 2003 - cypherpunks-legacy

Re: LEAF, SS7
by smb＠research.att.com 17 Dec '03

17 Dec '03

The LEAF has many very interesting attributes. As I mentioned earlier, in response to Mike's original question -- yes, there are tremendous advantages to the LEAF for a traffic analyst. But the LEAF itself is encrypted, including the session key, so enemies can't do traffic analysis based on the LEAF. The structure of the LEAF is also a dead giveaway that Clipper is being used -- it's easy to envision a box that has the family key, and tries every LEAF-sized field to see if it decrypts to something that looks right, and in particular has the right checksum. It detects Clipper -- and coupled with a random sequence detector, it detects encrypted, non-Clipper traffic...

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Re: LEAF, SS7
by m5＠vail.tivoli.com 17 Dec '03

17 Dec '03

smb(a)research.att.com writes: > But the LEAF itself is encrypted, including the session key, so > enemies can't do traffic analysis based on the LEAF. "Enemies"? Isn't that a subjective term? :-) > The structure of the LEAF is also a dead giveaway that Clipper is > being used -- it's easy to envision a box that has the family key, > and tries every LEAF-sized field to see if it decrypts to something > that looks right, and in particular has the right checksum. I'm going to make the almost certainly valid assumption that you know more about the way the network works than I do, but my assumption is this: in the wacky scenario I described wherein Clipper devices are installed in the network interfaces "everywhere", then the presence of these identifiable (and identifying!) packets means that a central tap at a regional switching center could concievably perform traffic analysis without the need for taps on local loops anywhere. Is this assumption way wrong? -- | GOOD TIME FOR MOVIE - GOING ||| Mike McNally <m5(a)tivoli.com> | | TAKE TWA TO CAIRO. ||| Tivoli Systems, Austin, TX: | | (actual fortune cookie) ||| "Like A Little Bit of Semi-Heaven" |

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re: LEAF, SS7
by koontzd＠lrcs.loral.com 17 Dec '03

17 Dec '03

> It might even be that Clipper hardware could be >installed right at the network interface. Isn't that nice, the phone >company is going out of its way to safeguard my privacy. Only thing >is, now every circuit I establish is tagged by an LEAF that identifies >me... Actually, providing link encryption via CLIPPER only allows identification of the link, still useful in traffic analysis. (As a quick means of identifying the link.)

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Re: LEAF, SS7
by smb＠research.att.com 17 Dec '03

17 Dec '03

> The structure of the LEAF is also a dead giveaway that Clipper is > being used -- it's easy to envision a box that has the family key, > and tries every LEAF-sized field to see if it decrypts to something > that looks right, and in particular has the right checksum. I'm going to make the almost certainly valid assumption that you know more about the way the network works than I do, but my assumption is this: in the wacky scenario I described wherein Clipper devices are installed in the network interfaces "everywhere", then the presence of these identifiable (and identifying!) packets means that a central tap at a regional switching center could concievably perform traffic analysis without the need for taps on local loops anywhere. Is this assumption way wrong? I suspect that you'd have too much data -- you'd have to be able to scan every part of every conversation. If you're going to go to those lengths, you'd do just as well to tap the signaling channels instead -- a lot less data, and most of it organized the way you want it.

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Re: Clipper and Traffic Analysis
by rudy (r.) rawlins 17 Dec '03

17 Dec '03

In message "Clipper and Traffic Analysis", pmetzger(a)lehman.com writes: > > Normally, one can only determine the endpoints of a conversation. With > clipper, however, one can deduce a lot more, since when people move > around, go to hotels, phone booths, etc, you can still track their > clipper serial numbers. > > Perry > Maybe we are missing something here, when people move around if they simply use their hotels phones, phone booths, et al, how can one track their clipper serial number? Unless there is a personal Clipper serial number? I do not see any extra info being garnered from Clipper phones, just less. Consider the case where there is a wiretap in progress: In the past one end was tapped and both sides of the converstion were heard. You could always find out who was calling, but you could not go and bug the calling party's phone without a court order. With Clipper, you tap the outbound voice/data, but every inbound voice has to be decoded with its own key. Now will the wiretap allows blanket decryption for all Clipper phones? and if so where does the tap begin and end. If no blanket decryption is allowed then must they record outgoing voice/data and based on the content of one side of the conversation convince a judge to let them decode the other side? Both scenario is problematic. If I'm cop and the suspect does not have a Clipper phone at home? can I choose which end of the switch to tap? I would choose the analog side that still has voice -- both voices, so even if the network is Clippered, why go through the hassle of managing keys when I can always hook onto an old fashioned analog voice line. Am I seeing correctly or did I miss something?

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Re: Detweiler remailer abuse
by qwerty＠netcom.com 17 Dec '03

17 Dec '03

-----BEGIN PGP SIGNED MESSAGE----- To lefty, (Skip to end for remailer discussion). -----BEGIN POINTLESS FLAME BLOCK----- When a control freak has zero to actually say, yet has been infuriated, he turns to personal attack. If I am infuriating the control freaks, then I am doing my job admirably. >I suggest a short chat with Mr. Dictionary to determine the actual >definition of the word "censorship". In the immortal words of Inigo >Montoya, "You keep saying that, but I don't think it means what you seem >to believe it does." Which dictionary do you own? I personally own THREE 4 inch thick dictionaries, all modern. They cost me hundreds. I have a wooden stand to hold them up. As I am at lab, I do not have them available however and will have to go to the library.... I'm back. Censor: A supervisor or inspector especially of morals and conduct. An official empowered to examine written or printed matter (as manuscripts of books or plays) in order to forbid publication, circulation, or representation if it contains anything objectionable. An officer or official charged with scrutinizing communications to intercept, suppress, or delete material harmful to his country's or organization's interests. One who lacking official sanction but acting in society's interests scrutinizes communications, compositions, and entertainments to discover anything immoral, profane, seditious, heretical or otherwise offensive. Examine, cut out, parts of (a book, etc.); act as a censor. >>And after all, he wasn't the one who wrote that "Blacknet" blurb. >Was there a point to this statement? Yes. >Do you believe that drunk drivers should not be held responsible for their actions because they don't build their own cars? No. >Please feel entirely free to avoid using the old one while you wait >patiently for the new and perfect one to show up. I suggest you avoid >posting any further until you have _real_ _encryption_ running in your >laptop and _optical_ _fiber_ connecting you to all the places with which >you might consider communicating. This is good advice to anyone interested in maintaining privacy in a public forum. >>I can't take the IDEAL of the First Amendment lightly >>enough to do so either. >OK, I see we can add the First Amendment to the list of subjects on which >you are essentially totally ignorant. When you finish with Mr. >Dictionary, you might try puzzling out Mr. Bill of Rights. _It_ doesn't say >what you apparently think it does, either. Ideal: A conception of something in it's absolute perfection. An honorable or worthy principle or aim. First Amendment: Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances. I find it unfortunate that those who wrote the Bill of Rights limited its scope, to not apply also to industry and other organizations. And it is people who nit-pick the wording of the Constitution and its amendments who are turning the USA into a repressive state. Burn baby, burn. >Not nearly as amusing as _I_ find it to see know-nothing children >attempting to impress the big kids with their general level of >uninformedness. Part of the problem with this command-line interface we are using is that you can't see me, and thus you can't know me, for who I am as a person. Flaming one another isn't what we need. If you feel someone misunderstands something that you understand better, educate them. But realize that most cases of one person becoming infuriated at another stem from misunderstanding, a failure to communicate. So tell my why I should censor Larry 'cause I don't see why I should. It's a lost cause. He will simply aquire other accounts, or telnet to port 25 of a remailer and fake his address, but this time with greater ambition to do damage. The "know-nothing children attempting to impress the big kids with their general level of (sic) uninformedness" who wrote that Blacknet thing should think again about getting their thrills out of illegal activity, real or imagined. You wouldn't have this Detweiler problem if you called yourself "libertarians" instead of "Cypherpunks". You would increase you level of support by orders of magnitude as well. -----END POINTLESS FLAME BLOCK----- This following was my response to a discussion in e-mail. I expressed that I think the MEANS suggested to me to censor Detweiler would so more harm than good. It was pointed out to me that at least it would make it less convenient for him to abuse the remailers.... >And that extra work will anger him and fill him with the unfortunate >drive to do more damage, since in his mind our trying to fight him >means he has to try so much harder to point out to us whatever the hell >he is trying to point out. >Julf cutting off someone's account isn't effective either for someone >like Detweiler. I myself found out that I could telnet to anon.penet.fi >port 25 and simply fake my incoming address, and thus gain access to as >many new anon.penet.fi addresses as I wanted. >Again, I wish we could get a net modeled on the postal service, in >which there WAS NO "From: qwerty-remailer(a)netcom.com" in the headers. >The day someone posts kiddie porn via qwerty is the day I tell Netcom and >the police that I am running remailer, and that I will shut it down to >avoid this again, but that if they want to know who posted it they need >to look at Netcom's sendmail logs, and follow them to the next remailer. >And to avoid Detweiler becoming angry enough to post kiddie porn via >qwerty, I wish not to try to block him in ineffective ways. >What we need is an abuse filter, not a Detweiler filter, because he >can always post kiddie porn under another name. And honestly, I dont' >think he would ever post kiddie porn, or carry out any serious illegal >abuses. He could however make his point a lot clearer were he to >state it up front. His pranks do serve to warn us about possible >REAL abuses. And I wrote this, when told that Larry wasn't a responsible net.citizen, doesn't deserve to be treated as such: >I agree, but I'm not sure if the means suggested to me are going to >be effective. He will just aquire other accounts, or telnet to post >25 of a remailer, to get through, and this time with more passion >about doing real harm. Fight him and he'll fight back, with greater >ambition. I don't know the real answer. And are those who wrote that >Blacknet thing "responsible net.citizens"? If anyone should have been >censored, it was he who starting sending those things out in the first >place. >And I spoke of the "IDEAL" of the first amendment, which to me means >stopping someone from using a PUBLIC forum, normally available to all, >from expressing his views. If his Blacknet posts via Hal's remailer >be called performance art, and in a way they CAN, then I cannot YET >bring myself to censor them. And indeed part of the problem is that I >do NOT yet understand well enough about the internet, Blacknet, >Cypherpunks, and Detweiler to be confident that I'd be doing the right >thing. -=Xenon=- -----BEGIN PGP SIGNATURE----- Version: 2.3 iQCVAgUBLWD6lQSzG6zrQn1RAQFzUwP/cDRVTBeW/76wywDYKyzShbiNq5DQsAFG I72DHYailmY63mwAaMYmXeDnN21bJaUUkWd+JaWt0EzEPo6ruPVA44OphWsxoZy3 9BRr7ZWijIs4BlHMMtaObuRooM7MeCzfSjpU1C2ahB89+E8byWPpFyVzlIUiYuht 5CaHwkkeUzc= =el7y -----END PGP SIGNATURE-----

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Re: Clipper and Traffic Analysis
by Perry E. Metzger 17 Dec '03

17 Dec '03

"rudy (r.) rawlins" says: > > Normally, one can only determine the endpoints of a conversation. With > > clipper, however, one can deduce a lot more, since when people move > > around, go to hotels, phone booths, etc, you can still track their > > clipper serial numbers. > > > > Perry > > > > Maybe we are missing something here, when people move around if they > simply use their hotels phones, phone booths, et al, how can one track > their clipper serial number? Unless there is a personal Clipper serial > number? I do not see any extra info being garnered from Clipper phones, > just less. Perhaps this is not obvious to others, so I'll be more explicity. If you use a clipper phone at home, the cops can determine your serial number by tapping your line. Then, if you take your phone with you (the little portable AT&T "bump in a cord" is designed for this) everywhere you go you are signaling where you are. Perry

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Re: ?
by walter kehowski 17 Dec '03

17 Dec '03

yahoo seriuos!

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?
by hansen＠Iowa.Physics.UIowa.EDU 17 Dec '03

17 Dec '03

Is this serious?

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Re: Clipper and Traffic Analysis
by norm＠netcom.com 17 Dec '03

17 Dec '03

At 12:25 2/15/94 -0500, Peter Wayner wrote: >I believe the LEAF field is useful, but not too useful. >Here are my points: > ... >*) On the other hand, the system really isn't anywhere near as >useful as the phone number of the person calling. There will >be no map between LEAF id numbers and people. Such a map would >quickly get out of date as people traded phones etc... If Public switches are made 'tap ready' then such a map may easily be made and kept up to date without human erffort. ...

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