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Re: Who generates AOCE keys?
by lefty＠apple.com 08 Sep '93

08 Sep '93

Christian Odhner wonders: > >Well, what keeps people from makeing keys with somebody else's name/user >id on them and sending them in to be certified? Where is the >authentication from the key certifier's point of view? The pass phrase. -- Lefty (lefty(a)apple.com) C:.M:.C:., D:.O:.D:.

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The origin of spread spectrum (a true story)
by ccat＠netcom.com 08 Sep '93

08 Sep '93

I have an interesting perspective on spread spectrum encryption, because one of the inventors of this interesting technology was my father. My father,George Antheil,was an avant garde composer living in Hollywood in the late 30's and early 40's. One of his best friends was Hedy Lamarr, the movie actress.One of the facts about Ms. Lamarr that many people were unaware of,was that she was also very intelligent.(She had also just been married and divorced from a Czeck arms magnate,and had spent much time listening to her ex-husbands and friends 'shop talk'.) Anyway, she and my father were very concerned about the Nazi's rise to power,and their U-boat harassment of international shipping.My father, a composer who was fascinated by machines (his composition,"Ballet Mechanique" was one of the very first uses of machines in music.) was working on a composition for several player pianos at the time...This led them to the idea of using two rolls of randomly punched tape to synchronize a receiver and transmitter in a radio controlled torpedo.Using this technology (frequency hopping) their torpedo would be able to be remotely controlled,with virtually no risk of enemy jamming or detection.And there you have it.I have the patent drawings..which were done by both of them.. Theyre simply marvelous.. Several years ago, a guy who was writing a book on the history of encryption called my half-brother to ask him about this story..Correct me if I'm wrong,but I think this was the absolutely first use of spread spectrum encryption... The patent was issued in 1940, and expired in 1957. In 1960 Sylvania, (I think) started manufacturing a radio controlled torpedo ... Hedy Lamarr is still alive and living in Florida, my father died in early 1959. Neither of them ever saw a penny from their pioneering patent. Chris Beaumont (Nutrient Cafe wholesale) - Chris Beaumont ccat(a)netcom.com ccat(a)casa.stanford.edu public key available via finger

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Spread Spectrum- how it works
by You cannot conquer a free man, a man whose mind is free. The most you can do is kill him. 08-Sep-1993 1013 08 Sep '93

08 Sep '93

From: US3RMC::"clark(a)metal.psu.edu" "Clark Reynard" 8-SEP-1993 01:59:18.22 >Then the receptionist returned, and told me that the person from >the engineering department who took care of the phones had indicated >that not even the government had the technology to monitor these >phones. > >Upon asking how and why the government might do this, I received >a rather chilly notification that the engineering department, >was, of course, unwilling to reveal these secrets. Well, it was >worth a try. Actually, they aren't telling you, but SS techniques are published widely in the technical literature. For a relatively accessible and understandable introduction, try the ARRL's book "Spread Spectrum Sourcebook", which describes not only the theory but also the results of the ARRL's experimentation with spread-spectrum technology for radio communications. It's about $30 from any reputable ham radio supply house, and you can mail-order it. [very succintly, SS works by adding a pseudorandom modulation to the transmitter carrier that modulates the signal far far MORE than the actual informational modulation. For example, a 16-bit CRC register feeding back on itself can be used. The output of the CRC register (or any other pseudo-random-number-generator (PRNG) can be used as a modulator in two ways: 1) Frequency hopping: the bits in the CRC or PRNG determine (via a lookup table ("hop set") the new center frequency that the transmitter will send on. This freqency may hop a hundred times or more per second. a) ease of detection: easy- you hear a "click" whenever the transmitter hops onto the freqency you're monitoring b) ease of interception: very hard- if there are a few thousand such signals around, you have to splice together 10 millisecond slices from a thousand different sources- and that's a combinatorially prohibitive problem. You need to know the "hop set" and the particular polynomial or psuedorandom sequence to easily recover the signal. 2) Direct Sequence: the single low-order bit in the CRC or PRNG determines whether the output signal from the transmitter's primary oscillator (already modulated with the user's voice) is inverted or not. This translates to massive phase modulation. If the CRC is clocked at a reasonable rate (say, 1 MHz) then the output signal ends up with a bandwidth of about twice the clocking freqency. a) ease of detection: difficult- the SS signal shows up in a conventional reciever as broadband noise- easy to not notice. b) ease of interception: very difficult- I haven't the foggiest about how to go about it. In either case, to demodulate the signal, one recieves the entire bandwidth, then either hops their first-stage local oscillator (for frequency hopping) or phase-inverts (for direct sequence) the incoming signal. The result is a second-stage signal that can be demodulated by conventional means. The only big trick is to synchronize the PRNG on the reciever to the PRNG on the transmitter. Another advantage to SS is that it tends to "ignore" strong signals in the band- any signal that does not correllate against the PRNG modulation is "spread out" over the entire band by the demodulation operation, while the correct signal energy is concentrated into a small channel. This gives what's called "process gain" and allows a weak spread-spectrum signal to work even in channels that may be dominated by strong conventionally-modulated signals. The ARRL did find that if they knew the bandwidth of the signal they were looking for they _could_ direction-find on it, using wideband recievers and notch filters to remove known conventionally-modulated signals from the signal; once they were close enough to be in the "near field" of the transmitter standard direction-finding techniques were adequate to DF, even if they couldn't understand what was being transmitted, they could find the source. (this was the basis for the FCC's OKing of the use of SS modulation by hams on the 440 and higher bands- that some form of accountability was being preserved). ----- Note that if the PRNG in a direct-sequence SS is replaced by a true random number source, we have the equivalent of a one-time pad and (I believe) complete security. However, since the typical demands of a direct-sequence system for phase information are in the megabits per second, the logistics of "key management" may be utterly impractical. ----- So, if CM was using either modulation method, and used some reasonable PRNG (i.e. one with remappings and hopsets determined by user-genned random numbers) then it is quite possible that the government does not have the technology _deployed_ in the field to intercept them. But if they need it, I'm sure they will figure out how to do it. -Bill

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Super Phones?
by Clark Reynard 08 Sep '93

08 Sep '93

Excerpted from "Wired," August 1993 Playboy (Not THAT Wired) Reprinted without Permission Spread Spectrum technology was developed for the military to allow for high-security communications with crystal-clear reception. Now Cincinatti Microwave has introduced the Escort 9000 ($400), a cordless digital phone with Spread Spectrum that operates on the recently approved 900 MHz radio frequency (that's 20 times higher than the frequency conventional cordless phones use). This marriage of technologies gives the Escort 9000 a remarkable range of about a half maile, superior reception and complete privacy. "Previous attempts to bring Spread Spectrum to the consumer market have been too costly and too bulky for personal use," said Cincinatti Microwave president Jacques Robinson, who sells the phones directly to the public. (Call 800-433-3487 for more information or to order one.) Another company, Cobra, incorporates CM's Spread Spectrum technology into its latest 900 MHz model, and AT & T will introduce a 900 MHz Spread Spectrum phone in the fall. Tropez and Panasonic also offer 900 MHz phones (without Spread Spectrum). It is rumored that the range for some 900 MHz phones could be increased in the future to up to seven miles, which means that one could serve as an around-town alternative to a cellular phone. ---END EXCERPT Now, here's my problem with this nice-sounding product. I called the 800 number to ask for an explanation of this product, which immediately aroused my suspicion. >From my conversation with the receptionist on the other end of the phone, which was somewhat less than informative, the idea of Spread Spectrum technology is that the signal is spread out into individual packets on different wavelengths, then reconstituted at the other end, using some sort of session key generated at the beginning of each transaction. Considering the rather lax security of high-ranking government and military officials with phone technology, recent eavesdropping on Air Force One and the White House most glaringly, I find it difficult to accept as kosher any security scheme created by the government and then offered to private industry. More chillingly, the receptionist told me that no one would be able to perform surveillance on me "except the government." Alerted to this possibility, I immediately asked whether it had the Clipper Chip or the Capstone, or whether there was some sort of key escrow involved. This got me put on hold for a couple minutes. Then the receptionist returned, and told me that the person from the engineering department who took care of the phones had indicated that not even the government had the technology to monitor these phones. Upon asking how and why the government might do this, I received a rather chilly notification that the engineering department, was, of course, unwilling to reveal these secrets. Well, it was worth a try. I gave them my address so that they could send me further information. More reports forthcoming. You can contact Cincinatti Microwave by telephone at: (800) 433-3487 or by snailmail at: Cincinatti Microwave 1 Microwave Plaza Cincinatti, OH 45249 ---- -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.3a mQCNAiyKoFQAAAEEAL22Al/Xil0UER1V7AlS4+eJmOQ6ruIojmq1XCSE7mCqLw3Q ILHBGlcCOl9S20N/8gdge2PfMS9BK794P2r/J3GUjwZw/emKuVm9SXDBpXfdgWax 7jdAGfohRthw/q1+x/z5nJ7gP2C7AZSlsa+XCYYRZbTR2fpaLXzs8jiGc9glAAUT tClSb2JlcnQgVy4gRi4gQ2xhcmsgPHJjbGFya0BueXguY3MuZHUuZWR1Pg== =vJ53 -----END PGP PUBLIC KEY BLOCK-----

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double-blind vs single-blind
by baumbach＠atmel.com 08 Sep '93

08 Sep '93

> ------------------------------------------------------------------------- > To find out more about the anon service, send mail to help(a)anon.penet.fi. > Due to the double-blind, any mail replies to this message will be anonymized, > and an anonymous id will be allocated automatically. You have been warned. > Please report any problems, inappropriate use etc. to admin(a)anon.penet.fi. I have a remailer question. I see a letter posting an offer on the net. The person making the offer is not anonymous. I wish to be anonymous, so I decide to use a remailer to reply. My reply includes a anNNN reply address. If the original poster replies back, an anonymous id will be allocated to him. This isn't any good. When the reply arrives, I will see the new anonymous id of a user whos real username and address I know! My pen-pal would compromise his ability to post anonymously in the future. How can I send an anonymous message that allows a reply that is not anonymous? Keep in mind my pen-pal may not know anything about remailers yet. (I have yet to use them myself :-) Peter Baumbach baumbach(a)atmel.com

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News.cs.indiana.edu
by M..Stirner＠f28.n125.z1.FIDONET.ORG 08 Sep '93

08 Sep '93

Uu> news.cs.indiana.edu oes not appear to be working as an Uu> anonymous news posting gateway. A recent post through my remailer to Uu> alt-security didn't work. I had a similar experience during testing this week. On the other hand, you should have mailed it to alt.security@ rather than alt-security@, according to the latest FAQ. I did successfully test group-name(a)pws.bull.com however. . ~ . M. -- M. Stirner - via FidoNet node 1:125/1 UUCP: ...!uunet!kumr!shelter!28!M..Stirner INTERNET: M..Stirner(a)f28.n125.z1.FIDONET.ORG

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news.cs.indiana.edu *does* work
by sameer＠netcom.com 07 Sep '93

07 Sep '93

The person using my remailer to send news through the posting server incorrectrly used hyphens instead of periods to post news. Sorry about not verifying a simple error like that before posting about it. -- Sameer sameer(a)netcom.com

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Re: Who generates AOCE keys?
by collins＠newton.apple.com 07 Sep '93

07 Sep '93

In the software I used (as recently as last Thursday) the keys are _absolutely_, _positively_ generated locally. Subsequently the public key can be mailed automagically to RSADSI to be incorporated into a certificate which is returned to you. The latest version of RIPEM Mac uses the same procedure for the same functionality. >>[...] users will get certified keys from RSA [...] Yes! _After_ sending RSADSI an uncertified key. >>[the user] can generate a key for use on their network This is the uncertified key. >>Apple believes you'll want publically certified keys Thus, they provide a mechanism to get RSADSI to certify your (self generated) key. Scott Collins | "Few people realize what tremendous power there | is in one of these things." -- Willy Wonka ......................|................................................ BUSINESS. voice:408.862.0540 fax:974.6094 collins(a)newton.apple.com Apple Computer, Inc. 1 Infinite Loop, MS 301-2C Cupertino, CA 95014 ....................................................................... PERSONAL. voice/fax:408.257.1746 1024:669687 catalyst(a)netcom.com

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REMAIL: timestamp
by nobody＠Menudo.UH.EDU 07 Sep '93

07 Sep '93

Well, I decided to comment out the timestamping (what a short lived feature! :-) I'm starting to work on a caching remailer, and the timestamping info could be used to map input and output mailing pairs - especially since I was going to change the stamps to read "X-Time-In:" and "X-Time-Out:". That would defeat the entire purpose of caching... <klbarrus(a)owlnet.rice.edu>

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REMAIL: timestamp
by nobody＠Menudo.UH.EDU 07 Sep '93

07 Sep '93

-----BEGIN PGP SIGNED MESSAGE----- With all the talk of timestamps, I decided to implement a simple timestamp on the remailer at elee9sf(a)menudo.uh.edu. It is by no means a cryptographically secure timestamp. The remailer adds a timestamp header field to outgoing messages. It looks like this: X-Timestamp: hour:min:sec on day:month:year For instance, this message should have one. This nice thing about this is that in the process of stripping mail headers, the remailers will automatically filter the X-Timestamp as well. Thus, if a message is chained through several remailers, only the last remailer's timestamp (if any) will appear in the final message. klbarrus(a)owlnet.rice.edu -----BEGIN PGP SIGNATURE----- Version: 2.3a iQCVAgUBLIzEmIOA7OpLWtYzAQFTFwP9F84EDoIh8XmRDuY4463N5U9jAtLeXBnz WtrGuLF10Vngz3GDkGn4BQF4GQfEUgbYFcosZs3bV8/t0SP487PpnvblV7HG3/rO Fs39piJYTVETnBl14Gt8xVic8GxPvKuAatqk+J9rvKpj1eTklxFT2a/bqOCCJ1FK TuhZQHAVR5U= =U47Z -----END PGP SIGNATURE-----

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