- cypherpunks-legacy - lists.cpunks.org

RE: questions about bits and bytes
by Blake Coverett 17 Dec '03

17 Dec '03

> At 06:29 PM 4/10/96 -0700, Simon Spero wrote: > >No, bytes are no always 8 bits - some machines use(d) 9-bit bytes. > > I notice you gave no examples. Why is that? > > Jim Bell > jimbell(a)pacifier.com In a past life I worked on a Honeywell DPS8 box that had 36 bit words and 9 bit bytes. -Blake (recalling the random evil flags that extra bit was used for)

2 1

Re: Digital Cash Escrow
by jim bell 17 Dec '03

17 Dec '03

At 09:17 AM 4/11/96 -0500, John Deters wrote: Go dig up the manuals for a >UNIVAC 1100, Jim. Why do you think the RFCs for IP specifically refer to >"octets" as opposed to "bytes"? Because (they explain) "octet" is >unambiguous, which then infers a certain ambiguity to "byte", now, doesn't it? Wasn't the original development of the Internet done in the middle 1960's? And thus, does its development pre-date the coinage of the term, "byte"? If that's true, doesn't this answer your question? The terminology used for the definition of a standard often tends to be frozen in time. Lacking the term "byte" they used "octet." The subsequent invention of the term "byte" would not have displaced the original term, at least in Internet standards.

2 1

Re: RC4 on FPGAs (Was: Bank transactions on Internet)
by shamrock＠netcom.com 17 Dec '03

17 Dec '03

At 13:52 4/10/96, Ian Goldberg wrote: >Coincidentaly enough, this is part of my project for my Hardware class. >I'll let you know when I have it working. I'm using Altera FLEX 81188s, >though the 10K models (with built-in RAM) would be _way_ faster... Perhaps someone with access to such a beast would donate one to this very promising student? Seems like a good cause to me. :-) -- Lucky Green <mailto:shamrock@netcom.com> PGP encrypted mail preferred.

1 0

GPS-based authentication
by Peter Trei 17 Dec '03

17 Dec '03

Ms Denning, Mr. MacDoran I've read with interest your proposed GPS-based authentication mechanism (it was posted to the cypherpunks mailing list). Can you confirm that you wrote this? Some people on the list think it may be a forgery. The participants of the list have noted some apparent vulnerabilities in the system, and I am curious as to how you address them. If you respond to me and give permission, I'll forward your response to the list. The problems are two-fold: 1. The system is easily spoofed. 2. It leaks sensitive location data. You say: " The signature ... is formed from bandwidth compressed raw observations of all the GPS satellites in view." " The location signature is virtually impossible to forge at the required accuracy. This is because the GPS observations at any given time are essentially unpredictable to high precision due to subtle satellite orbit perturbations, which are unknowable in real-time, and intentional signal instabilities (dithering) imposed by the U.S. Department of Defense selective availability (SA)." Could you substantiate this claim? Is there any reason a spoofer could not do the following? 1. Set up a receiver near (within a 1000 miles or so) of the site he is trying to spoof (he needs to be able to see roughly the same satellites as the spoofed site). 2. Extract from the signal he receives the psudo-random sequence sent from each satellite. 3. Buffer the sequence from each satellite for a brief period (the extreme case is 42 msec, the time it takes light to travel the diameter of the earth). 4. Re-assemble the aggregate signal with the appropriate delays for the location he is trying to spoof. These delays can be pre-computed. 5. Modulate a simulated 17 cm carrier appropriately to produce a synthesized signal, identical to that received at the location to be spoofed, and use that to fake his location. I note that there is commercially available test equipment to simulate GPS satellites, which transmit a signal appropriate for any location you dial into them (btw, setting one of these up near a location using your protocol leads to an interesting denial-of-service attack, since you can overwhelm the satellite signal with a false one giving a bogus location). Even if the spoofer has to extract sequence data from the real satellites, the storage requirement is not onerous, since he already knows just how long he has to delay each satellite's signal, and need buffer only the appropriate chunk for each satellite. While this *does* result in a slight delay while the sequence data for each satellite is gathered, the extreme case is 42 ms. Internet transmission delays on the order of 100 ms are common, so your system will have to accept location data which is this old. The computational load neccesary to spoof the signal is not excessive - it's essentially the reverse of that used to extract location data from the aggregate signal, a process which is not a one-way function. Thus, the signal can be spoofed. Second, your system broadcasts potentially sensitive location data. Your protocol will be a gold mine for the traffic analysts The data can be used for later spoofing attacks, or, in an operational situation, to target munitions. While encrypting the link can protect this data, if you can use encryption, you can also use digital signatures for authentication. Finally, GPS receivers don't work too well in steel-framed buildings. There are substantial shielding and multipath problems ( for your system to work, the antenna needs to be near the originating node, not on the roof). You do not appear to address these problems. Peter Trei trei(a)process.com -------------------------------------------------------- I append the original article, as it appeared on the list on April 10th. -------------------------------------------------------- Location-based System Delivers User Authentication Breakthrough By Dorothy E. Denning and Peter F. MacDoran Copyright(c), 1996 - Computer Security Institute - All Rights Reserved Top - Help Existing user authentication mechanisms are based on information the user knows (e.g., password or PIN), possession of a device (e.g, access token or crypto- card), or information derived from a personal characteristic (biometrics). None of these methods are foolproof. Passwords and PINs are often vulnerable to guessing, interception or brute force search. Devices can be stolen. Biometrics can be vulnerable to interception and replay. A new approach to authentication utilizes space geodetic methods to form a time- dependent location signature that is virtually impossible to forge. The signature is used to determine the location (latitude, longitude and height) of a user attempting to access a system, and to reject access if the site is not approved for that user. With location-based controls, a hacker in Russia would be unableto log into a funds transfer system in the United States while pretending to come from a bank in Argentina. Location-based authentication can be used to control access to sensitive systems, transactions or information. It would be a strong deterrent to many potential intruders, who now hide behind the anonymity afforded by their remote locations and fraudulent use of conventional authentication methods. If the fraudulent actors were required to reveal their location in order to gain access, their anonymity would be significantly eroded and their chances of getting caught would increase. Authentication through geodetic location has other benefits. It can be continuous, thereby protecting against channel hijacking. It can be transparent to the user. Unlike most other types of authentication information, a user's location can serve as a common authenticator for all systems the user accesses. These features make location-based authentication a good technique to use in conjunction with single log-on. Another benefit is there is no secret information to protect either at the host or user end. If a user's authentication device is stolen, use of the device will not compromise the system but only reveal the thief's location. A further benefit of geodetic-derived location signatures is that they provide a mechanism for implementing an electronic notary function. The notary could attach a location signature to a document as proof that the document existed at a particular location and instant in time. The use of geographic location can supplement or complement other methods of authentication, which are still useful when users at the same site have separate accounts and privileges. Its added value is a high level of assurance against intrusion from any unapproved location regardless of whether the other methods have been compromised. In critical environments, for example, military command and control, telephone switching, air traffic control, and banking, this extra assurance could be extremely important in order to avoid a potential catastrophe with reverberations far beyond the individual system cracked. How it works International Series Research (Boulder, CO) has developed a technology for achieving location-based authentication. Called CyberLocator, the technology makes use of the microwave signals transmitted by the twenty-four satellite constellation of the Global Positioning System (GPS). Because the signals are everywhere unique and constantly changing with the orbital motion of the satellites, they can be used to create a location signature that is unique to a particular place and time. The signature, which is computed by a special GPS sensor connected to a small antenna, is formed from bandwidth compressed raw observations of all the GPS satellites in view. As currently implemented, the location signature changes every five milliseconds. However, there are options to create a new signature every few microseconds. When attempting to gain access to a host server, the remote client is challenged to supply its current location signature. The signature is then configured into packets and transferred to the host. The host, which is also equipped with a GPS sensor, processes the client signature and its own simultaneously acquired satellite signals to verify the client's location to within an acceptable threshold (a few meters to centimeters, if required). For two-way authentication, the reverse process would be performed. In the current implementation, location signatures are 20,000 bytes. For continuous authentication, an additional 20 bytes per second are transferred. Re- authorization can be performed every few seconds or longer. The location signature is virtually impossible to forge at the required accuracy. This is because the GPS observations at any given time are essentially unpredictable to high precision due to subtle satellite orbit perturbations, which are unknowable in real-time, and intentional signal instabilities (dithering) imposed by the U.S. Department of Defense selective availability (SA) security policy. Further, because a signature is invalid after five milliseconds, the attacker cannot spoof the location by replaying an intercepted signature, particularly when it is bound to the message (e.g., through a checksum or digital signature). Continuous authentication provides further protection against such attacks. Conventional (code correlating and differential) GPS receivers are not suitable for location authentication because they compute latitude, longitude and height directly from the GPS signals. Thus, anyone can report an arbitrary set of coordinates and there is no way of knowing if the coordinates were actually calculated by a GPS receiver at that location. A hacker could intercept the coordinates transmitted by a legitimate user and then replay those coordinates in order to gain entry. Typical code correlating receivers, available to civilian users, are also limited to 100 meter accuracy. The CyberLocator sensors achieve meter (or better) accuracy by employing differential GPS techniques at the host, which has access to its own GPS signals as well as those of the client. DGPS methods attenuate the satellite orbit errors and cancel SA dithering effects. Where it works Location-based authentication is ideal for protecting fixed sites. If a company operates separate facilities, it could be used to restrict access or sensitive transactions to clients located at those sites. For example, a small (7 cm x 7 cm) GPS antenna might be placed on the rooftop of each facility and connected by cable to a location signature sensor within the building. The sensor, which would be connected to the site's local area network, would authenticate the location of all users attempting to enter the protected network. Whenever a user ventured outside the network, the sensor would supply the site's location signature. Alternatively, rather than using a single sensor, each user could be given a separate device, programmed to provide a unique signature for that user. Location-based authentication could facilitate telecommuting by countering the vulnerabilities associated with remote access over dial-in lines and Internet connections. All that would be needed is a reasonably unobstructed view of the sky at the employee's home or remote office. Related application environments include home banking, remote medical diagnosis and remote process control. Although it is desirable for an antenna to be positioned with full view of the sky, this is not always necessary. If the location and environment are known in advance, then the antenna can be placed on a window with only a limited view of the sky. The environment would be taken into account when the signals are processed at the host. For remote authentication to succeed, the client and host must be within 2,000 to 3,000 kilometers of each other so that their GPS sensors pick up signals from some of the same satellites. By utilizing a few regionally deployed location signature sensors (LSS), this reach can be extended to a global basis. For example, suppose that a bank in Munich needs to conduct a transaction with a bank in New York and that a London-based LSS provides a bridge into Europe. Upon receiving the location signatures from London and Munich, the New York bank can verify the location of the Munich bank relative to the London LSS and the London LSS relative to its own location in New York. The technology is also applicable to mobile computing. In many situations, it would be possible to know the general vicinity where an employee is expected to be present and to use that information as a basis for authentication. Even if the location cannot be known in advance, the mere fact that remote users make their locations available will substantially enhance their authenticity. In his new book, The Road Ahead, Bill Gates predicts that wallet PCs, networked to the information highway, will have built-in GPS receivers as navigational assistants. With the CyberLocator technology, these PC receivers can also perform authentication while being a factor of ten less expensive than conventional code correlating receivers (most of the processing is executed in the host rather than the remote units), which only achieve 100 meter accuracy, and a factor of a hundred less expensive than conventional DGPS receivers. Location-based authentication is a powerful new tool that can provide a new dimension of network security never before possible. The CyberLocator technology is currently operational in a portable demonstration. Dorothy E. Denning is professor of computer science at Georgetown University (Washington, D.C.) and consultant to ISR. She can be reached at 202-687-5703 or denning(a)cs.georgetown.edu. Peter F. MacDoran is president and CEO of International Series Research, Inc. (Boulder, CO). He can be reached at 303-447- 0300 or pmacdorn(a)isrinc.com. $0$AD Peter Trei Senior Software Engineer Purveyor Development Team Process Software Corporation http://www.process.com trei(a)process.com

1 0

liibulletin - Announcement of New Related Services (fwd)
by Rich Graves 17 Dec '03

17 Dec '03

I have no joke. I just like saying, "barratry.law.cornell.edu." Oh, and the full-text availability of recent net.relevant decisions (numero dos) should be useful to somebody. So how do I get to be the Unabomber's pen pal? Hmm, what jail was he in again? I wonder if they'll accept packages for him with excessive postage. -rich and now, back to bilingual 9-bit-punks ---------- Forwarded message ---------- Date: Thu, 11 Apr 1996 12:13:36 -0400 From: "Peter W. Martin" <martin(a)LII.law.Cornell.EDU> To: Multiple recipients of list <liibulletin(a)listserv.law.cornell.edu> Subject: liibulletin - Announcement of New Related Services [...] The announcement: ================================================================ April 11, 1996 Two New Services from Cornell's Legal Information Institute I. Landmark Supreme Court Decisions Cornell's Legal Information Institute is pleased to announce the addition of important "new" decisions to its Supreme Court collection. Under a license, recently concluded with InfoSynthesis, publishers of the USSC+ CD-ROM, the LII will be placing a steadily growing number of historic decisions on its WWW server. The first of these historic decisions are now in place, including: Brown v. Board of Education (I and II), New York Times v. Sullivan, The "Pentagon Papers" case, and Bakke. These join an existing collection of important decisions dealing with privacy, the First Amendment, administrative law, patents, and copyright. All decisions in this collection carry links to current U.S. Court of Appeals decisions in which they are cited (using the LII's full-text index of Court of Appeals decisions on the Net) and to other related documents in the LII collection (e.g., statutes, topical summaries, the Constitution). The "new" cases are accessible from the base address for Supreme Court materials http://www.law.cornell.edu/supct/ or directly at http://www.law.cornell.edu/supct/cases/historic.htm Additions will follow on a regular basis. II. LII's Eye on the Courts Joining the current awareness services already offered by Cornell's LII -- BigEar (http://barratry.law.cornell.edu:5123/notify/buzz.html) liibulletin and liibulletin-ny (see http://www.law.cornell.edu/focus/bulletins.html) -- is a new WWW page providing links to newsworthy decisions handed down by any of the many appellate courts now covered on the Net, along with relevant background, when available. LII's Eye on the Courts can be found at http://www.law.cornell.edu/focus/liieye.htm ================================================================

1 0

Re: No matter where you go, there they are.
by Hal 17 Dec '03

17 Dec '03

I think the various comments are correct that Denning's scheme won't work across the Internet as it currently exists. Any network with latencies in the multiple milliseconds and up will allow the fraud where the remote node lies about its latency in order to allow it to move some of the received data "forward in time", which is necessary but would not be possible if latency were known and fixed. Note however that Denning did not mention the Internet in her spiel. I believe her method would be workable across lower latency networks, if such exist or eventually exist. Perhaps direct connections or leased lines would provide low enough latency; I don't know. In any case networks are likely to become faster in the future and her method might eventually work. Actually the issue is not just latency but whether the latency can be lied about, and for some kinds of networks that would be harder. The method of using authenticated devices which provide timestamped data from satellites not visible to the authenticating site does not need to provide that data in real time. Even if it is delayed so it comes in later than the data from the remote site, the verifying site can still use it to calculate what the remote site should have been seeing, and so get the benefit of using timings from all the satellites visible to the remote site (again, assuming the remote site itself has a low latency connection to the authenticating site). They do mention that in urban or other obstructed locations a partial view of the sky may be adequate. But of course if all the satellites visible to the remote site are in the south, it can move its apparently location north by using older data. So for the system to work there must be satellites visible in all parts of the sky (no line you can draw through your location which puts all satellites on one side of that line). Hal

2 1

Re: On computer face recognition:
by geeman＠best.com 17 Dec '03

17 Dec '03

There was a piece, I _think_ in Scientific American, tho it might have been an AI journal, on face recognition by use of neural nets together with what were called "eigenface" images: These eigenfaces each have specific characteristics, which when combined together can closely approximate a specific face image. The target face was analyzed in terms of closeness-of-match to a small set of eigenfaces, on the order of 5 to 8, I think. Results of course were promising (else why write about it, eh?) if not excellent. At 12:14 PM 4/11/96 -0700, you wrote: >At 10:02 PM 4/10/96 -0700, you wrote: >> >>On computer face recognition: >> >> >>>> Shaving probably will not be a problem, but holding your head at a >>>> slightly different angle... will screw up the system totally, >>>> unless the system has radically improved since the last time I read >>>> up on it. >> >>At 11:45 AM 4/9/96 -0500, K00l Secrets wrote: >>> Well, the systems I have seen are quite good at finding people's eyes. >>> Scaling (for distance), and rotation (for the angle of your head) >>> therefore don't really confuse the system once it has your eyes. >> >>Finding the eyes can only control for rotations in the plane of >>the image, when you tilt your head to one side. They cannot >>handle the much more common case of 3D rotations, where you >>look slightly to the right or slightly to the left of camera. >>Facial expressions also throw them badly. >> > >Take a peak at http://www.neci.nj.nec.com/homepages/lawrence/papers. One of >Lawences papers is on using Neural networks to recognize faces. Methinks >that the state of the art is advancing rapidly and such problems as not >looking at the camera or changing your expression are rapidly being overcome. > > >===================================== >dwl(a)hnc.com > >Zippity do da, zippity ah, my oh my what a wonderful day. >Ya right, and hear I am without time to finish a cup of coffee. > >

4 3

Re: Scientologists may subpoena anonymous remailer records
by Rogue Agent 17 Dec '03

17 Dec '03

Timothy C. May (tcmay(a)got.net) wrote: |At 8:12 PM 4/10/96, Steve Reid wrote: [...] |>I don't really know much about remailers, but I don't think there's much |>to know... If I'm mistaken about any of the above, I'm sure someone will |>correct me. | |Glad to oblige. I note also that Jim Byrd and Jim Warren are unclear on |some details. (To Jim Byrd, that "alumni account at Cal Tech" that you |mentioned was one of the Cypherpunks remailers at Caltech that our own |pioneering Hal Finney runs.) Incorrect. The account was tc(a)alumni.caltech.edu, which is not the same as Hal's remailer at hal(a)alumni.caltech.edu. Just an odd coincidence they were on the same machine. There's a whole saga about how CoS tracked the guy down, it's quite a story. Rather than go into it here and leave things out or confuse them further, check out http://www.cybercom.net/~rnewman/scientology/anon/penet.html for a clear, concise explanation of the whole bizarre affair. Check out Ron's "CoS vs the Net" page while you're at it, at http://www.cybercom.net/~rnewman/scientology/home.html. |Cypherpunks remailers account for something like 29 out of 30 of all the |world's remailers, by site count, though not volume. Sophisticated users |know that the Cypherpunks model is the only robust one; Julf's approach |has an ecological niche, but is highly vulnerable to the very subpoena |approach used recently (not "several years ago" as Jim Warren says). It's also suceptible to hacker attack, as happened a few years ago. "Information wants to be free" is not a political statement, it's a fact of nature. One property of information is that it tends to spread. If you don't want the information to spread, don't store it. RA agent(a)l0pht.com (Rogue Agent/SoD!/TOS/attb) - pgp key on request ---------------------------------------------------------------- The NSA is now funding research not only in cryptography, but in all areas of advanced mathematics. If you'd like a circular describing these new research opportunities, just pick up your phone, call your mother, and ask for one.

1 0

Senate Cmte to hear Testimony About Bernstein Case
by Cindy Cohn 17 Dec '03

17 Dec '03

The Senate Judiciary Committee's Subcommittee on the Constitution, Federalism, and Property Rights will hear testimony from Cindy Cohn, lead counsel in the Bernstein case on March 17, 1997. The hearing, entitled "Privacy in the Digital Age: Encryption and Mandatory Access," will begin at 10:00 a.m. in Room 226 of the Dirksen Senate Office Building. The Subcommittee is chaired by Senator John Ashcroft of Missouri. Ms. Cohn will discuss the Bernstein case as well as the inherent constitutional problems raised by the proposals for domestic cryptography controls. This will be the first time that the Congressional committees considering proposed cryptography legislation have heard testimony from those directly involved in the legal challenges the current regulations. The government's appeal of the Bernstein case, which was argued on December 8, 1997, is still pending with the 9th Circuit. A decision is expected in the next few months. ****************************** Cindy A. Cohn, Cindy(a)McGlashan.com McGlashan & Sarrail, P.C. 177 Bovet Road, 6th Floor San Mateo, CA 94402 (650) 341-2585 (tel) (650) 341-1395 (fax)

1 0

get me off
by JO COOPER 17 Dec '03

17 Dec '03

Hello- ANYONE!!! Please, my young son subscribed me to this -whatever you are- and I cannot get off- I do not want any e-mail from you. Can I please get instructions as to how to stop this? Thank you

2 1