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| 2004/7/12-13 [Science/Space, Transportation/PublicTransit] UID:32232 Activity:very high |
7/12 Question about the BART ticket encoding system. Do they attach a
unique id to each card, and have all the stations connect to a
central computer that keeps track of the states (which is more secure
but less reliable because in the 70s the network communication was
not as reliable as now), or do they encode the actual amount of
money onto each card (which is more fault tolerant to network
noise, etc)? ok thx.
\_ I can't speak for BART but Singapore's MRT system uses RFID
cards for both bus and train services. AFIK, it would be
really expensive to have RFID cards self modifying (especially
when they have no batteries). It would be easier to use a
centralized server and that's probably what they do.
\_ Are you sure it's RFID and not some sort of induction mechanism?
I think that's what RATP (Paris metro) use. About contactless
smart cards: http://tinyurl.com/6su5r -John
\_ The latter. I have fantasized about getting a card reader
and writer and making my own BART cards. It uses some
simple encoding, if I remember correctly. I can dig up
my research no this, if you like.
\_ You know this is how one of the hosts of Off the Hook got
a felony conviction, right? It's not worth it. If they catch
you, expect the whole paranoid Mitnick style treatment by the
courts.
\_ He got a felony conviction for making a fake BART card?
I find this hard to believe. URL please.
\_ it was MTA in new york, and not BART. I don't have a
url, and he doesn't discuss the details of his case
on the radio, but he's definitely on probation from
felony charges, and whatever he did was
definitely involving MTA cards in some way.
\_ "Your honor, he was 'hacking' BART, a vital public resource.
If his plan had been allowed to spread, it would have had
serious impacts upon BART's ability to evacuate people in
the event of a disaster. We ask that the court consider
the defendant to be an enemy combatant."
\_ Dude, you don't have to be declared an enemy combatant
for the government to make your life into a living hell.
I think the PP is pointing out that a felony crime
coupled with any electronic fu is likely to make a prime
target for investigation by the Dept of Homeland Sec.
Welcome to the New America.
\_ it's not the New America, and has nothing to do
with DHS. The paranoid idiocy about computer
related crime goes back to at least when I was
in highschool in the early 90s. My highschool physics
teacher atually testified that some idiot who was caught
with bomb related stuff on his bbs and some stolen shit
in his home (which the cops raided swat style) was
"neither evil nor a genius." They really wanted
to throw the book at him becuase prosecuters get all
excited about the "evil genius" thing for some reason.
also, google "ed cummings" to learn just how far law
enforcement will go to brutalize a small time hacker,
even before 9/11.
\_ And soon I will have understanding of videocassette
recorders and car telephones. And when I have
understanding of them, I shall have understanding
of computers. And when I have understanding of
computers, I shall be the Supreme Being!
\_ could you please? My point is to not hack the system, but to
research how engineering decisions are made, why, in what time
frame, etc. I'm conducting a technology literary survey,
thanks, -op
\_ Does it have to be bart or can it be any other eng.
system? Applied Crypto and Practical Crypto have
several examples of eng. design decisions. Also
look for books about Gemini and Apollo (the story
of why LOR was chosen is good example of eng. in
the real world)
\_ What's LOR?
\_ Lunar Orbit Rendezvous. There were three
different proposals to get to the moon:
1. Direct
2. Earth Orbit Rendezvous (EOR) - Launch
the bits into space separately, link
up in Earth orbit, go to the moon, land
and come back
3. Lunar Orbit Rendezvous (LOR) - Launch
this bits into space separately, link
up, go to the moon, land only part of
the craft on the moon, link back up
in orbit around the moon and come back.
LOR was the most/least complex depending
on your point of view. Most complex because
it has so many places where it could go
wrong. Least complex because it required
smaller rockets and smaller simpler lander.
Gemini is also of interest, because that
was the platform that proved that rendevous
and other systems could work.
For more info see:
http://oea.larc.nasa.gov/PAIS/Rendezvous.html
\_ I've thought about this before. I decided it's very unlikely that
they have unique tickets that are tracked by a central server. If
they did that, the server would have to be able to store hundreds
of millions of unique tickets (dating back 30 years) and there would
have to be a way to instantly process transactions from about 1,000
terminals spread over a 50-mile range. Nowadays it's more-or-less
doable, but in the 1970's it would have been a huge PITA.
\_ ah yes, but they could have easily done it with well known
techniques like database duplication, local caching, database
merging, backup modems, etc.
\_ BART can't even get the machines working well enough to
print the fucking ticket values. -tom
\_ Each ticket record would probably need to store 6-8 bytes in
a unique-tickets situation. Then you need to be able to store
several hundred records at every station in the 1970's. How
did a meg of disk cost in 1975? Like I said, it would have
been possible, but huge pain for marginal benefit.
\_ The amount of money is encoded in each card. It used to be printed
in human readble form on the card every time it was used as well
(not sure if this is still the case). The start point of your
journey is also encoded so that when you exit it knows how much
to deduct.
\_ It still is printed, BART is just really bad about changing the
toner ribbons in the turnstiles.
\_ 1) This is true, they do need to replace the toner cartridges
more frequently, and 2) your ticket is supposed to have the
amount remaining printed on it _when you exit BART_. Many ppl
think the amount is written when you buy your ticket or enter
BART, but that's not the case.
\_ It IS printed (fairly reliably) when you buy your ticket.
It gets printed sideways next to the mag-strip.
\_ I remember my dad (who worked at BART as a techie since 1972)
telling me of a fraudulent cards they came across in the 80s.
they were made out of index card stock w/ VHS tape glued down
for the magnetic strip. but if you're interested in tech politics
ignore the ticketing system and try to find out about hte train control
system and the wayside communications. what a mess! |
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| tinyurl.com/6su5r -> www.smartcardalliance.org/alliance_activities/Contactless_Technology_report.cfm Executive Summary Contactless cards are increasingly accepted as the credential of choice for controlling physical access. They are both robust and flexible, giving security professionals the ability to reduce maintenance costs, improve employee productivity and increase security. Contactless smart cards offer advantages to both the organization issuing the card and the cardholder. The issuing organization can support multiple applications on a single card, consolidating an appropriate mix of technologies and supporting a variety of security policies for different situations. Applications such as logical access to computer networks, electronic payment, electronic ticketing and transit can be combined with physical access to offer a multi-application and multi-technology ID credential. The issuer can also record and update appropriate privileges from a single central location. The organization as a whole incurs lower maintenance costs over the system life, due to the elimination of mechanical components and reader resistance to vandalism and harsh environmental conditions. With hybrid and dual-interface cards, issuers can also implement systems that benefit from multiple card technologies. Three Primary Contactless Technologies Support Physical Access Control Applications There are three primary contactless technologies considered for physical access control applications: 125 kHz, ISO 14443, and ISO 15693 technologies. The back-end system then determines the rights and privileges associated with that card. Contactless smart card technology is based on ISO 14443 and ISO 15693 standards. Cards that comply with these standards are intelligent, read/write devices capable of storing different kinds of data and operating at different ranges. Standards-based contactless smart cards can authenticate a person's identity, determine the appropriate level of access, and admit the cardholder to a facility, all from data stored on the card. These cards can include additional authentication factors (such as biometric templates or PINs) and other card technologies, including a contact smart card chip, to satisfy the requirements of legacy applications or applications for which a different technology is more appropriate. Cards complying with these standards are developed commercially and have an established market presence. Multiple vendors are capable of supplying the standards-based components necessary to implement a contactless physical access system, providing buyers with interoperable equipment and technology at a competitive cost. Contactless Smart Cards Offer Application Flexibility Standards-based contactless smart cards offer organizations the flexibility to select appropriate technologies driven by business requirements, rather than implementation constraints. This allows organizations to implement and enforce a wide range of security policies by deploying a system best suited to the application. Smart card technology - both contact and contactless - provides a flexible platform that can address both current and future needs. Multi-technology, hybrid and dual-interface cards provide additional flexibility to help with migration from existing systems and incorporate multiple technologies appropriate for different applications. Additionally, implementation considerations, such as the impact on the organization, cost, and the effect on the user population, are more effectively addressed. About This Report This report was developed by the Smart Card Alliance to describe how contactless smart cards are used for physical access. The report focuses on providing a basic tutorial of physical access system operation and an overview of the three primary contactless technologies in use today for physical access control. The report does not attempt to fully discuss contact smart card technology or applications other than physical access. The paper provides answers to commonly asked questions about contactless technology, such as: * Why consider contactless technology for physical access? Smart Card Alliance members can access all Smart Card Alliance reports at no charge. Smart Card Alliance members can access all Smart Card Alliance reports and conference proceedings at no charge. |
| oea.larc.nasa.gov/PAIS/Rendezvous.html NASA facts online banner December 1992 NF175 The Rendezvous That Was Almost Missed: Lunar Orbit Rendezvous and the Apollo Program In the opinion of many space historians, NASA Langley's most important contribution to the Apollo Program was its development of the lunar-orbit rendezvous (LOR) concept. The brainchild of a few true believers at Langley, LOR's basic premise was to fire an assembly of three spacecraft into Earth orbit on top of a single powerful rocket. Lunar module during rendezvous Pictured is the Apollo lunar module during rendezvous in lunar orbit with the command module. If rendezvous around the moon failed, the astronauts would have been too far away to have been saved. The large dark-colored area in the background is Smith's Sea. Apollo 11 crew portrait Astronauts Edwin "Buzz" Aldrin, Neil A Armstrong and Michael Collins after their selection to become the prime crew of the Apollo 11 landing mission. More than twenty years have passed since July 20, 1969, when the lunar module "Eagle" with Apollo 11 astronauts Neil Armstrong and Buzz Aldrin aboard gingerly made its way down to the Sea of Tranquility, landing men on the moon for the first time. Thousands of people and organizations in many different places played key roles in this "giant leap for mankind." As President Kennedy stated in the May 1961 speech to Congress in which he announced the nation's commitment to the lunar challenge, "It will not be one man going to the moon-it will be an entire nation. NASA Langley helped to establish many of the basic fundamentals and mission concepts central to the success of the Apollo program. In the laboratory's unique complex of wind tunnels, researchers studied the aerodynamic integrity of the Saturn-Apollo launch configuration and the problem of aerodynamic heating during the reentry of the Apollo command module into the Earth's atmosphere. Langley staff members and test facilities also played a major role in the training programs necessary to prepare NASA's astronauts for landing on the moon and moving around on its surface. In the opinion of many space historians, however, Langley's most important contribution to Apollo was its development of the lunar-orbit rendezvous concept. President John F Kennedy's decision in 1961 to land a man on the moon "before the decade is out" meant that NASA had to move quickly to find the best method of accomplishing the journey. NASA gave serious consideration to three options: Initially, direct ascent; then, Earth-orbit rendezvous (EOR), and, finally, a darkhorse candidate, lunar-orbit rendezvous (LOR). Direct ascent was basically the method that had been pictured in science fiction novels and Hollywood movies. A massive rocket the size of a battleship would be fired directly to the moon, land and then blast off for home directly from the lunar surface. The trip would be like that of a chartered bus, moving from point A to point B and back to A again in one brute of a vehicle. Strong feelings existed within NASA in favor of direct ascent, largely because it meant the development of a proposed giant booster named the Nova. After the engineers made their calculations, however, NASA realized that any single big rocket that had to carry and lift all the fuel necessary for leaving the Earth's gravity, braking against the moon's gravity as well as leaving it, and braking back down into the Earth's gravity again, was clearly not a realistic option-especially if the mission was to be accomplished anywhere close to President Kennedy's timetable. The development of a rocket that mammoth would just take too long, and the expense would be enormous. Saturn-Apollo wind tunnel testing Extensive research into the aerodynamic forces affecting the Saturn-Apollo launch configuration was performed in Langley wind tunnel. Here, researchers study the effects of wind on the Saturn V and escape tower. The demise of direct ascent led to a scrupulous evaluation of the second option: Earth-orbit rendezvous. The main idea of EOR was to launch two pieces into space independently using advanced Saturn rockets that were then in development; assemble, fuel, and detach a lunar mission vehicle from the modules that had joined up; and then proceed with that bolstered ship, exactly as in the direct flight mode, to the moon and back to Earth orbit. The advantage of EOR was that it required a pair of less powerful rockets that were already nearing the end of their development. EOR enjoyed strong support inside of NASA, especially among those who recognized that selection of EOR as the mode for the Apollo mission would require the virtual construction of a space station, a platform in Earth orbit that could have many other uses, scientific and otherwise, beyond Apollo. Wernher Von Braun and his associates at NASA's Marshall Space Flight Center in Huntsville, Alabama, favored EOR. In the end NASA selected neither of the first two options: instead, it selected the third: lunar-orbit rendezvous. The brainchild of a few true believers at the Langley Research Center who had been experimenting with the idea since 1959, the basic premise of LOR was to fire an assembly of three spacecraft into Earth orbit on top of a single powerful (three-stage) rocket. This assembly included: One, a mother ship, or command module; two, a service module containing the fuel cells, attitude control system and main propulsion system; Once in Earth orbit, the last stage of the rocket would fire, boosting the Apollo spacecraft with its crew of three men in to its flight trajectory to the moon. Reaching lunar orbit, two of the crew members would don space suits and climb into the lunar excursion module (LEM), detach it from the mother ship, and take it down to the lunar surface. The third crew member would remain in the command module, maintaining a lonely vigil in lunar orbit. If all went well, the top half of the LEM would rocket back up, using the ascent engine provided, and re-dock with the command module. The lander would then be discarded into the vast darkness of space or crashed onto the moon (as was done in later Apollo missions for seismic experiments), and the three astronauts in their command ship would head for home. Direct ascent, EOR, LOR diagrams President John F Kennedy's decision in 1961 to land a man on the moon 'before the decade is out' meant that NASA had to move quickly to find the best method of accomplishing the journey. NASA gave serious consideration to three options: initially, direct ascent; and, finally, a darkhorse candidate, lunar-orbit rendezvous (LOR). Although the basics of the LOR concept had been expressed as early as 1923 by German rocket pioneer Herman Oberth, no one had recognized the fundamental significance of LOR until two separate groups of Langley researchers in 1959, not long after Sputnik and the creation of NASA, quietly began to think about the potential of LOR for the budding American space program. One of these groups was the Lunar Mission Steering Group headed by Clinton E Brown, head of the Theoretical Mechanics Division. John C Houbolt, then the assistant chief of the Dynamics Load Division. Brainstorming by these two Langley groups, done at first independently, led to an intensive analysis of what were then thought to be two distinct subjects: one, the mechanics of a moon trip; and, two, the role of rendezvous in the operations of an Earth-orbiting space station. The idea of putting the two analyses together then led a few creative minds within the Langley study groups to consider the advantages of LOR for a manned lunar mission. Apollo 11 launch The basic premise of LOR was to fire an assembly of three spacecraft into Earth orbit on top of a single powerful rocket (the Saturn V). With the Apollo spacecraft, the Saturn V stood 363 feet tall. Pictured is the launch of Apollo 11, the first mission to land men on the moon, on July 16, 1969. The main benefit, according to Michael's unpublished 1959 paper, was the weight advantage of a small lunar lander needing less fuel. The chief problems were the "complications involved in requiring a rendezvous with the components left in the parking orbit." In Decem... |