Slashdot Mirror

An anonymous reader quotes a report from Gizmodo: The researchers, which include engineers from Rutgers University-New Brunswick, Indiana University-Purdue University Indianapolis (IUPUI), and Binghamton University, published a study this month detailing a method in which common wifi can be used to easily and efficiently identify weapons, bombs, and explosive chemicals in public spaces that don't typically have affordable screening options. The researchers' system uses channel state information (CSI) from run-of-the-mill wifi. It can first identify whether there are dangerous objects in baggage without having to physically rifle through it. It then determines what the material is and what the risk level is. The researchers tested the detection system using 15 different objects across three categories -- metal, liquid, and non-dangerous -- as well as with six bags and boxes across three categories -- backpack or handbag, cardboard box, and a thick plastic bag.

The findings were pretty impressive. According to the researchers, their system is 99 percent accurate when it comes to identifying dangerous and non-dangerous objects. It is 97 percent accurate when determining whether the dangerous object is metal or liquid, the study says. When it comes to detecting suspicious objects in various bags, the system was over 95 percent accurate. The researchers state in the paper that their detection system only needs a wifi device with two to three antennas, and can run on existing networks.

An anonymous reader quotes a report from Bleeping Computer: Rutgers engineers have created a new authentication system called VibWrite. The system relies on placing an inexpensive vibration motor and receiver on a solid surface, such as wood, metal, plastic, glass, etc.. The motor sends vibrations to the receiver. When the user touches the surface with one of his fingers, the vibration waves are modified to create a unique signature per user and per finger. Rutgers researchers say that VibWrite is more secure when users are asked to draw a pattern or enter a code on a PIN pad drawn on the solid surface. This also generates a unique fingerprint, but far more complex than just touching the surface with one finger. During two tests, VibWrite verified users with a 95% accuracy and a 3% false positive rate. The only problem researchers encountered in the live trials was that some users had to draw the pattern or enter the PIN number several times before they passed the VibWrite authentication test. Besides improvements to the accuracy with which VibWrite can detect finger vibrations, researchers also plan to look into how VibWrite will behave in outdoor environments to account for varying temperatures, humidity, winds, wetness, dust, dirt, and other conditions. This new novel user authentication system is described in full in a research paper entitled "VibWrite: Towards Finger-input Authentication on Ubiquitous Surfaces via Physical Vibration."

Chipmunk100 writes Most of the concerns about climate change have focused on the amount of greenhouse gases that have been released into the atmosphere. Researchers have found that circulation of the ocean plays an equally important role in regulating the earth's climate. The study results were published the journal Science (abstract. "Our study suggests that changes in the storage of heat in the deep ocean could be as important to climate change as other hypotheses – tectonic activity or a drop in the carbon dioxide level – and likely led to one of the major climate transitions of the past 30 million years," said one of the authors."

TMB writes Al Jazeera reports on a Rutgers study about e-voting in New Jersey after Superstorm Sandy, and it is damning. It concludes that the middle of a natural disaster is the last time to try switching to a new voting method, especially one rife with such problems as e-voting. The table of contents includes such section headings as "Internet voting is not safe, should not be made legal, and should never be incorporated into emergency measures."

Daniel_Stuckey writes "It's no secret that apps like maps or local weather know your current location, and you're probably cool with that because you want to use the handy services they provide in exchange. But chances are there are many other apps on your phone, anything from dictionaries to games, that are also geolocating your every move without your knowledge or permission. Now researchers are developing a new app to police these smartphone spies, by tracking which apps are secretly tracking you, and warning you about it. Before your eyes glaze over at the mention of yet another privacy tool, it's worth noting that this new app is the first to be able to provide this line of defense between snooping apps and smartphone users for Android phones. Android's operating system is engineered not to allow apps to access information about other apps. But a team at Rutgers University found a way around that, by leveraging a function of Android's API to send a signal whenever an app requests location information from the operating system. MIT Technology Review reported on the research today."

Hugh Pickens writes "She was at sea for 221 days, alone, often in dangerous places, and usually out of touch. Most of the time she was out of contact underwater, moving slowly up and down to depths of 600 feet, safe from ships, nets, and storms. Her predecessor had disappeared on a similar trip, probably killed by a shark. 'She was a hero,' says Rutgers University oceanographer Scott Glenn after retrieving Scarlet Knight, the 7-foot-9-inch submersible robot from the stormy Atlantic off western Spain. An engineer working for the company that made the submersible said, 'We think this will just be a precursor, like Lindbergh's trip across the Atlantic. In a decade we think it will be commonplace to have roving fleets of these gliders making transoceanic trips.' The people responsible for building, funding, and flying Scarlet hope the end of the robot's successful voyage will mark a new beginning in ocean and climate research. From its position at each surfacing — when the glider surfaced and called home via an Iridium telephone parked in its tail — researchers could calculate the net effect of currents deep and shallow. After surface currents were measured, the scientists could then make inferences about what was happening deeper in the water column. Scarlet called home to upload data to researchers three times a day. 'When we have hundreds of them, or thousands of them, it will revolutionize how we can observe the oceans,' says Jerry L. Miller, a senior policy analyst at the White House Office of Science and Technology Policy, who accompanied the research team to Spain."

RUCOOL writes "Rutgers University students and staff launched a Slocum glider AUV in an attempt to be the first such vehicle to cross the Atlantic Ocean. Progress so far is good, but it will be a long 6- to 9-month journey. Status as well as other information can be tracked here. Media links can be found in the lower left section of page, among images, and storyline blogs." And Google Earth fans can track the vehicle's progress, too.

RUCOOL writes "Rutgers University students and staff launched a Slocum glider AUV in an attempt to be the first such vehicle to cross the Atlantic Ocean. Progress so far is good, but it will be a long 6- to 9-month journey. Status as well as other information can be tracked here. Media links can be found in the lower left section of page, among images, and storyline blogs." And Google Earth fans can track the vehicle's progress, too.

RUCOOL writes "Rutgers University students and staff launched a Slocum glider AUV in an attempt to be the first such vehicle to cross the Atlantic Ocean. Progress so far is good, but it will be a long 6- to 9-month journey. Status as well as other information can be tracked here. Media links can be found in the lower left section of page, among images, and storyline blogs." And Google Earth fans can track the vehicle's progress, too.

seattle-pk notes a story in the Seattle Post-Intelligencer about the apparent protective effects of caffeine against skin cancer. "For some years, studies have hinted at the possibility that caffeine can reduce the risk of some cancers. Now, new work by scientists at the University of Washington and Rutgers University may have unlocked the biochemical secrets behind caffeine's cancer-fighting ability. Studies at Rutgers (PDF) have shown that caffeine applied to the skin reverses ultraviolet-induced damage and reduces skin cancer."

BuzzSkyline writes "The world's smallest robotic hand has been built by Yen-Wen Lu and Chang-Jin "CJ" Kim at UCLA's Mechanical and Aerospace Engineering Department. The microhand can make a fist that can grasp objects smaller than a millimeter across. Check out the freaky video on the researchers' website of the microhand grabbing a blob that looks like a fish egg. The tiny hand is made of inert materials, making it ideal for handling gooey biological samples. Lu and Kim describe their microhand in a paper published October 16 in the journal Applied Physics Letters."

jgaynor writes "The Firefox team took another step towards version 1.5 this morning as it made public release candidate 1 of it's popular browser. Users running 1.5 beta should have already received notice via an automated update dialogue box. New features include improved Pop-up blocking, enhanced automated update, better OS X support and faster back and forward page navigation buttons. A full list of features can be found in the release notes as well as the downloaded page." My copy is 24 seconds away from downloaded ;)

jgaynor writes "Citing user requests to coalesce its disparate services, Google today released its new personalized homepage service. It allows you to arrange your Gmail, Google News, Google Maps driving directions, weather and a few select news services (including Slashdot) on a single page. Future plans include Universal RSS support. Clearly a shot at existing services like My Yahoo."

tri44id writes "Several blogs have noted an Austrian team that has built a model train set that is a primitive computer. I have to point out, though, that it's actually only a Finite State Machine, like a pocket calculator, not a general-purpose device. Their plan for a general purpose layout is for an infinite-state machine, not a FSM+tape that Turing envisioned in his original paper. Turing took the concept a further step, by presenting a Universal Turing Machine that embodies a special set of states and transitions that allows its tape to be programmable to emulate any other TM. Do Slashdot readers know of any mechanical implementations of a truly Universal Turing Machine? (Danny Hillis' famous tinkertoy tic-tac-toe machine has neither infinite tape nor programmability, and is thus yet another FSM. It shouldn't be hard to elaborate the Austrian model train FSM to use a series of cars carrying movable magnets to represent Turing's tape cells writable with different symbols, and thus become a true TM or even UTM."

neutron_p writes "Every Christmas, calculations circulate that cast doubt as to whether Santa Claus could possibly deliver gifts to all the world's good children - and still remain within the laws of physics. To deliver gifts to all who deserve them, they assert, Santa would need to move so fast that he would vaporise due to air resistance, be torn to pieces by gravitational forces or suffer other terrible fates we wouldn't wish for Santa Claus. Now a team of four top researchers looked into the case and concluded: Santa can do the job and Christmas is saved! They concluded that Santa has an ion-shield of charged particles, held together by a magnetic field to solve the heat problem and he probably travels in more than four dimensions." jgaynor writes "Inspired by an old slashdot article , I decided this year to create a 'christmas lights frontend' to our Network Management System. It came out well and has had a definite impact on response times. Videos of the results are here: WMV, AVI, REAL." Mrs. Claus writes "The NORAD Santa Tracker is up and running and ready to track the Big Guy on Christmas Eve. They've got photos of 50 years of catching Santa in the act." And if you didn't listen to the Blizzard Christmas tale we mentioned in the previous post, you're missing out.

neutron_p writes "Every Christmas, calculations circulate that cast doubt as to whether Santa Claus could possibly deliver gifts to all the world's good children - and still remain within the laws of physics. To deliver gifts to all who deserve them, they assert, Santa would need to move so fast that he would vaporise due to air resistance, be torn to pieces by gravitational forces or suffer other terrible fates we wouldn't wish for Santa Claus. Now a team of four top researchers looked into the case and concluded: Santa can do the job and Christmas is saved! They concluded that Santa has an ion-shield of charged particles, held together by a magnetic field to solve the heat problem and he probably travels in more than four dimensions." jgaynor writes "Inspired by an old slashdot article , I decided this year to create a 'christmas lights frontend' to our Network Management System. It came out well and has had a definite impact on response times. Videos of the results are here: WMV, AVI, REAL." Mrs. Claus writes "The NORAD Santa Tracker is up and running and ready to track the Big Guy on Christmas Eve. They've got photos of 50 years of catching Santa in the act." And if you didn't listen to the Blizzard Christmas tale we mentioned in the previous post, you're missing out.

neutron_p writes "Every Christmas, calculations circulate that cast doubt as to whether Santa Claus could possibly deliver gifts to all the world's good children - and still remain within the laws of physics. To deliver gifts to all who deserve them, they assert, Santa would need to move so fast that he would vaporise due to air resistance, be torn to pieces by gravitational forces or suffer other terrible fates we wouldn't wish for Santa Claus. Now a team of four top researchers looked into the case and concluded: Santa can do the job and Christmas is saved! They concluded that Santa has an ion-shield of charged particles, held together by a magnetic field to solve the heat problem and he probably travels in more than four dimensions." jgaynor writes "Inspired by an old slashdot article , I decided this year to create a 'christmas lights frontend' to our Network Management System. It came out well and has had a definite impact on response times. Videos of the results are here: WMV, AVI, REAL." Mrs. Claus writes "The NORAD Santa Tracker is up and running and ready to track the Big Guy on Christmas Eve. They've got photos of 50 years of catching Santa in the act." And if you didn't listen to the Blizzard Christmas tale we mentioned in the previous post, you're missing out.

neutron_p writes "Every Christmas, calculations circulate that cast doubt as to whether Santa Claus could possibly deliver gifts to all the world's good children - and still remain within the laws of physics. To deliver gifts to all who deserve them, they assert, Santa would need to move so fast that he would vaporise due to air resistance, be torn to pieces by gravitational forces or suffer other terrible fates we wouldn't wish for Santa Claus. Now a team of four top researchers looked into the case and concluded: Santa can do the job and Christmas is saved! They concluded that Santa has an ion-shield of charged particles, held together by a magnetic field to solve the heat problem and he probably travels in more than four dimensions." jgaynor writes "Inspired by an old slashdot article , I decided this year to create a 'christmas lights frontend' to our Network Management System. It came out well and has had a definite impact on response times. Videos of the results are here: WMV, AVI, REAL." Mrs. Claus writes "The NORAD Santa Tracker is up and running and ready to track the Big Guy on Christmas Eve. They've got photos of 50 years of catching Santa in the act." And if you didn't listen to the Blizzard Christmas tale we mentioned in the previous post, you're missing out.

neutron_p writes "Every Christmas, calculations circulate that cast doubt as to whether Santa Claus could possibly deliver gifts to all the world's good children - and still remain within the laws of physics. To deliver gifts to all who deserve them, they assert, Santa would need to move so fast that he would vaporise due to air resistance, be torn to pieces by gravitational forces or suffer other terrible fates we wouldn't wish for Santa Claus. Now a team of four top researchers looked into the case and concluded: Santa can do the job and Christmas is saved! They concluded that Santa has an ion-shield of charged particles, held together by a magnetic field to solve the heat problem and he probably travels in more than four dimensions." jgaynor writes "Inspired by an old slashdot article , I decided this year to create a 'christmas lights frontend' to our Network Management System. It came out well and has had a definite impact on response times. Videos of the results are here: WMV, AVI, REAL." Mrs. Claus writes "The NORAD Santa Tracker is up and running and ready to track the Big Guy on Christmas Eve. They've got photos of 50 years of catching Santa in the act." And if you didn't listen to the Blizzard Christmas tale we mentioned in the previous post, you're missing out.

Several readers sent in notes about an interesting signal discovered by SETI. No real evidence of Someone Out There, but not fully explainable either. Another reader submits a blurb suggesting that aliens should send spacemail, not signals: "Rutgers electrical engineering professor, Christopher Rose, has an article on Nature magazine's cover today describing the most efficient way for our civilization to be discovered by aliens. On this question of better to 'write or radiate', his conclusions: better not to send radio transmission, when physical media like DNA on an asteroid can declare a terrestrial presence. Similar to what motivated Voyager scientists to attach a plaque for the outbound trip. Rose has some great information payload sizes as examples (like the entire information equivalent for our global genome fitting on a 100 pound laptop!)."

Several readers sent in notes about an interesting signal discovered by SETI. No real evidence of Someone Out There, but not fully explainable either. Another reader submits a blurb suggesting that aliens should send spacemail, not signals: "Rutgers electrical engineering professor, Christopher Rose, has an article on Nature magazine's cover today describing the most efficient way for our civilization to be discovered by aliens. On this question of better to 'write or radiate', his conclusions: better not to send radio transmission, when physical media like DNA on an asteroid can declare a terrestrial presence. Similar to what motivated Voyager scientists to attach a plaque for the outbound trip. Rose has some great information payload sizes as examples (like the entire information equivalent for our global genome fitting on a 100 pound laptop!)."

lordbry asks: "I am a Windows admin for a major university in a business computing area (if we have problems, people might not get paid). We have a Windows NT Domain, and are planning to migrate to Active Directory. One of my co-workers is pushing for doing this under Windows 2003. I, however, feel that (as with any M$ product) we should not even consider using 2003 for production anything until there is an SP 2 or 3, and that we should go with AD under Windows 2000. Does anyone have any advice, arguments, or horror stories that could help me make my case to the rest of my group, all of whom are somewhere in the middle? Does anyone think that 2003 is the way to go?"

Chirag Mehta writes "I just released a freeware service called BotBlock (barebones demo) that lets site owners copy/paste a few lines of PHP code and insert a CAPTCHA image-verification system into any web form. The amount of form spamming by bots is on a rise. While remedies exist for MT blogs, a more efficient solution is to use image-verification or text-identification. Used for a while by sites like Yahoo! (scroll to bottom), Hotmail and patented in 2001 by AltaVista, CAPTCHAs are now being used more widely. PARC also came up with two algorithms Baffletext and Pessimal Print. The technology always existed, but until now required the site owners to install image libraries and understand how to generate images that cannot be OCR'ed. With BotBlock it is like inserting a page counter."

carrowood writes "A survey was conducted questioning open source developers from both large and small projects concerning their quality assurance practices. A research paper based on the survey result was just published in the Journal of Systems and Software. Some comparisions between QA practices of open vs closed source projects are made with some interesting observations. While on the whole it looks like open source QA can be as good as that in traditional software development, there were a few areas pointed out where the open source community does not do so well, such as regression testing and setting release dates. A thought provoking read."

edpin writes "CNN is reporting this new mouse that works without a surface. You hold the device in your hand and tilt it to where on screen you want it to go. It uses a similar technique to "rock and scroll" developed by Compaq (now HP) a while ago."

kenthorvath writes "This guy and his friend built their own cyclotron, capable of 1 MeV protons using spare parts and surplus science equipment. Anyone else happen to have a 4600 lb. magnet lying around?"

kenthorvath writes "This guy and his friend built their own cyclotron, capable of 1 MeV protons using spare parts and surplus science equipment. Anyone else happen to have a 4600 lb. magnet lying around?"

dlupyan writes: "A federal appeals court said Monday that Napster Inc. may not resume its free online file-swapping service."

mshiltonj writes: "Wired is reporting that keyboard sniffing can be used to catch "mobsters." I feel safer already. You can read the ruling. Here's a snippet: "This case presents an interesting issue of first impression dealing with the ever-present tension between individual privacy and liberty rights and law enforcement's use of new and advanced technology to vigorously investigate criminal activity. It appears that no district court in the country has addressed a similar issue. Of course, the matter takes on added importance in light of recent events and potential national security implications." Translation: Don't deny us this tool or you'll be blamed for us not catching terrorists." See also an Infoworld article. We have several previous stories on the Scarfo case.

A little while ago you asked Forth (and now colorForth) originator Chuck Moore about his languages, the multi-core chips he's been designing, and the future of computer languages -- now he's gotten back with answers well worth reading, from how to allocate computing resources on chips and in programs, to what sort of (color) vision it takes to program effectively. Thanks, Chuck!

FFP, Combinator Calculus and Parallel Forth
by Baldrson

In his 1977 Turing Lecture, John Backus challenged computists to break free of what he called "the von Neumann bottleneck". One of the offshoots of that challenge was work on massive parallelism based on combinator calculus a branch of mathematics that is far closer to Forth's formalism than parameter list systems (which are more or less lambda calculus derivatives).

The prolific Forth afficionado Philip Koopman did some work on combinator reduction related to Forth but seems not to have followed through with implementations that realize the potential for massive parallelism that were pursued in the early 1980s by adherents of Backus's Formal Functional Programming paradigm. Given recent advances in hierarchical grammar compression algorithms, such as SEQUITUR, that are one step away from producing combinator programs as their output, and your own statements that Forth programming consists largely of compressing idiomatic sequences, it seems Backus's original challenge to create massively parallel Formal Functional Programming machines in hardware are near realization with your new chips -- lacking only some mapping of the early work on combinator reduction machines.

It is almost certainly the case you are aware of the relationship between combinator reduction machines and Forth machines -- and of Backus's challenge. What have you been doing toward the end of unifying these two branches of endeavor so that the software engineering advantages sought by Backus are actualized by Forth machines of your recent designs?

Chuck Moore: What can I say? Backus did not mention Forth in his lecture. He probably didn't know of it then. Yet Forth addresses many of his criticisms of conventional languages.

He thinks a language needs or benefits from a formal specification. I grew up worshiping Principia Mathematica 'till I learned how Goedel refuted it. The result is that I distrust formal representations. For example, the ANSII Forth standard does not describe Forth, but a language with the same name.

Yes, I am struck by the duality between Lisp and Lambda Calculus vs. Forth and postfix. But I am not impressed by the productivity of functional languages. Even as research tools, they have failed to live up to their promise. By that I mean to do something with computers that I couldn't do more easily in Forth.

I designed the memory for the c18 to occupy the same area as the processor. This means small, fast and smart. c18 can respond to a bus request by fetching from its memory, accessing off-chip or performing a calculation. The 25x avoids the von Neumann bottleneck by making up to 27 memory accesses at the same time (2 off-chip). And its multiple buses do not substitute a network bottleneck for a memory one.

Standard code will be in the ROM of each computer. How this is customized in RAM and the computers assigned tasks is left to the ingenuity of the programmer, not a compiler. Automatically generated or factored code has never impressed me. Nor has automatic place and route for circuit boards or silicon. They are both an order-of-magnitude from human performance. Because humans understand the problem, judge the results and cheat as required.

Marginalizing of the blind
by Medievalist

When I built my first Internet node, the web did not yet exist, and one of the amazing things about the Internet was how friendly it was to the blind.

Now, with some computer experts estimating that over 50% of the Internet is incomprehensible to braille interfaces, and most computer operating systems devolving to caveman interfaces ("point at the pretty pictures and grunt") we seem to be ready to take the next step - disenfranchising the merely color-blind.

I realize that colorforth is not inherently discriminatory, in that there are a great many other languages that can be used to do the same work. The web is also not inherently discriminatory, because it does not force site designers to design pages as stupidly as, for example, Hewlett-Packard.

Would you care to comment on the situation, speaking as a tool designer? How would you feel if a talented programmer were unable to get a job due to a requirement for colored sight?

CM: I'm amazed at how effective blind programmers can be. I rely so strongly upon seeing the code that it's hard to imagine listening to it. Yet I know it can be done. Not being color-blind, it's hard to appreciate the degree of information loss. But it's less than being blind.

My goal is to develop tools that augment my abilities. If others can use them, fine. It would be foolish to lose an opportunity to explore or excel just to conform to some equalitarian philosophy. Too often our culture seeks the lowest common denominator.

20-20 vision is required for fighter pilots. I have no qualms about requiring color vision for programmers. Everyone does not need to be a programmer.

But in fact, color is merely a property of words that helps to distinguish them. As is intensity, size, font, volume and tone. I'm sure colorForth will be translated into these other representations. I, myself, will be exploring spoken colorForth. (As soon as I can decipher PC sound cards.)

Massively Parallel Computing
by PureFiction

The 25X system reminded me of IBM's Blue Gene computer, where a large number of inexpensive CPU cores are placed on a single chip.

The biggest problem in dealing with a large number of small cores lies in the programming. I.e. how do you design and code a program that can utilize a thousand cores efficiently for some kind of operation? This goes beyond multi-threading into an entirely different kind of program organization and execution.

Do you see Forth (or future extensions to Forth) as a solution to this kind of problem? Does 25X dream of scaling to the magnitude that IBM envisions for Blue Gene? Do you think massively parallel computing with inexpensive, expendable cores clustered on cheap dies will hit the desktop or power-user market, or forever be constrained to research?

CM: Forth is a massively pragmatic language: do whatever you can to solve a problem. Its strength is in the ease of violating whatever rules it has. The 25x is similarly pragmatic. I don't know how to program it yet, but I'm confident I can. It's just another level of factoring.

The parallelism provided by the 25x has a different slant from other parallel architectures. The computers are not identical. I expect many will have different ROM and different interface to the real world. This asymmetry is a powerful clue as to how applications will be factored.

A 10x10 array of 25x chips is an easy board to build. At 50 Watts, it needs as much power as a notebook. That's 2500 computers providing 6M Mips. I can't imagine programming them any other way than Forth.

The advantage of Forth in this kind of context is that it scales. Forth is the machine language, Forth is the high-level language, Forth is the task-control language, Forth is the supervisory language. Each of these has a different vocabulary, but they share syntax, compiler and programmer skills.

Back to the array of 25x chips. Each chip could be on a vertical and horizontal serial bus with 10 others. A half-duplex bus requires a computer to manage, so that accounts for 200 computers. Now whatever the application, data must be provided. Say 1GHz Ethernet. Data (and program) is received, distributed and crunched. The assignment and coding of computers follows the data flow. Results are routed back to Ethernet, or displayed or whatever. It's a nice programming problem, well within the ability of a human to organize.

Will this ever reach the mass market? I don't know.

The direction of 25x Microcomputer...
by Midnight Ryder

The 25x concept looks like it could really a damned interesting idea. But one of the questions in my mind is where you want to head with it? Is this something that is to be used for very specialized research and scientific applications, or is this something that you envision for a general 'desktop' computer for normal people eventually?

Secondly, if you are considering the 25x for a desktop machine that would be accessible by people that aren't full-time geeks, what about software? Forth is a lost development art for many people (It's probably been 10 years since I even looked at any Forth code) and porting current C and C++ application would be impossible - or would it? Is there a potential way to minimize the 'pain' of completely re-writing a C++ app to colorForth for the 25x machines, which could help to speed adoption of a platform?

CM: At this stage the 25x is a solution looking for a problem. It's an infinite supply of free Mips. There's no obligation to use them all, or even very many. But they can effectively be used to eliminate hardware. To bit-bang what would otherwise need a controller. So if you want video or audio or radio or ...

The first applications will doubtless be embedded. These offer greater volume, less software and less market resistance than a general-purpose computer. I see 25x reaching the desktop as dedicated appliances rather than universal golems.

I'm not interested in recoding C applications. My experience indicates that most applications are hardware-dependent. The 25x is as large a change in the hardware environment as I can imagine. This changes the program so much it might as well be rethought and recoded. The most efficient way to do that is Forth.

Forth is a simple, interactive language. Its learning curve is steep with a long tail. You can be productive in a day/week. This depends only on how long it takes to memorize pre-existing words. Good documentation and management helps mightily. I'd rather train programmers than fight code translators.

That said, there are those who look at the mountain of existing applications and want to mine it. C to Forth translators exist and with some pre/post editing could produce code for the c18 core. How to distribute the application among 25 tiny computers would be a good thesis.

Quick question
by jd

I have often conjectured that multi-threaded processors (ie: processors that can store multiple sets of internal states, and switch between them) could be useful, as the bottleneck moves from the processor core to communications and dragging stuff out of memory.

(If you could microcode the "instruction set", all the better. A parallel processor array can become an entire Object Oriented program, with each instance stored as a "thread" on a given processor. You could then run a program without ever touching main memory at all.)

I'm sure there are neater solutions, though, to the problems of how to make a parallel array useful, have it communicate efficiently, and yet not die from boredom with a hundred wait-states until RAM catches up.

What approach did you take, to solve these problems, and how do you see that approach changing as your parallel system & Forth language evolve?

CM: The 25x could implement a multi-thread application nicely indeed. Except that most applications expect more memory that a c18 core has. Whereupon memory remains the bottleneck.

It's important to choose problems and solutions that avoid using off-chip memory. Even so, with 25 computers to support, I expect that every memory cycle will be utilized. The computer controlling memory can be smart about priorities and about anticipating requirements. For example, it could guarantee enough access to support display computers.

And the nice thing about memory-mapped communication is that a computer need not be aware of its environment. It's an ordinary Forth program accessing data asynchronously. Delays are invisible, as is synchronization. Of course, due care is required to avoid lock-up loops.

These conjectures are fun. But in a year we'll have real applications to review. And a much better appreciation of the advantages and drawbacks of so many tiny computers.

Programming languages...
by Midnight Ryder

This one would probably require a bit more time to answer than you probably have available, but a quick rundown would be cool: Where do you see programming languages headed -vs- where do you think they SHOULD be headed?

Java, C#, and some of the other 'newer' languages seem to be a far cry from Fourth, but are languages headed (in your opinion) in the proper direction?

CM: I've been bemused with the preoccupation of new languages with text processing. I've been accused of not providing string operators in both Forth and colorForth. Indeed, I haven't because I don't use them. Editing a file to pass on to another program never struck me as productive. That's one reason I chose pre-parsed source, to break the dependence upon strings and text processors.

Languages are evolving, as evidenced by the new ones that arise. But as with natural evolution, the process is not directed. There is no goal to approach nor any reward for approaching it. But whatever progress you might perceive, I don't. New languages seem only to propose new syntax for tired semantics.

These languages are all infix. Which is extraordinarily clumsy for anything but arithmetic expressions. And even those are comfortable only because we learned them in Algebra 101. Do you remember the learning curve?

Does everyone really think that 50 years into the computer age we have hit upon the ultimate language? As more and more C code accumulates, will it ever be replaced? Are we doomed to stumble over increasingly bloated code forever? Are we expecting computers to program themselves and thus save civilization?

I'm locked in the Forth paradigm. I see it as the ideal programming language. If it had a flaw, I'd correct it. colorForth uses pre-parsed source to speed and simplify compilation. This solves a non-problem, but it's neat and worth exploring. At least it proves I haven't gone to sleep.

What about memory protection?
by jcr

From the web pages, I don't see any mention of access control.

Can this processor be used in a multi-user, general-purpose mode?

CM: If you had a chip, you'd physically control access to it. It doesn't make sense for another person to share your chip. He can get his own. Certainly an individual c18 has too little memory to multi-task. And I doubt 25 computers could run 25 tasks.

But the 25 computers can certainly perform more than one task. They have to share resources: communication buses, off-chip memory and interfaces. Access is negotiated by the computer in charge of the resource. There is no hardware protection. Memory protection can be provided by the access computer. But I prefer software that is correct by design.

Communication with other computers, via internal or external buses, is subject to the usual problems of scheduling, routing and authentication. Internally, at least, my goal is to minimize delay rather than attempt protection. I anticipate spectacular crashes while software is developed. (Have you ever crashed 2500 computers?)

Where is forth going?
by JanneM

I learned forth early on in my programming career; it was very memory and CPU efficient, something that was important on early microcomputers. It was also a great deal of fun (though far less fun to try and understand what you wrote a week earlier...). Today, even small, cheap microcontrollers are able to run fairly sophisticated programs, and it is far easier to cross-compile stuff on a 'big' machine and just drop the compiled code onto the development board.

Forth has (in my eyes) always been about small and efficient. Today, though, embedded apps are more likely to be written in C than in forth, and the "OS as part to the language" thing isn't as compelling today as it was in the eighties. Where is forth being used today, and where do you see it going in the future?

CM: Forth is being used today as it always has been. In resource-constrained applications. I think they will always exist. I'm creating some with the tiny c18 computers in the 25x. I imagine molecular computers will be limited when they first appear.

Personally, I don't mind losing a mature market that can afford abundant resources. Such applications aren't as much fun. But Forth isn't restricted to small applications. Even with huge memories and fast processors, small, reliable programs have an advantage.

The major project cost has become software, to the dismay of managers everywhere. On-time, bug-free software is the grail. Forth doesn't guarantee it, but sure makes it easier. Will this ever be convincingly demonstrated? Will management ever value results over procedures?

The currently popular language is selected by uninformed users. The only thing in favor of such democratic choice is that it's better than any other. But why would anyone want to debug 1M lines of code instead of 10K?

What's the next Big Computational Hurdle?
by DG

Now that sub-$1k computers are running in the GHz range, it seems that all the computational tasks on a common desktop system are not processor-bound.

3D, rendered-on-the-fly games get well over 30 frames per second at insanely high resolutions and levels of detail. The most bloated and poorly-written office software scrolls though huge documents and recalculates massive spreadsheets in a snap. Compiling the Linux kernel can be done in less than 5 minutes. And so on.

It seems that the limiting speed of modern computers is off the processor, in IO. What then, do you forsee coming down the pike that requires more processor power than we have today? What's the underlying goal you intend to solve with your work?

CM: Memory is cheap. I don't mind wasting memory as long as it's not full of code that has to be debugged.

Likewise, Mips are cheap. The trick is to find productive ways to waste them. A Pentium waiting for a keystroke isn't very clever.

So here's a huge pool of Mips. What can you do with them? Voice recognition comes instantly to mind. Image recognition close behind. The brain deploys substantial resources to these tasks, so I suspect a computer must.

IO is indeed a bottleneck, but not in principle. If you can't get data from the camera to the computer, combine them. Put the image recognition algorithms in the camera. Analyse, reduce, compress data at the source. Meanwhile, it helps to have multiple paths off-chip.

revolutionary
by rnd

What is the most revolutionary (i.e., it is scoffed at by those in control/power) idea in the software industry today? Explain how this idea will eventually win out and revolutionize software as we know it.

CM: Forth! But then I haven't been out looking for revolutionary ideas. I like the phrase Baldrson used above: compressing ideomatic sequences. If you do this recursively, you obtain a optimal representation. I see no way to get a more compact, clear, reliable statement of a problem/solution.

Forth clearly revolutionizes software as most know it. It could lead to efficient, reliable applications. But that won't happen. A mainstay of our economy is the employment of programmers. A winnowing by factor 100 is in no one's interest. Not the programmers, the companies, the government. To keep those programmers busy requires clumsy languages and bugs to chase.

I don't have to be glib or cynical. Those are facts of life. Society must cope with them. But I don't have to. Nor you. There are niches in which you can be creative, productive, inspired. Not everyone can be so lucky.

Forth as intermediate language
by Ed Avis

Many high-level languages compile into C code, which is then compiled with gcc or whatever. Do any use Forth instead? I understand Forth is a stack-based language: doesn't that present problems when compiling for CPUs that mostly work using registers?

CM: I remember my shock at learning that Fortran compiled into Assembler, that then had to be assembled. A language that can be translated into another is clearly unnecessary. Truely different languages cannot be translated: C into Lisp.

Forth would make a fine intermediate language. But why have an intermediate language? It introduces another layer of confusion and inefficiency between the programmer and her computer. Macros were invented to support compiling directly to machine code.

Stacks are a compiler-friendly construct. Every compiler has to use one to translate infix notation to postfix. If this stack solution has to be assigned to registers, it's an extra step. Forth uses stacks explicitly and avoids the whole subject.

Register-based CPUs have more problems than just the complexity of their compilers. Their instructions must contain register addresses, which makes them longer and programs bigger. And it is rare that every register can be used in every instruction.

Moreover registers need to be optimized. After assigning system registers, performance depends on how well the remaining registers are handled. Compilers can optimize infix expressions better than humans. But such expressions are no longer the preferred means of doing arithmetic. DSPs and super-computers integrate difference equations.

Design guidelines encourage code with many subroutine calls each with only a few arguments. This is the style Forth employs. But it plays havoc with optimization, since register usage must be resolved before each call. So apart from being unnecessary and difficult, optimization has no effect on good code.

Stanford University held a workshop last Friday - The Policy Implications of End-to-End - covering some of the policy questions cropping up which threaten the end-to-end paradigm that serves today's Internet so well. It was attended by representatives from the FCC, along with technologists, economists, lawyers and others. Here are my notes from the workshop. I'm going to try to skip describing each individual's background and resume, instead substituting a link to a biography page whenever I can. (Part two of two - part one ran yesterday.)

The final segment of the morning covered caching. The main issue centered around transparent caching, where users ask for certain content but their request is silently fulfilled by a caching proxy server instead, generally without the user having any way to detect this. The standard concept of caching has the user being presented with the same content she would otherwise have gotten from the requested site, but that need not be true - Singapore, China and Australia have all used transparent caches to censor their citizens. This can also be a security violation (are you really talking to the secure server on stupidpettoys.com, or a proxy in between? Most users won't notice the difference.). Ann Brick noted a subsidiary issue - big commercial players have the ability to pay for their sites to be cached, while individuals do not. Similar to the QoS issue, this might be used to discriminate between paying, fast, commercial sites, and sites owned by individuals or even competitors.

David Clark made the insightful observation that dollars spent on caching don't go to general network improvements -- one small piece of the network is improved by caches, but the same money spent improving the whole network could improve it for everyone. Timothy Denton concluded this segment with the characterization of transparent caching as the difference between "form follows function" and "function follows form": the mere presence of caching and the ability to interfere with content delivery in the middle of the network destroys end-to-end and creates opportunities for mischief.

In the afternoon, there were two larger sessions covering broadband and wireless Internet access. In both areas, the companies controlling these access methods have strong motivations to violate end-to-end principles.

Jerry Duvall led the broadband discussion. He presented a rather fascinating economists' view of the situation -- an economists' world being solely concerned with customers, producers and markets. Laws are necessary to enable markets -- contract law, commercial law, fraud law, and so on are needed in order for markets to function. He summoned up the ghost of Adam Smith with a brief review of capitalism: producers always conspire against the public to get more profits from them, only competition keeps them in check. Marketing, lock-in, monopolization, and predatory pricing are always used by producers. He denied that end-to-end represented any sort of a perfect competitive market, however, suggesting that customer wants cause problems -- in some cases, customers actually want bundles from a single provider, and may actually prefer non-end-to-end Internet access. From an economist's point of view, end-to-end is only a means to an end. The end in this case is creating value for the customer. If that involves end-to-end Internet access, fine. If it doesn't, still fine. The value to the customer is paramount, engineering elegance is secondary.

Duvall also suggested that many observers have a naive view of regulation. With regard to the debate over open access to cable systems, he stated that there was no easy way for regulators to "come in and fix it." Regulation implies overcoming the resistance of entrenched players, and in the case of open access to cable systems, AT&T and other cable giants have proven adept at fighting lawsuits in support of their ability to keep their systems closed.

As we've seen previously, there was discussion of the reasons why end-to-end can be violated: sometimes customers want it, but (probably more often) the wants of companies are the driving force. Duvall suggested the external value of end-to-end in fostering competition and democratic values isn't adequately valued in most considerations of the economics of broadband. That is, the cost of violating end-to-end is spread out among many users of the network, but the benefits from that action accrue mainly to individual companies -- in economic parlance, this is called externalizing costs.

Another panelist emphasized the democratic value of open systems, a recurring topic in Lessig's writings. There was a bit more discussion of bundling-as-an-aid-for-novice-users vs. bundling-as-a-way-to-lock-in-customers. Jerome Saltzer reiterated the time-tested solution for monopoly problems: separate the content from the content-carriers. Deborah Lathen, acting perhaps as devil's advocate, asked why the builder of the pipe shouldn't be allowed to monopolize it. Duvall noted that no matter what the FCC might do to regulate cable carriers, that economic theory doesn't hold much chance for relief -- any time there's a monopoly (over the cable pipe), the monopolist is going to be able to extract monopoly rents, one way or another. If regulation affects a certain aspects of the business, the monopolist will find some other way to leverage the monopoly for greater profits. The only sure remedy is eliminating the monopoly.

Further audience discussion raised the idea that the concept of "an ISP" is a odd sort of legacy brought about by the necessity to have an intermediary between the telephone network and the TCP/IP network. In the future, the concept of an ISP may change radically. A question was asked: what benefit does the public get by allowing the cable companies to monopolize access? There were no good answers.

Mark Laubach gave a good overview of the architecture of cable Internet access, referring to the DOCSIS standard, which wasn't designed with open access in mind. Laubach stated that "basic IP dialtone" -- that is, a simple TCP/IP Internet connection without frills or bundled services -- should be a consumer right, which should apply to every broadband service regardless of delivery method: cable, DSL, wireless or satellite services.

Peter Huber summarized the open-access debate as it affected phone companies. The phone companies had a 1Mhz twisted pair of copper strands that they swore up and down couldn't be shared. They were ordered to share it, and now are doing so: local and long-distance competition, shared data/voice over that tiny line, co-location at central offices, etc. Now the cable companies have a 750mhz copper wire that they claim is "impossible" to share. Huber emphasized that whatever the regulations, cable and phone companies should be treated equally. Currently there are disjointed regulations, which (depending on your viewpoint) either unduly hamper phone companies or leave cable companies unfairly unrestricted.

Further discussion brought out the case of Stockholm, Sweden. Stockholm and certain other cities have taken on the job of laying fiber-optic cable as a municipal service, similar to sewer service or water or roads. Since the municipality built the pipe to the home, there is no issue of a company attempting to monopolize the pipe, and any company which wants to offer Internet service over the pipe may do so. As a result, Stockholm residents are getting extremely fast access speeds at prices less than U.S. residents pay for cable Internet access, and customers don't have to worry about the cable monopoly steadily reducing their upstream speeds, or banning servers, or whatever other crackdown U.S. cable providers have thought of most recently. The panel then debated whether (and how) it would make sense to move the U.S. to that sort of municipal model. A panelist threw out the figure that true open access to cable pipes might require a choice of 400 ISPs. An audience member suggested that as things are currently going in the U.S., there might be a choice of five ISPs at most, hand-picked by the cable provider.

David Clark added that whatever solution is proposed, it must be an ongoing process -- since cable Internet access is certainly not going to be the final stage of bandwidth development. Finally the broadband session closed with a pithy statement that, despite claims to the contrary, content is not king -- there is, and always has been, more money in individuals talking to each other than in one-way content distribution. The question that remains is how to convince broadband providers that there is more money to be made in selling large quantities of low-profit services rather than small quantities of more profitable ones.

The day concluded with a session about wireless Internet access. Unsurprisingly, WAP was the first topic to come up: a closed, end-to-end-unfriendly, expensive protocol that is all but deceased in the market, yet still actively promoted by companies that hope to benefit from controlling wireless Internet access.

Karl Auerbach had an insightful comment about why to use plain vanilla TCP/IP instead of a bespoke wireless protocol. Similar to the argument raised by Bruce Schneier and others that using a proven crypto algorithm makes sense because there are a lot of bad protocol writers in the world, Auerbach posited that freely available TCP/IP stacks have had the bugs beaten out of them, but the average proprietary protocol hasn't. The topic shifted to the location information that is now required to be built in to mobile phones. The panel discussed the control issues inherent in different network architectures: location information could be built into the phone, and controlled by the user, or it could be built into the cell towers, and controlled by the phone company (or law enforcement, or advertisers). It looks like the second architecture will be the one that is deployed.

Yochai Benkler brought up the issue of spread spectrum changing the rules for FCC frequency allocation -- more communications may shift to frequencies where the FCC does not require licenses to broadcast. Dewayne Hendricks gave a lengthy and interesting description of how amateur radio is currently being used in a manner similar to the venerable Fidonet to pass packet data over the short-wave frequencies via a store-and-forward system. The interesting part is that Amateur Packet Radio has been around for 15 years or so. Hendricks' concept was that the first truly free network would be one composed of independent wireless spread-spectrum devices creating an ad hoc network which could not be censored or controlled by any entity whatsoever. One audience member quipped that disruptive technologies always appear to incumbents as toys.

Hendricks noted some other wireless WANs, such as one in the San Francisco Bay area using Breezecom wireless cards and antennae. (Coincidentally, Salon did a story on wireless WANs just a few days ago.) Dale Hatfield noted that Hendricks' network could be created today using licensed spectrum, and noted that the greatest danger is incumbent spectrum-holders pushing regulations which protect their investments by making it difficult for the FCC to open up or use sections of the spectrum for these innovative uses.

Towards the end, one member of the audience (and I do apologize for not catching who it was), pulled everything together by noting the convergence between end-to-end as a technological issue, open access as an economic issue, and democracy and public debate as a political issue. The idea of eliminating "gatekeepers" on the internet is important for a great many reasons, whether you look at it as a technological issue of promoting progress and innovation, or as an economic issue of fostering competition and preventing monopolies from abusing their power, or as an issue of promoting free and unrestrained speech on the communications media of the 21st century. This is certainly one of the most important issues facing the country today, but relatively few people know anything -- even a smidgeon -- about it, or at most they've read a few news reports about the AOL/Time Warner merger. I'm glad to see such a diverse and intelligent group working on the issues, and if they don't yet have all the answers, it's only because they want to get it right.

In an update on the windows refund story, BiGGO writes "Someone was quick enough to open a site about the EULA-refund trick. They are encouraging people who were forced to pay for Windows but never used it to ask for a refund on a special refund day, Feb 15th" 136 people have already joined them in the 24 hours since the site went live. Update: 01/20 07:09 by S : David Cornette contributed this Wired story on it, and elflord forwarded this ZD-Net Story.

A few have asked about getting these spiffy remotes working under Linux so I figured I'd finally have to run something, but the submissions have been piling up rather quickly. So if you have a remote mouse, this topic is for you! Here are a couple of the submissions I've received on this... Codger, asks "I have a Logitech remote control, and I'd like to use it under Linux. Does anyone know anything about this? The remote plugs into a serial port and augments the mouse pointer when on. I have software for it that runs under Windows 95, but I'd like to get it working under the 'One True OS'. Anybody have any ideas?"

And another from Nicholas Loscalzo who would like help with the following: "A couple of days ago, I picked up, for free (well, after the rebate) an Interact Web.Remote professional from OfficeMax. The thing is pretty damned cool. Serial port interface to a wide-angle IR receiver. The remote unit has a trackball, left and right "clickers" (two sets) and a keypad with 9 numerics and 9 play/stop/rewing/vol/etc keys. My question: I enjoy using my intellimouse with my main machine too much, so I don't want to set up the remote on that box (tried it on it though, it's definitely NOT a full-time use mouse, despite the advertisement.....), so I was thinking of popping it on to my linux box. Question is, has anyone written support for it yet in X (or consoles?) ? It'd be cool as hell to be able to control a bunch of functions all from remote."