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Comment Re:Very much not new (Score 1) 22 22

No, you wouldn't -- at least, not with any sensible topology.

The way it usually works is like this: You present your Wiegand card to the Wiegand reader, some magic RF resonance happens, and a stream of bits is produced on a wire.

At the other end of this wire, buried deep in the bowels of the building, is a computer (embedded or not) which verifies that your bits are the correct bits. If they are correct, it closes a relay that makes the door open, and (optionally) signals the reader to provide feedback to the user (blinking LED, sound, etc). If they are incorrect bits, it doesn't do anything with the door, and (optionally) provides feedback to that effect (in the form of a blinking LED, sound, dumping poison gas).

Getting access to the data lines at the reader does not magically equate to physical access to the building, except in Hollywood movies and horrifyingly-bad installations (whereby the insecure reader itself does the numeric verification, and/or uses its own internal relay controls the door).

IOW, you can pry the reader off of the wall and twist any wires together that you want..and nothing happens at all except perhaps a blown fuse somewhere upstream and a headache for whoever has to clean up your mess.

Comment Re: Looking more and more likely all the time... (Score 1) 478 478

Solar panels would not be very useful for constant acceleration in interstellar space. An RTG would have been a better example, but you might be missing the point. The whole point of a so called 'space drive' would be to be able to produce a continuous thrust without having to carry around large amounts of reaction mass to do so.

This drive does not appear to emit any mass. At least nothing that we are currently able to measure. And yet it somehow seems to produce thrust. Usually there is a proportional relationship between thrust and reaction mass. Of course it may simply be that we are failing to measure the form of mass/energy being emitted and that it actually does consume some new form of mass about which we have been previously unaware.

Comment Re:Some clarifiications (Score 1) 478 478

A photonic rocket does not use reaction mass, and expels massless photons

Photons have mass: inertial mass. They have momentum and it has been measured experimentally. So it is merely a quantitative difference. Not a qualitative one.

The EMdrive does not require reaction mass

This statement really needs to be qualified more with 'may/might/could'. I believe this has not yet been proven. Experiment so far simply cannot measure any form of mass being emitted. That does not mean it is not present. The absence of evidence is not evidence of absence. This experiment may have discovered a new form of matter or energy of which we have previously been unaware. All we know so far is that the apparatus appears to be generating thrust by some unknown means and that is all that can be concluded from this and of course even that is very uncertain at this point.

Comment Re: Looking more and more likely all the time... (Score 1) 478 478

>If this thing were to truly work, it would have insane implications to some basic assumptions about the universe - namely about the very laws of physics themselves.

Only if you assume that we are capable of measuring every particle that actually exists. Only if you assume that there is not some form of mass here that we simply do not know how to detect. I would consider a new sort of wave/particle, some new form of inertial mass that we do not yet know how to detect, to be more likely than a violation of the conservation of momentum. The assumption of the opacity of the container in this apparatus is also no more than an assumption. It may be transparent to an unknown particle type. Something completely unknown to current physics or just something that we haven't thought to look for yet.

If such a form of mass/energy actually exists it may be the breakthrough to space propulsion that we have all been waiting for. If this form of mass results from EM radiation it could certainly be the sort of thing that overturns the current paradigm though. But perhaps without violating something as fundamental as the conservation of momentum.

Comment Re:Blimey (Score 1) 478 478

Photons have inertial mass. They just don't have rest mass. Although has anyone ever observed a photon at rest? If the state never occurs then I'm not sure I understand the point of positing a 'rest mass' and claiming that photons wouldn't have any if they could somehow be stopped. If there is no experiment through which you can show that a photon does not have rest mass then I don't see how one can make that claim. We would just like to believe they have no rest mass because that is what is consistent with current theory.

Comment Re:ah, Tajmar eh? (Score 1) 478 478

And extreme criticism requires equally extreme credentials.

And just what are your credentials, sir? Does your criticism not require credentials? Argument from Authority is a common logical fallacy. Learn to think independently and logically and you will soon discover that authority figures are unnecessary and that credentials do not change the scientific validity of any claim. Either the evidence and experimental data are there to be observed by anyone or they are not. No one else can do your thinking for you.

Comment Re:Physics time! (Score 1) 478 478

>The EM drive creates a momentum by pushing virtual particles

By a 'virtual' particle do you mean one that does not actually exist except in our imagination? If it only exists in our imagination does that mean the thrust they impart as massless reaction mass is also a figment of our imagination? I would imagine that virtual particles would be more useful for accelerating imaginary spacecraft than real ones.

The thrust created with the experimental apparatus is simply unexplained. That is all.

Comment Re:Netflix, Amazon, Hulu (&& wtf is up wit (Score 1) 100 100

Slashdot's 3rd-party linking is now worse than even CNET, Target, Walmart, etc.

All hail our new corporate overlords. Meet the new boss, same as the old boss. The king is dead, long live the king.


The writing has been on the wall for years, now: Why are we still here?

Comment Re:Legacy system based on Fox DB (Score 1) 617 617

MS-DOS never ran on an 8080, because MS-DOS didn't exist for the 8080, because the first IBM PC was based on a 4.77MHz 8088 and MS-DOS as we know it was not yet a thing until IBM approached Microsoft about an operating system for said IBM PC.

Meanwhile, an 8086 was a 16-bit CPU with a 16-bit bus, and the (somewhat later) 8088 was a 16-bit CPU with an 8-bit bus. They used the same (16-bit) instruction set.

tl;dr There has never been an 8-bit IBM PC, therefore there is no historical reason for 8-bit MS-DOS.

Comment Re:It was a BlackHat / DEFCON publicity stunt (Score 1) 26 26

Competent UNIX admin? Let me submit that it's just not needed to be competent with UNIX: You just need some basic knowledge of the concept of a subnet, and it might help to know what a broadcast domain is.

Anyone who can configure a venerable WRT54GL with OpenWRT or Tomato or DD-WRT and isn't afraid of a 900MHz ISM-band Ubiquiti (or other) radio can do this.

It's just Ethernet frames that happen to encapsulate IP. No big deal.

I mean, FFS: A couple of years ago I built such a system. A wealthy customer was having a party, and was having circuit issues on the bonded T1s at his house (yep, really) and Really, Really wanted his Sonos system to be reliably online to stream music for his guests.

We sent his wife to the Verizon store, and she came back with an LTE Wifi hotspot. I set up a WRT54GL running Shibby's Tomato-USB as a wireless client put the LTE hotspot in a window where it had reasonable signal. We had another WRT54GL working as a wired client off of this (triple-NAT? so what), which in turn plugged into the Sonos mesh with some Cat5.

DHCP figured out the addressing automagically; all I needed to do was make sure that each WRT54GL was issuing a unique subnet so Linux's routing tables weren't confusing itself.

And....done. It was an ugly hack thrown together late on a Saturday with parts on-hand and it got the party going just fine.

Which is the same as, or perhaps slightly more complicated than, a ProxyHam setup.

Oh, and ProxyHam is easily traceable, too: I haven't actually had my hands on Ubiquiti's 900MHz gear, but their 2.4GHz 802.11N stuff has an excellent and honest spectrum analyzer built-in with the default firmware. I would be shocked and amazed if their 900MHz parts differed in this regard.

A $100 radio, some graph paper, a directional antenna, a working brain and some mobility is all you need to use to triangulate the "isolated" end of a ProxyHam/ProxyGambit connection that is actively being used down to at least the household that the signal emanates from.

Alternatively, any spectrum analyzer that covers whatever band it is that is used to backhaul to the user's location can be used to locate them fairly easily: You can try, but at the end of the day you can never hide while broadcasting with a radio -- especially since we've largely abandoned frequency-hopping spread-spectrum (which was actually rather hard to narrow down using traditional tools).

Comment Re:Give it at least 13 more years (Score 1) 391 391

The functional difference between a microprocessor-controller washing machine and an electromechanically-controlled washing machine is insufficient to deem one robot, and the other not a robot.

In both cases, the use is the same: Dirty clothes go in. Time passes. Clean, damp clothes come out. Humans do the rest of the work, just as they have now for a very long time.

A modern front-load saves roughly zero human labor over a 60-year-old front-load.

Information is the inverse of entropy.