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Comment Re:D'oh (Score 1) 120

I thought GMS was introduced to address this issue (among other reasons) so that any bugs in new features could be fixed by sending out a GMS update, of course that doesn't solve the issue of not being able to push fixes for AOSP bugs directly to handsets.

That's the marketing pitch, but the reality is really much more sinister. The true goal is to replace AOSP with proprietary Google components.

http://arstechnica.com/gadgets...

Comment Re:Umm safety? (Score 1) 305

This seems easy to fix. Most (all?) states have some sort of annual safety inspection requirement for keeping a car on the road.

Nope, most states say it's too much of a pain, and don't do any of that. In most of the US, if the car runs and you don't get pulled over it's good to go.

https://en.wikipedia.org/wiki/...

Comment Re: Use Cisco instead... (Score 4, Informative) 76

Huawei firmware is not known for its quality. It has so many nasty bugs and security holes, the remote firmware programming interface is just a safer way to do it.

Cisco and Juniper are much better (at least their boxes crash or do idiotic things a lot less than Huawei boxes), but still not anywhere close to safe enough for the job, as one can easily check by hunting for C and J firmware exploits in several sites.

I always point to this video when people ask what my big deal with Huawei is. The takeaway, they found early 1990s bugs and security everywhere, including all memory being world accessible and mapped read, write, execute. That means you just need an exploit, no privilege escalation necessary. Also, not only are these exploits easy to find, Huawei doesn't publish CVEs or changelogs for their new firmware. Combine that with most debugging features only being available in Chinese.... Yeah, I'll pass.

http://www.youtube.com/watch?v...

Comment Re:Reflectivity map... (Score 1) 134

First Google result for Specular Map: "Specular maps are the maps you use to define a surface's shininess and highlight colour." Basically, every video game already does this. http://wiki.splashdamage.com/i...

One of the best videos I've seen showing some of the problems was the original Nvidia Ira tech demo. They mention things like how skin doesn't just reflect light off the surface, but absorbs and defracts it. http://www.youtube.com/watch?v...

Comment Re:Whats wrong with init? (Score 5, Interesting) 279

Lets face it, sysV init is complicated. Well, the theory behind the old linear start from init script 00 and move to init script 99 isn't, but the modern implementations and the scripts themselves are complicated. I mean you're doing dependency checking and a whole bunch of other things in bash scripts. Compare that to a systemd service file, which is overall nice and readable. So, part of it is factoring out the logic from the variables. The other big thing is bash and the tools used by init scripts are like using a sledgehammer to tap in a finishing nail.

I'm not going to say that systemd is perfect. I like the "unix" way which is to use small units that do one thing well instead of anything. That's part of the reason I see bash init scripts as too much for the job. Unfortunately, the systemd authors look like they want to throw in everything but the kitchen sink. Well, everything that they can't just port to kernel space that is. But that's the thing, Linux is a Monolithic kernel. Like it or not, the "Linux" way is to have one uber optimized thing with modules to handle everything.

In the end, I just really like the ease of use of service files. Oh, and the stupidly fast boot time on my laptop is really nice. People who say boot times don't matter aren't living in the real world.

Comment Re:photons are photons (Score 1) 40

Nope, nothing new to the Telcos or pretty much anyone who had to take a Signals course. The Nyquist rate has been known singe Harry Nyquist published it in 1928. The trick is that it sets a maximum number of symbols as twice the bandwidth. If you're only using one symbol (a '1' or '0') then the baud (symbol) rate is equal to the bit rate. If you're using more symbols like in modern systems (eg. 64QAM) then the baud rate doesn't change, but the bit rate (in Mbps) goes up exponentially.

Combining multiple transceivers which each use the same bandwidth but with different frequencies is also very common. It's a form of multiplexing, and is how many cell phones and cable modems can share the same wire without reducing throughput.

https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...

Comment Re:photons are photons (Score 1) 40

I'm only familiar with nyquist when it comes to audio phenomina... but if you're using more than half the bandwidth won't you have to deal with artifacting (aliasing in the audio world)?

Nope. The Nyquist-Shannon theorem deals with sampling rate. It says you have to be sampling at least twice as fast as the highest frequency if you want to perfectly decode the signal. The Nyquist rate deals with the maximum amount of data that can be transmitted. It says the absolute maximum symbol rate is equal to twice the bandwidth.

It's an easy mistake to make because the first is often called the "Nyquist sampling theorem," and they both deal closely with the same concepts. The wiki page I originally linked to was the Shannon–Hartley theorem, which is an adaptation to the Nyquist rate to account for noise reducing the theoretical maximum. It also explains Nyquist rate better than the actual Nyquist Rate wiki page. :/

https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...

Comment Re:photons are photons (Score 4, Informative) 40

Yes. The energy that gets you one single green photon gets you 75000 radio photons at the Cassini probe's X-band comm frequencies, for example. Having 75000 times more quanta means your system can be built on well-known classical principles (i.e. standard microwave radios) and work as expected.

But can one green photon hold more information than an RF photon?

The trick is when you're talking about bandwidth. "A key characteristic of bandwidth is that any band of a given width can carry the same amount of information, regardless of where that band is located in the frequency spectrum." Visible light is approximately "430–790 THz." While X-Band is "8.0 to 12.0 GHz" So you're talking about hundreds of THz vs 4 GHz.

Nyquist says the absolute maximum symbol rate is equal to twice the bandwidth. This means that once you've hit that cap, the only way to send more data is to either increase the number of bits per symbol or increase the frequency. Increasing the symbol rate can end up taking expensive delicate equipment, so it's easier to just throw a second transceiver at the problem. The second one would be exactly like the first, but would be operating at a slightly different frequency. The spectrum for light is a much larger playground for this than X-Band is.

https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...

Comment Re:Something doesn't make sense, at least for the (Score 1) 118

Am I the only person who considers it interesting that DigitalGlobe is prevented from selling high resolution images by the US while state governments are practically giving away even higher resolution images. This kind of crap is why conspiracy theories are so common. Though, my bets on good old government incompetence.

Comment Re:The last two red flags. (Score 1) 135

Umm, what's the point of any of that? That's like saying banks are a ponzi scheme because they constantly screw up paperwork, and don't like to let people withdraw large amounts of money.

Bitcoins are assets. This (DDOS) situation is somewhat like if the bridges to a warehouse/shopping center were deliberately destroyed. The assets are still there, you just can't get to them. Hell, they even have futures markets for the things. The problem is that it's very easy to create you're own exchange, but hard to follow the (deliberately complex) regulations that govern such an exchange.

Comment Re:Not blinded by laser but blinded nonetheless (Score 2) 376

The problem is that the legal limit is (in the UK at least) 60 watts. As there lasers will emit many more lumens per watt than the incandescent bulbs in use when the law was written, this doesn't stop them being much too bright.

So what you're saying is lawmakers didn't understand the technology they attempted to regulate, and ended up passing regulations that affect the wrong thing. (lumens vs watts) What a shock. Say it isn't so.

Comment Re:700 planes a year? (Score 1) 473

The problem is that overseas aircraft are treated the same as kit built ones by the FAA. They're "experimental" so you don't have to get FAA certified everything, but that's because non US parts normally aren't normally FAA certified, even if they're from the manufacturer. This sounds neat until you realize that these "experimental" aircraft are restricted by the FAA, and you'll be paying an insurance premium. Plus, you now have to worry about finding a mechanic that will work on your plane.

Comment Re:Use Class Rank (Score 1) 264

Fortunately, my university's grading policies were well known enough by employers in my field, so that the relatively lower GPA were taken into account when recruiting.

And we have the problem right there. I graduated from a uni like yours*, and like your example the businesses in the area take that kind of thing in question. The problem is for anyone who doesn't want to work in the same area. Unless the school is well known, the recruiter will take one look at your GPA and your application goes in the trash. Hell, some companies require you to apply online. I doubt the system ever even lets a human see the application if your GPA is below a certain number.

*Well, at least one that didn't pull punches when it comes to grading anyways.

Comment Re:Already Possible (Score 1) 195

It's relatively easy to get those features if you don't mind breaking all backwards compatibility. Which is what Android did.

It gives each separate process it's own UID, but has them all using a common display server. Then you combine the way that almost everything has to be done through the android framework with some special kernel patches. For instance, /etc is normally used for settings files, but that means special things have to be done if you want to mount root as read only. Especially since some of those files, like resolv.conf, must be updated while running.

Most good daemons already run as their own user/group. Android has just moved that from the application to the framework/installer.

On another note, I don't want things to be complicated to the end user. I just want to be able to easily have a read only root partition, and know that it and my kernel hasn't been tampered with evil maid style. I could go with encryption, but that no only eats some CPU, but it destroys DMA. Secure boot makes sure the kernel's ok, and simple file hashing makes sure they haven't been tampered with.

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