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Comment: Re:Islamic idiocy... (Score 2) 474

by jandrese (#49558131) Attached to: Woman Behind Pakistan's First Hackathon, Sabeen Mahmud, Shot Dead
One could argue that the Islamic world went through an reverse of the Enlightenment. An unenlightenment if you will. People like to blame the British for screwing everything up (they certainly did not help), but really they were exploiting the repressive and regressive systems held in place by petty tribalism that long predated their appearance.

This is going to be a continuing problem until they figure out how to get some separation between church and state. This separation will be difficult to achieve so long as assassination of potential political rivals remains commonplace. The christian world had the advantage of making the separation back when a King could be reasonably protected against assassination by simply living in a castle and keeping a close eye on his advisers and family. Today with high power sniper rifles and small but powerful bombs available to any random stranger it is much harder to avoid being assassinated.

Comment: It wasn't better. (Score 4, Insightful) 331

by jandrese (#49557789) Attached to: Google Insiders Talk About Why Google+ Failed
The big problem with G+ is that it was basically Facebook by Google. They tried to make a big deal about the circles but I didn't know anybody who found that to be a compelling feature and it just made the site more of a headache to use. Plus if you really care you can do that on Facebook anyway. This wasn't like Myspace where the site was quickly swirling the drain and people needed someplace new to go. Facebook still works alright for most people (although the way they keep using every trick in the book to use "Top" view instead of "Most Recent" is still obnoxious) and their friends are already there. It never had that killer feature to overcome people's inherent inertia.

Comment: Re:and... (Score 1) 286

by jandrese (#49550313) Attached to: Tesla To Announce Battery-Based Energy Storage For Homes
Did you read the cost per battery? There is your answer right there. The summary talks about saving money by buying power during off peak hours and using the battery when power is expensive, but you'll never made $6,500 doing that before the battery wears out.

Also, the power company IS doing this, but only halfway. It's subsidizing half the cost of the system up front. Honestly, this whole thing makes a lot more sense for the power company than it does for the end consumer.

Comment: Re:I call bullshit on anything from Forbes (Score 1) 134

by jandrese (#49531445) Attached to: New Javascript Attack Lets Websites Spy On the CPU's Cache
It's a cache timing app. Pretty impressive that they were able to maintain the precise timing necessary to conduct the attack in Javascript, but still quite limited in what it can collect. Basically they can tell if certain cache lines are in use, and figure out maybe what those lines are shared with to do some behavior analysis on the victim. This application is a bit of a stretch, since learning the allocation patterns is not going to be easy.

Their other example is a user that has a machine with two VMs on it. One is highly secure (no network access) but has been rooted. The other has network access but no normal connection to the rooted VM. You can pass data from the secure VM to the network VM and then ex-filtrate the data using a malicious advertisement injected into a normal browsing session. It does require the victim to not understand that VMs are not airgapped though.

Comment: Re:Not very useful. (Score 3, Interesting) 134

by jandrese (#49531403) Attached to: New Javascript Attack Lets Websites Spy On the CPU's Cache
The paper assumes that your problem is exfiltrating data because the target has somehow gotten infected but is ultra-paranoid about outbound traffic from his machine. You can instead transfer the data to a javascript app running in a webpage on a different VM that may be less secure. It seems pretty cornercase to me, but every time I think that someone comes out with some crazy exploit that extracts all of your SSH keys or something from the box using what seems like a nearly useless exploit.

Comment: Re:80% through tunnels? (Score 2) 189

by jandrese (#49523315) Attached to: Maglev Train Exceeds 600km/h For World Record
My guess is that going pure pneumatic is probably inefficient and more difficult to build. A hybrid system probably make more sense, if for no other reason than you don't have to maintain an airtight seal around the car for an entire 1000km journey. Electric motors are pretty reliable and relatively inexpensive.

Comment: Re:80% through tunnels? (Score 3, Interesting) 189

by jandrese (#49522453) Attached to: Maglev Train Exceeds 600km/h For World Record
Then every car (and the tunnel itself!) needs to be a pressure vessel and you need oxygen masks if there is a leak. Plus you have to turn every station into an airlock. Depressurizing the tunnel is a lot of extra work.

It might be easier (although not much more sane) to have two large ventilation systems for the tunnel. One working at high negative pressure (near vacuum), and the other working at a high positive pressure. The vents would be shutters that could be opened and closed rapidly, so you're always pulling air from the front of the train and introducing it behind the train. Basically you would always have a strong tail wind, reducing the heating effects of compressing that much air. The energy required to move the air would be substantial though, and it might not make sense. The high speed shutter system would be relatively complex too, and making it reliable would be a challenge.

Comment: Expensive and fragile (Score 3, Informative) 96

by jandrese (#49521065) Attached to: Optical Tech Can Boost Wi-Fi Systems' Capacity With LEDs
Optical networking startups are littered through history. Ultimately the tech works, but has caveats like you can't move your machine around without losing connectivity, and you also lose connectivity whenever someone walks in front of the beam. Also, they tend to be expensive, and since the machine ends up having to be basically immobile anyway it usually makes sense to just run cables instead.

Even for Point to Point links where you can't easily run cables (to a building across the street for example), you end up with a reasonably fast link that still cuts out when there is heavy rain or a bird lands in front of it or something. 100Mbps is really nothing to write home about either. In 2015 you should be pushing more like 1Gbps over an optical link to make it even somewhat attractive compared to plain old WiFi.

Don't panic.