Archive for

December, 2013

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Fedora 20 released

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Fedora 20 was released a few days ago. J.A. Watson at ZDNet has a brief overview of the different desktops available, and concludes that for the most they run just fine on any hardware, including “sub-notebooks”. Furthermore, even though the “spin” of each desktop have specialised in their own applications, there are always plenty more to chose from in the main Fedora repositories.

The Anaconda installer was written back in release 18, and FedUp (FEDora UPgrader) is now the main system upgrade tool. It is not quite clear whether it is preferred to perform that on a running system though, as opposed to booting from an installer image.

Thus, the following links still apply, even for existing installations:

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Another assault on privacy by GCHQ

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Recently, it was revealed by IT Security Guru that the British intelligence agency GCHQ had demand a backdoor into the secure email service PrivateSky by CertiVox. At the end of 2012, GCHQ made the request, but CertiVox chose to close the service instead of betraying their customers. This is preceding the similar heavy-handed threats by NSA which caused US based Lavabit and Canadian based Silent Circle to shut down their secure email services.

It is clear then, that it is not possible to operate secure email or communication services within these countries. In that light, it’s interesting to see Swiss hosting companies picking up business. “Business for Switzerland’s 55 data centres is booming”, claims the article. It will be interesting to see how it plays out. Will they be pressured by US as was the case with the banks? Or will they also sell out, as was the case with the Swiss based Crypto AG and their machines?

As many have pointed out, the physical security of a data centre is often less of an issue than its network and system security. Furthermore, it’s a question of how it is used and what is offered. PrivateSky is for example still operational, but only for its owners. If somebody offered a secure communication service from within the Tor network, it would be both hard to detect, so it might fly under the radar for a while, and hard to take down if hosted in Switzerland. That’s a business idea right, up for grabs for anybody with a bit of spare time and money.

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VGA adapter for the Raspberry Pi

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Just tested a HDMI to VGA adapter for the RPi with my old CRT 1024×768 monitor. It works great! This was the HD2V04 HDMI to VGA + 3.5mm Audio Jack Converter Adapter Box from DealExtreme, at $21.70. The VGA port was a bit tight, so I had to make sure it was properly connected. Also, the monitor did not display anything before a cold restart of the Pi. It comes only with a USB power cable, to it means a wall wart or powered USB hub is required. (It should go without saying that you don’t want to power it off the Pi itself).

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DC-to-DC converters

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There are a number of different DC-to-DC converters out there, used to convert between different voltage levels. Ranging from the small but inefficient linear regulators to switched-mode converters like the buck converter that can achieve 95% or even higher efficiency. Among the switched-mode converters there are quite a few variations based on different but often similar circuit topologies: The buck converter is a step-down converter, and as the name suggest its output voltage will be reduced from its input. A boost (step-up) converter has similar design, but will do the opposite. A buck-boost converter combines the two so output voltage can be converted from both higher and lower input voltage. However, the traditional buck-boost converter inverts the polarity, so that the output voltage is of the opposite polarity than its input. A single-ended primary-inductor converter (SEPIC) (aka. buck-boost SEPIC) solves that problem, and delivers fixed non-inverted output throughout the range of its input voltage.

If this is all a bit confusing, have a look at Julian Ilett’s excellent YouTube videos and reviews: He covers the SEPIC buck boost converter, and shows how it seamlessly goes from 0.5 to 30 V out on a 9V battery. He shows how a 400W boost converter can drive a 100W LED pad, and he has a review of several different buck converters, in fact several reviews. He also has many interesting videos on driving different LED boards, including 50W and 30W RGB. You’ll really have to watch all his 140 videos!

When it comes to buying these, DealExtreme of course has a lot on offer, but here it seems like eBay has a bigger variety across its different sellers. I’ve already ordered this one, and expect to get more in the future. In particular, one of the variations on the ZXY6005 (D) power supply looks like a must-have in a hobby workshop.

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Trends: Snowden didn’t change public’s behaviour

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For all the NSA documents revealed by Snowden, and for all the news headlines stressing the gravity of the situation, it seems the general public has not changed their behaviour much. At least that would be the conclusion if looking at the worldwide trends of a few Google search terms: As can be seen in the first chart, the terms Snowden and NSA quickly rose to prominence when the story broke in the second half of 2013. However, interest quickly declined. If we look at the two next charts, comparing terms privacy, surveillance, encryption there seem to be no correlation with the former terms at all. Maybe there is an ever so faint increase in the term encryption, but nothing of significance.

The two last charts compare the terms encryption, surveillance in Germany. Here there is a small blip for the former term, while interest in the later, surveillance, seems to have increased significantly. This is possibly driven by the news stories there about NSA spying on Chancellor Angela Merkel.

These trends are rather disappointing to see. One would have hoped for at least a blip on the radar when it comes to public awareness of these issues. Instead, the distraction campaigns by most of the mainstream media seems to have been successful: The headlines have been focusing on Snowden, his girlfriend, his father, and whether he is a hero or traitor. Masking and excusing the abuse of power by NSA, GCHQ and the politicians who support these organizations have been successful. In fact, in Britain the story has taken the bizarre turn where the government is investigating The Guardian and editor Alan Rusbridger for publishing the leaked documents. What other clue do you need to see that the so called democracies and free countries of the West is nothing but a mirage for a powerful and abusive elite?

Swedish politician Rickard Falkvinge put it nicely in his post about the coming of the Swedish police-state:

A key difference between a functioning democracy and a police state is, that in a functioning democracy, the Police don’t get everything they point at.

 
 
 

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