September of 2016 was a busy month for a few reasons, one of these being the two weeks I was (with the rest of our IQC team) in Smiths Falls outside Ottawa conducting trials of our prototype quantum key distribution system. Ultimately this involved transmitting quantum signals from our ground-station quantum source to our receiver on a flying NRC aircraft—quite successfully, I might add. In the intervening time to now (and modulo one vacation to Australia and New Zealand) we wrote-up our results into a paper, the pre-print of which recently appeared on the arXiv.

At the same time (not coincidentally) an article about our work appeared in the Canadian newspaper The Globe and Mail—page 1 on Dec. 21, in our region—as well as the Waterloo Region Record (pg. 2, Dec. 22). You can read the online edition of the article.

So that's neat.

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I use Debian with KDE's Plasma desktop environment. I usually track Debian's testing repository, but often I like to upgrade the version of KDE packages installed to more recent versions in the unstable repository. My preferred way:

sudo aptitude --visual-preview -t unstable install ~i~mkde

The action tends to be independent of anything else, but that's easy enough to work around—update per usual before running.

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For some time, I've been happily using Unison in conjunction with my Android phone's USB mass storage function to synchronize files between my phone and my desktop. It was simple: I'd plug in my phone with USB and enable the SD card to be used as a mass storage device, then mount it in Linux and run Unison as if the phone was a local folder (with appropriate tweaks to support the FAT filesystem).

Alas, my phone was getting on in years (or months, as it is in tech), and with support long dropped and capacity nigh exhausted, I had to upgrade. With my new phone I've been promoted to the “new hotness” that is Android 6 Marshmallow, but one of the functions that was dropped along the way was the ability to expose the SD card as mass storage over USB. Admittedly it wasn't a perfect solution, requiring unmounting …

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We take our quantum key distribution system out of the laboratory and mount it in the back of a small truck. Integrating a two-axis pointing system at both sites, polarization correction, and time-of-flight compensation, we demonstrate quantum key distribution from a stationary transmitter to a receiver moving at an angular speed (relative to the transmitter) equivalent to the maximum angular speed of a typical low-Earth-orbit satellite.

Bonus: Read the IQC's news release, which covers both this and the previous paper for a general audience.

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Fundamental laws of quantum physics guarantee the security of encryption keys generated through quantum key distribution, in contrast to standard encryption techniques which rely on assumptions about an eavesdropper's computational ability. That said, special technology is necessary to facilitate quantum key distribution transmissions between parties that are more than a couple of hundred kilometers apart.

A near-term solution is to use an orbiting satellite as a trusted quantum receiver. Here we detail specifically chosen algorithms that make up an implementation of quantum key distribution, suitable for a satellite receiver platform. We examine these algorithms' computational requirements while demonstrating them experimentally as we emulate the variable channel losses that would be experienced during a satellite pass (following those we published about previously).

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As a consequence of their recent effort to boost the numbers of Windows 10 installs using any means possible, however questionable, and turn their paying customers into beta testers, Microsoft have been especially hostile to their users as of late, installing nag-screens and “telemetry” code (also known as “spyware”) under the guise of important updates to existing installs of previous versions of Windows. While I would happily eschew Windows for Linux on all the machines I use, and have largely done so, the idea of avoiding Windows in totality is, sadly, not yet practical―the common-use machines I maintain in our lab required it for various reasons, and even I still keep a Wintendo partition.

There are plenty of discussions around about what to do about this. Here's a fine example. Though this is intended for my own reference, I've had success with the following:

wusa /uninstall /kb:2952664 /norestart …

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