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Grinch Vulnerability Could Put a Hole In Your Linux Stocking

buchner.johannes As bad as ShellShock (59 comments)

So is ShellShock fixed now?
I gathered the basic variant is, but then people developed other variants.

2 hours ago
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BitTorrent Launches Project Maelstrom, the First Torrent-Based Browser

buchner.johannes Re:Private? (67 comments)

The point was more than any request for data my bittorrent client receives from a peer, I can also request from the network. So nothing is secret.

about a week ago
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LA Mayor Proposes Earthquake Retrofits On Thousands of Buildings

buchner.johannes Re:the mysterious "us" (178 comments)

The reason that the discussion isn't framed more to be about the safety of citizens is because it's assumed that people understand to have buildings not collapse in an earthquake is a generally good thing for everyone. Do you really have to have a discussion about how not having buildings collapse onto people inside them is a good thing or a bad thing? We even have some pretty good numbers of the costs associated with earthquakes, as they happen frequently enough in plenty of developed and undeveloped areas.

Isn't this a usual risk-cost calculation? Every building can decide whether the risk (probability times loss) is greater then the costs of avoiding the risk.

about a week ago
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LA Mayor Proposes Earthquake Retrofits On Thousands of Buildings

buchner.johannes Re:the mysterious "us" (178 comments)

Normally yes, but the problem is that they're unaware that this was motivated by *two* significant earthquakes this year, signaling the end of a decade-long low cycle.

There are Earthquake *cycles*?
[citation needed]

about a week ago
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BitTorrent Launches Project Maelstrom, the First Torrent-Based Browser

buchner.johannes Private? (67 comments)

For normal websites, I can see the benefit of requesting data blocks identified by hashes. But doesn't bittorrent require that all data you download is shared between peers? How can any secure, private connections be handled, like banking or shopping?

about a week ago
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French Publishers Prepare Lawsuit Against Adblock Plus

buchner.johannes Re:Doesn't matter even if the publishers win... (687 comments)

I think the original post is delusional. People would still use AdBlock if ads were unobtrusive and static. They just want the content, just like they download movies without paying.

I am willing to bet that the fraction of AdBlock users that turn on the feature where some ads are allowed does not exceed 1%.

Humans want all of it, for free, and now. If they can't have it under those terms, blaming "stealing" on the providers is only half of the story.

about two weeks ago
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Pluto-Bound Spacecraft Ends Hibernation To Start Mission

buchner.johannes Re:As far as I'm concerned, Pluto is still a plane (77 comments)

Sure, it might have originated in the Kuiper belt, but it isn't there any more.

That's not the point. The point is it has three moons of the same size as itself, and a lot of other debris. It's not dominating its environment.
You can choose: Either we have 8 planets, or you have to learn 19 names, and new ones every year or two. 9 is not an option anymore.

Anyways, I don't understand why "dwarf planet" was not made a subclass of "planets" along with "major planets" (where the others go). But no, it is "planets" and "minor planets", which are by definition not a "planet".

about two weeks ago
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Aliens Are Probably Everywhere, Just Not Anywhere Nearby

buchner.johannes Re:Drake is Obtuse (334 comments)

I've always felt that the Drake Equation is not worthy of the term 'equation' since its just a simple probabilistic estimate from multiplying a ton of other probabilities and instances together.

It has a term on the left and a term on the right, and an equal sign in between. You can also see the Drake Equation as a Bayesian Network combined with a Poisson estimator for the mean (n*p).

about two weeks ago
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New Effort To Grant Legal Rights To Chimpanzees Fails

buchner.johannes Re:good (341 comments)

Chimps aren't people. The laws for humans don't apply.

Why are Chimps not people? What exactly separates humans from non-humans?

about two weeks ago
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New Effort To Grant Legal Rights To Chimpanzees Fails

buchner.johannes Re:good (341 comments)

Regardless of the decision, I think it is good that people are forced to argue why.

about two weeks ago
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The Cost of the "S" In HTTPS

buchner.johannes Yes (238 comments)

Caching: You can not cache Facebook for example, because the content is generated differently for every user. Youtube goes through great lengths to prohibit caching (e.g. with Squid) in the first place.
Proxying: You can proxy https just fine.
Firewalling: You can firewall https just fine.
Parental control: You can block websites just fine, either via DNS or IP.
I suspect they mean snooping for "copying that companies don't approve of" and "freedom fighters" here. And child pornography. It's kind of the point of HTTPS that it should be private. So yes, I can accept these costs.

about two weeks ago
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Why Pluto Still Matters

buchner.johannes I am Pluto? (91 comments)

But I think there’s something even more compelling at play here: most of us learn about Pluto as children, and as a child, Pluto reminded me of myself. It’s smaller than all the other planets, and it was the newest one to come along. To me, it represented all the undiscovered mysteries, all that was still unknown, and the hope that someday, it might matter more. I was actually rooting, as a kid, for Pluto to be bigger than Mercury, simply because I wanted it to be more important in some measurable way. And because it took longer to orbit the Sun than everything else, because it was different from all the other planets in practically every way, I truly believed it was special.

It’s been some thirty-odd years since I was that child, learning about Pluto for the first time, and in those same thirty-odd years, our estimation of the Solar System has grown to make it a larger, more well-known place. But in that same time, I’ve grown, too, and the most important lesson I’ve learned about Pluto—that I would have told my young self if I could—is this:

The fact that there are other things out there that are bigger, smarter, faster, stronger, or better than you, in any regard, in absolutely no way diminishes how special you are.

Compare that to Neil deGrasse Tyson:

Pluto is not a planet. GET OVER IT!

Maybe there is something to it and astronomy should incorporate peoples feelings in their classifications. Probably not.
But maybe in the communication? Actually i think they could have classified planets in "Big planets" and "Dwarf planets" instead of making "dwarf planets" not a subclass of "planets".

about two weeks ago
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Stars Traveling Close To Light Speed Could Spread Life Through the Universe

buchner.johannes Re:I don't understand this ... (184 comments)

Not all supermassive black holes are actively accreting. In fact, the fraction of time their accretion disks actually output massive amounts of radiation is ~10%, on patches of ~ hundred million years timescales.

A planetary system could form outside the center of the galaxy and travel close to the galactic center. You have to keep in mind that the distances between stars are enormous when compared to distances between planets. For example, our nearest star is 270 000 earth-sun distances (4 lightyears) away, while Jupiter is only 5 earth-sun distances from the Sun. So a "stripping" of planets, due to tidal forces, is extremely small, even when it comes close to the supermassive black hole in the center of the galaxy. It is true however that for the closest orbits, such as 120 earth-sun distances for S2 (S2 reaches speeds of 5000 km/s), this effect will be important. However, I suspect that while a single, quick swing-by will alter the orbits of planets (generally increasing ellipticity), that effect leads to the immediate destruction of the entire system. Normal planetary systems are also not stable systems. Changes in the orbits, interactions between planets, etc. are common; Only when stable oscillations are reached, the orbits remain the same for a few million years. So I suspect that the planets can re-arrange into a stable system (perhaps under ejection of one of the planets).

I think the changes are better if the system is a newly born star, where planetoids are still forming in a thick disk of gas and dust. Then, the partially destroyed disk can re-arrange quickly and form planets after swing-by. That would not necessarily be a problem for "spreading of life", if this process occurs e.g. via comets.

about two weeks ago
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Stars Traveling Close To Light Speed Could Spread Life Through the Universe

buchner.johannes Re: Cubic gigaparsec ... (184 comments)

Unfortunately, space is not Euclidean on giga-parsec scales. Here, when talking about 5000 Gpc, they refer to a "comoving scale". That is a scale where the expansion of the universe has been divided out, so that e.g. the same number of galaxies remain in this box. So if you would place the atoms of the number of swimming pools you computed in the volume, they would be twice as dense at the largest distances, where the Universe was half the current size. Also, the largest distance within a 5000 Gpc^3 is 3200 Gpc (space is not Euclidean).

about two weeks ago
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New Analysis Pushes Back Possible Origin For Antikythera Mechanism

buchner.johannes Re:Tower of the winds (62 comments)

What happens when you link the Antikythera mechanism with the Kythera mechanism? Fusion experts should investigate!

about three weeks ago
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Debian Forked Over Systemd

buchner.johannes Re:http://uselessd.darknedgy.net/ (647 comments)

Yes, so what init system and service management are they going to use?
Is it meant just for servers? Then they could get away with sysvinit.

If this Debian derivative is meant for desktops too, then you want some type of the systemd solutions to service management, to dynamically change hostname, datetime, do hibernation, add/remove bluetooth/modem devices, multi-seat login, etc...

I think the options are: Upstart or OpenRC; the others are too obscure or untested.
Probably you would have to use the abandoned Consolekit to replace logind?

If you are unfamiliar, this is what (systemd-)logind does (and previously ConsoleKit did part of it):

.
        keeping track of users and sessions, their processes and their idle states,
        creating control groups for user processes,
        providing PolicyKit-based access for users to operations such as system shutdown or sleep,
        implementing a shutdown/sleep inhibition logic for applications,
        handling of power/sleep hardware keys,
        multi-seat management, session switch management, and device access management for users,
        automatic spawning of text logins (gettys) on virtual terminal (console) activation and user runtime directory management.

from https://access.redhat.com/docu...

about three weeks ago
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Complex Life May Be Possible In Only 10% of All Galaxies

buchner.johannes Re:I am dubious (307 comments)

The point is really that we don't nearly know enough to answer any of these questions. We can provide "best current thinking," but with only 1 actual sample (Earth) and no experience with GRBs, these are just guessitmates at best.

That's not true. We know the luminosity output of GRBs very well, as well as their spectrum across the electromagnetic spectrum. For a number of exoplanets (and the planets in the solar system) we know their main atmospheric content. For each composition of atmospheres you can predict the effects of a GRB for any chosen distance in terms of photo-dissociation, heating and radiation pressure. I don't see great unknowns there.

- How many planets might have other special circumstances that protect their ozone (such as a lack of N2 in their atmosphere, or an ozone generating biology in their stratosphere, etc.)

Not sure. I think it is possible to come up with such scenarios as you stated, but it has to be shown that they are frequent occurrences to be relevant for changing the survival rate of complex life.

Exactly. To say that GRB==doom means that all of these possibilities must be very infrequent indeed, and I just don't see how we can say that at present. That makes me dubious about the hypothesis.

I think it can be argued that due to the luminosity output of GRBs, that "GRB==doom" holds, within a certain radius and for typical orientations. That serves as a useful starting point. For special orientations, or special atmospheres that one could imagine, this may not hold. But then the burden is on the person dreaming up these scenarios to show that these can more happen frequently than expected due to random orientations and atmospheres representative of the gas make-up of observed stellar and star-forming systems (which is well-studied as well, the technical term is metallicity and (heavy) element abundance). Until then, I think "GRB==doom" is a suitable working hypothesis we can adopt.

about three weeks ago
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Complex Life May Be Possible In Only 10% of All Galaxies

buchner.johannes Re:Practically alone... (307 comments)

Actually, it's only 17 million. A quick calculation gives me that the number of galaxies within 5 billion light-years is 170 million. Neglecting very small, dwarf galaxies, which are more numerous but have drastically fewer stars, I multiplied the stellar mass density by the comoving volume up to z=0.5.

about three weeks ago
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Complex Life May Be Possible In Only 10% of All Galaxies

buchner.johannes Re:I am dubious (307 comments)

I can not answer about the deadliness of GRBs, but I think you will find those answers in Phil Plaits book "Death from the Skies!".

- How many civilizations might form on bodies with very thick atmospheres, far from their Suns? (Venus does not need a ozone layer to keep the UV out, and might be very habitable a few AU out.)

Yes, insulation is a good idea. But the planet will always radiate as a black body and loose energy, which has to be re-supplied by the suns radiation. The radiation drops with the square of the distance, so rather quickly. These considerations (make-up and size of planets) go into calculations for the habitable zone.

I can also imagine that a GRB comes with considerable photon pressure and might strip the entire atmosphere off a planet, or heat it to a point where it dissipates into space.

- How many planets might have very long rotation periods (years), so that the night hemisphere never is subjected to the daytime UV?

I think the rotation of planets around their own axis (spin) is not known outside the solar system. Generally, the spin is generated from formation of planets in the rotating protostellar disk, but interactions and changing orbits may modify the spin (Venus, Uranus).

- Are there rotation axis directions and orbital precession constants for planets that would keep GRB radiation mostly in one hemisphere, leaving the other to develop?

If you do not have the problem of heating and evaporation of the atmosphere I mentioned above, then yes, that is probably possible. For example if the GRB goes off from the direction of the spin axis ("below/above the solar system"). This may safe you from one GRB, but since GRBs come randomly from all directions it is not failsafe across many billion years.

- How many planets might have other special circumstances that protect their ozone (such as a lack of N2 in their atmosphere, or an ozone generating biology in their stratosphere, etc.)

Not sure. I think it is possible to come up with such scenarios as you stated, but it has to be shown that they are frequent occurrences to be relevant for changing the survival rate of complex life.

about three weeks ago

Submissions

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Btrfs becomes stable, releases v3.12

buchner.johannes buchner.johannes writes  |  about a year ago

buchner.johannes (1139593) writes "Btrfs is the next-gen filesystem for Linux, likely to replace ext3 and ext4 in coming years and filling the space between ZFS and Reiser4. Btrfs offers many compelling new features but development has been a long time coming in the "unstable" status leaving many users unsure whether to entrust their data to. Since August, their web page declares Btrfs as stable. Have you tried it since? What has been your experience with Btrfs? Fedora users probably are already using it on a daily basis."
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My primary work is

buchner.johannes buchner.johannes writes  |  more than 2 years ago

buchner.johannes (1139593) writes "My primary work is
  [a] developing software for a company
  [b] developing software for a research institute
  [c] research
  [d] management or consulting (not coding)
  [e] I'm unemployed
  [f] something else"
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WebM license made GPL and Apache compatible

buchner.johannes buchner.johannes writes  |  more than 4 years ago

buchner.johannes (1139593) writes "Google updated its licensing terms for WebM, which is now a pure BSD license, with a standalone patent grant.

Using patent language borrowed from both the Apache and GPLv3 patent clauses, in this new iteration of the patent clause we've decoupled patents from copyright, thus preserving the pure BSD nature of the copyright license. This means we are no longer creating a new open source copyright license, and the patent grant can exist on its own.

Here is the WebM license FAQ. Time to make a GPLv3 fork?"
Link to Original Source

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Ethics of producing Non-malicious Malware

buchner.johannes buchner.johannes writes  |  about 5 years ago

buchner.johannes (1139593) writes "I was fed up with the general consent that Linux is oh-so-secure and has no malware. After a week of work, I finished a package of malware for Unix/Linux. Its whole purpose is to help whitehat hackers point out that the system can be turned into a botnet client, by simply downloading BOINC and attaching it to my user account, helping scientific projects. It does not exploit any security holes, but loose security configurations and mindless execution of unverified downloads: I tested it to be injected by a PHP script (even circumventing safemode), so that the web server runs it, hell I even got a proxy server that injects it into shell scripts and Makefiles in tarballs on the fly, and adds onto windows executable for execution in wine (Z: is /). If executed by the user, it can persist itself in cron, bashrc and other files. The aim of the exercise was to provide a payload so security people can 'pwn' systems to show security holes, without doing harm (such as deleting files or disrupting normal operation).
But now I have a problem: I am unsure of whether it is ethically ok to release this toolkit, which, by ripping out the BOINC payload and putting in something really evil, can be turned into proper Linux malware. On the one hand, the way it persists itself in autostart is really nasty, and that is not really a security hole that can be fixed. On the other hand, such a script can be written by anyone else too, and it would be useful to show people why you need SELinux on a server, and why verifying the source of downloads (checksums through trusted channels) is necessary.
Technically, it is a nice piece, but should I release it? I don't want to turn the Linux desktop into Windows, hence I'm slightly leaning towards not releasing it. What does your ethics say about releasing such grayware?"
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Common charger for mobile phones coming in the EU

buchner.johannes buchner.johannes writes  |  more than 5 years ago

buchner.johannes writes "The EU Commission and companies agreed on common charger for mobile phones:

Incompatibility of chargers for mobile phones is a major inconvenience for users and also leads to unnecessary waste. Therefore, the Commission has requested industry to come forward with a voluntary commitment to solve this problem so as to avoid legislation. As a result major producers of mobile phones have agreed to harmonise chargers in the EU.

Discussed before here and here. The text continues:

Industry commits to provide chargers compatibility on the basis of the Micro-USB connector. Once the commitment becomes effective, it will be possible to charge data-enabled mobile phones from any charger compatible with the common specifications.

"

Link to Original Source
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Your average disturbance timescale?

buchner.johannes buchner.johannes writes  |  more than 5 years ago

buchner.johannes (1139593) writes "In your office, your work is disturbed or interrupted on average after (e.g. people walking in, calls, etc.)

  — less than 5 minutes
  — less than 15 minutes
  — less than 30 minutes
  — less than 2 hours
  — more than 2 hours
  — depends on how fast slashdot throws out stories"

Link to Original Source
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Jake looking for developers

buchner.johannes buchner.johannes writes  |  more than 5 years ago

buchner.johannes writes "Jake is the new kid on the block for team collaboration. Developed by students in Vienna, this serverless, open-source, cross-platform versioning tool is aimed for non-developers. What makes Jake unique is that the communication is done over XMPP, and that the look-and-feel is very native (unlike most Java apps).
We turn to Slashdot as we look for developers interested in picking up the work, forking it, contributing or reusing concepts in other projects. Slashdot already discussed the need for a painless, easy-to-use tool once. About Jake shows a small comparison to other tools."

Link to Original Source
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Bittorrent reverse hash database

buchner.johannes buchner.johannes writes  |  more than 7 years ago

buchner.johannes writes "Story at: http://twoday.tuwien.ac.at/jo/stories/305252/
This is probably the first reverse hash database for torrent files.

When watching torrent traffic as an network administrator, you might want to know if the data is legal and complies to your policies.
On the other hand, if you see a torrent loading in your network as a user, if you know what it is, it might be _very_ interesting to join it, as the speed can be expected to be very high.
Database at: http://stud4.tuwien.ac.at/~e0625457/bittorrent/hostedsummary.html"

Link to Original Source

Journals

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Jake looking for developers

buchner.johannes buchner.johannes writes  |  more than 5 years ago Jake is the new kid on the block for team collaboration. Developed by students in Vienna, this serverless, open-source, cross-platform versioning tool is aimed for non-developers. What makes Jake unique is that the communication is done over XMPP, and that the look-and-feel is very native (unlike most Java apps).
We turn to Slashdot as we look for developers interested in picking up the work, forking it, contributing or reusing concepts in other projects. Slashdot already discussed the need for a painless, easy-to-use tool once. About Jake shows a small comparison to other tools.

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