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Comments

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Linux Foundation, Linux.com Sites Down To Fix Security Breach

WindShadow Re:More Info, and Announcement Content (101 comments)

The information I really want to see is a statement clarifying this as either technical as in a failure of the security software somewhere, or administrative, as in someone left something open through error or poor security design choices.

It's important to know if this is a bug which is on all Linux systems, or someone made a human error.

more than 3 years ago
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Linux Foundation, Linux.com Sites Down To Fix Security Breach

WindShadow Re:SSH keys? (101 comments)

That being said, it's important to use a different private key on each machine where you might ssh from...

Hell yes, and for key management sanity it is good to use a clear comment on keys so you know what they are for.

However, in case of a compromise, you'd still need to remove trust in the private key of the impacted machine (so if kernel.org got hacked, you need to remove your old kernel.org's public key from your ~/.ssh/authorized_keys on linux.org)

You also have to rebuild authorized_keys to check that no new or modified keys have been added. That would allow the hackers right back in at some future time. I keep a copy and cksum of authorized keys for every machine where I use keys, just so I can check. Yes, I'm paranoid.

Also, if the hacker got kernel.org's /etc/ssh/ssh_host_rsa_key, then he could theoretically later on mount an MITM attack against kernel.org... so the kernel.org admins better change that one as well (while publishing the new key's fingerprint on an SSL server).

I don't know if that's the case, but they could certainly set up a fake server if they have your public key and the server host keys. So generating a new host key pair is really required, forcing every user to change the key.

What a mess!

more than 3 years ago
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Why We Don't Need Gigabit Networks (Yet)

WindShadow High thruput needs network tuning (359 comments)

Actually some pretty modest hardware will generate very high thruput if tuned properly. The network stack default parameters we use today are remnants of what we did in the the 90s, when 16MB RAM was big, 4Mbit token ring was used, and 100k for a network buffer was a lot.

To increase thruput there are several things which can be done. The first is to increase the window size so that data can flow until the ACK packets get back. The second is to increase the packet size (aka jumbo packets, or MTU). After that you need to allocate enough buffer space to keep the pipe full on the transmit end and prevent buffer overflow on the receiving end. The OS needs to prioritize interrupt handling so the incoming data get handled, it doesn't need a lot of CPU, but it needs it NOW.

Finally, realize that the disk subsystem may become a bottleneck at Gbit speeds, sustained transfer to/from disk may take more than the minimal bargain drive. You don't need super hardware to use that Gbit, but you do need some optimal use of the hardware you have.

more than 3 years ago
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Kepler Discovers 'Phantom' Exoplanet

WindShadow Re:Not 'unprecedented' (78 comments)

They aren't exoplanets, and hence not a precedent.

You sound a bit like a patent attorney explaining why something isn't prior art. We have found exoplanets by star wobble and solar planets by planet wobble, I think "unprecedented" is an overstatement, just my opinion. The method was certainly used previously in this system.

more than 3 years ago
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Boost Your Wi-Fi Signal Using Only a Beer Can

WindShadow Re:Bars (229 comments)

Since when is WiFi signal strength measured in bars? It's a pressure unit.

This method uses a beer can, of course it's measured in bars, where would you measure it, in churches?

more than 3 years ago
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The Coming Energy Turnaround In Germany

WindShadow Re:Be patient (394 comments)

So wait; we have a choice between a set of power sources which provide indefinite quantities of energy; where the installation, once done, is pretty much forever and just needs small scale maintenance; where the major influence on the environment is extremely localised and quite easy to understand and reduce and another power source which provides energy now but where later we have to look after nuclear waste for hundreds of thousands of years. Where the major cost is decommissioning and clean up which happens at the end and where almost all cost estimates basically assume the tax payer covers that for free.

That sounds great, what energy source is that? Because people living on the east coast of the US would sure like to get all those nasty polluting coal plants in the west shut down. The ones that put so much sulpher in the air that the acid rain makes the limestone bubble? Similar to the ones in Japan where you can develop photographs in some of the lakes?

Please let us know what power source you are talking about, because "Clean Coal" is an advertising slogan, not a reality. The technology to capture the SO2 and CO2 would raise the cost higher than buying politicians.

more than 3 years ago
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Researchers' Typosquatting Stole 20 GB of E-Mail

WindShadow Re:Good test. (204 comments)

Not true, at least in the UK:

Interfering with mail - Postal Services Act 2000 Section 84 Triable Summarily (Magistrates court) 6 Months and or a fine (Max) A person commits an offence if they without reasonable excuse intentionally delay or open a postal packet in the course of transmission by post or intentionally opens a mail bag. A person commits an offence if, intending to act to a person's detriment and without reasonable excuse, opens a postal packet which they know or suspect to have been delivered incorrectly.

And there's the rub, if the mail is delivered as addressed, can it be said to be delivered incorrectly? This is why lawyers exist, to convince a judge or jury that what the law says is not what it means.

If you work for the Post service you could commit other offences under Section 83 triable either way (Magistrates or Crown court) and get a sentence of 2 years and or a fine.

more than 3 years ago
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LSD Alleviates 'Suicide Headaches'

WindShadow It seems that Viagra does too (272 comments)

I have seen several articles lately (Example) suggesting the Viagra is useful in some people for fighting migraine and similar headaches. I don't know if old age or biofeedback was my solution, but I'm sure before I found relief I would have tried almost anything.

more than 3 years ago
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Dual-core Smartphone Runs Android and Ubuntu

WindShadow Why this is useful (148 comments)

Previous articles about phones being bricked by Exchange mail admins led VMware to develop a phone hypervisor to run a 2nd copy of the phone OS, so you could have a business phone VM (with a separate number) and if something was done to the business phone, the personal phone would still be functional. Note that clearing all mail and contacts information seems to be a "feature" of Exchange, ie. a requirement rather than optional. While this is acceptable for a company provided phone, it's not for a personal phone being used for business for the benefit of the company.

Running a full function OS on a phone may or may not be as useful, in general the UI is not optimized for a small touch screen, so usability might be less than desired. This would make more sense on a tablet, using a netbook spin of Fedora or Ubuntu as a base, or Meego, or one of the small distributions like Puppy (build it for ARM?).

Other than providing some extra CPU power, I don't see that being dual core is in any way a requirement, unless the HVM is missing in the single core models.

more than 3 years ago
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Obama Wants Big Hike In Cybersecurity Research

WindShadow Re:Easy. (73 comments)

When I was doing work requiring clearance (DoD and DoE at various times) there was a lot of stuff to understand about need to know. Having low level clerks see things I would restrict to cabinet level access is stupid, and no new research needed, just applying principles practiced in the 1970s.

Given the chance to design an access system, I would have a "can see" bit map and put characterizing bits (flags, whatever) on each item, so unless someone was cleared for all characteristics of a document or folder, they wouldn't even see that it exists.

I'm skipping some implementation details which are important, this isn't a technical forum, and I know they exist.

more than 3 years ago
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With Better Sharing of Intel Comes Danger

WindShadow This is a truely flawed view of the problem (287 comments)

The problem is not the media, but the access to data. Given the breadth of the information topics, no one below cabinet level should have been able to see it all, much less some low level clerk. This was a failure of the need to know policy, and the attempt to blame wikileaks or the clerk for the release is clearly an attempt to disguise the failure of method. I covered the technology and ethical issues at length in a blog post when it happened.

I have held DoD and DoE clearance, and have worked with information control for companies like GE and SBC (now at&t)

more than 3 years ago
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5 Years of Linux Kernel Releases Benchmarked

WindShadow CPU-bound no better, disk & network worse (52 comments)

This comes as no surprise. In any activity which is mostly limited by CPU in user mode, not much changes, you can track that over a number of operating systems. What has gotten slower is disk io and network transfer time, and some tests, such as web serving, may be using all or mostly pages in memory, so this is not as obvious as it might be.

In addition, the test was run in a virtual machine, so to some extent the huge host memory provided more resources, and the very fast disk hides poor choices in the io scheduling and provides additional write cache and buffers. In other words, neither the tests chosen, or the environment used, were typical for small server or generous desktop.

For a meaningful test no more than four CPUs (or two with hyperthreading) should be used, and all io should go to a real rotating disk, like a $100 1TB WD or Seagate, and the filesystems should be on that, not some fancy large SSD. Then some numbers can be identified which reflect the performance on machines in the small server or fast desktop price range of a motivated home user or budget limited small business. Then the limitations of the CPU and io scheduler changes will be more evident, and perhaps the performance using the deadline scheduler should be included, since discussions on Linux-RAID mailing list indicate that many of us find the default scheduler is a bottleneck for typical loads (particularly raid-[56]).

more than 3 years ago
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Voting Machines Selecting Default Candidates

WindShadow Re:*Citation Needed* (794 comments)

I'd just like to point out that one of the core founding ideas of your nation was "no taxation without representation".

And they let college students vote at school if they bother to register. Since the colleges are all tax exempt we now have representation without taxation.

more than 3 years ago
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Generic PCs For Corporate Use?

WindShadow Don't compare apples and oranges (606 comments)

It sounds like you could compete with Dell and that you should start a company. Maybe then you realise that 1kUS$ isn't that much for a system.

The saving is in that he isn't starting a company. So he has no costs for inventory, advertising, shipping, distributor discounts, etc. If he is building a dozen systems he can't win on cost over the hardware lifetime, but if he is building hundreds, he says he needs that many, he probably can shave quite a bit of the cost. But how much hardware is going on those machines, to drive the cost that high? Dell sells a reasonable office machine for just under $600, without massive discounts. Companies like eMachines go lower than that, and have similar performance. There is something driving up the cost we haven't been told.

The next obvious question is how much of the cost is software, and how much of that (possibly including the OS) is required cost? The old "easier if they're all the same" argument is usually made by a salesman or lazy purchasing agent, and often doesn't match reality. Data entry jobs which are poking numbers into web forms or spreadsheets don't require proprietary software. That doesn't mean that there may not be some need for commercial software, just that there's a lot of tasks in most enterprises which don't. And the "retraining cost" FUD is just that, people doing data entry, or any activity where the browser is the computer, need to learn login and start application from a menu or icon. Just like Windows. And free software will read/write most proprietary formats, so the need for a proprietary data format doesn't mean proprietary software is necessarily needed. One size does not fit all, there is probably room for saving in software, too.

This might even be a case for thin clients and a few servers, and get the cost way down, not enough information to guess, but a possible large saving. The problem is convincing management that the best approach is finding the most cost effective solution, not in finding the best price on the "way we always did it."

about 4 years ago
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Internet Dismantling the State Church In Finland

WindShadow The Internet as a weapon of mass destruction (547 comments)

Okay, I admit I don't know if the Finnish state church service is called a mass, but the term was irresistable.

about 4 years ago
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4chan finds Linux kernel flaw for attacks

WindShadow Is this new? (3 comments)

Is this the same bug reported days ago and patched before it went public? And which requires being able to execute code on the machine in the first place? This one? Kind of old news if so.

about 4 years ago
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Irish ISP Wins Major Legal Victory Against Record Companies

WindShadow A Victory? Perhaps not (96 comments)

I am not a lawyer, but just because there is no precedent in law, doesn't mean a new law can't be binding, does it? If there was precedent that it was not allowed, that would be a strong argument, but a law requiring a remedy for a crime which didn't exist until recently is bound to have no precedent.

Perhaps some lawyer could explain this leap of logic. There's no precedent for fining or jailing people for sending spam, posting kiddie porn, or cyberbullying, either. Does that mean there can't be? Is this a quirk of Irish law or just a poorly written story?

about 4 years ago
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Visible Light 'X-Ray' Sees Through Solid Objects

WindShadow Re:Visible? Opaque? (122 comments)

There are very few opaque objects, people are translucent. A small percentage of photons manages to pass through without hitting anything which will stop them. Both intensity and frequency (color) deliver information.

BTW: there's some prior art on this, Dr Jerry Tiemann had proof of concept going prior to 1993, at GE's Corporate Research Center. GE Medical Systems declined to fund development. I believe he was using an algorithm developed by Dr Glen Row for transforming fan beam data to parallel beam, to produce more resolution with less computation. Jerry was disappointed that GE was putting resources into cold fusion at the time, instead of photon imaging. Yes, that's the father of Michael Tiemann, the Redhat CTO.

about 4 years ago
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Can We Travel To That Exciting New Exoplanet?

WindShadow No mass required (662 comments)

"One scientist puts the travel time at 180,000 years based on current space flight technology, while another explains that it could be quite quick if we build a matter-antimatter drive, and can figure out how to bring along 530 times as much mass in fuel as is contained in the ship and cargo itself."

As this article explains, there's new science afoot, and propulsion need not require expulsion of mass any more. Note that energy would still be needed, and the technique needs to be engineered up from the current proof of concept stage to an actual ship, but the need for big mass may be gone.

Since the acceleration is based on mv=mv, accelerating low mass particles to very high velocity might offer a very high thrust to mass ratio. In other words that "530 times" is open to improvement if higher exhaust velocities are used.

The real limiting factor is how much acceleration the payload can take, and what your target top velocity (cruising speed) will be before braking starts, and of course available energy regardless of mass requirements. Assuming Vmax of .5c gets to the destination in a lifetime, but doesn't get data back. If entangled particles could be used to pass data, the requirements would no longer include return hardware, and results would be in quickly. Interesting speculation. Of course there are nearer systems, and while ideal planets haven't been seen, they could exist and would be currently undetectable.

about 4 years ago
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Senate Votes To Turn Down Volume On TV Commercials

WindShadow This will break commercial killers (625 comments)

This will make commercials harder to identify automatically, not that anyone would use that to drop commercials, of course.

However, not to worry. Note that the House and Senate passed different bills, allowing them to say "we are protecting you" at election time. If you think they will resolve the differences between the versions and actually pass any law, then you are pretty gullible. And if such a bill were passed and signed into law, the Supreme Court would probably rule that volume is part of Freedom of Speech, just like money, even though my version of the amendment doesn't include any right to make me listen.

On a related note, I see that politicians can bypass "do not call" if you ever voted, since that now counts as a "prior business relationship." I get calls from parties I never joined, and they assure me they have the right. My right to blow a whistle in their ear is protected, too.

about 4 years ago

Submissions

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Facebook blocks KDE Apps

WindShadow WindShadow writes  |  more than 3 years ago

WindShadow writes "I see that Facebook has banned use of KDE apps such as Gwenview, but they seem to have taken down all the photos ever posted with them. Article includes a lovely rant against trusting Facebook."
Link to Original Source
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Thyroid hormone analogue may replace statins

WindShadow WindShadow writes  |  more than 4 years ago

WindShadow writes "A thyroid hormone analogue might be available in a few years to enhance the lipid benefits of statins, or even replace them in patients suffering from statin side effects."
Link to Original Source
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Clans of the Alphane Moon

WindShadow WindShadow writes  |  more than 6 years ago

WindShadow writes "In a recent article which mixed Microsoft, Asperger's, and Phillip K. Disk's Clans of the Alphane Moon Martin Heller talked about developers who can't stop working. In the 60's we called them "closet cases," people so strange you kept them in the closet and fed them through the keyhole. Now we use terms like Asperger's, which is PC, but doesn't reflect how strange some of these people are."
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WindShadow WindShadow writes  |  more than 7 years ago

WindShadow writes "The recent article on the "Fastest Waves Ever Photographed" led to another means of particle acceleration in short distances. The DOE labs at Berkeley boost electrons using laser bursts through plasma."
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WindShadow WindShadow writes  |  more than 7 years ago

WindShadow (977308) writes "I guess I'm missing the point... IBM is all excited at a better way to use thermal grease to cool CPUs, so they can be "smaller and faster." Isn't the objective to make them use less power?

I just spent 12 years (on a ten week contract) working in a big data center, and power use was a constant issue. Intel and AMD are making the CPUs deliver more performance per watt, and I'm really dubious that better cooling is going to be a big deal.

I'm old enough to remember SOS (Silicon On Saphire) and chips on diamond to get better cooling. I'm pretty sure the answer is not in more cooling, but in less power.

"

Journals

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Misuse of technology

WindShadow WindShadow writes  |  more than 5 years ago

I just noted in a reply that and useful technology will be misused, often before the beneficial uses become widespread. And in some cases instead of beneficial uses ever becoming widespread.

I was talking about molecule cloaking, useful to ignore contaminants in a sample analysis, but P-to-P file sharing comes to mind. It seems in France that any software created, even for a legitimate purpose, is your liability if it is misused. I fail to see how any car companies or wineries exist there, since their products are misused in a common and highly visible way.

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IBM is using better thermal paste - so what?

WindShadow WindShadow writes  |  more than 7 years ago I guess I'm missing the point... IBM is all excited at a better way to use thermal grease to cool CPUs, so they can be "smaller and faster." Isn't the objective to make them use less power?

I just spent 12 years (on a ten week contract) working in a big data center, and power use was a constant issue. Intel and AMD are making the CPUs deliver more performance per watt, and I'm really dubious that better cooling is going to be a big deal.

I'm old enough to remember SOS (Silicon On Saphire) and chips on diamond to get better cooling. I'm pretty sure the answer is not in more cooling, but in less power.

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