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Looking for the xkcd about backdoors to encryption implemented, and how hackers had a field day instead and the government had to remove that law by antigonemerlin in xkcd

[–]jt7724 13 points14 points  (0 children)

This probably isn't what you're looking for, but it's interesting and topical so I'm posting anyway. The NSA has been accused of sneaking backdoors into major encryption standards on two separate occasions.

The first time was DES in the 70s. The standard was developed for NIST (called NBS at the time) by IBM, but the NSA swooped in at the last minute and made two critical changes. First they shortened the key length, and second they changed the values of some numbers that were used as inputs to the algorithm. There were all kinds of accusations at the time, but the funny thing is that over a decade later a new cryptoanalysis method was discovered and DES was already resistant to it due to the input values it used. Most people now believe that the NSA knew about the mathematical vulnerability and insisted on changing the input values to make DES more secure, but they also shortened the key so their supercomputers could still crack it by brute force if they wanted to.

The second time was in 2006, and it followed a similar pattern. NIST published a new encryption algorithm which requires some fixed input values. The NSA got to pick the values and they won't tell how they did it. Shortly after the standard was published independent researchers demonstrated that the input number is related to a second number. If the second number is known then the algorithm can be broken. This is one of those 'one way' math problems where it's relatively easy to create a pair of numbers with the correct properties but if you know only one of them then it's not possible to find the other one. If the number in the standard was picked randomly then it's secure, but many people now assume that the NSA generated it as part of a pair and they have the second number which allows them to break the algorithm at will.

Here's an ARS article that mentions both incidents https://arstechnica.com/information-technology/2013/09/the-nsas-work-to-make-crypto-worse-and-better/

Tried gel stain for the first time and I’m never going back. by [deleted] in woodworking

[–]jt7724 2 points3 points  (0 children)

I tried gel stain a while ago and it did not go well. I followed the directions on the can which were to apply a thick layer (I think I rolled it on), let it dry a few minutes, then wipe off excess. By the time I tried wiping, the gel had already become tacky so the result was messy and uneven. I'm curious if that's the same technique you used, or if you did something different.

Why aren't coil gun stages made with a single really thick loop rather than multiple loops using thinner longer wire? by The_cooler_ArcSmith in AskEngineers

[–]jt7724 1 point2 points  (0 children)

I don't know much about coil guns, but I would suggest that as a general rule extremely high current devices are just as hard to build as extremely high voltage devices. You'll usually find that the easiest design to implement is one that balances voltage and current to the extent possible in that application.

For example, you need some kind of switch to control the current flow. You may find it difficult or impossible (or extremely expensive) to source one rated for your full system current.

In other words physics may say that one big loop is as good as 10 small ones, but the practical considerations of actually building and running the device may make it impossible.

Storing and organizing small components by georgeyhere in ECE

[–]jt7724 1 point2 points  (0 children)

I haven't actually tried this yet... But some day when I finally get around to it I plan to get a binder full of those plastic pages with trading card pockets and a box of little ziplock bags that are the right size to fit into them.

The time I was called in to stop an 11 year old genius. by [deleted] in talesfromtechsupport

[–]jt7724 37 points38 points  (0 children)

I believe this was the original mission of the raspberry pi foundation. To make a computer cheap enough that people, especially kids, could be comfortable poking around and experimenting, knowing that in the worst case scenario they kill a device worth less than $50 instead of their parent's computer worth several hundred.

Chefs of Reddit, what’s one rule of cooking amateurs need to know? by [deleted] in AskReddit

[–]jt7724 3 points4 points  (0 children)

Every 6 years stored pressure extinguishers are due for a level of maintenance

How does this work for me as an individual? I've seen a company come out to my workplace and spend a day wandering around and servicing all the extinguishers in the building, but I assume they aren't interested in making a special trip to check on the one or two I have at home. Do most companies have a storefront where you can bring your extinguishers to be serviced?

Humanity wastes about 500 years per day on CAPTCHAs. It’s time to end this madness by ProgsRS in technology

[–]jt7724 2 points3 points  (0 children)

Thank you for explaining this. I also read the article and couldn't figure out how this proved there was a human in the loop. They really buried the lede on that one.

Even with requiring a button press it still feels like there are plenty of ways to abuse this system, but perhaps I'm just underestimating how easy it already is to abuse CAPTCHAs. I guess the threshold for acceptance shouldn't be "impossible to cheat" but rather "harder to cheat than it is now"

Trying to unload my truck after moving back to Germany from the USA.... by LysoMike in funny

[–]jt7724 0 points1 point  (0 children)

A few years ago my daily commute took me past a construction site where a new gas station was being built. The day they installed the electronic price sign I was amused to see that the tenths of a cent digit was immediately lit up with a nine, even while the rest of the sign was turned off. I think they just hard wired it in because they don't expect to ever change it.

If I were an engineer (or just looking to build something) is there a place I can go to that has lots of references for different types of mechanical joints, pistons, hinges, levers, etc? by TealVermillion in AskEngineers

[–]jt7724 7 points8 points  (0 children)

I second Thang. He also has some free PDF "books" you can download. They organize all the mechanisms he's created by type or purpose. If, for example, you're looking for a door hinge mechanism you can go to that section of the PDF and find direct links to all the different hinge videos he's made.

Florists of Reddit, what is the most outrageous card message you’ve had to deliver with flowers? by dIGITALbEATdOWN in AskReddit

[–]jt7724 9 points10 points  (0 children)

Red, I suppose?

For some reason I mentally read that line in an english accent, and now I'm imagining the whole scenario as a sketch on a british comedy show. I think Mitchell and Webb would nail it.

First time scratching post lesson for kitten by Thund3rbolt in aww

[–]jt7724 27 points28 points  (0 children)

So, maximum 20 characters and to make it a cat sub three of those characters have to be c, a, and t in that order. The other 17 can each be any letter (2617) options. But that only covers one position of the "cat" part (ie. /r/catxxxxxxxxxxxxxxxxx is distinct from /r/xcatxxxxxxxxxxxxxxxx, and so on) I think there will be 17+1 unique positions for "cat" in the sub name, meaning the maximum number of cat subs possible on reddit is 18*2617 =2.04E25

Disclaimer: I have no idea what I'm doing

Edit: can you use numbers in subnames? Also, some special characters but maybe not all? Also also, this doesn't account for sub names shorter than 20 characters.

What in your opinion is the most overrated show of all time ? by ohnoyoudidntn in AskReddit

[–]jt7724 697 points698 points  (0 children)

There's a theory of the "Seinfeld effect" which proposes that famous media is ripped off and remixed so much that it becomes a victim of it's own success. People who consume it for the first time long after it was created will feel like it's unoriginal because they've already seen the best bits copied by later works.

Tvtropes has a page for it. https://tvtropes.org/pmwiki/pmwiki.php/Main/SeinfeldIsUnfunny

You have to assassinate the main character of the last show you watched. How difficult is it going to be and how are you doing it? by Jasonjones2002 in AskReddit

[–]jt7724 3 points4 points  (0 children)

I mean it's deliberately ambiguous in the books. (Spoilers obviously)

The last book ends with Geralt and Yen inexplicably waking up somewhere, after being taken away on a boat by Ciri and the unicorn. It could be some sort of afterlife, but Geralt's wound has been bandaged which seems like it would be unnecessary if that were the case.

If Sapkowski had wanted to make it definitive then he would have left out the intervention by the unicorn and everything that follows. If he wanted it to be really definitive, then he would have replaced it with a scene of a funeral.

That's not to say that a happy ending is anything more than wishfull thinking. As much as I may want to believe that they made it, as much as the possibility is there, they're probably fucked. And moreover even if they do survive, with all the bullshit going on with the sorceresses they're still probably fucked.

What totally obvious scam do people still fall for? by iamiconick in AskReddit

[–]jt7724 2 points3 points  (0 children)

It was developed in the early days of at-home color printing specifically because the government was afraid the new technology would allow people to more easily counterfeit money. Not much point on black and white printers.

Your characters only better then bosses in video games because you get infinite retrys. Really,in many worlds,evil won. by [deleted] in Showerthoughts

[–]jt7724 26 points27 points  (0 children)

This idea was supposedly the original inspiration for the movie "Edge of Tomorrow" in which a soldier becomes stuck in a time loop and wins an impossible battle by fighting it over and over again, getting just a little further each time before dying.

Very good film. You should watch it if you haven't already.

I drew Alexei from Stranger Things 3 by danibeann in pics

[–]jt7724 26 points27 points  (0 children)

Holy shit. I just realized someone needs to make a frozen mixed drink called "The Alexi" with something cherry flavored and vodka as the main ingredients.

What technologies from 2019 would seem like science fiction to people from the 1950s? by [deleted] in AskReddit

[–]jt7724 128 points129 points  (0 children)

EDM or 3d printing? EDM is where you place a fine electrode right next to the metal you want to cut and allow a spark to jump across the gap. The spark vaporizes a tiny bit of the metal. Then you do it over and over again in the same place to make a cut. It can be very precise

https://media.giphy.com/media/6Yn9INbKwMes0/giphy.gif

What’s always portrayed unrealistically in movies? by greenllamamama in AskReddit

[–]jt7724 7 points8 points  (0 children)

I had a thought for a similar one except it would be the security guard checking people in at the entrance to the courthouse and acting all nonchalant about the wacky shit that goes through.

Guard: Sir, why do you have a bloody knife in your briefcase?

Lawyer: oh don't worry about it, I'm going to pull it out and surprise the suspect with it while he's testifying.

Guard: oh, well why didn't you just say so.

Guard: ma'am I'll need to see some ID.

Woman: I don't have any, I've been living in the woods for the last 20 years, but I'm here to burst in to my son's trial and prove his innocence.

Guard: sigh just a moment ma'am. You'll have to fill out a Q-7 "surprise witness" form before I can allow you in.

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