It became obvious / accepted wisdom that a moderately successful startup exit is the only way to have a decent future as a living person.
This used to be only one of many paths available to a nerd, but now: (a) academia is dead thanks to overly competitive publish-or-perish set-up (probably the biggest loss of the three), (b) corporate jobs do not pay enough to safely survive downturns that leave you jobless for extended periods, (c) government jobs have been made even more onerous and even less paying in real terms.
So everyone has to become a self-promoting, trend-chasing startup-founder type. Even if you don't found a startup, you have to be always ready for a new "business opportunity".
Neat! What do you think about adding a "-2, -1, 0, +1, +2" agreement scale to each quote and showing the average instead of votes?
I think many of those are pretty subjective, and maybe not always right for everyone or for all time. But there are certainly going to be some universal pearls of wisdom, and neither of us can - by ourselves - tell which ones they are.
Is that ever true! I wrote a whole Medium article[0] about this, one of my most popular. It's called "YOU ARE BUGS" as a joke from Three Body Problem on Netflix.
Tubes can also just be very _clever_ in a way that transistors generally are not. For instance, counting tubes that would contain a decimal counter in a single glass bubble (that's quite a few transistors even in TTL, and about twice as many in CMOS). Multiple approaches to building such tubes existed. This is one:
That RAM component is wild. Do you know if there are any equivalent analog RAM components today? By which I mean RAM elements that are similarly capable of storing an analog as opposed to a digital signal.
I don't think I've seen anything sufficiently RAM-like. The classic sense amplifier architecture tends to make this impractical. I guess modern Flash can store a few levels but that's a far cry from actual analog storage.
For a while, you could get things like bucket-brigade CCDs for analog signals (used for reverbs and suchlike). They're still made in small quantities, I think, by boutique operations like Xvive.
Also, there was the ISD ChipCorder, which was actual analog Flash. (Current devices are digital, but the old ones were for a while sold as "MLS ChipCorder" by Nuvoton.)
Pretty good detail in this article! But what really surprises me is how some ideas just keep coming back.
When I wrote a binary translator, I ended up having to keep a translated return stack to optimize RET opcodes. That put me in exactly the same position as the Win16 kernel with regard to having to patch pointers (in case of Win16, just the segment part) on stack.
Of course I did not have the benefit of my guests calling a lock function, so I ended up having to run a garbage collection operation to determine which pointers are in use & take exceptions on now-invalidated segments. Lots of extra work that Windows didn't need: it's nice to be king :-)
That was a fun site to browse. I really enjoy fixing / hacking on non-disposable equipment (lab, test, optics, etc.) and there are some well-done write-ups in there.
I think it's an attempt to express that the station consists of only two segments: Russian (ROS) and US (USOS), but the US invited its allies to work together on its segment. So parts of the USOS are made in Europe, Canada and Japan, and generally lifted to space by the US, usually on the Space Shuttle.
(All this was pretty lucid of the US, but obviously the Russians did no such thing on their side. The Japanese even managed to get an ISS resupply mission launched on their own vehicle, which is no small achievement, and the ESA did a bunch of good science. And what would space be without the Canadarm :-)
USSR, yes. But the ISS was launching during a time when USSR no longer existed and Russia was fairly isolated. Hence, "obviously": US at that time had many close allies, but Russia had only a few, and not as technologically advanced.
Quite the opposite, the West welcomed weak and crumbling Russia. To a limited extend, of course, but still Russia joined G7 and many European organizations. Western companies were busy buying privatized Soviet assets pennies on the dollar.
Actually this chip does have ECC on many of the SRAMs - hence the bit widths of 36 bits instead of 32 in many cases. If it's a concern that the ECC is being used as storage, I'd suggest a laser glitch on the SRAMs to confirm the disturbance is caught by the ECC logic. This would at least confirm that the ECC bits are being used as some form of ECC. We've done testing to confirm the ECC function, but you don't have to take my word for it, it's a thing you can verify, too.
This check would not rule out the possibility that maybe there is some further back door that perhaps at runtime turns off the ECC function and then starts using the bits as storage, but one would need to hide the trigger for this somewhere, and there would need to be a non-trivial amount of logic to perform multiple accesses to the RAM to stripe e.g. executable code across the ECC bits. Specifically, you'd have to do 8 reads to put together a single 32-bit word in the case of a 36-bit wide RAM, which creates a fairly sizeable timing and power side channel.
If the ECC is confirmed (via glitch or sidechannel) during the trusted-boot measurement phase, and all the code and data space is accounted for, then the alternate mode trigger would then have to be in hardware. In either case there would be a non-trivial logic disturbance in the surrounding gates compared to the reference design (this is assuming you're trying to differentiate between a "good" design and a "modified" design).
To be clear, the article states that optical inspection alone can not yield a perfect security bound. However, it reduces the attack surface from an essentially unbounded problem, to a set of more difficult attacks such as the ones outlined above, which once enumerated can be detectable via other means.
This is a much stronger bounds than chips that are impossible to visibly inspect, and thus can trivially hold several kilobytes of fast code storage that can be easily swapped out and run at full speed, leaving little to no side channel to detect, and an intractably large space to search via software-only brute force for discovery.
Re: repair rows - these are a valid place to hide data, but in this design there are no repair rows, and you can confirm they don't exist from the imaging data.
This is very interesting, but would you tend to agree that at some point the effort to adversarially inspect to verify becomes larger than the effort to make something like SRAM oneself?
The effort of fabricating yourself dense CMOS integrated circuits, instead of giving your design to a foundry, to have it fabricated there (where a malicious foundry could modify the design), is huge, even when you do not want a state of the art technology (which would require billions of $).
Here, the description of how an end user could verify what a die contains is intended to guard not only against the possible modifications done by a malicious foundry, but also against a dishonest designer, who could claim that the chip contains something, which is shown in documentation and in the part of the design files that are open source, but the real design could include something else.
Hacker News is still skewed towards people interested in programming languages (as opposed to actually programming). Probably some sort of Y-combinator Lisp heritage. There's also a persistent minority of CS grads who think that developing / using new programming languages is the most fascinating thing in the world, and some of them hold on to that thought.
It's reasonable that such people would also be interested in design aspects of languages, and UB in C is in that field. Though I would argue that a lot of it was originally accommodating old CPU architectures without compromising performance too badly, and about as much a "design choice" as wheels being round...
There was also a period around the mid-2010s where I had the strong impression that lots of younger ambitious devs were fanatically promoting rust against C's undefined behavior mostly because it gave them a way to differentiate themselves from older seniors within organizations. (And I say this not as an old C diehard, but as someone who watched more than one colleague position himself as the 'rust guy'.)
If you don't have space for a microscope, you can also get yourself the long-range (~400mm) 2.5-3.5x magnifiers that you may have seen your dentist wear. They're easily available on Amazon, not too expensive, and comfortable for hours of wearing. These are 2-element lenses that work really well.
Higher magnification variants (8x etc) are not nearly as comfy. They get quite long, heavy and expensive. I tried them and did not like them nearly as much. Also beware of short viewing distance, ultra-cheap products that are just a single lens element per eye.
I have a Donegan DA-5 OptiVisor Headband Magnifier. They're nice, because the lenses are prism'd so that you can focus on something close without having to go cross-eyed.
No problem! The only helping hands I'd recommend are https://omnifixo.com/. Pricy, but everything else I've tried has too much play and is useless to me. Omnifixo is just fantastic.
This used to be only one of many paths available to a nerd, but now: (a) academia is dead thanks to overly competitive publish-or-perish set-up (probably the biggest loss of the three), (b) corporate jobs do not pay enough to safely survive downturns that leave you jobless for extended periods, (c) government jobs have been made even more onerous and even less paying in real terms.
So everyone has to become a self-promoting, trend-chasing startup-founder type. Even if you don't found a startup, you have to be always ready for a new "business opportunity".
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