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Bit flips are real. I used to see them on my (admittedly low end) webserver. Eg. There were occasional errors like "myOfunction not found". A quick glance on a ASCII table shows that the original function name "my_function" is indeed one bitflip away (0x4F vs 0x5F)
Earlier quoted context omitted.
Could physicists and astronomers use all this distributed particle detection for research? Like a app in a phone or desktop that sends reports back with location and time information.
Most bit flip events are apparently due to alpha particles from radioactive decay in the package (source - worked for a company which used 'low alpha compound' in some of our ICs to put off having to implement HW error correction) , which would be a big confounding signal. I imaging physics experiments work hard to avoid this, or at least correct for it.
Invalidating the caches is kind of a cringe inducing approach on this (actual) problem. Especially in HPC radiation related single event upsets have become a real problem. If you do the math, all the silicon area devoted to memory (DRAM, caches, registers) adds up, and what you've got is essentially particle detector. Compared to the effective volume of a purpose designed one (ATLAS, CMS, Super Kaminokade, etc.) rath…
Could physicists and astronomers use all this distributed particle detection for research? Like a app in a phone or desktop that sends reports back with location and time information.
I don't know if any novel results have come out of this kind of thing.
Of course cosmic rays don't exactly leave a trace, so we will never know.
If you don't believe in bit flips, try this! http://dinaburg.org/bitsquatting.html I did that for a bit on cloudfront.net and got dozens of them in a short amount of time.
bitflips are also single char typos in ascii. I'm guessing that is what you saw
1. Not all single char typos are bitflips and when you test it statistically you get more traffic for bitflips than typos. It's a bit more complicated, some typos are really common because they're close to the key.
2. You can look at the raw traffic that comes in and tell what is a simple get request with a fat finger (GET https://en.7ikipedia.org/ vs GET https://en.wikipedia.org/w/index.php?search=america&title=Sp...).
Source: I have some domains that are bitsquats of some high traffic domains. I get access token headers when I do a raw dump of the traffic. (I turned off the servers after satisfying my curiosity.)
Want to stop randos from getting some tiny portion of your traffic's access tokens? Use client side keys and send signed / encrypted access tokens or even full requests.
Yeah I know. It's so far down the list it doesn't matter. But every combination of github.com, microsoft.com, etc is bitsquatted, so this attack can be considered ongoing. This is doubly true if you're on a domain like .co.uk which is a stupid subdomain of .uk and now that .uk addresses are available someone can buy ko.uk and bitsquat the entire fucking country.
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> Bit flips in network surely is many orders of magnitude worse Yes, but because it's so prevalent that people expect it, they've added checksums on multiple levels, so the network actually performs better. In this particular instance (DNS queries), it's very unlikely that the data was corrupted in transit: "We believe that UDP checksums are effective at preventing 'bitsquat' attacks and other types of errors that oc…
That doesn't take into consideration of flaky home-routers (note that they do recalculate the checksum). So the checksum might be processed on bad data. For a bad connection it will also be quite common that the checksum will happen to be valid. TCP/UDP checksums are quite bad.
If you don't believe in bit flips, try this! http://dinaburg.org/bitsquatting.html I did that for a bit on cloudfront.net and got dozens of them in a short amount of time.
Bit flips in network surely is many orders of magnitude worse than in cache/memory bit flips? And I doubt it has to do with gamma rays. Those with poor or long distance DSL do see a big increase in errors. And while hopefully getting rarer now home routers could easily overheat and introduce errors as soon as they saw more than usual traffic. We recently had issues with the power supply for our router and it also cau…
A bunch of years ago Cisco had an issue with some RAM in a new switch model, I think it was in the 65xx. They where crashing randomly but only in certain places in the world. Cisco spent tons of money on this. No idea. They brought in a physics professor. The devices with the most issues were located in countries up near the artic circle. Cosmic Rays caused a bit flip in this particular set of RAM due to something in…
I knew big customers (such as Cisco) can ask for such test reports and they do get it.
It would be very interesting experiment to position some modem/old (7, 14, 28 nm chips) electronics (cell phones, raspberry Pi + solar panels) to various distant near nuclear accident site, monitor them remotely, classify and log the failure rate over the months/ years.
If you don't believe in bit flips, try this! http://dinaburg.org/bitsquatting.html I did that for a bit on cloudfront.net and got dozens of them in a short amount of time.
bitflips are also single char typos in ascii. I'm guessing that is what you saw
If you don't believe in bit flips, try this! http://dinaburg.org/bitsquatting.html I did that for a bit on cloudfront.net and got dozens of them in a short amount of time.
Did also that with facebook.fr/google.fr/akamai.net domains. Got a _lot_ of hits, with mostly mobile user agents. Was fun; never published my results though..
Get a tls cert and you might even be able to serve the original file with some additional js of your own :)