overview for sandman2211

Chinese researchers break RSA encryption with a quantum computer in c/cybersecurity

[–] sandman2211 5 points 1 month ago (3 children)

I think Schneier wrote this well before quantum computers were a reality - did he miss something fundamental in regards to them? Quantum computers are relatively new but the theory behind them is nearly a century old.

*One of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To record a single bit by changing the state of a system requires an amount of energy no less than kT, where T is the absolute temperature of the system and k is the Boltzman constant. (Stick with me; the physics lesson is almost over.)

Given that k = 1.38×10-16 erg/°Kelvin, and that the ambient temperature of the universe is 3.2°Kelvin, an ideal computer running at 3.2°K would consume 4.4×10-16 ergs every time it set or cleared a bit. To run a computer any colder than the cosmic background radiation would require extra energy to run a heat pump.

Now, the annual energy output of our sun is about 1.21×1041 ergs. This is enough to power about 2.7×1056 single bit changes on our ideal computer; enough state changes to put a 187-bit counter through all its values. If we built a Dyson sphere around the sun and captured all its energy for 32 years, without any loss, we could power a computer to count up to 2192. Of course, it wouldn't have the energy left over to perform any useful calculations with this counter.

But that's just one star, and a measly one at that. A typical supernova releases something like 1051 ergs. (About a hundred times as much energy would be released in the form of neutrinos, but let them go for now.) If all of this energy could be channeled into a single orgy of computation, a 219-bit counter could be cycled through all of its states.

These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space.*

I'm not a physicist but quantum particles were still considered to be matter the last time I checked.

China begins launching a megaconstellation, and it sounds a lot like Starlink in c/spaceflight

[–] sandman2211 5 points 3 months ago

Kessler Syndrome, here we come!

I tried to make a phone case. in c/diy

[–] sandman2211 3 points 4 months ago

Looks solid!

I think my home network may be compromised, please advise in c/networking

[–] sandman2211 3 points 7 months ago (1 children)

Do you have any IoT devices chewing up a lot more bandwidth than they should be?

I think my home network may be compromised, please advise in c/networking

[–] sandman2211 1 points 7 months ago (1 children)

The factory reset idea is mostly to clear out any unauthorized customization that may have been made. If you can confirm that hasn't happened then it wouldn't be necessary. I have a router that's not supported by my ISP so I feel your pain. Fortunately I only had to figure out how to tag a particular vlan on the WAN to get it working and someone else had posted a guide that got me most of the way there.

I think my home network may be compromised, please advise in c/networking

[–] sandman2211 3 points 7 months ago (5 children)

Can you get into your router's admin interface? At the very least assuming you don't have much networking experience I'd do these things in this order:

1 - Check for firmware updates and apply them

2 - Factory reset

3 - Change password

4 - Recheck for updates in case the reset wiped them out

There's a million other things you can do to get more info on what's going on and put in security layers to do this and that. But if you just want the maximum results for the minimum effort this is the best place to start.

Did I install this Range Hood Correctly? It Makes a Lot of Noise Due to Some Vibrations. in c/diy