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Comment Re:Practical? (Score 1) 138

I fully understand that but using the brute force attack does provide a good metric by how to judge things and yes I know that in my previous statement I didn't cover more detailed attacks as no one would like to read that wall of text. In response to another user above I look a little more closely at AES-256 taking into account using a quantum computer and the best attack against it. In that case we move from stellar mass energy requirements down to something that would become fairly trivial with a complexity of about 2^50.

Comment Re:Practical? (Score 1) 138

If losing encryption keys is going to be a problem for with crypto that strong then it is already a problem for you as you neither have an ideal classical computer operating near the limit of Landauer's Principal nor do you have the ability to consume a large fraction of the US's total annual energy consumption. The problem is with encryption is that if it is feasable for a state actor to crack it, then it is also possiable for a large criminal gang to do so in a few years, and a few years later you can do so with a device that runs on a battery that you carry in your pocket, see the image in the original article where they point out that generating MD5 hash collisions can be done on your smart phone in about 30 seconds.

Comment Re:Practical? (Score 1) 138

The reason I want crypto that has a chance of surviving the heat death of the universe is simple. Unless you are using a One Time Pad the encryption you haven't isn't provably secure for all time. It will be attacked and the strength of it will decrease. Is my data so important that it personally needs to be kept secure until the heat death of the universe? Simple answer is no, but at the same time it is something that I would like to see stay secure for the next 50-60 years until I'm taking a dirt nap.

So now lets look at AES-256. Here we are dealing with a cipher that is in that mass energy of a star to brute force on an ideal classical computer. Now that may seem pretty damn strong, but there is a related key attack against it that brings that complexity down to 2^99.5 from 2^256. At this point we are no longer talking about star sized energy requirements but instead a sizeable portion of the total annual energy output of a a nation on an ideal classical computer. While currently infeasible further advances in cryptanalysis and quantum computing will decrease this further. So using something like Grover's algorithm we could possibly get the work down to about 2^50. At that level we have already rejected crypto standards because they are easy to defeat.

Comment Re:Practical? (Score 5, Informative) 138

Ever since I read this blurb from Applied Cryptography by Bruce Schneier years ago it has really put things into perspective when it comes to what is strong crypto and what isn't. I got the concept from him so it isn't my own idea even if I did simplify the explanation of it.:

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 3.2K 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 1.21×10^41 ergs. This is enough to power about 2.7×10^56 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 2^192. 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 10^51 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 want crypto that has a good chance of outlasting the heat death of the universe even with a quantum computer. For symmetric key crypto this means you would need somewhere around a 601 bit keyspace IIRC before you exceed the mass energy of the universe.

Comment Re:Practical? (Score 1) 138

Sounds very practical to me. The fact that this is in the realm of being done by a wealthy individual should indicate why. Lets say you are a wealthy criminal gang go out and get your self a bunch of beefy servers and fill them with GPUs. You now can defraud banks and others at a massive scale and probably make the money back in short order. 6500 CPUs and 110 GPUs isn't all that expensive. You could probably get that for $10,000,000-$20,000,000 and next year it will cost even less to get that computational power. The fact that we aren't talking about time or energy requirements that are on the order of lifetimes of stars or the mass energy of a star should tell you that it broken. Also attacks only get better with time. It only took 4 years to go from theoretical to actual.

Comment Re:capacity (Score 1) 48

These things keep on progressing usually following moors law like growth. As others have pointed out 1TB ones are available but they are expensive. My rule is that I will pay about $20 for a flash card or thumb drive which means now I can get a 64GB uSD card for just under $20, a 64GB USB 3.0 thumb drive for about $16, or a 64 GB USB OTG drive for about $20. Some time in the next 16 months I should be able to get 128 GB drives at those price points, and in 18 months after that 256GB drives. If I wanted I could get a 256GB USB 3.0 thumb drive now for about $55 or a 128GB uSD card for about $40. So give it a few more years (3-5 would be a good guess) and the miracle of smart engineers will deliver what you want at a reasonable price.

Comment Re:kill two birds with one stone. (Score 1) 125

I've thought about doing a similar thing to this to defeat ALPRs but it seems that most of these methods don't take it far enough. most of them are trying to get some bleed into the surrounding area of the sensor. A few watts of power draw is nothing which is what most of these attempts do, I'm thinking like 100W power draw for each license plate. I'm looking for this effect but in the IR. So instead of trying to create lens flare I want to massively underexpose the image. In this case I may also get some massive lens flare as well but that isn't what I would have been shooting for. Also using some LEDs like these would be good as they are far enough into the IR that they don't have the red glow that others do.

Comment Re:That's why I pay to recycle monitors (Score 1) 274

don't you know you are suppose to recycle your used motor one quart at a time and the used filter gets its own trip as well. Same things with CFLs and use alkaline batteries. Each one gets its own special trip to the recycling center.

All joking aside I do a similar thing you do. I have a few bins and containers in the garage that hold all the shit I'm not suppose to toss in the trash or single stream curbside recycling and when I run out of storage I make a trip over to the county recycling center. On the way I stop by my in-laws house and pick up anything they want to get rid of and also stop by my mom's house and do the same as they are all on the way. I make the run a couple of times a year and it is only like a 15 mile drive there an back. And before anyone says what I am doing is illegal my in-laws and mother live in the same county as I do so their crap is allowed to go to that recycling center as well.

Comment Re:They are more likely to do what I want if I pay (Score 1) 274

I always like my county's recycling center. When ever I go there I check to see what they have for deck stain and solvents as nothing beats getting free solvents if you clean parts or do lots of wood finishing. Add in that over the years I have gotten 3 unopened gallons of the deck stain I use and it is great. They will take all of the toxic crap, even coolant poisoned motor oil, and if you can use something you can take it.

The city cleanup events are also another great place to find quality trash. I told my uncle, who is a garbage man who works a number of these, to keep an eye out for a nice larger cast iron wood stove for when I finally build a cabin on my lake property. He usually sees one about every 3-5 years so I have a pretty good chance of getting one when I need it for free.

Comment Re:That much demand for being lied to? (Score 1) 202

Apparently you don't understand the concept of reasonable and prudent. No one ever said following rules, regulations and guidelines ensures you are secure but so long as what you are doing is reasonable, prudent and also at the very minimum the industry best practices you wouldn't have to worry about being sued. Granted anyone can sue anyone for fun and profit but by taking reasonable and prudent actions usually defined as a minimum of industry best practices you can avoid losing the lawsuit. A zero day exploit that is used to carry out an attack is entirely possible but is not negligence. An exploit that is 5 years old with a patch has been available for 4 years 11 months and mitigating measures available for 5 years that is used to attack a system that has not been patched and taken mitigating actions is negligence as it would be reasonable and prudent in that time to take appropriate measures to resolve the vulnerability. Where you run into some grey area is there is an exploit that was recently disclosed and a patch or mitigating measures are available. On day 1 of the disclosure it isn't reasonable or prudent to deploy those to productions systems, but at what point is it reasonable and prudent to have done so. In this case regulations like NERC CIP provide a definition of what is a reasonable time so that covered entities can fully test and evaluate changes before applying them to a production system.

Additionally good security regulations and rules will employ the defense in depth principle which will help to mitigate problems if a vulnerability is discovered. Furthermore good regulations require some form of continuous monitoring of the system looking for issues and strange traffic, files, and/or behavior. So you have network firewalls, NIDS/NIPS devices, segmented LANs, host based firewalls, HIDS, a patch management program, following a security benchmark for the host and applications, practice least privileges, have minimal software installed on the host, have a tool scanning your network looking for new devices, have a vulnerability scanner scanning devices and hosts on your network, etc. all provide a good defense and provide multiple layers to stop and detect attacks in different ways. Sadly this cost money and doesn't show a return on the bottom line so it is seen as only a cost center, until there is a breach, so companies don't want to spend on doing what is needed.

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