Bitcoin Forum

I have only a beginner's understanding of encryption, so please bear with me. It was explained to me once that PGP encryption would take a long number of years to break with commonly available computer equipment, but that if, say, the NSA really wanted to crack somebody's encrypted message, they have quite advanced computers that would be able to do it in a less than ridiculous amount of time. Say, a few months.

Is this true? And if it is true, would the NSA be able to break Bitcoin encryption and therefore destroy the value of bitcoins if they really wanted to? Or is Bitcoin better protected than PGP?

That might be the case with SHA-1 and RSA/DSA-1024 (used by default in old versions of PGP), but the SHA-256 and ECDSA-256 algorithms used in Bitcoin can't be cracked in any reasonable time with current technologies. NIST believes (http://www.keylength.com/en/4/) that these algorithms/keylengths will be strong past 2030.

To break PGP you have pretty much no time limit, you can keep chugging away until you crack the encryption. To break bitcoin you have to do it before the next block is generated, because once it is then you need to crack the new block before you can break this one.

Afaik, the NSA is able to break a 512-bit encryption. But the efford to do this is just huge, so this usually doesnt happen as long as your name isn't in that list: The Joker, the Green Goblin, Lex Luthor, Palpatine, Magneto and Doctor Doom.

And still it would take months to finish.

Just what I've heard/read.. doesnt mean it is correct.

It is not true. NSA have the same computers as everyone else. They have to buy their chips from the same manufacturers. And anyway, finding a single SHA-256 hash collision, say, by brute force with all the computing power in the whole world would take something like a hundred trillion trillion trillion trillion years.

If the government knew a secret algorithm that allowed it to break encryption faster than anyone else, that algorithm wouldn't stay secret for long, given the government's dismal record on securing data.

I would not underestimate the manpower, money, time or resources available to the government.
meaning they have technologies far beyond our comprehension, so really who's to say that they can't or can.
 

You are not taking all circumstances under consideration..

And the most important one is: QUANTUM COMPUTERS.

The goverment always has everything much faster than the rest of the world (example: they had Internet at least 10-15 years before the public). Scientists currently say, that quantum computers are a matter of 10 years. So what if government is 10 years ahead of everybody else, and they have the Quantums already ?

I think this possibility should be SERIOUSLY taken into consideration. Perhaps the length of bitcoin cryptographic keys should be increased 10-fold to account for that (but this won't be enough to protect us from quantums anyway, so that may be actually pointless).

EDIT:
However, increasing the length of crypto keys 10-fold would surely postpone the inevitable downfall of all hashes & current cryptographic algorithms in case of quantum comps are invented. That would give us bitcoiners more time to adjust & perhaps invent some defense.

Such an hypothesis is a bit too big for me.  I doubt it complies to Occam's razor.

Also, quantum computers would make quantum cryptography easy.

So it would kill bitcoins, but would allow the arrival of a quantic cryptocurrency, which would be absolutely unbreakable.

What kind of harm one could do by breaking cryptography in a super-speed like the scenario suggested?

AFAIK, the block building is a process of cryptography breaking itself. So, if the "enemy" could gather more processing power than the entire honest network, s/he could generate his own block chain where s/he could undo some past transactions and cause other troubles. But, even for the government, it sounds too much of computing power.

Another thing they could do is try to break the private key of someone. That would be an attempt of stealing... it doesn't sound profitable since people rarely would have too much money under one same private key, and if it takes months to break it, the money will probably change keys before that.

Besides running a parallel block chain or stealing someone's money, what else could be done with a super-key-breaking-computer?

Given that scientists cannot create much of a quantum computer, I don't see how the government can possess that kind of technology.

The short answer to your question, "can the government crack Bitcoin encryption within a couple of months?" is both yes and no.

Yes, because we should assume the US government (or someone else) does have the resources to accomplish this within the timeframe.  It's actually unlikely, due to the degree of resources required, but it's best for us to not assume that any single security feature is unbreakable.

No, because those resources are nearly always in demand from multiple agencies, and spread across multiple agencies with multiple missions to begin with.  Neither the Federal Reserve nor the US Treasury has any direct access to these kind of resources.

But you need not worry about it, for several reasons.  First, they could only "crack" one address at a time, and as has been mentioned by others, could expect little for the effort.  All that they could do with that information that they could not already do by datamining the blockchain is transfer the funds associated with that particular address.  It would tell them nothing at all about who the address belongs to.  There is, intentionally, no message data that is managed by Bitcoin; so no messages would be laid bare for the efforts.  No information means no motive, at least no motive beyond petty theft.  Also, the very nature of Bitcoin ensures that the odds are high that even if someone mined the blockchain and identified a single address with enough coins to be worth the effort, they would likely be transfered out before a couple months had passed; as every transaction empties the address from which it came and generates a brand new address to receive the balance.

Be careful, because the price for thinking that You know what exactly is going on and being wrong is terrible.

I really wouldn't be surprised if government alread had working prototypes of quantum computers. If they have, bitcoin surely comes next (after decrypting russian/iran/political enemies' hard disks) in line to be busted.


The main grip the govern.m-ent (read: F-E-D) has over people is the money supply. If they start to lose that grip, be sure they will invest every possible resource they have, to save it.

Don't be foolish - if bitcoin really becomes a threat to them, they won't hesitate to use quantum computers (if they have them), ban bitcoin usage, ban T-O-R usage or even call a terrorist & send to g.u.a.n.t.a.n.a.m.o every single person who uses any of this technologies. Bah, they even may shut down the internet (law just for this have been passed already) just to take care of that single threat. Yes, I'm serious.

EDIT:
BTW,
I don't know if You realize, but the hegemony of U-S-A comes mostly from controlling money supply of the world through Oil (as Oil can only be bought for dollars). They use dollars as a way of collecting tax from the rest of the world using ever-inflating currency, but that's another long story.

The point is, g.ove-rnment will never, ever let anyone take that power away from them. This is even more serious than with oil. They would actually repeat it all over again: attack a country, torture & kill innocents or even kill its own citizens just to take down a threat to the d.ol-lar currency...

http://eprint.iacr.org/2010/006 (https://web.archive.org/web/2010/http://eprint.iacr.org/2010/006)

I think that you give them too much credit.  First off, no government is a monolithic entity, all working in unison for some grand agenda.  Second, the passing of that silly law is one thing, practical enforcement is another.  Personally, I don't think that it's possible to 'shut down' the internet; by fiat or otherwise.  After all, it was designed to be *bombed* and continue to function.  

And your attempts to avoid govco's internet traffic filters just make me laugh.  I know, for a fact, that the US government has had the capacity to record the entire electromagnetic spectrum from anywhere in the US and anywhere that a US base or embassy exists since the 1970's.  Granted, I can do the same thing today with a relatively recent GNU/Linux desktop, GNUradio and about $500 worth of specialized electronic hardware; but this was forty years ago!  I have no doubt that the filters used on the public Internet are smart enough to get past your little tricks.


Yes, I am aware.


Who is "them"?  You seem to assume that there is a grand cabal running the show, when such a collective effort, with a secret kept for decades if not generations, is not really neccessary.

The truth is we don't really know for sure and even if we did know I think we wouldn't be allowed to tell you. Of course there is no limit to the speculation.

All we can really do is proceed with what we do know and hope the secret organizations are not too far ahead. We can only take some consolation that the secret groups do not really have unlimited resources, they are constrained by finite (tho perhaps large by our standards) budgets, time and personnel.

Things are going to collapse before they get a chance to target bitcoin

http://www.youtube.com/watch?v=RPSJDqx4Dq4 (http://www.youtube.com/watch?v=RPSJDqx4Dq4)

Nice topic here everyone has to see this and be confident in Bitcoin.

Government breaking encryption is rare, and not really possible, not that they can't break encryption bit it will take a longer time to get it right..

Super computers around the world are unable to break bitcoin's security so it is unlikely that the government will have anything more than that. If they could break this solid encryption then they would go after bigger projects than bitcoin and the digital world (e.g. online banking) would have to shut down

Its said that it would be possible if Quantum computers come in to existence.But it would almost take 20 more years for it to come in to existence.So no need to worry about that immediately.But also,work is going on to promote it.

The question is even if the goverment already has the ability to break crypto encryption would they risk revealing it just to get some bitcoins? I mean wouldn't it be better for them to keep it secret, using it for the real threats and risks?

BTW I think we will see quantum computers way earlier than 10 years form now, so it is possible that gov may already using it.