Bitcoin Network Speed Breaks 1 Petahash per Second | Hacker News Reader

Bitcoin Network Speed Breaks 1 Petahash per Second

thegenesisblock.com

65 pointsgeektips42 comments

So 10^15 H/s is about 2^50 H/s, or 2^71 H/Y.

Assuming you could rededicate the whole network to attacking SHA-1 (which you practically couldn't, the ASICs would need replacing) you could break 2^10 intermediate SHA-1 signed CA certs per year, and compromise the whole current deployment of HTTPS.

Assuming that the hashes are equivalent difficulty (I don't know if they are): Given that the market cap of Bitcoin is ~$1B, imagine what you could do if you had ~$1-200M and wanted to crack some certificates...

And now we know how NSA "breaks the internet encryption", it is not through RDRAND, its by good old force. Its much more cost-effective to do things by force than trying to predict the future uses of some hardware with some special software.

Your math suggests that you can break a certificate with 2^61 hash operations, but this page says 2^61 operations will only give you a collision:

https://code.google.com/p/hashclash/

With the ability to generate collisions, it becomes easier to trick a CA into signing an evil certificate, but collisions don't help if you want to break someone else's certificate.

By "break", ctz meant "create 2^10 certificates". Creating arbitrary intermediate CAs would indeed compromise the safety of HTTPS.

1 bitcoin hash (2 SHA-256 hashes) is approximately equivalent to 3 SHA-1 hashes in terms of number of 32-bit operations, so you are off by a factor 3.

But your point remains valid :)

p1mrx is correct - creating plain SHA-1 collisions shouldn't break the CA system.

Even though it's believed that one can create an identical-prefix collision with that amount of work, after the MD5 Industries demo all CAs now inject at least 64 bits of randomness into the signed certificate. Thus the certificate that they actually sign isn't predictable and doesn't have an identical prefix.

Technically what one needs to break is the target-collision-resistance of SHA-1, and that's standing up much better.

For things like git, however, an identical-prefix SHA-1 collision would be a problem.

Whatever you may think about Bitcoin itself, the _story_ of Bitcoin is impressive. Bitcoin started as a small, open source hacker project by an anonymous fellow on the internet. Somehow, this has snowballed to the point where an entire datacenter's worth of custom computing power is being thrown at it. That's inspiring and amazing no matter how you slice it.

Amidst the on-going onslaught against our digital world, it's refreshing to see what people can accomplish using open source ideals.

It would be nice if all that electricity could be used to help the less fortunate on this planet.

If it means frictionless commerce with anyone worldwide, perhaps it will?

Nothing about bitcoin is tending towards frictionless commerce.

That is an argument people make to excuse the huge waste of power (by extension generating a large amont of pollution) that goes into bitcoin.

The reality is that all the forces that slow down electronic dollars also slow down other electronic currencies.

What forces are those?

The energy required to obtain gold from the earth, when you compare it to bitcoin, makes your comment farcical

Currencies aren't backed by gold. They're backed by governments. The united states dollar is just as much a "virtual currency" as bitcoin.

All currencies are a shared delusion. If everyone believes something has value, it does.

Open your eyes. Bitcoin is helping the unfortunate on this planet:

- it is helping Argentinians escape their government's stupidity who is inflating their currency and limiting access to safer currencies (eg. USD) [1]

- it is helping Iranians working or living abroad to send bitcoins to their families [2]

- it is freeing people from financial censorship, eg. oppressive governments freezing bank accounts or donations to political opposition

- etc

The effect of Bitcoin on society is just barely starting to be seen! A decentralized currency truly has an amazing potential.

[1] http://blogs.wsj.com/moneybeat/2013/07/17/bitcoin-downloads-...

[2] http://www.businessweek.com/articles/2012-11-29/dollar-less-...

You call Argentinians and Iranians unfortunate? Even US citizens are living under financial censorship, are they unfortunate?

mrb means the poor people who don't have enough power to light up their homes at night.

Here ya go:

http://www.pymnts.com/briefing-room/issuers/virtual-currency...

Oh right, all resources should only be spent on literally the most unfortunate single human on the planet, until he or she becomes the second most unfortunate human on the planet, ad infinitum.

If you're interested in a Bitcoin like currency without mining check out Ripple.

If you're interested in a scam, check out Ripple...

I've never heard of ripple before the GP's post, any particular reason why you consider it a scam? After all, many people consider bitcoin to be a scam as well...

The coin is issued by a central entity who has kept 50% of it. This makes people suspicious. Bitcoin has no central issuing entity, thus no one person to 'get rich quick' in some scam type operation.

Instead it has a few early adopters with massive stakes, and a roughly 90% hoarding rate from the last analysis I saw.

Yeah, the early adopters got rich. I think that's fair because they invested in something that was really uncertain at that point. You could even argue that if you buy bitcoins now you're still an early adopter.

Bitcoin itself is less of a pyramid scheme than gold. This is because even when the price stops to rise (or even when it collapses) you can use it to easily transfer value across the world.

I don't think there was really much risk there, and the generation seems to me to have been far too stacked at the front end. Just IMHO of course.

I won't, ever, be buying bitcoins for this and other reasons.

http://ripplescam.org/ has a bunch of arguments for this.

Or PPCoin for that matter:

http://bitcoinmagazine.com/6528/what-proof-of-stake-is-and-w...

Shame downvoters. Proof-of-stake is bitcoin minus the constantly exponential energy increasing requirement for profitable mining operations.

Ripple has the same advantage, but without the benefit that (ongoing) minting of the coin is actually decentralized. In fact you can't see for sure that there is or isn't ongoing minting with Ripple.

All Ripples were pre-minted and in control of the founders. They've only released a very limited supply of them.

That I agree with; it's really the main thing I have against Ripple.

Not a shame: At least so far as has been envisioned proof-of-stake doesn't appear to actually work. The fundamental problem with proof of stake is that there is nothing at stake: Its in your rational best interest to mine all possible subchains that you can mine in, and not only in the single unique chain you believe to be most likely to survive, as is the case for PoW.

PPCoin's security is not provided by proof of stake but by cryptographically signed lockins broadcast to the network by its creator... so you have to trust this anonymous party to behave honestly. It sort of defeats the purpose of having a cryptocurrency.

Ripple is even worse in that regard— an opaque ledger implemented via a closed source system.

Altruism and defaults are powerful things. In fact, they're the only thing enforcing rules about "nonstandard transactions", without which the blockchain would have been DDoSed all the way to a terabyte by now.

And the checkpointing system is a backup measure used to maintain stability because PPCoin is still small; it is not intended to be the primary mechanism holding it up. If you want to see an altcoin without checkpoints, look at any of the ones that got killed by a 51% attack.

I think you are wrong in this.

The source is open, you can build your own chain separate from PPC with the same (or incompatible algorithms), and there is plenty at stake; you might not think your chain will ever be long enough to win, but maybe your transactions need to be private and then there's that at stake.

It is impossible for me to imagine mining all possible subchains that you can mine in; maybe it's because there is no pool I know who supports merged mining in more than just BTC and NameCoin, but I thought there was a technical reason why it wasn't possible (or especially why it was possible specifically for this pair).

You can mine TerraCoin and PPCoin today when you don't need those hashes for BTC, but you can't mine all three at once.

So, how do you propose to mine all possible subchains that you can mine in for the PPC Proof of Stake coin? When the difficulty drops on one chain, it would be to your benefit to mine just that one chain, if you think it will be accepted as the longest chain. Unless you have BTGuild on your side, you don't have much hope of making the longest chain, unless you found a chain that they just forgot.

When I read the CDF graph, I got the impression there is a sweet spot for payouts on chains that behave according to CDF (and because of the nature of "averages" most of us don't have it yet and never will.)

You sound like a person who knows, so I hope you'll tell me more, since I'm interested in Proof-of-Work as it applies to PPCoin. I like the PPCoin website and if that's any indicator, I think that some people will pick PPCoin over Bitcoin without any technical expertise even if it only "seems fairer".

So, will you tell me more of what you know?

There must be a law that describes this type of comment. Something to the effect of "When any given project passes a certain inertia, someone will invariably comment that 'it would be nice/better if XXX could be used to help the less fortunate on this planet'".

We can start applying this law to things like String Theory, cures for Male Pattern Baldness and whatever else doesn't directly benefit some 3rd world shithole.

(P.S. I live in a 3rd world shithole :)

Right, except the bitcoin stuff is essentially make-work to shore up the built in 50% attack/weakness in the bitcoin system.

It would be nice to have a crypto-currency that didn't rely on this constant thrashing.

Not nearly optimal, but this is a start:

http://bitcoinmagazine.com/5635/primecoin-the-cryptocurrency...

You assume that energy that isn't used for the network would automagically go to "less fortunate" people. It wouldn't. Power lines don't appear out of thin air, neither do governments who provide a stable environment for them to be built in.

And how does your browsing HN help the less fortunate? Where is the limit between "good reading" and waste of time?

No, see, this is something that applies only to other people.

Well, you're in luck, because bitcoin has the potential to do that.

So how much of your income are you donating to the poor?

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