Bitcoin Network Security/Integrity How secure are they REALLY?

[triforcelink]

I have been reading around and I must say, I am pretty excited about bitcoins. However, I'm not seeing much talk about the integrity of the coin itself, I understand that there are some risks from the end user perspective such as getting your wallet stolen, but what about the network? There may be a lot of 'advanced' cryptography going on, but doesn't that really mean it will be just a matter of time until someone finds a hole? I'm curious to hear from some the developers as to how confident they feel about this system. (Of course all are welcome to input their opinions)

[Vandroiy]

I think the system is secure with >80% chance. It will need to adapt in the future, but I was not able to find any major obstacle, and I spent some time looking at the dynamics and talking to people who are into crypto.

If you don't believe in cryptography, how can you ever type a password or personal message on the net, let alone do online banking or whatnot? All of this would be broken, most of it actually will be when a quantum computer is built.

But Bitcoin? It will just change crypto scheme while the quantum computer is under construction. The only problem would be if someone acquires a lot of private keys before Bitcoin has time to change scheme. This is not unthinkable, but unlikely.

[Quantumplation]

I have been reading around and I must say, I am pretty excited about bitcoins. However, I'm not seeing much talk about the integrity of the coin itself, I understand that there are some risks from the end user perspective such as getting your wallet stolen, but what about the network? There may be a lot of 'advanced' cryptography going on, but doesn't that really mean it will be just a matter of time until someone finds a hole? I'm curious to hear from some the developers as to how confident they feel about this system. (Of course all are welcome to input their opinions)

Dear god, posts like this are getting created faster than blocks on the network. >_>

The bitcoin network is built on battle-proven technologies such as DHT and SHA256.  Tor, Gnutella, and hundreds of banking, gaming, encrypting, transfer protocols, security measures, SSL, etc all use the same principles that bitcoin bases its security off of.  I doubt bitcoin is going to provide much more motivation than the banking credentials of the entire world for someone to find a flaw, so this isn't bitcoin related.  If someone could have done it by now, they would have.  If a new attack vector becomes discovered, bitcoin is the least of our worries.  So yes, it's fairly secure.

Also, usually I'm not a stickler for this, but really, there's a post on the FIRST page about this.  http://forum.bitcoin.org/index.php?topic=10661.0

I think the system is secure with >80% chance.

Now, why are you throwing random, arbitrary percentages around?  I'd like to see how you arrived at that number (unless you admit that it WAS arbitrary and gut-instinct, then I'll let it slide. )

[Vandroiy]

I think the system is secure with >80% chance.

Now, why are you throwing random, arbitrary percentages around?  I'd like to see how you arrived at that number (unless you admit that it WAS arbitrary and gut-instinct, then I'll let it slide. )

If someone asks me how secure I believe a system is, what reasonable answer can I give, other than an infimum on success probability?

Of course, I have to use a conservative number; if they don't hold on average, my predictions would be worthless. I think 80% is a number I could bet on, under reasonable circumstances (network size, BTC gaining acceptance, exchangeable crypto schemes). A more precise estimate should really be above 80%.

So, uhm, simply said, it's pretty arbitrary. But I rely on it being true, so I strongly believe in it.

[Quantumplation]

I think the system is secure with >80% chance.

Now, why are you throwing random, arbitrary percentages around?  I'd like to see how you arrived at that number (unless you admit that it WAS arbitrary and gut-instinct, then I'll let it slide. )

If someone asks me how secure I believe a system is, what other than an estimated infimum on success probability is a reasonable answer?

Of course, I have to use a conservative number; if they don't hold on average, my predictions would be worthless. I think 80% is a number I could bet on, under reasonable circumstances (network size, BTC gaining acceptance, exchangeable crypto schemes).

So, it was gut-instinct?  Carry on then.  I thought you were trying to say that SHA256 had an 80% chance of remaining secure, and there's simply no data to support that.

[Vandroiy]

So, it was gut-instinct?  Carry on then.  I thought you were trying to say that SHA256 had an 80% chance of remaining secure, and there's simply no data to support that.

Naah, I'm talking about a wild guess on all the technical risks concerning Bitcoin. Including network takeovers if we have too few miners after minting and all those other technical attack scenarios.

SHA256 breaking down... if that is our main concern, we're pretty safe.

Edit: yes, I know, no proof. SUDDENLY, P = NP. I doubt it.

[triforcelink]

If you don't believe in cryptography, how can you ever type a password or personal message on the net, let alone do online banking or whatnot? All of this would be broken, most of it actually will be when a quantum computer is built.

Do you think it would be possible for the entire system to be compromised? Would it be possible, through cracking the algorithm to 'steal' all the coins/value that is being stored on the network?

[Bit_Happy]

If you don't believe in cryptography, how can you ever type a password or personal message on the net, let alone do online banking or whatnot? All of this would be broken, most of it actually will be when a quantum computer is built.

Do you think it would be possible for the entire system to be compromised? Would it be possible, through cracking the algorithm to 'steal' all the coins/value that is being stored on the network?

Not possible:
1) The odds of 'cracking' one single private key to steal coins at one single address are nearly impossible.
2) There is no centralized algorithm to crack, so the answer is "No".

[Quantumplation]

Not possible:
1) The odds of 'cracking' one single private key to steal coins at one single address are nearly impossible.
2) There is no centralized algorithm to crack, so the answer is "No".

Attacking the algorithm used to generate public keys in order to find the private keys would be what he's talking about.  If you found an efficient way to "crack" these, you could steal arbitrary numbers of bitcoins.  The possibility of this happening, however, is slim to none.

[Dude65535]

If someone found a way to easily crack the private keys any bitcoins they stole would become worthless as soon a people figured out what was happening.

However it would not necessarily be the end of bitcoin. As long as there was still a secure public/private key system to switch to bitcoin could use that. Then we revert to a point in the block chain believed to be before any thefts took place. That would be non trivial and very painful but it could be done.

[unk]

I have been reading around and I must say, I am pretty excited about bitcoins. However, I'm not seeing much talk about the integrity of the coin itself, I understand that there are some risks from the end user perspective such as getting your wallet stolen, but what about the network? There may be a lot of 'advanced' cryptography going on, but doesn't that really mean it will be just a matter of time until someone finds a hole? I'm curious to hear from some the developers as to how confident they feel about this system. (Of course all are welcome to input their opinions)

the short answer at a high level of abstraction, considering the cryptological and economic system as a whole, is 'your value is more secure than you might have guessed intuitively, but less than most hardcore promoters of the technology claim'. (i consider myself a strong promoter of the technology but a skeptic of the all too common, pyramid-scheme-style promotion of the current block chain.)

[triforcelink]

I would like to close the thread with this: https://en.bitcoin.it/wiki/Weaknesses Thanks everyone for your responses.