Topic: how much time is bitcoin transaction? (Read 5071 times)

If you're just mining and trading with a friend, police and other institutions have little reason to get your ip adress

If i have bitcoins only from mining and if i'm making transactions with only a friend, so only he knows who am i, police and other institutions, cant get my ip adress.

Anyway , these cards won't be ever secure, so who cares,  all need 100% secure system like bitcoin has been made for.

what are you talking about, they are totally anonymous, until you don't publish your bitcoin account, no one can check who you paid and who paid you. So its easy than normal to laundering money there .
Examply you have your all money in bitcoins, and when you will have debts in your country, they can't take this money from you, like you would have bank account in Switzerland .

Nobody destroys anything. They are just like real money bills. Please read before posting. Also,

Bitcoins are anonymous

I have no idea where did that myth come from... Anyway, do you feel insecure about accepting unconfirmed transactions? We can always use the central mechanism with MtGox vouchers (I suppose you read my first post in this thread...).

Bitbills... very bad and unpractical idea. You don't have clear value of bitcoin, you have to pay also his owner who produce those plastic cards with this sticker. This is so waste, you pay and card is destroyed, a seller can't give you rest of the money.

Actually this system is so hard to be implemented in real life to pay for products. I think it will be just good alternative for anonymous payments, it won't ever replace standard payment methods.

Well, people can also print fake money... He's talking about Bitbills: http://bitbills.com/

Honestly, if I had a coffee shop, I would accept the payment before the confirmation. It's instantaneous and it takes a fair amount of work to fake that....

well some of the ones i've seen have the private key of the wallet as a qr code and theres a sticker seal so you know its legit.
now if the bitcoin client offered an easier way of importing those keys then the less technically inclined coffee shop owners can accept bitcoins

Also if you use an online bitcoin wallet you can easily resolve that problem

or buy one of those physical bitcoin coins or cards and hand it over

There are three levels of transaction acceptance:

- 0/unconfirmed - the transaction has spread through the network to the destination. This happens almost instantly.
- 1/unconfirmed - a block passed while the transaction was unconfirmed. Reversing a transaction at this stage is extremely difficult. This takes 10 minutes.
- X confirmations - a miner put the transaction into a signed block, and the transaction is official and irreversible. This takes 10 minutes to over an hour, although if a transaction fee is used the transaction will almost certainly be included in the first block.

With the first and the second, a double spending attack can be pulled off but is difficult as eventually (which can be in as little as a few seconds) the node will discover both transactions, while with the third a double spend is impossible without extreme unforeseen circumstances like a bug in Bitcoin itself or someone maliciously exploiting a computing cluster with over 50% of the Bitcoin network's power. Clearly, waiting for even 10 minutes is unacceptable in a grocery store, so the third level of acceptance is impractical. There are two solutions to this problem:

1) Accept 0/unconfirmed and rely on trust. It is not too difficult to run out of a restaurant paying nothing or paying only part of the bill - the latter option allows you to claim that you simply made a mistake if you ever get caught, and it can be trivial to walk into a convenience store, steal something quickly off the shelf and walk out, but this does not happen that often, and in first world countries people have decided that the effort of securing oneself against these types of attacks is not statistically worth it. Such attacks do need to be protected against on the internet, and security is an important issue, but the risks of trying to double spend Bitcoin in physical space are considerable, and there is no "sorry, that was an accident" escape - an attempted double spend attack requires deliberate effort to pull off and cannot be disguised as anything else. Even if the fraud is noticed too late, with security cameras the perpetrator faces the same risk of being caught as he would if he had just stolen the goods.

2) Add a centralized layer to Bitcoin. This is the solution that MtGox released recently. Under this solution, users can create voucher codes that are redeemable with MtGox for bitcoin, so a user can send a code to the merchant who can then use the code to check that MtGox has the bitcoins. Centralization is a weakness of this system, and MtGox and its main potential competitor in such a service, MyBitcoin are both known for less than perfect security, so while this is the most efficient solution it is important to tread carefully here - in the long term there is a risk that such services will be integrated into society and will be required by all merchants, so we would end up with a new Paypal, Mastercard and the like but simply backed by a different currency. The relative ease of setting up a centralized bitcoin proxy would allow for far more competition, so the situation would not be as dire as it is now, but the possibility is there especially if such services become regulated.