Topic: Isn't bitcoin too SLOW to be called "instantaneous"? (Read 3958 times)

Exactly. If you're really sophisticated you can make sure your client implementation connects to multiple network regions via some method. With the hashrate as it is, the network is over-secured at the moment. That's because of the block rewards, but as it tones down so will the mining. The average person, even a motivated one, will not pull off a doublespend with even 5 or 10 seconds of delay between transactions. A well-funded one has no reason to use $50k of equipment for huge preparation to pull off anything less than a big payoff, so you just calculate the risk vs reward and pick a safe zone, say ATM limits of $1000 between confirmations.

This myth is perpetuated by the main places we transact, like the exchanges, which still treat 100BTC and 0.1 BTC as the same thing, but at $120K vs. $120, those are obviously very different real-world security and fraud risks! At the current hashrate, a more reasonable method might be 15 seconds of delay for propagation of 0.1 BTC (reasonable at ATMs where it can use the time it takes to count out the cash internally to mask this delay), and maybe 3 confirmations for 100BTC.

They quickly check the blockchain to ensure it isn't a "normal" double-spend and have your ID, so even if there is a problem (and really, the chance of fraud these days with the quick blockchain check is insignificant unless the ATMs accept 50+ $5,000 bills in a single transaction), they know who to sue.

There are Bitcoin ATMs...how do they work to provide instant cash?

the random confirm times are annoying.
I love when they are every 2 minutes, but the flip side is the worst when a confirms are 30 minutes apart.

In the future we will also build infrastructure on top of the raw Bitcoin system to keep transaction numbers down so that people aren't paying fees in the single or double digit percentages for their bar tabs either. That's not much better than the world is now. Where a Satoshi is the smallest unit, sending less than 1 uBTC would necessarily equal a 1% fee, and increasing as the amount sent decreases. Today a uBTC is already about 0.11 cents (meaning 1/9th of a cent). That is already encroaching on the use case of microtipping and PPV web browsing unless bulk clearing methods are used. If 1BTC hits $1M, sending $9 results in a choice of either no fee, or a 90 cent fee. And at this point fees that small aren't really used for prioritization.

No, at that scale, something will exist on top of it, if nothing other than a PPC where P-o-S gains offset your burnt transaction fees, or. LTC's coin age for prioritization, etc. Or we see mining operations morph into something much leaner.

I didn't read all the post so I'll apologise if this has already been said.

The speed of you transaction is based on the fee you include to process it!

In the future businesses that want a faster transaction will have to bid a higher fee that others using the payment network.

This is how the network will fund itself after the coin reward is no longer a factor.

Either none, or maybe LTC and/or PPC. A little diversification is good and was always inevitable.

PPC has some unique non-stupid features, notably Proof-of-Stake, which is interesting. It is "inflationary" which I would dislike, but the inflation is pegged to attempt only to replace transaction fees, which are actually destroyed in PPC, not relayed to miners. In the end it would appear not to be inflationary. It also has a 10-minute block interval, because the PPC dev actually understands probability theory, I assume.

LTC has value because it uses Scrypt for hashing rather than SHA256, which has gotten some criticism because the NSA was highly involved in creating it, and the NSA makes everyone uneasy these days. The concern is they may have a backdoor or some secret knowledge of that particular function that enables them to take control or do something nefarious. Certainly within the realm of possibility, knowing how they operate. Who knows. (I wish Snowden would issue a statement positively indicating he was unaware of its compromise, or better yet that he is confident it is not.) PPC also uses SHA256, btw.

The 2.5-min interval of LTC isn't so short that it's downright stupid, like Zeta, but it's a bit shorter than necessary. 10 may be a touch long, maybe 5 is good, idk, but again, shorter intervals without some new innovation that makes it matter are useless, because it's time that matters, not confirmations themselves. Everyone just got brainwashed into "6-confirmations" without realizing the number 6 was a derivative calculation starting with probabilities vs. time, where Satoshi and the devs suggested 6 as an acceptable border for where confirmations can be considered "statistically improbable to reverse".

The rest of the alts offer no appreciable benefits, really. Jury's out on Ripple, it has some big backers, but I haven't analyzed it, and there seems to be a lot of money possibly skimmed to devs and people, not staying in-network. Not certain. It's an interesting idea, but until the day it's fully open source, I distrust it, and especially with it presenting itself with a name like "OpenCoin" when it is not (they now go by Ripple Labs, but still own the opencoin.com domain). I'd review this: http://ripplescam.org/ and vet things yourself before looking at Ripple. My gut doesn't trust it.

Conveniently, BTC, LTC, and PPC are the top-capitalized cryptos (if you ignore NMC). So the market knows best, too.

i have seen people talking about lots of orphaned blocks but this is not something I have come across when mining myself.  What alt coin would you recommend?

Following up on my other reply as well: If the "Zetacoin" thread is any indication of real-world averages, mining "Zetacoin" results in at least 99% orphaned blocks, which is to be expected for such an idiotic idea as a 30-second interval (which isn't "seconds" anyway). That's how it works. The more you decrease that interval, the more you take from the Bitcoin, "one CPU one vote" concept, and start bottlenecking it with a huge caveat of, "if your internet connection is stable and fast, and if the majority of the network's connections are stable and fast" which makes it not nearly so useful. Never mind that with ASICs already in existence, they can easily attack or just take over the network at whim, since it's a SHA256 coin. Basically, this is one of the worst alt-coin implementations I've ever seen.

Well technically it should be instantaneous, since you can see the transaction almost the second its sent, but you have to wait for it to confirm. Its kind of like my bank. When someone sends money its almost instant, but it stays in a pending state for a while.

I would agree, still the advantages outweight the disadvantages imo!

Nope. Near-valueless confirmations in seconds. The probability of executing a doublespend with "Zetacoin" is the same per unit time as Bitcoin or Litecoin at a given hashrate. If you were buying a sandwich, Zetacoin would suffice (if it had the hashrate and therefore security of a mature currency). But one confirmation means nothing to me. I'd have given you the sandwich upon seeing the transaction at zero-conf on Bitcoin. One "Zetacoin" confirmation (target=30 seconds) means the same thing to me, probabilistically and from a merchant perspective, as this: 30 seconds pass by after you paid in Bitcoin, without me seeing a duplicate transaction sent to another address. We're 1/20th the way to a Bitcoin block, but from a security perspective, it is the same thing. At a given hashrate, the probability of faking 20 "Zetacoin" blocks is the same as the probability of faking one Bitcoin block.

Though since it has perpetual inflation built in, and is pure P-O-W, "Zetacoin" is more like the economics of PPC without all the other good and/or unique things Sunny put into it.

Sorry, Zetacoin has no technical merits, and many downsides (beyond just having no market share).

That's not true.  As far as the transfer of funds, Bitcoin can do it within 5 seconds anywhere in the world.  It's the settlement part that takes confirmations.  Credit cards often take 30 to 60 days to properly settle a transaction.  It's possible for a meatspace vendor to accept zero comfirmation transactions at face value without much risk, due to the fact that a double spend attack while one is sitting inside a pub is very difficult, and that competing transactions on the network can be detected.  Timing is everything with a double spend attack, if the attacker sends the competing transaction too early, the vendor's client is likely to see it before the purchase has been made.  If the attacker sends it more than 5 seconds after the vendor's client does, it doesn't even matter that the double spend was even attempted, as no one will ever see it.  Also, if a double spend attempt is detected, the vendor could simply tell the customer his bitcoins have been denied in very much the same way that a credit card can be denied. 

While no one would be willing to accept anything less than several confirmations for something like a car, it's not unreasonable for in person purchase values of less than $100 at a time be accepted zero confirmations at face value, if the transaction is valid and no competing transactions (double spend attempts) are detected in the first several seconds.

This is where coinpayments comes in.. use fast alt coin that is stable to do small transactions and bitcoin with safer network to do large transactions.. why do u think alts are going nuts? it makes sense..

In the end an insurer can com along and grant you payments based on collateral which is your insurance premium. You pay and if it doesnt go thru insurance company hunts u down like credit card debt etc

This is why bitcoin should be used for online shopping but supermarket shopping should fall to an alt coin like Zetacoin

zetacoin really is lightning fast... confirmations in seconds

What's done is done and you've already revived the thread. New users are reminded to please check the timestamp of the post they are replying to, to avoid necro'ing old topics. Nevertheless, welcome.

This is a topic that has been discussed endlessly, and will continue to be. Things to remember:

(1) With pure proof-of-work based systems like Bitcoin and Litecoin, it is confirmation TIME that ensures security, not the confirmations themselves. The 2.5 minute-average blocks of Litecoin are nice for providing network granularity, getting us to the initial confirmation faster, and for providing a higher capacity for transactions in the blockchain per unit time, but they come at a downside of increased odds of other things like orphaned blocks and other overhead. Decreasing the block interval further is not a good idea with a pure proof-of-work system.

(2) The thing people struggle with, presumably because it is math, is that, for a given network hashing power, 1 Bitcoin confirmation has the same security as 4 Litecoin confirmations. This can be calculated in the same way that Satoshi discusses it in his Security section (section 11) in the whitepaper. The only difference is the granularity, and increased overhead.

tl;dr - Faster block intervals is not the answer or we would have done it already. It just doesn't work that way with proof-of-work systems. I realize you technically are proposing someone create a faster one, not modify or fork an existing crypto, but I just want to emphasize the level of difficulty and where it exists, which is not in the domain of simply making a clone or a POW system with arbitrarily faster block intervals.

Buying online won't be a problem, buying in a pub or even a small shop might be.
I heard about a bitcoin accepting pub in London that had problems with iPhone users because the default setting was to send coins without a transaction fee, resulting in people waiting hours for their drinks...

Credit cards aren't instantaneous but are treated as such, but the get to the equivilent of 1 confirmation faster than bitcoin does.

If double spend risk is low enough, and it is, zero-confirmation transactions are fine. So..... instant. If you need to send considerable money.... wait it out. Then try sending the equivalent via bank wire, or similar, and see which was faster.

Did you guy actually use Bitcoin only once to purchase something?

Go in an online shop and use it. It is instant. (There is no need to wait for that confirmations)

Next Friday might be a good opportunity to try it out. 

Litecoin is 15 mins.   Bitcoin is an hour.   We need something even lighter... a cryptocurrency with migh lighter-weight block targets in seconds.   I'm not certain chain length is the right way to gain consensus either.   The algorith ceph uses for consensus could probably e modified.   I think it's possible to get much more rapid peer confirmation, and I agree.... the first cryptocurrency that boasts rapid confirm times will be the one to win.