I think so.


But what I don't see is how using hashes is any better than simply increasing the block size. You can make use of the fact that most miners already have the transactions of the new block in their mempool even if you don't use hashes. And as far as I know that is already being done at the moment.

The actual transaction data would still have to reach every node in the network.

The reason we aren't simply using 1GB blocks is that the network needs to synchronize when a new block is found. If the blocks are too large this cannot be done fast enough leading to a higher stale block rate.

Now, if a miner wants to verify that a block is valid, he needs to know the actual transaction data. Otherwise he could not check whether the transactions in the block are valid (i.e. no double spends, valid signatures). Therefore, even if the blocks only contain hashes of transactions, the actual transactions beeing added to the blockchain by that block would need to be synchronized among nodes. So effectively you do not gain anything in terms of efficiency with your approach.

Yeah compared to centralized exchanges, cross chain swaps would not scale very well, assuming you already have the your money at the exchange.

If you don't normally store your money on an exchange and first would have to send your coins to the exchange, exchange it, and then withdraw your new money from the exchange, an atomic cross-chain swap would probably be more convenient. And of course more secure.

If you want to learn about how Bitcoin works that book is really worth reading. I read the draft that is available for free at the linked website.

Also I have the feeling that videos, articles and posts in this forum are shallow in most of the cases with regards to the technology. So I think reading the right book on Bitcoin will help you more to understand it than just watching youtube videos.

WhatsApp is a centralized service. That is why it can handle 900 million users in real time. It does not need a protocol for fault tolerant distributed consensus.

Bitcoin on the other hand does need such a protocol because it is decentralized in every aspect. This has nothing to do with the programming language used to implement this protocol.

This is the only thing that makes slightly sense. With everything else you are mistaken I guess.

Nothing points to nakamoto being American. Also I'm pretty sure that Ulbricht does not have the technical skills needed to invent and develop Bitcoin.

Ulbricht however once said that he is not the original founder of Silk Road but that someone handed it over to him. What might be true (although not very likely) is that nakamoto is the founder of silk road but handed it over to other people later.

It's hard to imagine that this is possible. If it actually is PoW then stronger CPUs would be able to do the work faster than weaker CPUs which would make mining with weak CPUs less profitable.

Also if you have a fixed mining puzzle it is always possible to build circuits that are solely made to solve this particular puzzle (a.k.a ASICs). One possibility to circumvent this might be to use a mining puzzle that is not fixed but changes from time to time, pretty much like the difficulty of crypto currencies is always changing. I don't really know if and how you could implement this in a way that makes sense but it might be possible. This would make ASICs useless because you would need some kind of general computing machine to mine such a coin.

It would also be possible to create a mining puzzle which does not require you to provide computing power but a different resource instead. For example storage. But this would not be PoW of course.

China did not ban Bitcoin.

I think the price will go down in the next days because the Bitcoin euphoria recedes a little bit. But I find it hard to imagine that the price will drop to 2000$ within the next couple of weeks.

Yeah I think you got it right.

This basically just means that it is insecure to use bad randomness to generate your Keys. But that's an obvious thing and does not only apply to Bitcoin but to crypto in general.

Isn't PoS completely insecure due to the nothing at stake problem?

Or is there any solution to this problem?

You can change any aspect of Bitcoin by doing a hard fork. So you could also introduce a scripting language that is more powerful than the current Bitcoin script.

I think you are basically right.

If you are mining selfishly anyway then double spending attempts do not cost you very much.

However, the probability that a selfish miner will get a lead of 5 blocks is rather small even with 25% mining power. If the adversary has a lead of 5, the honest network has a chance of 32% to find 4 blocks in a row, reducing the adversary's lead to just 1. The adversary would now have to publish his chain in order to not lose his block reward. Therefore the double spend would fail because the merchants do not yet have accepted the payment of the adversary because of the confirmations needed.

That's just one example of how a double spend attempt might fail. This further reduces the probability of a successful double spend.

So your idea is basically right but the probability for this to work should be rather small. One would have to carefully calculate that taking every possible outcome of the chain race into account. And then you could estimate how long and adversary with mining power x would have to run his attack until (expected time) he succeeds in double spending.

However, at the moment I don't consider this a threat to Bitcoin. Selfish mining increases your relative reward (how much you get compared to what the honest network gets) but it is not a rational strategy if you want to increase your absolute reward (how much Bitcoin you get for the computing power you provide). Therefore the attack you described would have a certain cost because performing honest mining would be more profitable than selfish mining.

@stdo

Listen to what DannyHamilton said, he's right.


Why is it impossible? All big pools are well connected but one of them might be just slightly better connected then the others.
Moreover selfish mining even increases your relative share of blocks if you have a poor connectivity to the network but a minig power of about 33%.

Alright, I understand. Thanks

Why cannot a miner simply operate multiple nodes which send wrong timestamps to their peers and thus push the average time among all nodes further into the future?

Okay thanks. But if the network time is the average time of connected nodes, couldn't a miner simply give a wrong time in order to push up the average?

As far as I understand it the difficulty will be adjusted according to how long it took to generate a certain amount of blocks. The time the generation of these blocks took will be determined by the timestamps of the blocks.

My question now is: Why don't miners simply use wrong timestamps in order to exaggerate how long it took to generate the certain amount of blocks? So instead of putting the actual time into a block they simply take some date that is still in the future, e.g. one year from now. Then generating our certain amount of blocks did not take 2 weeks but more than one year.

As a consequence the difficulty would have to go down, wouldn't it?

So mache ich das.

Die Bitcoins auf Börsen zu verwahren halte ich nicht für besonders sicher. Ich hab schon 2 mal Coins verloren als Börsen pleite gingen, weil sie (angeblich) gehackt wurden (cryptsy und BTer).

Ich würde schätzen, dass die Börsen heutzutage etwas sicherer sind (z.B. Poloniex), weil sie etwas mehr Zeit hatten zu reifen.


Manche bieten die Möglichkeit direkt € einzuzahlen (geht z.B. glaube bei BTC-e). Wie gut das funktioniert weiß ich aber nicht.


Ich kenne keine. Man kann auf bitcoin.de Bitcoins kaufen, ist aber keine richtige Börse. Aber altcoins bekommt man dort nicht.

I don't know any reason for this pump. To me it seems this came out of nowhere.

I also don't get why people are buying this coin because I don't see which advantages it has over Bitcoin.

So what I don't get is how does the consensus mechanism for ripple work?

With bitcoin this is easy: If I want to state what transactions I consider valid I would simply mine on the according chain.

But how do I state which transactions I consider valid in Ripple?