Bitcoin Forum

If you wanted to break bitcoin couldn't you just setup a powerful computer to just transact millions of BTC micro transactions back and forth to make the blockchain super huge.

Somebody said its already upto 15GB

What is someone sabotaged it like this and the blockchain became several terabytes of a few petabtyes.

Would that bring all wallets to a grinding halt?

There are several reasons this cannot happen. Primary among them is that the current max block size is 1 MB. Since there is 1 block every 10 minutes on average, that caps the increase in blockchain size.

when too many people mine, we grind to a halt.  this is why we invented quantum mechanics.

What wheatstone said is entirely correct. Meanwhile Carl Quesadilla appears to be some sort of pot-addled clinically insane noob.

In addition, micro-transactions cost fees. Miners would be only too happy to take fees from some very rich spamming malefactor. Said malefactor would run out of money before long.

It costs money to send transactions so they would have to spend a lot of money to do this. Also confirmations are slow so its going to take a while. Maybe somebody will try it someday. Should be fun to watch a) the predictable flash crash b) equally predictable recovery b) attempt at destroying bitcoin fail.

i dont really think its a problem... I think it must be possible
to become a miner even without the whole blockchain -- you
just start at any given point and confirm new blocks.
Probably no one built a client like that yet, but could be coming.
Then again, 16 gigs isnt even that big, so no need for it.

If the bitcoin community decided to send transactions at the maximum rate and all miners were to produce 1MB blocks, at 1 block every 10 minutes 50.6GB (51840MB) will be added to the blockchain per year. It will take 20.2 years to add 1 terabyte to the blockchain.

A 3TB drive commercially available today will be able to store the blockchain of a bitcoin on steroid for more than 60 years.

"640K 1T ought to be enough for anyone".  ::)

What happens when bitcoin volume grows 10fold.  Wouldn't some transactions not get into blocks, slowing down the transaction speed. What's the solution to that

That's not impossible to break the blockchain, pizza_lord.

The are many clients that you don't have to download the blockchain, if downloading and storing blockchain is uncomfortable to you.

This can't really be done. As a miner you need to include valid transactions in a block. But each input to a valid transaction must be an output from a previous transaction, and that can be as far back in the blockchain as you like, basically anything from block 1 onwards. So you need all the blocks.

Having said that, it is possible to have a 'pruned blockchain' structure, which only contains records of unspent transaction outputs. I heard in some other thread that while the 'raw' blockchain is currently ~15gigs, the pruned record would only be 5 or 6 gigs.

Your other point is very important, and it seems the devs keep brushing it under the carpet. We're currently only having transactions at about 1/10 of the total capacity (of 7 tps, imposed by the 1MB block limit and ~10min block gen time). But the kind of mass adoption we're all hoping for would push up against that limit, it might be only a couple of years away. But there are also arguments for keeping the limit in place. Apparently there can be some sort of infrastructure set up for 'off-chain transactions' but I've no idea how those are supposed to work.

So no solutions have been proposed to this problem?

What about creating multiple "parallel" block chains somehow

What problem?

Blockchain growth is capped by max block size, but blocks aren't getting anywhere near that on average, so the real growth is much slower.

Yes no solutions, because nobody sees it as a problem now.

This maybe a problem decades later, if Bitcoin will be extremely popular. But I believe it won't be difficult to solve it with technology level at the time.

The block data is over 17.5 GB as of today, and it will keep growing.

If you have very limited space or don't want to save all that data, you can always use thin client.
But, I think most of the people have way more free space in their computers.

Also, don't forget we are going to have HDD with bigger and bigger size.  :)

While the size of the blockchain is an issue, this threat has largely been mitigated for bitcoin.  However, almost all altcoins especially when first released are usually vulnerable to this type of attack.  I recall doge had this issue for awhile until they increased the fee.

Question: what happens when a block is larger than 1 MB? Do the surplus transactions get moved to the next block?

It is not possible for the miner, to include transaction exceeding the 1 MB limit, that is a hardcap written in the source. Currently only the "best" transactions would be included. "Best" meaning, that they either have many bitcoindays-destroyed, payed a high Fee, or waited for a longer period of time.

million versions of the blockchain is stored in millions of wallets all around the world, if one fails the blockchain refers to the other majority. In other words: blockchain/ bitcoin can't be 'broken'

What you will see in the future is fewer and fewer people keeping the blockchain on their devices. The blockchain will be stored and protected mostly by pools, exchanges, and corporate entities like blockchain.info.