Topic: Size of BTC blockchain centuries from now... - page 2. (Read 10798 times)

Predictions are boring (and risk-free). How about making it interesting and entering an escrowed BTC bet with me on this? We can also do a combined BTC+LTC/(altcoin-of-your-choice) bet, if you wish.

Would you care to argue for your position, instead of just stating it?

It's not at all obvious to me why no block size limit is "certainly the worst choice of all". Nor is it clear to me "that at some point it will have to become limited".

Agreed.

1MB and "infinity" are the extremes.
There is a middle-ground which is a market-driven block size. This is achieved by a fees-market where there is competition for block-space. This was Satoshi's original vision, which still seems very sensible (not just because Satoshi liked it). The 25 BTC block reward is relatively high compared to fees, so a viable fees market won't occur until blocks are about 20 to 50Mb in size. Which is large but not outrageously so. The 1MB limit makes the fees market  stillborn, and never gives this essential feature of Bitcoin a chance to develop.

Hmm, maybe the optimum block size limit is not 1 MB, but "infinity" is certainly the worst choice of all. It is also clear that at some point it will have to become limited... actually I came to this conclusion myself w/o personal agenda before I saw http://keepbitcoinfree.org, so it appeared quite logical to me. Anyway, one has to be very cautious about the pros and cons of increasing, or keeping, the block size limit, I think.

Remark: "http://bitnodes.io/" is interesting - seems that Finland, Norway, Sweden, Germany and Netherlands have the lead when relating the nb of nodes to the population. Interesting when considering where these countries are positioned in the world financial crisis.

This video is FUD designed to further a personal agenda which is to be the renowned architect of the 3rd-party systems, which 99% of Bitcoin users will be forced to use when they are priced away from the blockchain.  

The essence of the video is that decentralization is at risk. Evidence is showing otherwise:
Bitcoin has a record number of active nodes, 350,000+, and this is increasing even as average block size is increasing.
http://bitnodes.io/


One of the alt-coins will have a flexible block size limit. If Bitcoin users find their transactions no longer work they will quickly use the alt coin which does work. Markets cleave to the best technology. Think Tesla's AC dominating world electrical systems instead of Edison's DC which has a niche role. Bitcoin has one chance for glory and a rigid block size limit will kill that chance.

I think people start realizing that increasing block size limit is not a solution but a new problem (e.g. http://keepbitcoinfree.org).

If block size limit is kept, I see no reason why bitcoin should fail.

The scenario that tx fees increase long-term and online wallet services start getting an increasing share in small "off-blockchain" transactions, makes sense to me as a natural and healthy evolution. Also, confirmation times of 10min are no problem then any more for shopping at retailers around the corner.

Also, all the infrastructure built now for Bitcoin won't be built for Alt-Coins soon - BTC is well ahead here.

The recent days and weeks and months an ever-increasing number of alt-coins has entered flooded the market. This does not reduce BTC value as it seems, but it seems to dilute the value of all other alt-coins. It appears that the market-cap of all altcoins together is one thing, and the market cap of Bitcoins alone is another thing (my impression - cannot prove it though). If this is true, it would show that people start realizing that alt coins are just copies for making their creators rich quickly, without any real long-term vision.

I have not yet seen a convincing Alt-Coins, most are dumb copies and some are conceptually interesting but not very transparent in terms of who is behind them, sometimes there seems to be just a single person (like PPC), which does not really create trust.
There is an initiative for "Netcoin" (MC2) - this appears to really become a community-project rather than a new single-person project, however some technical questions are yet unanswered in its concept - will be interesting to follow...

I honestly dont think Bitcoin is going to last until the end of the decade.

The changes required to it to make it work for anyone that wants to use it for any purpose just screams AltCoin. Bitcoin was the model. Its certainly not going to end up being the solution.

Mark my words, By the end of the year. I'm predicting an AltCoin will unseat BitCoin.

Also good job Michael_S on necro'ing this thread

Clearly, I am ahead of times... or not... considering the date of this post...

Yurock, after coming across this thread again after 2 months, I think I agree with all your points.

I think that's the way the bitcoin network is going to evolve.

So I would also say that lifting the 1 Mbyte limit is not really needed, because sooner or later anyway the "small" bitcoin traffic (and also retailer payments where we do not want to wait till the next confirmation at the checkpoint) will move to online wallet services. See also my future vision here.

I believe your guess is reasonable until point 10.  After that, you're failing to understand the situation isn't stable at all, given all the competing interests, hence your 14th point in particular cannot happen.  The situation will resolve itself in the interests of the majority by the limit being increased.  The miners do not have the final say.

You're thinking along the right lines. My prediction:

No. We will not hit today's limit today. As for the near future, I already stated:
Yes. And also a way to add fees to existing transactions. AFAIK, it is already discussed by Bitcoin software developers, so we may see it implemented some time soon. Recipients of bitcoins will also be able to add to the fee.

I would use the word "compete". Competition is an important market force, and Bitcoin is designed to be governed by market forces.

Yes. Transactions cost something to the whole network. Every new transaction has to be propagated through the network and processed and stored (at least for some time) by every full node. Today, a large part of this cost is paid by newly generated coins, I think (but may be wrong). Let those who makes transactions (and thus supposedly needs them) pay most of this cost. Seems fair to me.

Bitcoin is clearly not going to be generally suitable for payments of few cents. Other than that, I think, fees will not be prohibiting. From charts on blockchain.info, I estimate the average today's fee to be below equivalent of 4 U.S. cents. Multiply it by 5, and it will still seem quite acceptable to me.

Remember, here you are talking only about micro-payments. Most people who need to transfer an amount like 10 BTC and up will not care to pay 0.01 BTC transaction fee. And fees are roughly per transaction, not per amount transferred. So, in the future, most micro-transactions are expected to be handled by other systems based on Bitcoin as a unit of value. As for larger transactions, Bitcoin is quite capable to handle them. So, only small (I think) part is going to move to systems that handle bitcoins indirectly. And it does not mean centralization. Cryptocurrencies of different kinds are being developed and launched, like Ripple and Open Transactions. They have no problem using Bitcoin as a unit of value. They may be more suitable for instant payments and micro-payments.

Like Bitcoin to fiat exchanges, they may be points of failure. But the possible influence is limited by at least two factors:

• Only a part of the whole Bitcoin economy will see an influence. Larger amounts of bitcoins that reside in normal Bitcoin wallets will not be affected.
• There will be no monopoly. If, for example, you close one large Bitcoin payment processor, others will catch up.

Your proposal has weak points, but the general idea is worthy, I think. The idea that since total Bitcoin supply is finite, amount of storage required to track every unit may also be finite and within capabilities of future systems.

There are surely things to worry about, and different solutions to the problems have to be considered.

In 1985 the Cray-2 supercomputer was released, and was the fastest computer in the world for five years. It cost about $16 million in 1985 dollars. The memory was 256M 64k words, more than all previously produced Cray-1s combined - 2GB.  It had 1.9GFLOPS of processing power in it's fastest configuration - approximately equal to an iPad 2, and significantly less than the computer I'm typing on.

I think that technology might keep up with Bitcoin.

I think this is very close to what will happen if the 1 MB limit is not increased before the demand for transactions catches up to the limit.

With regards to blockchain size, you might want to take a look at this: https://bitcointalk.org/index.php?topic=88208.0;all

So does this means that due to today's 1 MB limit per 10 min (i.e. per block), if the number of transactions get so large that more than 1 MB of transaction data is generated every 10 min, then some transactions will never ever make it into the blockchain, if their transaction fees are too low?
Then this means that the queue of transactions that are waiting to get into the blockchain will grow larger and larger all the time, because the rate at which new transactions are created (> 1 MB/10 min) would be higher than the rate at which transactions could be processed (== at maximum 1 MB/10min).

If this is correct, then there would be the following consequences for the future of the bitcoin system, as transaction volume increases:
(1) Only transactions with sufficiently high transaction fees will make it into the blockchain at all.
(2) The Bitcoin clients should get a feature to revert transactions that are not yet in the blockchain, because if I transfer 1 BTC to address xxx with a low fee yyy, and after some days or weeks my transaction still does not show up in the blockchain, then I might want to revert my transaction and try again with a higher fee zzz > yyy.
(3) As a result of this mechanism, there will be a real "fight" to get one's transaction into the blockchain, so in practice this means that transactions will no longer cost "almost nothing", but to the contrary, transaction fees would soon become so high that for example micro-payments and small donations become prohibitive due to the high fees, and it would soon be cheaper again to use PayPal!
(4) As a result of (3), people will move to make bitcoin payments more and more inside "closed sub-systems", i.e. bitcoin banks that do their own bookkeeping on their customers' accounts without loading the blockchain. For example there could be a MtGox subsystem or a blockchain.info subsystem, to name just two. When I transfer BTCs from my MtGox account to another person's MtGox account, I would not use the blockchain, but the MtGox internal bookkeeping would carry out the transaction, just like in today's banking system. This would avoid transaction fees, so people will favor this variant. But this also means that many benefits of bitcoin as we know it today would vanish, and the whole bitcoin system would move towards a de-facto centralized system that is again built on trust into a cartel of a few "subsystems" (bitcoin banks), and these sub-systems may even run fractional reserve banking without their customers knowing about this.
So we would again end up with two kinds of money like in today's fiat money system: First the true bitcoin money (corresponding to today's fiat central bank money), and secondly the account balances of the "subsystems (=bitcoin banks)", that may finally run fractional reserve, like today's bank accounts.


Also, these sub-systems (bitcoin banks) would be vulnerable to government interference etc. So with such an evolution we will reach the point when the bitcoin experiment has finally missed its original goals and has failed. I think such an evolution should be avoided!

If my understanding is essentially correct, then I think the only solution to keep the bitcoin system open and avoid the outlined evolution towards closed sub-systems (="de-facto-bitcoin-banks") would really be to change the way that transactions are stored, as outlined in my last post, such that memory needs for saving the blockchain (be it the complete history or only the current state plus a short incremental history) does not increase infinitely.

Maybe my thoughts are relating to what may happen rather far in the future, but this future might also turn out to be nearer than what we think.

...Or am I missing some fundamental point here and all my worries are pointless?

Block size limit is artificial and will be adjusted as needed in the future. However, raising limits opens the network to flood. Increased future transaction fees are supposed keep transaction volume within manageable range. Currently this is my only hope.

Didn't you see the date on this thread?

Oh my GOD are you kidding me? There's a hard coded limit on the number of transactions? We must fix this immediately *snicker*

    

By principle I don't understand how this limit can be possibly kept under any circumstances of btc traffic growth. If one block is generated only every 10 min and shall contain *all* the transactions that have occurred during a 10 min period, and if the number of transactions per minute increases dramatically in the future, then the block size has a lower limit that is determined by this number of transactions per 10 minutes, because the blockchain contains all the information of all transactions, which requires non-zero memory space.

Example: Let's assume that in e.g. 20 years from now there are 1 billion btc transactions being carried out every 10 minutes, which is not necessarily completly unrealistic, assuming >20 billion people on earth by that time, plus companies and computers carrying out automized transactions for certain financial purposes all day long.
Let's further assume that one transaction that is recorded in the blockchain occupies at least a few bytes of storage to contain all the transaction information. In lack of detailed knowledge of the bitcoin protocol, I am making the conservative assumption here that 50 bytes of storage are required per transaction (containing input address(es), output address(es), amount(s) etc.).

With these assumptions, the blockchain would grow by 50 GB every 10 minutes, or 7.2 TB per day, or 2630 TB per year.

2630 TB per year looks a lot, but it is certainly something well feasible by certain nodes already nowadays.

However, this number is still conservative! Theroretically, this number can be much higher, in fact infinite, whereas the storage capability of any technology cannot be infinite on a finite planet, given the fact that the number of atoms on earth are finite (ca. 10^50) and assuming that we will never be able to store more bits of information on earth than the number of atoms on earth. Hence, if the transaction volumne really gets too high, one has by principle think of another "format" to safe the bitcoin network state: Instead of storing the limit-less transaction history, one may instead have to store the btc adress associated to each satoshi, which leads to a finite rather than infinite worst-case memory requirement:
In the worst case, every satoshi resides on a different btc address. There are 21e6 x 1e8 = 2.1e15 = 2.1 million billion satoshis in existence. If one bitcoin address has 20 bytes of size (again this is a guess in lack of better knowledge, but should be not too wrong), then such a data base that captures the complete state of the whole bitcoin network at a given point in time would be 2.1e15 x 20 bytes in size, i.e. = 42e15 bytes = 42000 TBytes.

My conclusion: With a storage of ca. 42000 TB one could store the complete bitcoin network state (not transaction history) any time in the future! This storage is well within the reach of technological feasability, even today (you could buy this storage today for less than 4 million USD). Hence, there is no theoretical physical limit that prevents future expansion of the bitcoin system. In the worst case however one may have to transition the system in some far future from a "full transaction history" record to a "current network state" format, or a mixed form like "current network state at time t_0 plus differential trade history after t_0", where different nodes may use different times t_0 depending on their individual storage capabilities.

The entire network does not upgrade at the exact same moment.

There will be many not-yet-upgraded nodes that will serve blockchain data to those upgrading to a new database index.


3GB chain data
1GB index

is what I have here.

blk.dat (blk0002.dat, blk0001.dat, etc. in the future) is the actual block chain data. blkindex.dat is the index file.