Topic: blockchain storage requirements - page 3. (Read 2104 times)

False.

Interesting to find out Moore's Law is applied to storage (I thought only speed). Speed of course has no brick wall, you can halve your distance eternally, but (ignoring quantum computing) if you pack a "transistor" into the space of an atom, you're pretty much done. Actually I take that back. You can only halve the distance between transistors until they are an atom apart. Same thing I guess as storage problem.

But I thought the mining algorithm only kept getting harder due to increasing blockchain size. So if you remove stuff it screws with the system.

It does however the proof of work is in the blockheader.  The block header is only 80 bytes every ~10 minutes or 4.2 MB per year.
https://en.bitcoin.it/wiki/Block_hashing_algorithm

Of course that assumes an average 10 minutes per block, if the network hashrate is growing it will be higher so you could add say 30% to assume average 30% network hashrate growth over time and it still is ~5MB per year or 1GB every two centuries.

The overwhelming majority of the blockchain size is from transactions not blockheaders.  That size will depend on tx volume which is hard to quantify.  Currently their is a 1MB limit per block and the post above shows the max size per year under that limit but eventually that limit will either be removed or raised.

Still even that doesn't tell the "whole story" because the full historical block chain is not needed for either mining or verifying transactions, only the pruned blockchain which contains a copy of all unspent outputs (UXTO) is needed for that.   Currently the UXTO is about 10% of the full blockchain and as a % that will decline overtime.  Estimating the size of the UXTO requiring guesstimating the likely number of future users and the average unspent outputs per user.  The second factor is going to vary wildly depending on what usage scenario of Bitcoin in the future.  If Bitcoin is used primarily as a store of wealth (think digital gold) then the UXTO can be relatively small compared to the user base, and if it is a common high velocity transaction medium then the UXTO may be very large compared to the base.

So making any guestimates for something more than a century away is pretty much a shot in the dark.  The good news is that Moore's law is alive and on any century long timeline Bitcoin simply can not grow faster than Moore's law.  That means that over the course of a lifetime the relative "cost" will go down.  As an example a 6TBs of storage today costs less than a 1GB hard drive I purchased in 1995.  That is a 6,000 increase in storage per dollar in less than 20 years.   I have no doubt that in 20 more years a multi PB drive will cost less than a TB one will today.

Do you know how many nodes there are?

There is supposed to be a block every ten minutes, but they sometimes come along faster when the network is steadily growing. Right now, as already said, a block is generally nowhere near the maximum 1MB limit, but last I checked we were still around 6-8min/block.

So, today, you are looking at adding 36MB of data to the blockchain per day. At the most, you are looking at 144MB/day. There's already over 14GB (please confirm!) of data in the chain, so at some point "archiving" older years of the chain might be necessary.

But bandwidth is still relatively low, and storage space is cheap. Running a node is hardly a cost in the grand scheme of things, and it's not even necessary for normal users.

https://en.bitcoin.it/wiki/Block_chain

I don't understand this. I thought the blockchain had "proof of work" information.

@zatoichi Blockchain is interesting because technically it doesn't store cryptocurrencies but stores transaction information only.

So nobody's done a "cost of ownership" study for this product?

The block size is dependent on the number and size of the transactions included in the block.  So it is impossible to guess how big blocks will be in the future and thus how big the block chain will be.  There is currently a 1MB maximum block size, but who knows if that will remain the maximum as the number of transactions increases.  You could just take the current block size (around 250KB) and use that to guesstimate the future block chain size.

Anybody ever try to calculate the blockchain size when the last coin is mined? And the cost of that storage (assuming a network of a "reliable" size)? What kind of fee would be required to process one transaction at that time? Also if all current transactions globally were recorded in a blockchain, what would be the daily incremental increase in size?