I don't understand the hype with blockchain.... Everything at the end relies on a huge network of miners which uses a whole lot of resources and energy right?

So isn't the cost of running one of these extremely high? And well another source for pollution, climate change? The hardware isn't running on clean energy I think?

I think you're fairly dead on, but i could be wrong

You seems to be confusing Cryptocurrencies with Blockchain.

All cryptocurrencies are blockchain tech, but not all blockchain tech is cryptocurrencies.

Your comments are correct about Cryptocurrencies, but do not apply to blockchain as a technology.

@leanrob the idea is the same though? You need a network of machines continuously entering and double checking all the transactions made on the network. The only difference is you don't get a reward for being the first one to add/verify a new block?

https://blockgeeks.com/guides/...

Seems pretty much like I thought it would be...

And it says "cuts out the middleman" but the problem I see is it replaces it with 1,000s of energy sucking nodes. So which one is more efficient?

Also these nodes will compete for customers and set prices for access. Maybe it'll get cheaper in the short term.

Most likely eventually they will form a group like OPEC and distribute the turf and set prices...

There are 2 major, breaking flaws in OPs comments...

1. The purpose of new technology is not always (or even often) to decrease energy consumption or network los of any kind. Greater technology almost always requires more power so I see no point to a Luddite argument.

2. Of course prices will go up and eventually be controlled. Almost every invention and achievement in human history has eventually become controlled, and then monopolized. To complain about this is like complaining about the sun rising. It is in human nature to corrupt. That doesn’t mean we should stop trying.

In the end. It seems to be a lack of understanding of the powers of a new technology. That article looks interesting and I would suggest reading it and learning further or just ignoring the whole blockchain thing and hoping it goes away.

Hint: it isn’t going away

I wonder when will people realize that the only real 'crypto currency' that's 100% reliable is a solar panel mounted on your house, selling the extra energy you don't manage to use back to the city.

Isn't blockchain just a data structure where last entry is encrypted with hash of the last one like others said before?

But in cryptocurrencies the calculating of hashes is just a way of distributing the chain and making sure that everybody are agreeing on it. The energy hungry nodes are part of the disturbed system, not part of blockchain per se.

The network of a cryptocurrency would keep working even if there was just a single laptop doing all the mining - users would not even notice the difference.

The reason why there are so many miners is profitability: the financial return they expect from their computational power is greater than the energy costs, so it's a financial incentive.
A positive side effect of this (for the cryptocurrency) is greater security against malicious attackers.

So no, cryptocurrencies don't *require* massive power consumption - nor do they use it, really.

@endor but the miners are needed to process and verify the updates to the chain though? The profit is just an incentive to do it?

@RustyCookie then how do you do the processing, no inventive but still need those types of resources?

@endor
I don't really buy your argument about users not noticing any difference if there was just one laptop mining.

The whole reason to have miners from the currency perspective is to verify blockchain so that everybody agree on it. And there's principle which states that chain that has done most computation is the real untampered chain.

Transactions need to be added to the chain, and that is made by miners. Miners calculate hashes (bruteforcing numbers) and who finishes first gets to add new block. Enduser must get their transaction to the block via miners.

Now if you replaced all miners with one laptop it would take a very long time to create new block and users' transactions would be very slow, and not really secure since only one miner controls the chain.

@okkimus re: chain security - yes, as I said earlier, the more miners, the more decentralised is the network, and thus safer from potential attackers.

Re: block time - this is where the difficulty algorithm kicks in, and it's a topic that many fail to grasp at first.
The difficulty of the next block (ie: the average number of hashes that the whole network has to check before finding the next valid one) is regulated in such a way that the block time stays fixed around a set value (10 minutes for Bitcoin, 2 minutes for Monero).

If the network hashrate goes up, so will the difficulty. If it goes down, diff goes down. In general, network_diff = network_hashrate * block_time.

Thus, if the network were to become smaller and smaller untill all that was left was a single raspberry pi, the diff would eventually adapt.

As for checking the validity of the chain: that job is assigned to nodes, not miners (which is why each pool requires a node to submit its blocks to the network).

@RustyCookie OK so I guess Twitter micro payments, removing the middleman to reduce fees. What kind of infrastructure are wet looking at.

Fintech all wants blockchain to replace the slow interbank clearing system. But its not a crypto currency.

Basically I can you give me an example (that's not $$), show me. don't just tell me a hot word/theory.

@endor right do each node holds the full record like a bit repo and they're basically all going to do the same calculation N times.

Current systems I guess is just one master node? So I guess blockchain rely just men's redundancy?

Like a failover setup/P2P network?

@billgates for a cryptocurrency you need miners, because it relies on a public, untrusted blockchain. Thus, miners look for new (valid) blocks to add, and nodes verify their work, and reject anyone who doesn't follow the network rules.
And yes, the profit is there to incentivise the miners to keep doing their work.

An example of private, trusted blockchain would be git commits: in that case you don't need miners, since only the owners of the repo can commit (others can make pull requests, but they are processed by a central authority - aka the repo owners). You also trust the chain, since the commit hashes are more of a reference/data integrity check, rather than a way to ensure your data is truthful

@RustyCookie right I mean like a link. Yea I've heard about blockchain smart contracts on Etherium but that's a cryptocurrency.

@billgates correct, the whole point of decentralisation is to have as many nodes as possible connected in a large p2p network, such that even if one node (or a few) goes down or is compromised, you can still do an integrity check and eliminate the bad nodes.
This also prevents any central authority from manipulating the data against the will of the users

The same argument could be made about gold.