ok you've got my intention there, this suggest that you have most of the issues figured out, how do you think we will solve:
You know very well that many of these issues are generalized problems for digital services and not exclusive to bitcoin.
If the answers were trivial they'd be solved already but nevertheless I will give you my opinion on what I personally think about them.
The Block size limit when the number of transaction/minute is 100 times higher than today.
Amusing that you say bitcoin will fail yet assume the transaction volume goes up 100 times.... anyways
The block size limit is more or less arbitrarily fixed and very very trivial to increase in the protocol.
Now you will say "oh, but I argued it will have to change in 20 years..." to which I can reply:
If internet bandwidth and hard disk capacity do not magically stop to grow at all even 100 times more transactions should be manageable.
The block size limit is directly linked to blockchain size and that’s why it is there (it provides more or less an upper bound on the size increase of the blockchain for a given time)
2-The block chain size when it exceeds 200GB or 1TB ? most users or services will have to use clusters of storage, if the adoption rate picks up this has to be fixed really fast.
upon massive growth of bitcoin this can start to become an issue. You have to discern between full nodes and those that only have parts or none of the chain.
The interesting question is how to go about distributing the blockchain. We can implement an altcoin that uses a proof of work function on the data of the blockchain to encourage its decentralized storage.
It is not necessary for each and every node to actually store the entire chain as long as we can guarantee that it, as a whole, is well enough distributed to be secure.
There is a lot of potential data culling you could do and still verify transactions. Ultimately it will be up to the individual to decide if it wants the entire chain or not.
Either way at current hard disk price points it is still quite some time before it becomes unaffordable for the individual to store the entire blockchain.
running a bitcoin node consume so much resources (bandwidth consumption and memory, mempool containing unspent Txid) how do you think a normal user will have to deal with these issues, he will have to use centralized wallets and services which against the fundamentals that Bitcoin was created for in the first place.
The "normal" user won't want to run a full node. As long as
enough individuals do so this is okay. There is still some room upwards before it becomes infeasible for regular people to no longer be able to run a full node without having to spend excessive amounts of money on it. Again it would be nice to see some incentives for actually running a full node without being a miner. Maybe a PoS/PoW hybrid solution as a side chain? (Personally I trust more in the hybrid approach as PoW introduces randomization into the system). I could see how an alt aimed at securing the network might somehow create a mutually profitable situation where bitcoin users more readily embrace the altcoin.
3-The energy waste, it has been known that when the price goes up mining becomes more profitable and more resources are brought online...resources that most of us consider wasted, as of today the hashrate is more that 250 Petahash/s, assuming that the worst chip on the network consume 0.5w/ghs (which is way too optimistic) this means that at this point miners consume way more than 125 hourly Megawatts... just FYI a typical nuclear plant produce from 500-2000 hourly Megawatts.
I don't like the argumentations you sometimes read on PoW requiring energy while PoS doesn't (which is not really true imho).
Nevertheless there is one point you can't deny. To launch a >50% attack you need at least 62.5 hourly Megawatts over quite some time.
This energy is not wasted, it is securing the network. Look at some other forms of energy being wasted. Every bomb launched not only harms or potentially harms lives, it also wastes incredible amounts of resources.
It may sound cheesy but go fight against war before you fight against the energy consumption of bitcoin.
4-DDOS attacks: when Bitcoin become bigger, there will be Big services that run the Bitcoind in order to offer their services, organized groups can run denial of service attacks against these services, you can read more about how they can do it in that wiki I provided before.
DDOS is an issue you face in the internet in general. You can try to optimize with filters and also trusted relaying, though generally that opens other cans of worms as you are now moving towards centralization.
Maybe something like a distributed decentralized whitelist for transaction requests? (btw this is something that worries me about Mike Hearn. He has done a lot for bitcoin but his proposition of flagging coins
basically introduces the same problem. If you apply a filter to bitcoin that filter also needs to conform to the consensus properties of bitcoin, namely being decentralized and to some degree anonymous)
5-Malleability issue, and don't tell me it is not an issue, because it really is, and it is not fixed yet, they just found some work around it.
No, it is not an issue unless you are mark karpeles or code like him
6-Double Spending, even if you don't have 51% of the network you can perform double spending with as little as 25% of the network,
and this did happen before In the type of consensus bitcoin uses it is impossible to guarantee no double spending. It becomes less probable with every new block that a tx is double spent.
The solution: wait for more blocks.
Ok, here is a more productive answer: Multi-signature addresses where the second signature instils some more trust on transactions by not signing double spends.
How it would work: You request a new multisig address from FastTrustPay® network with your public part of the address. They respond with a multisig address as well as an n-lock transaction for the amount of coins you want them to provide fastpay services for to an address you specified. The n-lock tx guarantees to you that you will get the coins back if something goes wrong. It is well advanced in the future but not too far so you will have to wait years for your coins to come back to you again (this is to prevent you from double spending using the n-lock security). You then transfer the exact amount to the multisig address. Every time you want to send a transaction you send a request for n amounts to x.
Fastpay responds with a new n-lock transaction for the remaining coins, and the half-signed transaction with n to x. you add your sig and post it to the network.
Basically the service checks your available funds and only allows you to spend what you have once. If the receiver also trusts the service it will accept your transaction with fewer confirmations as it knows FastTrustPay will not issue double spends
7- The 51% attack, we all know what it is, it is achievable, any government can achieve it if they want to kill Bitcoin, even at this point.
"What if the government takes over BoA or Citigroup?" That argument can be applied to anything. The bottom line is that you can't avoid it in any system.
Consensus can only be reached if you actually have a majority (or eventually have a majority)
If that majority happens to be the other party well bad luck. formally in such a system it is impossible to circumvent.
8-man in the middle or packet sniffing, also described in that wiki.
The same problem applies to all netbanking at the moment. this is an issue of network security and not bitcoin per se.
These are just quick responses. You very well know that there are potential approaches to deal with these issues.
If you stick to your rigid thinking and argumentation it will get you nowhere.
Like p2p filesharing this is a genie you can't send back into the bottle
Adam, did you SODL yet or...?
