Pieter Wuille is highly respected because he is one of the devs that made the right conservative approach during the 2013 fork. Still, his proposal can not be taken without careful review

We know that every large player here in bitcoin community never listen to anyone else but only themselves, so unless a proposal can be understand by them it will just be ignored. People ignore Gavin's solution just because they don't understand the potential risk for his radical change in block size limit. Similarly, if Pieter's solution is so complex (much more complex than Gavins) that it is not understandable for majority of the large players, it will just be ignored. You can never convince the large mining pools with those slides

"What are the advantages of this? It allows you to drop the signatures from relay whenever you are relaying to a node that is not actually doing full-validation at the time. "

So this solution still does not help full-validation nodes, it only improve the relay speed for SPV nodes. But SPV nodes could just connect to the latest full node to get faster access, they are not the bottleneck for the whole network

I have watched this video twice but still don't really get it

So far as I understand Pieter's proposal, a spending transaction is first validated by the mining nodes by checking its signature, then after it is validated, the node will include the transaction in the next mined block, but without that signature

However, this will create a security question for the other nodes receiving such a block: Without signature, how do they know the transaction is valid? Is it possible for a rougue node to forge a block with lots of invalid transctions but appears to be all validated by that node?

Normally all the adjacent nodes have similar mempool which contains similar transactions. If a transaction is already in their mempool they will know it is valid or not. However, if a new block arrives from far apart which contains many transactions not in their mempool, they need all the data of the transaction, especially the signature to validate it

Otherwise you would be able to spend bitcoin at any address without the signature

I'm not very sure how it works today, e.g. what kind of check other nodes do to make sure it is a valid block with all valid transactions, have to check it back


A side thought: I suppose the original Satoshi client design tried his best to be both secure and efficient. If there is such a large room of efficient increase without impacting security, why it has not been implemented before?

I remember 2-3 years ago there was a talk about the separation of transaction data using two chains to get rid of the forever growing block size pain, then after some deeper discussion it turns out you can not secure the separated part from being tampered, so it seems everything in a transaction is a whole and need to be included and secured by hash power altogether, which is the most efficient way

It is possible that your private key is already stolen before you set the password. For example, some Trojan has been installed before you install the core client, and they constantly searching for the wallet.dat file on your c drive. Once found, they immediately send the wallet to the hacker, and that is before you even set the password

Possibly a password theft if your password is too easy to guess (several words you always use) but in order to steal your coins, the hacker must also have access to your private key. In fact there is no 100% sure way to make sure that no one else have your private key unless it is generated by you manually and kept offline secretly

The entropy in core client should be strong enough to avoid key collision, but the key should be generated offline and kept offline most of the time

It has endless possibility, purchasing other things is just a low level application. I guess by that time, bitcoin is an universally accepted payment method for AI driven services, maybe ticket to Moon/Mars/Time travel were also sold exclusively for bitcoin

And those users will use their bitcoins to purchase things. That liquidation has to be supported by either merchants accepting bitcoin payment or investors on exchanges

The ultimate support needs to come from merchants, and is driven by payment processors like bitpay. At first merchants might cash out their coins immediately on exchanges, but over time they will discover that bitcoin always goes up in value long term wise, so some merchants start to hold bitcoin as reserve, and if in future every merchants have certain amount of reserve, they would directly use bitcoin to settle their transactions

This comment is totally wrong. The current system is obviously totally centralized: FED owns every USD that has ever been created, that is 100% of all the money supply. They just spent them so they don't hold them anymore, because they don't need to hold them, they hold assets instead, when they need they just print some

You can pay with bitcoin mobile payment, but I guess most of the people will not do it unless their coins have rose 10X in value. And even their coins have appreciated a lot, smart people might still like to spend the depreciating fiat money first, unless they don't have any income in the form of fiat money at all

Typically a bitcoiner will spend his coin and recharge same amount of coin immediately after consumption, which makes the whole process of spending bitcoin much more complicated. You better skip that spending altogether and using exchange to cash out the bitcoin in small batches when the price is more favorable

A possible place that you would prefer to spend bitcoin is when you are traveling abroad, in those occasions, spending bitcoin is not any different than spending any other foreign currency, it always involve a currency conversion. If you can directly spend your bitcoin then you don't need to pay the conversion fee, the conversion to local currency will be done by local merchants instead, and they might select to hold bitcoin as reserve

Actually no pools can change the monetary policy of bitcoin, unlike those banks can always reach an agreement of printing more money (500% more during last QE, equal to a 500% tax on everyone using fiat money except banks)

If a pool tries to change the monetary policy of bitcoin, he will just fork into another coin which no one cares about

The most important is its credibility and widely accepted by merchants all over the world. From this point of view, bitcoin's merchant acceptance is already better than gold, which require merchant to have specific tools and expertise to verify its purity

In fact from a higher level of abstraction, all the assets like gold, land, stocks, bonds, goodwill, their value all lies in people's demand for those things. But the biggest demand of human is money, since money can indirectly satisfy any other kind of demand. And bitcoin being a money with limited and shrinking total supply, long term anti-inflation, rising acceptance level, will just attract more and more users

Every machine on the way add a delay,  10 such notebooks will be enough to make some miner not receiving blocks and keep building blocks on a chain which will be invalid later, thus in their blocks, transactions with one confirmation would become invalid after 10 minutes

I just watched Peter Todd's speak from Hong Kong conference, he had an interesting point: It is the hash power decides, e.g. when chinese mining pools have large hash power and slow network, while rest of the world have super fast network but less hash power, then the miners in western will often be working on wrong blocks due to they could not receive correct blocks from china in time and they are slower than chinese miners in finding blocks

In fact, the scale of USD in SDR did not change, it is the other currencies were pressed down, means that IMF is still controlled by US bankers

If satoshi set the limit to 8MB, then during the spamming attack in October many nodes would have already failed. Current mainstream computer hardware and home network simply can not handle 8MB blocks

If you look from the view of miners, a large block size limit will not affect them, since miners will just mine an empty block without including any transactions, then that empty block will be quickly broadcasted to the rest of the network, regardless of how large the block size limit is

On the contrary, if a miner would like to include 16K transactions to form a 8MB block, that large block will greatly slowdown his processing, making him impossible to verify the transactions and broadcast that block in 10 minutes, e.g. his block get orphaned

So from miner's point of view, they always prefer to include as little transaction as possible to maximize their mining income, unless the fee is so high that including those transactions will greatly increase their mining income. But anyway, beyond certain size, no matter how high the fee is, they would not be able to include new transactions, since their block simply can not be relaid to the rest of the network in 10 minutes

The only solution that scales is clearing based design like lightning network or offchain centralized local clearing center, and bitcoin network will work more like Fedwire system, only handle large transactions between thousands of banks (Which means no change is needed since Fedwire system which handles all the transactions between US banks only do 4 transactions per second now)

In fact, clearing and settlement is a very smart design in financial world, it works with all kinds of financial transactions. Being decentralized does not mean fully distributed, there will be thousands of bitcoin hubs that do clearing between them, and bitcoin network is still enough decentralized

You can imagine that similar to bitcoin community, a group of banks could build their own community, start an altcoin and use that coin to send money between them, they could even decide collectively on a 1:1 peg to USD or Euro for that coin to remove the exchange hassle at both ends, so they now can send money to another bank fast through bank's blockchain

But they can already do it today without blockchain: All of them have some kind of currency exchange contract to clear the international settlement daily. So why go for another technology which they are not familiar with?

From criminal's point of view, use bitcoin is much more dangerous than cash: Their wallet might be emptied by hacker, and unless they have a very sophisticated coin mixing scheme, one of their bitcoin spending/selling might reveal all their previous transactions and get them caught

For example, police know that some addresses received illicit funds, then they will mark all the transactions originating from these addresses to be suspicious. No matter how many times the criminal mix his coins, eventually he would like to spend some of his coins at somewhere, either at an exchange or a specific merchant, then police might find a high rate of relation between these addresses and also identify the owner

There should be many patterns for typical money laundering actions, if police do enough amount of research, even the criminal himself might not understand how he get caught. Because of the openness of blockchain, law enforcement are much easier to trace the money than traditional financial system, where they have no right beyond the boarder. And they don't need to blacklist the address, they just quietly follow it and see how it evolves maybe even bigger guys behind it

So from the surface, it seems the address is not related to identity, but the user never know if someone is tracking his transactions, this is the biggest threat for criminals, they don't need to worry about this when they use cash

In fact, the earliest banks in history are evolved from exchanges, so I'm not surprised that one day Bitstamp or BTCC/Okcoin paying you an interest to put your coins there

The problem is, unlike fiat money, banks can loan out them to get some return to pay for depositor's interest, when you loan out bitcoin, it is very likely the coins will never return due to coin appreciation, and banks can not print money to replace those bad loans like fiat money, so there is no way for a bitcoin bank to generate profit

And just like MTGOX, these exchanges do not have the possibility to ask for a bailout from the government in case of a crisis, and they are not covered by FDIC insurance either, so they are totally on their own, the risk to put lots of bitcoin there is much higher than putting some fiat money in the bank

Ok, if you want to print 100 times more money, then price will rise as you anticipated, but if you print a couple of percent or even 500% more money, the money supply and inflation have no direct relationship. Or to say, the margin of error is so large that it is usually 1 magnitude of variance, quite useless in reasoning anything

And notice that all the official indicator of inflation do not include capital goods, like house and stocks. So even house and stocks' price rose by 10 times, there would still be a deflation in daily consumption goods (oil for example) and banks need to keep printing money to drive up the inflation.

In fact they just take the chance to buy more capital goods. Most of the printed money nowadays are used to gamble on various capital goods, do not enter the traditional economy at all, even if they enter in the form of investment, the result is overproduction and the drop in consumption price, e.g. deflation by academic definition

I think the miners who are willing to take lots of transactions and risk the block being orphaned are making some marketing campaign: In order to attract new users, bitcoin must provide some real tangible benefit, low transaction fee is a clearly visible benefit, and when more people are attracted, bitcoin price will rise, then the value of miners' coins will increase by more than 10%, enough to offset the loss from orphaned blocks