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China orders Bitcoin exchanges in capital city to close

bbc.co.uk

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Re: China orders Bitcoin exchanges in capital city to close

#221

Post by occamrazor »

yourapostasy wrote: post #177
occamrazor wrote: post #93

Earlier quoted context omitted.

Forex commissions are lower than 1%. Which exchanges offer better rates on a fiat/bitcoin/fiat transfer?

Where are you getting below 1%, and how much are you exchanging? I'm working with 5-figure USD amounts, drafted on paper checks, and I'm averaging right around 1-1.2% after all costs are accounted for, but not below that.

I had in mind transactions in Europe within the SEPA area, eg EUR/GBP/CHF. Banks charge nothing for the transfer, 0.5% fee, and the spread which often is 0.1% or less. FX brokers have even better conditions for high volume customers.

Re: China orders Bitcoin exchanges in capital city to close

#222

Post by yourapostasy »

tonfa wrote: post #213
yourapostasy wrote: post #210

Earlier quoted context omitted.

How do I get in touch with a "Stock broker with FX"? That's not a term I'm familiar with unfortunately, and searching that string turns up either FX brokers, or FX trading platforms. I've spoken with my US equities/funds brokerage firm, and they have an FX desk, but they're still more expensive than the dedicated FX broker I found and currently work with. Before that, I was regularly raked by my US bank for 4-6% off…

https://www.interactivebrokers.com/en/index.php?f=commission... (Not an endorsement in any way and I'm sure there are others). Fees are min($2, 0.002%), typical spread is a few pip or much less (eg. EURUSD at the moment: 1.20015 (sell) 1.20020 (buy)). But you'll also need a bank account in both currency most likely. edit: maybe a downside, but there's a min $10/month activity fee at IB if you have less than 100k hold…

Thanks, I'll keep them in mind if a wire transfer comes up in the future, that looks useful. Unfortunately, many of my non-US customers still request remitting in their native currency via paper check. And IB doesn't seem to accept paper checks from commercial entities other than banks.

Part of my forex broker's value add is they have banking points of presence in many nations, and can accept the check there, then convert to any currency I designate (typically USD). That would probably explain much of the spread between IB's and my FX broker's margins.

Re: China orders Bitcoin exchanges in capital city to close

#223

Post by freeloop2 »

tboyd47 wrote: post #216
freeloop2 wrote: post #200

Earlier quoted context omitted.

Your link doesn't address the question. It's about an invalid transaction within the block, not the refusal to place a particular transaction into one. With over 50% of mining power you can definitely do this.

https://en.bitcoin.it/wiki/Invalid_block > Clients will ignore invalid blocks when determining which chain is difficultywise-longest. Mining clients will not build on top of invalid blocks. Clients will not propagate invalid blocks (or invalid transactions). Proof of work does not mean full nodes trust miners blindly. It only means they prefer the longest chain that follows the rules . Like I said, yes, with 50% mini…

A double spend isn't an invalid block. This renders the rest of your argument invalid.

Re: China orders Bitcoin exchanges in capital city to close

#224

Post by Dylan16807 »

coryfklein wrote: post #212
XR0CSWV3h3kZWg wrote: post #190

Earlier quoted context omitted.

If you control >50% of the hash power you can also censor tx by ignoring any block that contains them.

Same story if you control 1% of hash power. Anyone can ignore any block, but you can't completely block a transaction unless you prevent it from being included in ANY block. Even if 90% of the hash power is blocking your transactions it just means it takes 10x longer for your transaction to go through.

This is not ignoring transactions, this is ignoring any block that contains those transactions. You make your own pure chain that's longer, and everyone else uses it too because it's longer. If someone else mines a block then such a transaction can temporarily get a confirmation or two, but the 90% steamroller will come by and quickly reduce it back to 0 confirmations on the longest chain.

If someone with 1% hash power ignores certain blocks, they make a chain that's totally irrelevant in their own corner. If someone with 60% hash power does it, they win.

Re: China orders Bitcoin exchanges in capital city to close

#225

Post by Dylan16807 »

tboyd47 wrote: post #217
XR0CSWV3h3kZWg wrote: post #189

Earlier quoted context omitted.

If you control 50 + epsilon percent of the hash power you can censor blocks at will. You can ignore every block that anyone else makes and still have the longest chain.

Except for the fact that they can still get confirmation from the other 50 - epsilon percent. Having 51% of hash power doesn't mean you mine 100% of blocks. That's not how Bitcoin works. With 51% you will probably mine around 51%.

You're forgetting that every miner chooses how they mine. Someone with 51% hash power can decide to always mine on top of their previous block, ignoring what everyone else does. And because the 51% chain is longer, the 49% chain get discarded by any miner following default bitcoin rules. So the effective block rate gets slowed down, and the person with 51% of the power has control of 100% of the canonical blocks.

Re: China orders Bitcoin exchanges in capital city to close

#226

Post by partiallypro »

AlexCoventry wrote: post #151
partiallypro wrote: post #136

Earlier quoted context omitted.

There is no argument, it's a fact. There is capital flight out of China. Their FX reserves have plummeted because they are trying to support the Yuan from dropping off the side of a cliff.

> Their FX reserves have plummeted On what timescale? WP says they have $3T, same as 2016. https://en.wikipedia.org/wiki/Foreign-exchange_reserves_of_C...

Says the very Wikipedia article you just linked?

https://www.reuters.com/article/us-china-economy-forex-reser...

Re: China orders Bitcoin exchanges in capital city to close

#227

Post by tboyd47 »

freeloop2 wrote: post #223
tboyd47 wrote: post #216

Earlier quoted context omitted.

https://en.bitcoin.it/wiki/Invalid_block > Clients will ignore invalid blocks when determining which chain is difficultywise-longest. Mining clients will not build on top of invalid blocks. Clients will not propagate invalid blocks (or invalid transactions). Proof of work does not mean full nodes trust miners blindly. It only means they prefer the longest chain that follows the rules . Like I said, yes, with 50% mini…

A double spend isn't an invalid block. This renders the rest of your argument invalid.

> For each input, if the referenced output has already been spent by a transaction in the main branch, reject.

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

Re: China orders Bitcoin exchanges in capital city to close

#228

Post by tboyd47 »

Dylan16807 wrote: post #225
tboyd47 wrote: post #217

Earlier quoted context omitted.

Except for the fact that they can still get confirmation from the other 50 - epsilon percent. Having 51% of hash power doesn't mean you mine 100% of blocks. That's not how Bitcoin works. With 51% you will probably mine around 51%.

You're forgetting that every miner chooses how they mine. Someone with 51% hash power can decide to always mine on top of their previous block, ignoring what everyone else does. And because the 51% chain is longer, the 49% chain get discarded by any miner following default bitcoin rules. So the effective block rate gets slowed down, and the person with 51% of the power has control of 100% of the canonical blocks.

This would make the 51% miners' chain grow at half the speed as the 49% miners' chain, because the 49% are building on both their blocks and the other miners' blocks, whereas the 51% are only building on their blocks.

This, of course, is assuming that the 51% doesn't create blocks considered invalid on the other chain. This would cause a hard fork and it's exactly what is happening now with Bitcoin Cash, except with a much smaller fraction than 51%.

So no, what you are describing cannot happen with the default rules.

Re: China orders Bitcoin exchanges in capital city to close

#229

Post by korzun »

paulsutter wrote: post #41
korzun wrote: post #11

Earlier quoted context omitted.

> Bitcoin price impact is the best way to gauge the significance of any particular news Not really. Timezones are a thing and I'm pretty sure the majority of those exchanges halted trading.

Volume pretty steady https://data.bitcoinity.org/markets/volume/3d?c=e&t=b

The graph you linked to shows a dramatic drop in volume from 09/13@20K to 09/13@2K.

Re: China orders Bitcoin exchanges in capital city to close

#230

Post by freeloop2 »

tboyd47 wrote: post #227
freeloop2 wrote: post #223

Earlier quoted context omitted.

A double spend isn't an invalid block. This renders the rest of your argument invalid.

> For each input, if the referenced output has already been spent by a transaction in the main branch, reject. https://en.bitcoin.it/wiki/Protocol_rules

That isn't a double spend!
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