
Bitcoin, blockchains, and national security - drewvolpe
https://blog.sia.tech/bitcoin-blockchains-and-national-security-d2f8c65c671b
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Animats
If the Great Firewall of China started blocking Bitcoin transactions, which
could happen at any time, most of the mining power would go offline and
transactions would stop. Or Bitcoin would fork to China and non-China chains.

Bitcoin is much more centralized than is generally supposed. The top three
mining pools in China control Bitcoin, and they have a small number of large
mining installations each. It's much more concentrated than AWS.

~~~
Taek
The Chinese miners keep their nodes outside of China, actually. And I believe
many of them have non-internet relays (think point to point wifi, satellite,
etc.) for communicating with their nodes if China shuts down the internet.

Further, even without these protections there is enough hashrate outside of
China that the blockchain would not grind to a halt, you'd still get blocks
every 30 minutes or so.

China shutting down miners has been a topic of heavy discussion for a while,
and most I think are not concerned.

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Animats
No, they're not outside of China. Locating a Bitcoin farm in China allows
paying for power, equipment, and staff in yuan, while generating revenue in
dollars or euros, legally.

Northeast China mine: [1] Another China mine: [2] Mine in Kangding: [3] BW
Pool and Antpool, in Inner Mongolia: [4] OxBTC farm (possibly in Ordos): [5]

[1]
[https://www.youtube.com/watch?v=K8kua5B5K3I](https://www.youtube.com/watch?v=K8kua5B5K3I)
[2]
[https://www.youtube.com/watch?v=k3-7X80DXzY](https://www.youtube.com/watch?v=k3-7X80DXzY)
[3] [http://www.afr.com/technology/lisa-kangding-
story-20160706-g...](http://www.afr.com/technology/lisa-kangding-
story-20160706-gpzx7e) [4]
[https://bitcointalk.org/index.php?topic=969823.0](https://bitcointalk.org/index.php?topic=969823.0)
[5]
[https://www.facebook.com/oxbitcoin/videos/921660704629104/](https://www.facebook.com/oxbitcoin/videos/921660704629104/)

~~~
Taek
The mining is in China but the nodes are outside of China. Then they have
multiple means of talking to the nodes from the mining farms.

~~~
andirk
I think I get it. So 1) the computing power happens on hardware in China, but
then 2) the message can, if need be, relay the message of, say, a new mined
block to non-internet points that are able to escape The Great Firewall, then
3) outside of China it connects those messages to the internet. Is that right?

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xiphias
Bitcoin is taking away the biggest power that the governments have: printing
money from thin air. They need it especially for paying their military. There
may be a time in the future when it may worth for a government to protect
Bitcoin for their people, but that time is not now.

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danbruc
How many Internet exchange points do I have to take out to bring the entire
Internet down for all practical purposes, including the Bitcoin network?

