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Given that most Bitcoin mining is done behind the Great Firewall[1], what happens if a midlevel bureaucrat partitions the network? (inadvertently or not) Seems

Given that most Bitcoin mining is done behind the Great Firewall[1], what happens if a midlevel bureaucrat partitions the network? (inadvertently or not) Seems there'd be a greater partion behind the firewall, and a lesser partition outside the firewall. How does the protocol deal with that? Assuming it's partitioned for days, weeks, or months? [1] Chun Wang comment from http://comments.gmane.org/gmane.comp.bitcoin.devel/8001 http://comments.gmane.org/gmane.comp.bitcoin.devel/8001 "Ignorant. You seem do not understand the current situation. We suffered from orphans a lot when we started in 2013. It is now your turn. If Western miners do not find a China-based VPN into China, or if Western pools do not manage to improve their connectivity to China, or run a node in China, it would be them to have higher orphans, not us. Because we have 50%+."

drcode 11y ago
All it would take is a SINGLE bitcoin user in all of China to figure out a way to sneak 50mb of data a day through the wall to prevent such a network partition.
- tlrobinson 11y ago
  Indeed, information wants to be free. There is already talk of launching satellites to disseminate block headers (though initially that's more to protect against Sybil attacks than to connect miners) https://groups.google.com/forum/#!forum/bitsat-project https://groups.google.com/forum/#!forum/bitsat-project
jackgavigan 11y ago
This is one of the reasons why the Bitcoin Blockchain is not necessarily the best choice as a platform for non-Bitcoin purposes. That's why most of the interest from banks is in blockchain technology - i.e. they're looking at creating their own blockchains.
patio11 11y ago
Assuming a complete net split? Then you have chain B in China and B' outside it, each a valid ledger of a different set of transactions. When they're reunited all the transactions only on B' get briefly invalidated as B' nodes reorganize to support the valid chain. (B is more valid than B' because it is presumably longer.). This will likely expose the network to double-spend attacks, where e.g. you take an output spent 2 weeks ago on B' and get a transaction to a B node which moves it internally in your wallet (or to a confederate). This will cause Bitcoin to forget the B' transaction and every subsequent transaction tainted by it. Your goal as the attacker is to have 1+ of these transactions give you economic value prior to your counterparty recognizing the reversal. Good news, though: a net split forking China off Bitcoin would probably result in Bitcoin's central authorities strongly recommending everyone stop processing transactions until they came back.

drcode 11y ago

All it would take is a SINGLE bitcoin user in all of China to figure out a way to sneak 50mb of data a day through the wall to prevent such a network partition.

tlrobinson 11y ago
Indeed, information wants to be free. There is already talk of launching satellites to disseminate block headers (though initially that's more to protect against Sybil attacks than to connect miners) https://groups.google.com/forum/#!forum/bitsat-project https://groups.google.com/forum/#!forum/bitsat-project

jackgavigan 11y ago

This is one of the reasons why the Bitcoin Blockchain is not necessarily the best choice as a platform for non-Bitcoin purposes. That's why most of the interest from banks is in blockchain technology - i.e. they're looking at creating their own blockchains.

patio11 11y ago

Assuming a complete net split? Then you have chain B in China and B' outside it, each a valid ledger of a different set of transactions. When they're reunited all the transactions only on B' get briefly invalidated as B' nodes reorganize to support the valid chain. (B is more valid than B' because it is presumably longer.). This will likely expose the network to double-spend attacks, where e.g. you take an output spent 2 weeks ago on B' and get a transaction to a B node which moves it internally in your wallet (or to a confederate). This will cause Bitcoin to forget the B' transaction and every subsequent transaction tainted by it. Your goal as the attacker is to have 1+ of these transactions give you economic value prior to your counterparty recognizing the reversal. Good news, though: a net split forking China off Bitcoin would probably result in Bitcoin's central authorities strongly recommending everyone stop processing transactions until they came back.