Can Bitcoin's algorithm of 50% majority be adjusted to 95% agreement acceptance?

gene

sr. member

Activity: 252

Merit: 250

Quote from: cloud9 on June 05, 2011, 09:07:33 AM

Would the Bitcoin blockchain not be more secure if the blockchain acceptance criteria of 50% majority of nodes becomes 95% agreement of nodes at certain stages of high single mining pool node concentration?

See also http://forum.bitcoin.org/index.php?topic=12153.msg170894#msg170894 ?

Read up on the byzantine generals' problem.

Stefan Thomas

full member

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AKA: Justmoon

There is no "50% majority algorithm".

Bitcoin considers the longest block chain valid. So requiring anything other than simple majority would mean something like waiting for competing chain forks to reach a significantly different length before accepting either one. This is problematic because a single side chain block can make the main chain untrusted for 20 blocks (using the 95% case as an example).

Another way to put it: Requiring 95% acceptance essentially means that Bitcoin can be shut down with only 5% hashing power (because the rest of the network will no longer be able to achieve a 95% consensus).

cloud9

member

Activity: 126

Merit: 10

Would the Bitcoin blockchain not be more secure if the blockchain acceptance criteria of 50% majority of nodes becomes 95% agreement of nodes at certain stages of high single mining pool node concentration?

See also http://forum.bitcoin.org/index.php?topic=12153.msg170894#msg170894 ?

Topic: Can Bitcoin's algorithm of 50% majority be adjusted to 95% agreement acceptance? (Read 1151 times)