This is a quote from the book "B-Money" by Wei Dai
...andomly selected subset of the servers.

Since the servers must be trusted to a degree, some mechanism is needed tokeep them honest. Each server is required to deposit a certain amou
nt ofmoney in a special account to be used as potential fines or rewards forproof of misconduct. Also, each server must periodically publish andcommit to its current money creation and money own ership databases. Eachparticipant should verify that his own account balances are correct andthat the sum of the account balances is not greater than the total amountof money created. This preve...
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