This is a quote from the book "B-Money" by Wei Dai
...casted on this channel remain thesame as in the first protocol, but the affected participants of eachtransaction should verify that the message has been received andsuccessfully processed by a r 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...
read full book block explorer