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Distributed Database Systems
Two distributed recovery protocols are 2PC pro-
tocol and 3PC protocol. 2PC is a blocking pr
oto-
col whereas 3PC is a non-blocking protocol.
The termination protocols that are used to han-
dle network partition can be classifi ed into two
categories: pessimistic protocols and optimistic
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protocols. In the case of non-replicated data-
bases, the termination protocols that are used
to deal with network partition are pessimistic.
In the case of replicated databases, both types of
termination protocols can be used.
EXERCISES
Multiple Choice Questions
(i) Which of the following is the probability
that the system is up ...