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Distributed Database Systems
n to the coordinator in the decision phase. In the voting phase, the coordinator passes the vot-
ing instruction to site 2, site 2 votes and passes it to site 3, site 3 combines its vote and passes it
to site 4 and so on. When the nth participant adds its vote, the global decision is obtained and it
is passed backward to the participants, and eventually back to the coordinator. The linear 2PC
reduces the number of messages compared to centralized 2PC, but does not provide any paral-
lelism, thus, suffers from low response time performance. It is suitable for networks that do not
have broadcasting capability [Bernstein ...