Election Algorithms - A ring algorithm

Question

I been reading about Election algorithms in Distributed Systems. I read about the Bully Algorithm and understood it. I came across A Ring Algorithm, read about it an understood how it conducts the election but I could not understand how does it handle a situation when two processes 2 and 5 simultaneously discover that the coordinator 7is not functioning.

Each of these builds an ELECTION message and start circulating it.Eventually, both messages will go all the way around,and both 2 and 5 will convert them to COORDINATOR message, with exactly the same number and in the same order.

Who is going to be the coordinator (2or 5) and why according to this algorithm?

Answer 1

Say 2 and 5 discover that coordinator is not functioning, then both will initiate election algorithm.

Since the ring is unidirectional, the messages can only travel in one direction. The election message of 2 will reach 5 and election message of 5 will reach 2.

But interesting point is that whenever a node receives election message it appends its id to that message.Also when a node receives its own election message, it chooses the node with largest id to be new coordinator which will be 5 in both election message.

Hence 5 will become the coordinator and send the coordinator message.