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If there is still no response from its neighbor, and no update on the timestamp, the member will initiate a suspicion on its neighbor. Basically, the member will then send SuspectMemberMessage which includes a list of SuspectRequests to a list of recipients. Depending on the size of the view, the list of recipients may contain all the members in the view, if the view size is less than or equal to 4. If the view size is larger than 4, the list of recipients may have up to 7 members, which include 5 members preferred to be coordinator, the sender itself and a random member.  There is only one coordinator. How How the recipient reacts to the SuspectMemberMessage depends on whether it is the coordinator or not.  If it is the coordinator, it will start final check on the suspect member. To do final check, the coordinator sends HeartbeatRequestMessage to the suspect member, expecting a response from suspect member. At the same time, the coordinator also starts TCP final check, which initiates a TCP connection to the suspect member and exchanges the messages if the suspect member is still alive. 

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