A nonblocking group membership protocol for large-scale distributed systems

This paper presents a robust and nonblocking group membership protocol for large-scale distributed systems. This protocol uses the causal relation bet ween membership-updating messages (i.e., those specifying the adding and de leting of members) and allows the messages to be executed in a nonblocking manner. It differs from conventional group membership protocols in the foll owing points: (1) neither global locking nor global synchronization is requ ired; (2) membership-updating messages can be issued without being synchron ized with each other, and they can be executed immediately after their arri val. The proposed protocol therefore is highly scalable, and is more tolera nt to node and network failures and to network partitions than are the conv entional protocols. This paper proves that the proposed protocol works prop erly as long as messages can eventually be received by their destinations. This paper also discusses some design issues, such as multicast communicati on of the regular messages, fault tolerance and application to reliable com munication protocols (e.g., TCP/IP).