Книга: Distributed operating systems
2.5. GROUP COMMUNICATION
An underlying assumption intrinsic to RPC is that communication involves only two parties, the client and the server. Sometimes there are circumstances in which communication involves multiple processes, not just two. For example, consider a group of file servers cooperating to offer a single, fault-tolerant file service. In such a system, it might be desirable for a client to send a message to all the servers, to make sure that the request could be carried out even if one of them crashed. RPC cannot handle communication from one sender to many receivers, other than by performing separate RPCs with each one. In this section we will discuss alternative communication mechanisms in which a message can be sent to multiple receivers in one operation.