Middleware Protocols. RPC, Message oriented Communication, etc. 2-5. An adapted reference model for networked communication. Remote Procedure Call Conventional Procedure Call i.e . read(fd,buf,bytes). a) Parameter passing in a local procedure call: the stack before the call to read
RPC, Message oriented
RPCs, i.e., enhance access transparency but they are not always appropriate to distributed system.
Persistence and Synchronicity
Different types of communications
The need for persistent communication services is clear in developing middleware for large-scale distributed applications.
Only transient or persistent communications, like only synchronous or asynchronous communications, are not sufficient!
Message passing communication
With new high performance multicomputer systems standard
socket primitives are insufficient.
Primitives have to be at a good level of abstraction and suitable for new
high speed interconnection protocols
MPI uses the underlying network and it assumes communication take place within a known group of processes
MPI supports all the previous transient communication diagrams except for (d)
Message oriented persistent communicationsMessage-Queuing Model basic idea: applications communicate by inserting messages in specific queues
The collection of queues is distributed across multiple machines queue names db
Resource reSerVation Protocol