Other Uses of the RPC Protocol

The intended use of this protocol is for calling remote procedures. That is, each call message is matched with a response message. However, the protocol itself is a message-passing protocol with which other (non-RPC) protocols can be implemented. Some of the non-RPC protocols supported by the RPC package are batching and broadcasting.

Batching

Batching allows a client to send an arbitrarily large sequence of call messages to a server; batching typically uses reliable byte stream protocols (like TCP) for its transport. In batching, the client never waits for a reply from the server, and the server does not send replies to batch requests. A sequence of batch calls is usually finished by a non-batch RPC call to flush the pipeline (with positive acknowledgment). For more information, see "Batching".

Broadcast RPC

In broadcast RPC, the client sends a broadcast packet to the network and waits for numerous replies. Broadcast RPC uses connectionless, packet-based protocols (like UDP) as its transports. Servers that support broadcast protocols only respond when the request is successfully processed, and are silent in the face of errors. Broadcast RPC uses the rpcbind service to achieve its semantics. See "Broadcast RPC" and "rpcbind Protocol" for further information.