The RPC Manager protocol is a generic term that can be better defined as the cross-workstation protocol used by two SocketNodes to provide the reliable RPC transport. By this definition, the protocol is private to SocketNode and is completely encapsulated within SocketNode.
TCP/IP provides for reliable delivery of packets of information, where, for the purposes of this document, a packet is defined as an atomically written block of bytes.
Each packet has the same format, information within the packet header being used to decode the message that it carries. Messages fall into two categories, control messages and RPC messages.