1.3.2.1 Addressing Mechanism
An internal addressing mechanism for delivering messages to objects is layered over the transport.
This mechanism is encompassed by:
Contexts, which are logical container spaces where objects exist "together" in memory and can efficiently communicate with each other.
A handle, which specifies the recipients of the message because all messages are addressed to some endpoint with a specific handle.
Both class and instance handles are valid. A message to a class handle is called a "static message". A message to an instance handle is called an "instance message".