This is the normal mechanism whereby stack size adjusts to demand. However, if the maximum stack size has been reached, we have a stack overflow and the program receives a Segmentation Fault.

This mechanism is used to resolve resource-name conflicts: if two library JAR files define a resource with the same global name, the local names will be used based on the stack-frame of the caller.

The lowest channel in this stack always does the same job: It maps the message being sent to whatever mechanism is used to transport that message.