This appendix covers some advanced aspects of
Transparent Distributed Processing (TDP) or Qnet.
Low-level discussion of Qnet principles
The Qnet protocol extends interprocess communication (IPC) transparently over a network of microkernels. This is done by
taking advantage of the Neutrino's message-passing paradigm. Message passing is the central theme of Neutrino that manages
a group of cooperating processes by routing messages. This enhances the efficiency of all transactions among all processes
throughout the system.
Details of Qnet data communication
As mentioned before, Qnet relies on the message passing paradigm of Neutrino. Before any message pass, however, the application
(e.g. the client) must establish a connection to the server using the low-level ConnectAttach() function call:
Node descriptors
The <sys/netmgr.h> header defines the ND_LOCAL_NODE macro as zero. You can use it any time that you're dealing with node descriptors to make it obvious that you're talking about
the local node.