Network Driver info

Hi,
I want to know how a network driver works in QNX. I want to know about
the interaction between the Driver handler, Driver Interface and the Device
driver. What are their responsibilities ?? Do network drivers and handler
deal with the same set of 3 queues as other drivers do ???
Please suggest me any document or page where i can get hold of these
issues…
Thanking in advance…
Regards…
Sudip.