BSP Developer's Guide

H
Implementing a MUX-Based Network Interface Driver
pDst
Expects NULL or a pointer to the mBlk structure into which to write the
extracted destination address (local) of the packet.
pESrc
Expects NULL or a pointer to the mBlk structure into which to write the
extracted source address (end, if different) of the packet.end source of packet.
pEDst
Expects NULL or a pointer to the mBlk structure into which to write the
extracted destination address (end, if different) of the packet.
H.6 Writing Protocols That Use the MUX API
This section describes how to port protocols to the MUX-based model. As shown
in Figure H-1, MUX-based protocols bind themselves to the MUX from above and
network interface drivers (ENDs) bind themselves to the MUX from below. Thus,
a protocol is layered on top of the MUX, which is layered on top of a network
interface driver. The responsibilities of each is given in Table H-3.
Table H-3
Layers and Responsibilities
Layer
Protocol
MUX
Network
Interface Driver
Responsibilities
Interface to the transport layer, and, through it, to application programs.
Copying packet data if needed.
Loading and unloading drivers.
Binding and unbinding protocols.
Calling each bound protocol’s receive routine.
Managing memory for buffer loaning.
Dealing with hardware.
Loading a driver into the system.
Unloading a driver from the system.
Loaning buffers to upper layers.
H
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