The IRIX networking design is based on the socket interface: mbufs are used to exchange messages within the kernel, and device drivers support the TCP/IP internet protocol suite by supporting the ifnet interface.
Since the kernel BSD-based networking framework and TCP/IP internet protocol suite implementation have changed little from previous releases of IRIX, porting your ifnet device driver to IRIX 5.3 from earlier releases of IRIX should be simple and straightforward.
Figure 9-1 displays the basic IRIX kernel networking architecture.
Figure 9-1 : IRIX 5.3 Kernel Network Architecture The left side of the figure shows the native socket-based TCP/IP protocol code, socket layer, and ifnet-based device drivers. This portion comes bundled in the basic IRIX system. Socket-based applications such as rlogin, rcp, NFS client and server, and the socket-based RPC library operate directly over this native networking framework.
The middle of the figure shows the optionally installed svr4net package, which provides compatibility support for user-level applications written to the STREAMS Transport Layer Interface (TLI). tpisocket is a kernel library module used by protocol-specific STREAMS pseudo-drivers, such as tpitcp, tpiudp, and so on, providing a TPI interface above the native kernel sockets-based network protocol stack.
The right side of the figure shows the optionally installed dlpi package which provides a STREAMS pseudo-driver that supports the Data Link Provider Interface (DLPI) for STREAMS-based kernel protocol stacks.
Refer to the IRIX Network Programming Guide and the SVR4 man pages for STREAMS, TLI, and DLPI programming information.