The Soekris net4501, Continued
Unfortunately, even though the board supports a single 3.3V PCI card, there is no opening on the rear of the case to allow a card to be accessed externally. A more minor downside is that the case is only available in an rather odd shade of green - even beige would have been better.
The case is opened by removing the four small retaining screws underneath - the top then slides away from the base.
Figure 3: Soekris net4501, top removed, view from the front
The CF card, which stores the system software, is retained in its slot by a screw-in post. While this shouldn't be necessary under normal use, it does prevent the card slipping out of the slot if the unit is treated more roughly while in transit.
The Type III miniPCI slot is the white slot visible between the CF card and the rear of the case. miniPCI is often found on laptop PC mainboards and in both the net45xx and laptops it is typically used for wireless network cards. Currently m0n0wall supports a number of 802.11b wireless cards as a network interface. Faster 802.11a and 802.11g specification cards are not currently supported by m0n0wall. This is a limitation of the standard device drivers built into FreeBSD 4.9 rather than m0n0wall itself.
However, the steel case itself makes an effective shield for the internal antennas on any installed wireless card, which will hinder wireless range and performance. There is also no specific opening or connection on the rear of the case for a cable to an external wireless antenna.
The best way round this would be to buy a pre-made wireless adapter cable with a chassis socket at one end. The case then only needs adapting by drilling an appropriately-sized hole to accept the chassis socket. This, and an external antenna, would easily improve the range of a net45xx /m0n0wall based Wireless Access Point.
Figure 4: Soekris net4501 mainboard
Figure 4 shows the highly integrated nature of the net4501 mainboard. The 3.3V PCI slot is on the top edge of the board. The three large semiconductors centre left and the three smaller semiconductors next to the RJ45 sockets on the far left are the Interface and MAC controllers for the three National Semiconductor DP83815 Fast Ethernet network interfaces. Centre right is the AMD 133 Mhz ElanSC520 CPU. The two chips above this are the SDRAM, 32MB each, and to the right of the CPU is the BIOS/BOOT Flash memory.