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Just recently, my old access point (D-Link DWL900 AP) decided to stop communicating with the 2.4GHz world (although ap-utils still talks to it via wired ethernet). So for the moment, we’re using a wireless router, HP’s hn200w.

As an AP, it isn’t too bad, but as a router, it’s overkill for what I need — or is it? For my wireless network, an old P166 box running Gentoo Hardened acts as a DHCP server and OpenVPN endpoint, allowing my wireless clients to access the main network (at layer 2) through an AES256-encrypted tunnel.

The question is … can I get the wireless router to do this? The old PC is doing a good job, but it’s noisy, and a bit hungrier on the power than your typical wireless router. Then again, it has more storage capacity — but there’s nothing stopping me mounting more via NFS from the webserver — so this isn’t a big issue.

A look around revealed there was practically nothing known about this router. I knew from my nmap-probes, and this post that Linksys made the wireless interface — it in-fact uses a 16-bit PCMCIA Linksys WPC11. But what CPU did this thing run? What OS? The firmware had a few more references to “Linksys” in it, but didn’t reveal much else. It doesn’t run Linux — but rather some proprietary RTOS.

If you crack the box open, you’re greeted by a rather uninviting metal box. The PCB is covered by a metal earth shield that’s soldered to the motherboard — at the top, only two ~4mm antenna connectors poke out — these are the connectors on the wireless card.

Remove the cover however, and you’re greeted by a far more interesting mainboard. The critical chips such as the CPU (seen under the wireless card) have heatsinks on them — since I wanted this thing to continue working, I decided it was better to leave the heatsinks alone. The following show the mainboard with, and without the wireless card.

I’m nonethewiser about the CPU and other components. I realise some of these shots will need to be re-done since not everything came out clearly. The ethernet device seems to be a Realtek RTL8019AS device — very common on NE2000-compatible ISA network controllers. So whatever it is, it seems it has a 16-bit bus. All of these devices are supported by Linux, but something tells me the unit may lack the RAM or flash to run/store Linux. But nonetheless, it was fun cracking the box open and having a peek. If there’s any interest, I may investigate taking better shots of some of the ICs — although the main chips will still keep their heatsinks, since I’m not sure they’re easily re-attached.