Bugs and Under the Covers
While working with the camera, I had a few issues with the web interface. More than once, when trying to log in, I found that my password wasn't accepted. It was only after I cycled the power on the unit was I able to log in. This would be a big problem if I were trying to use the camera while away from home.
The other issue I saw was CPU usage. A couple of times while viewing the camera I noticed the fan on my laptop kick on, and the processor usage jump up into the high 90 percent levels for both of my CPUs. But when I stopped the camera applet, processor usage went back to normal.
I haven't seen this behavior on other Java pages, so it tells me that there must be some sort of programming error in the applet. I also got a "Too many users" error on one occasion when I brought up the camera's viewing page, but I was the only person viewing it. A quick "refresh" of the browser cleared the error, however.
Moving on to the internal exam, I did a quick port-scan of the box to see what operating system the camera was running. I found no interesting ports open, but the finger-print ID told me it was likely a Contiki OS, running on an Ethernut board. In the Figure 15, you can see that the wireless capabilities are provided by a mini-PCI card containing a RaLink 2560 chip.
Figure 15: HNC290G Main Board - Click for full-resolution image
I couldn't dig up any information on the large MARS chip, but the bulk of the functionality on the camera is provided by a Taifatech Tf-520 chip, which contains a web server, a JPEG encoder, networking support and other functions.