PacketProtector is a Linux distribution for wireless routers, built on top of OpenWrt. The goal of this project is to transform the router into a unified threat management device.
The botnet was originally thought to be a test, an experiment to see how this technology worked. It was shut down quickly by the botnet operator once its existence became public knowledge.It now appears to have returned, and evolved into a new beast, PSYB
Internally, the DG834G contains a 150 MHz MIPS 4KEc CPU running Embedded Linux, the source code for which is available here.
Note that the D-Link G604T uses the same CPU and OS, so it most likely has very similar features and performance.