you may try troubleshoot by connect directly without router to identify whether your router setting or your ps3 has problem.

if direct connection to the modem no problem, then your ps3 is fine, but remember to adjust manually of your ps3 system clocks if your ps3 is the "big fat" model.

that would means your router settings need to be adjust. (read the manual of your ps3 or your router to adjust the correct settings)

try not to share your internet connection with torrent downloader, it will caused your ps3 lost connection.