I know this topic has been done to death, but i still can't connect to the playstation network!

My router is a Billion BiPac 7560 and so far i have given the Ps3 an ip address
(192.168.1.110), enabled DMZ for that address, opened all the ports given in the various guides on this site, and set up the connection manually using these values and specifying the correct DNS servers, and still i get the message: The connection with playstation network timed out.

Might this be a problem at sony's end or have i done something wrong?

Thanks