I cant sign in to PSN via PS3 since last night, still the case as of 9.00am this morning! Friend two doors down couldn't get on for a short while last night but was fine by 9ish last night.
We are on different ISP's as mine changed to PlusNet yesterday morning and he is on BT.
Because of my ISP change I spent hours last night and this morning trying to solve the problem thinking it was to do with my new connection or network. I tried everything, DMZ, resetting PS3 to default, resetting router to factory.......etc. No joy, I can surf the internet on PS3 all network settings fine, just can't log on to PSN!
I hope this is to do with maintenance (although it would have been nice if somebody at PSN let us know and I could have gone to bed before 2am!) and not a problem at my end as I'm totally stumped if it is.
EDIT: Solved yesterday. Double checked everything and modem settings had corrupted to LLCmux instead of VCmux. Changed this and all now working.