The PlayStation network is estimated to go down on Thursday for 3 hours due to some maintenance that will be taking place. It will take place the 12th February from 17:00 until 20:30 GMT. During the down time users will not be able to sign in to account management or the PlayStation store. PlayStation Home will also be unavailable.
During the down time for PS4 users,they will experience Online game play but only if their system is activated as the primary system and are signed in to their SEN account. They will also need to have their SEN authentication details cached. If you have not done this on you're PS4 system you will not be able to experience online game play.
For PS3 and PS Vita users you might experience limited PSN functionality, However you will be able to access the online community if you are signed in to you're SEN account and you're authentication details are cached.