Playstation network will be down for a scheduled maintenance on Monday 27th January for around 6 hours. Here's the official notice from Sony:
If youâ€™ve signed in to PlayStation Network any time since January 20th you will be able to play games online and access partner apps such as Netflix during this maintenance period. The PlayStation Store, PlayStation Home and Account Management will not be available during this time, and users may receive a maintenance notification when attempting to access these services.
We thank you for your patience and support and apologize for any inconvenience this may cause. In order to access online game play and partner apps during this routine maintenance, we ask that you please sign in to PlayStation Network prior to Monday, January 27th.
The scheduled downtime will take place in Europe, the maintenance will take place between 5.30pm and 11.30pm GMT, while North America will have the PSN taken down between 9.30am PT/12pm ET and 3.30pm PT/6.30pm ET