In order to access your PlayStation 3 via the Internet, your PSP must have firmware 3.50 or higher installed and your PS3 must have firmware 1.81 or higher installed. Before you are able to connect, your PS3 must be set on Remote Play mode and your PSP must be registered with your PS3.
To connect, simply go to [Remote Play] under [Network] on the PSP, select “Connect via Internet” and connect to a Wi-Fi hotspot with Internet access. You must sign into the PlayStation 3 using your PSN email address and password. If you have signed in correctly, you should see the PS3 XMB on your PSP screen.
For a detailed step-by-step guide on setting up Remote Play, see the Remote Play Guide.