Yes I know which ports are required but unless you know what you are doing it might be confusing.
Make sure your router/computer allows access over the following ports
Port | Type | Protocol | Used By |
53 | TCP/UDP | DNS | DNS |
80 | TCP | HTTP | AirPlay, iTunes Store |
123 | TCP/UDP | NTP | Network Time |
443 | TCP | HTTPS | AirPlay, PhotoStream, iTunes Store |
554 | TCP/UDP | RTSP | AirPlay |
1900 | UDP | SSDP | Bonjour |
3689 | TCP | DAAP | iTunes, AirPlay, HomeSharing |
5297 | TCP | - | Bonjour |
5298 | TCP/UDP | - | Bonjour |
5350 | UDP | NAT | Bonjour |
5351 | UDP | NAT | Bonjour |
5353 | TCP/UDP | MDNS | Bonjour, AirPlay, HomeSharing |
8000-8999 | TCP | - | iTunes Radio Streams |
42000-42999 | TCP | - | iTunes Radio Streams |
49159 | UDP | MDNS (Win) | Bonjour, AirPlay |
49163 | UDP | MDNS (Win) | Bonjour, AirPlay |
Refer to your router manual/manufacturer for any settings that are specific to that model.
But if your router was provided by your ISP, you might be better asking them for help.