These network ports are used by Apple TV for communications on your network.
- TCP port 123 is used to communicate with a network time server.
- TCP port 3689 is used to communicate with iTunes while using the iTunes Library Sharing feature.
- UDP port 5353 is used by Apple TV for automatically finding computers with iTunes on your network using Bonjour.
- TCP port 80 is used for communicating with podcast servers.
- TCP port 80 and 443 are used for basic and secure communications with the iTunes Store via the Internet.
- TCP port 53 is used for regular DNS.
These are well-known ports used by Apple products, like iTunes. If you can use all the features of iTunes, these ports are likely already open on your firewall or NAT router. Note: These ports may also used by other services such as YouTube and Flickr.
If data does not sync or stream after entering a passcode on Apple TV (1st generation), see this article.
For information about troubleshooting Home Sharing on Apple TV (2nd generation), see this article.
For a complete list of network ports used by Apple products, see this article.