Glossary A–ZLetter P
Port forwarding
Port forwarding is a rule in the router or firewall that passes incoming connections from the internet on a specific port to a device on the internal network.
A port is a number through which a service on a device is addressed, such as 443 for HTTPS.
Port forwarding is set up when a device or server needs to be reachable from outside, for example self-hosted management software for players at other sites. The players themselves usually do not need it, because they establish their own outbound connections. Occasionally a rule is added so that a player’s web interface can be reached remotely.
Every port forward makes a device addressable from the entire internet and therefore open to attack; automated scans find open ports quickly. Players’ web interfaces and remote maintenance access do not belong openly on the internet but behind a VPN. Anyone exposing a server of their own needs encryption, up-to-date software and strong authentication. Some routers set up forwarding automatically when devices request it (UPnP); this should be disabled in network segments containing screens.