NAT
Sharing one public address between many devices, which is how commercial VPN servers put hundreds of users behind a single IP.
Glossary
Port forwarding
What is Port forwarding?
Port forwarding is allowing inbound connections to reach your device through the VPN, rather than only outbound connections. It decides whether other peers can start a connection to you, or only the other way round. Without it a client is limited to peers that accept inbound connections, which narrows peer selection and makes seeding much harder.
Why it matters
It decides whether other peers can start a connection to you, or only the other way round. Without it a client is limited to peers that accept inbound connections, which narrows peer selection and makes seeding much harder.
What most explanations leave out
Transfers do not fail without it, which is the usual overstatement. BitTorrent clients behind NAT still reach every reachable peer, find them through DHT and peer exchange, and hole-punch with µTP; what you lose is inbound connectability and therefore ratio. It has been abused for hosting, so several major providers withdrew it. An open forwarded port is also an exposed service â it should point at a client that expects it and nothing else.
Related terms
Kill switch
A control that blocks all internet traffic if the VPN tunnel drops, rather than letting it fall back to your normal connection.
Referenced from
Questions
- What is Port forwarding?
- Allowing inbound connections to reach your device through the VPN, rather than only outbound connections.
- Why does Port forwarding matter when choosing a VPN?
- It decides whether other peers can start a connection to you, or only the other way round. Without it a client is limited to peers that accept inbound connections, which narrows peer selection and makes seeding much harder.
- What do most explanations of Port forwarding leave out?
- Transfers do not fail without it, which is the usual overstatement. BitTorrent clients behind NAT still reach every reachable peer, find them through DHT and peer exchange, and hole-punch with µTP; what you lose is inbound connectability and therefore ratio. It has been abused for hosting, so several major providers withdrew it. An open forwarded port is also an exposed service â it should point at a client that expects it and nothing else.
Terms are defined here because they appear in our scoring rubric or in provider reviews, not to fill a glossary.