4 ms·

Why does this affect torrent users?

5e92cb50239222b 3y ago
You need to be able to accept incoming connections to be able to fully participate in the network. Last time I seriously looked into this, BitTorrent clients didn't support any sort of NAT hole punching (and they often work over TCP in any case). Try running a client with and without a forwarded port and you will see massive difference in the number of peer connections.
- shrimp_emoji 3y ago
  So you're saying there's a chance
  - justsomehnguy 3y ago
    Of course, but if everyone is behind the NAT then no one in the swarm can connect to any one. If this is a popular torrent when someone with the connectivity would show up, eventually, but otherwise good luck. Recently it took me four months to complete one torrent and I was the one with the real IP.
- krossitalk 3y ago
  > NAT hole punching Could we just throw a STUN service in front of this, then?
- deleted 3y ago
  [deleted]
- Capricorn2481 3y ago
  I think I might be doing that already, as this is the first I've heard of this. Unless Mullvad was automatically opening a port for me. Is it possible a lot of average torrenters are already not port forwarding?
- 1letterunixname 3y ago
  Transmission has supported UPnP and NAT-PMP for many years. Although it doesn't always work as reliably as having a client with directly routable address(es), it does exist and works okay.
wincy 3y ago
Because a least one person has to have forwarded ports for them to form a direct connection. [0] This will degrade torrent performance and make torrenting worse, routers normally have uPnP enabled these days so we forget about it, but this will make it so you can’t connect to any other users who are also using Mullvad, for one. [0]https://superuser.com/questions/1053414/how-does-port-forwarding-help-in-torrents https://superuser.com/questions/1053414/how-does-port-forwar...
- bscphil 3y ago
  > routers normally have uPnP enabled these days From what I understand, uPnP took off for a while, but started to become much less common about a decade ago because of the security issues it caused. I think most routers come with it disabled by default now. (If you know of any surveys indicating otherwise, I'd be curious to read them.) Part of it is that hole punching became a standard feature for new protocols, so the need to forward ports has been reduced.
  - dharmab 3y ago
    Most consumer routers I've seen come with UPnP on while SOHO routers require explicit configuration
AraceliHarker 3y ago
In order to download a file via Torrent, someone has to upload it, and when using Torrent via VPN, the file cannot be uploaded without port forwarding.
- fruitreunion1 3y ago
  Actually, the initial seeder with a closed port can upload if someone else has an open port. Generally a lack of port forwarding means you can only connect to others who do have port forwarding.
- ddtaylor 3y ago
  Uploading can still happen even without open ports. The open port part is that someone has to initiate the connection after the connection is established anyone can send anything in any direction.

You need to be able to accept incoming connections to be able to fully participate in the network. Last time I seriously looked into this, BitTorrent clients didn't support any sort of NAT hole punching (and they often work over TCP in any case). Try running a client with and without a forwarded port and you will see massive difference in the number of peer connections.

shrimp_emoji 3y ago
So you're saying there's a chance
- justsomehnguy 3y ago
  Of course, but if everyone is behind the NAT then no one in the swarm can connect to any one. If this is a popular torrent when someone with the connectivity would show up, eventually, but otherwise good luck. Recently it took me four months to complete one torrent and I was the one with the real IP.
krossitalk 3y ago
> NAT hole punching Could we just throw a STUN service in front of this, then?
deleted 3y ago
[deleted]
Capricorn2481 3y ago
I think I might be doing that already, as this is the first I've heard of this. Unless Mullvad was automatically opening a port for me. Is it possible a lot of average torrenters are already not port forwarding?
1letterunixname 3y ago
Transmission has supported UPnP and NAT-PMP for many years. Although it doesn't always work as reliably as having a client with directly routable address(es), it does exist and works okay.

wincy 3y ago

Because a least one person has to have forwarded ports for them to form a direct connection. [0] This will degrade torrent performance and make torrenting worse, routers normally have uPnP enabled these days so we forget about it, but this will make it so you can’t connect to any other users who are also using Mullvad, for one. [0]https://superuser.com/questions/1053414/how-does-port-forwarding-help-in-torrents https://superuser.com/questions/1053414/how-does-port-forwar...

bscphil 3y ago
> routers normally have uPnP enabled these days From what I understand, uPnP took off for a while, but started to become much less common about a decade ago because of the security issues it caused. I think most routers come with it disabled by default now. (If you know of any surveys indicating otherwise, I'd be curious to read them.) Part of it is that hole punching became a standard feature for new protocols, so the need to forward ports has been reduced.
- dharmab 3y ago
  Most consumer routers I've seen come with UPnP on while SOHO routers require explicit configuration

AraceliHarker 3y ago

In order to download a file via Torrent, someone has to upload it, and when using Torrent via VPN, the file cannot be uploaded without port forwarding.

fruitreunion1 3y ago
Actually, the initial seeder with a closed port can upload if someone else has an open port. Generally a lack of port forwarding means you can only connect to others who do have port forwarding.
ddtaylor 3y ago
Uploading can still happen even without open ports. The open port part is that someone has to initiate the connection after the connection is established anyone can send anything in any direction.