Re:Download responsibly
by Dylan16807 on Tuesday September 23, 2025 @02:29AM
(#45343482)
Torrents don't use anything like TCP congestion control and 100 connections will take a good chunk of bandwidth but much much less than 100 TCP flows.
... What? You realise BitTorrent runs over TCP/IP right?
Re:Download responsibly
by Dylan16807 on Tuesday September 23, 2025 @03:05PM
(#45351355)
TCP is a fallback if it can't use https://en.m.wikipedia.org/wiki/Micro_Transport_Protocol
I should have said they avoid TCP in favor of very different congestion control, sorry.
Interesting... It's been ~15 years since I last used BitTorrent personally, and I had asked a friend before replying and they swore that all their traffic was TCP -- though perhaps that may be due to CGNAT or something similar causing that fallback scenario you describe.
Thanks for the info, and sorry for jumping to a conclusion! Though my original point stands: Residential ISPs are generally not built to handle BitTorrent traffic flows (customer to customer or customer to other-ISP-customer across large geographic areas) so the bursty nature would cause congestion much easier, and BitTorrent itself isn't really made for these kinds of scenarios where content changes on a daily basis. CDNs exist for a reason, even if they're not readily available at reasonable prices for projects like OP!
For the second question, read the section on choking at https://deluge-torrent.org/userguide/bandwidthtweaking/ and Deluge appears to set the maximum number of connections per torrent of 120 with a global max of 250 (though I've seen 500+ in my brief searching, mostly for Transmission and other clients).
I'll admit a lot of my BitTorrent knowledge is dated (having last used it ~15 years ago) but the point remains: ISPs are built for "North-South" traffic, that is: To/From the customer and the networks with the content, not between customers, and certainly not between customers of differing ISPs.