Bram Cohen (bramcohen) wrote,
Bram Cohen
bramcohen

upload/download ratios

Some BitTorrent web sites have implemented upload/download ratios, with banning of people whose ratio gets too out of whack. The problem with this approach (aside from that it's completely unclear that not uploading is a problem to begin with, since tit-for-tat works well) is that it's overly punishing. Just a little bit of threatening to ban people can get the overall balance to be very heavily weighted on the side of uploading, making it difficult for people to accomplish a reasonable amount of upload even if they try.

What typically happens in a single torrent is that at the beginning upload and download ratios are reasonably correlated, then over time people finish downloading, and some of them leave, but a significant number of seeds remain. After a while there's a period of time where there are many more seeders than downloaders. Anyone who joins the torrent at this late time will be generally get a download rate limited by their download capacity, and anyone who tries to upload to them will only be able to do so at a low rate. Such people will have very out of whack upload/download ratios, but they're downloading from otherwise unutilized upload resources, and hence not being anywhere near the drain on the system that their total upload/download ratio indicates.

A better approach would be to not count it against people when they download from heavily overseeded torrents. Or to just not use total upload/download ratios at all, or if you do only make them advisory and not a source of banning.
Subscribe

  • Moving

    I've moved my blog over to bramcohen.com. See you all there!

  • Practical Cryptography Corrected

    The book 'Practical Cryptography' is perfectly good for giving an overview of basic concepts in cryptography, but its immediate practical advice to…

  • Git Can't Be Made Consistent

    This post complains about Git lacking eventual consistency. I have a little secret for you: Git can't be made to have eventual consistency.…

  • Post a new comment

    Error

    Anonymous comments are disabled in this journal

    default userpic

    Your reply will be screened

    Your IP address will be recorded 

  • 26 comments

  • Moving

    I've moved my blog over to bramcohen.com. See you all there!

  • Practical Cryptography Corrected

    The book 'Practical Cryptography' is perfectly good for giving an overview of basic concepts in cryptography, but its immediate practical advice to…

  • Git Can't Be Made Consistent

    This post complains about Git lacking eventual consistency. I have a little secret for you: Git can't be made to have eventual consistency.…