[Twisted-Python] UDP vs TCP for bittorrent-style file transfer

Jean-Paul Calderone exarkun at divmod.com
Sun Sep 21 19:12:27 MDT 2008

On Sun, 21 Sep 2008 21:06:12 -0400, "Z. S. O." <tiredashell at gmail.com> wrote:
>> It's not easier to get UDP through NATs.  It's just as hard or harder.
>It must be a widely held error, then, because it's what I hear every time
>the subject arises. My understanding was that since UDP doesn't have the
>concept of "streams," most NATs will allow all UDP packets through to a
>given port one it is first hole-punched.
>Nat traversal aside, I'm also concerned about performance, and since TCP
>doesn't make in-order delivery optional, I'm still tempted to stick with

For a bittorrent-like application, you're also not particularly concerned
with *latency*, just throughput.  Allowing out-of-order delivery primarily
reduces latency, it doesn't do a whole lot for throughput.


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