Which are correct, uTorrent or DUMeter speeds?

[torrentator]

Basically, I got uTorrent saying one thing and DU Meter saying another.

I've throttle upload speeds to 45kBps in uTorrent but DUMeter is showing upwards of 60kBps. If I shut down uTorrent, it'll go down to 0.0kBps for those who may have thought something else was uploading at the same time.

Download speeds are also different. DUMeter will show 40kBps +/- more than one uTorrent shows.

Who's right?

[Switeck]

You probably allowed too many connections for you line.

EACH connection adds to the bandwidth cost that isn't completely showed in µTorrent's speed gauges.

DHT also adds to the total bandwidth used.

[torrentator]

That's interesting. What's the point in specifying the max upload speed then?

[Firon]

DUMeter probably shows TCP/IP overhead as well. That would explain for the difference.

Or it can be broken like NetLimiter and show completely wrong speeds. Either one. Former's more likely, though.

[Switeck]

Upload Speed cannot be estimated very well just on a basis of number of connections you allow. The MTU setting for your line also has to be considered. The fundamental overheads for TCP/IP connections skyrocket as MTU gets smaller. µTorrent cannot even "see" any of this, as the networking layers are handled by the OS software and hardware drivers.

Your half open rate in µTorrent can jack up the numbers too, as attempting to make 10+ new connections (potentially every second) can eat bandwidth like nobody's business.