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Desktop Internet traffic measurement software
What good free software is there, that will run in the background and monitor how much is downloaded and uploaded?
If it would even report this data for several many computers (separate installs of course), so I could compare centrally - that would be neat. But less will do. :)
Please note, that just monitoring the network traffic is not enough, since that will include file transfers etc on the LAN.
Also note, that even though monitoring at your router/firewall would be a better solution, that is not always an option.