Throttle incoming connections?
Once upon a time, you could never have too much bandwidth :) However, with high speed file servers (eg Fileplanet), there are times when you want to download a 300 mb game demo at lunch time and not incur the wrath of your company's sysadmin for using up all the available bandwidth (even if it's just for 20 minutes or so).
Take a look at packet shaping, do a google on something like packet shaping+linux, or altq+packet shaping. If you just want to concepts, it should give you a decent practial background on the subject, even if you're using windows.
As fw noted altq does this very well. Also OpenBSD has altq integrated into its packetfilter
Download managers also do this job. You didn't specificy your platform, but I use getright on windows and you can throttle the bandwidth. It is adware too, so you needn't pay if you don't mind the stupid ads.
Gavin van Lelyveld
Your company should have a PacketShaper. (Disclosure: we do sell them). There are other, competing, products--Allot and Sitara come to mind. We like Packeteer's PacketShaper the best, though--the feature set is better.
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