simulating network errors/delays under windows [duplicate]

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Network tools that simulate sl开发者_JAVA技巧ow network connection

Are there any programs that can simulate an unstable network connection?

I am writing network applications and need to test its correctness under random network situations like delays/drops/disconnects/order errors/other. Currently I need only TCP stack, but good if I can test UDP stack too. Which programs can do this under windows? I think it should be something like network driver (like winpcap) or other network simulation device.

Thank you