+A good way to understand more about networking is two setup two computers: a server and a client. And the play around with the tools. The following tools and documentation are extremely useful.
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+Netcat
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+Simple tool to open or connect to TCP or UDP ports and output data through these channels. Build and test proxies. Powerful for debugging. _Cryptcat_ is a similar tool, but with support for cryptography
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+Sendip
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+Create and send IP, TCP or UDP packages. You are able to edit any value within these packages.
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