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It can also log all tunnelled packets for easier debugging of networking applications.
Screenshot on Windows

Configuration sample

To set up a pipe on the local computer that listens on port 12345 and relays the UDP packets to port 23456 with 10% packet loss and a random latency between 50–200ms, the configuration looks like this:
Pipes = { MyRelay = { listen = ":12345", remote = "localhost:23456", drop = 0.1, minLag = 50, maxLag = 200 } }
More about the configuration can be found in the included file config.sample.lua.

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