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+# KnockKnock
+
+A Windows Service for providing services on-demand.
+
+## Overview
+
+KnockKnock acts as a TCP proxy, accepting connections and then forwarding all
+traffic between a client and upstream. It allows you to register commands to
+run when the service is idle (no open connections) and active (incoming
+connection(s)).
+
+For example, when forwarding connections to a Hyper-V VM, you could suspend the
+VM when there are no active connections, and resume it whenever a user attempts
+to connect.
+
+(Personally, this is how I use it--allowing my development VM to be suspended
+automatically when I am not connected to it through RDP.)
+
+## TODO / Limitations
+
+This is basically the minimum viable app that solves my own problem. I slapped
+it together in less than an hour.
+
+Configuration is hardcoded: it only forwards :1234 -> 10.200.0.10:3306; it
+always runs `SuspendVM` and `ResumeVM` against the `Debian` Hyper-V machine.
+The socket code is kind of janky and some activity patterns will make it
+explode.
+
+It works for me to proxy a Microsoft Remote Desktop Connection session through
+to a Hyper-V VM available on-demand.
+
+## License
+
+None. Do not redistribute.
+