US Patent 8984292 Keyed human interactive proof players

A human interactive puzzle (HIP) authorization architecture where keyed and animated puzzles are executed by HIP players which are distinct and obfuscated to the point where breaking a single player is a relatively costly operation. A key is created in response to a request for a service, a HIP player is created based on the key, and a small installation executable is created that expands during installation to produce a computationally expensive data structure on the client relative to verification of the solution at the server. Thus, copying of the player or relay of the puzzle to a third system requires more time than allowed to receive the solution at the server.